Half-maximal downmodulation of cell surface CD4 required very little active Nef-ER and occurred as early as 4 h after addition of 4-HT .

Half-maximal downmodulation of <protein>cell surface CD4</protein> required very little active <protein>Nef-ER</protein> and occurred as early as 4 h after addition of 4-HT .


In contrast , 50 % downmodulation of HLA-A2 by Nef required 16 to 24 h and about 50- to 100-fold-greater concentrations of 4-HT .

In contrast , 50 % downmodulation of <protein>HLA-A2</protein> by <protein>Nef</protein> required 16 to 24 h and about 50- to 100-fold-greater concentrations of 4-HT .


These data suggest that HLA-A2 downmodulation may require certain threshold levels of active Nef .

These data suggest that <protein>HLA-A2</protein> downmodulation may require certain threshold levels of active <protein>Nef</protein> .


The differential timing of CD4 and HLA-A2 downmodulation may have implications for HIV pathogenesis and immune evasion .

The differential timing of <protein>CD4</protein> and <protein>HLA-A2</protein> downmodulation may have implications for HIV pathogenesis and immune evasion .


Regulation of chemokine mRNA expression in a rat model of vanadium-induced pulmonary inflammation .


Environmental and occupational exposure to vanadium dusts results in toxic effects mainly confined to the respiratory system .


Using a rat model of acute lung inflammation induced by intratracheal instillation of sodium metavanadate ( NaVO3 ) at the dose of 200 microg V/kg , we investigated the relationship between the cytologic characterization of pulmonary inflammation and the expression of chemokine mRNA .

Using a rat model of acute lung inflammation induced by intratracheal instillation of sodium metavanadate ( NaVO3 ) at the dose of 200 microg V/kg , we investigated the relationship between the cytologic characterization of pulmonary inflammation and the expression of <rna>chemokine mRNA</rna> .


Significant polymorphonuclear leukocyte ( PMN ) influx ( P < 0.01 ) into the lung was noted 4 h after NaVO3 instillation , whereas alveolar macrophages ( AMs ) in bronchoalveolar lavage ( BAL ) cells appeared to decrease significantly .

Significant <cell_type>polymorphonuclear leukocyte</cell_type> ( <cell_type>PMN</cell_type> ) influx ( P < 0.01 ) into the lung was noted 4 h after NaVO3 instillation , whereas <cell_type>alveolar macrophages</cell_type> ( <cell_type>AMs</cell_type> ) in <cell_type>bronchoalveolar lavage ( BAL ) cells</cell_type> appeared to decrease significantly .


In contrast , neither PMNs nor AMs changed substantially 1 h after NaVO3 instillation .

In contrast , neither <cell_type>PMNs</cell_type> nor <cell_type>AMs</cell_type> changed substantially 1 h after NaVO3 instillation .


By Northern analysis , macrophage inflammatory protein ( MIP ) -2 mRNA in BAL cells increased markedly 1 h after NaVO3 instillation and reduced a little bit at 4 h , whereas MIP-1alpha mRNA in BAL cells was expressed relatively high 1 h after NaVO3 instillation , although a basal expression was detected in control group , and returned rapidly nearly to control level at 4 h .

By Northern analysis , <rna>macrophage inflammatory protein ( MIP ) -2 mRNA</rna> in <cell_type>BAL cells</cell_type> increased markedly 1 h after NaVO3 instillation and reduced a little bit at 4 h , whereas <rna>MIP-1alpha mRNA</rna> in <cell_type>BAL cells</cell_type> was expressed relatively high 1 h after NaVO3 instillation , although a basal expression was detected in control group , and returned rapidly nearly to control level at 4 h .


Since MIP-2 is a potent PMN chemoattractant and MIP-1alpha is a potent macrophage/monocyte chemoattractant has been well known .

Since <protein>MIP-2</protein> is a potent <cell_type>PMN</cell_type> chemoattractant and <protein>MIP-1alpha</protein> is a potent macrophage/monocyte chemoattractant has been well known .


The facts that PMN influx was preceded by increased MIP-2 mRNA expression , suggesting that MIP-2 is involved in the development of NaVO3-induced pulmonary inflammation , whereas increased MIP-1alpha mRNA expression was followed by decreased AMs in BAL cells , suggesting AMs might be activated by MIP-1alpha , adherent to the lining surface of the airways and then resistant to be washed out .

The facts that <cell_type>PMN</cell_type> influx was preceded by increased MIP-2 mRNA expression , suggesting that <protein>MIP-2</protein> is involved in the development of NaVO3-induced pulmonary inflammation , whereas increased <rna>MIP-1alpha mRNA</rna> expression was followed by decreased <cell_type>AMs</cell_type> in <cell_type>BAL cells</cell_type> , suggesting <cell_type>AMs</cell_type> might be activated by <protein>MIP-1alpha</protein> , adherent to the lining surface of the airways and then resistant to be washed out .


To delineate the mechanisms of transcriptional activation , we recently cloned the 5'-flanking region of the MIP-2 gene .

To delineate the mechanisms of transcriptional activation , we recently cloned the <dna>5'-flanking region</dna> of the <dna>MIP-2 gene</dna> .


The promotor region contains consensus binding sites for transcription factor nuclear factor kappaB ( NF-kappaB ) and activator protein-1 ( AP-1 ) .

The <dna>promotor region</dna> contains <dna>consensus binding sites</dna> for <protein>transcription factor nuclear factor kappaB</protein> ( <protein>NF-kappaB</protein> ) and <protein>activator protein-1</protein> ( <protein>AP-1</protein> ) .


Using electrophoretic mobility shift assay , increased nuclear NF-kappaB , not AP-1 , binding activity was detected 1 h after NaVO3 instillation , which correlated with the induction of MIP-2 mRNA .

Using electrophoretic mobility shift assay , increased nuclear <protein>NF-kappaB</protein> , not <protein>AP-1</protein> , binding activity was detected 1 h after NaVO3 instillation , which correlated with the induction of <rna>MIP-2 mRNA</rna> .


p65 ( Rel A ) and p50 protein appears to be involved in MIP-2 NF-kappaB binding .

<protein>p65 ( Rel A )</protein> and <protein>p50 protein</protein> appears to be involved in MIP-2 <protein>NF-kappaB</protein> binding .


Taken together , our studies suggest that MIP-2 is an important mediator of NaVO3-induced pulmonary inflammation in the rat model .

Taken together , our studies suggest that <protein>MIP-2</protein> is an important mediator of NaVO3-induced pulmonary inflammation in the rat model .


In addition , elevated MIP-2 mRNA levels are accompanied by increased NF-kappaB binding activity in BAL cells , suggesting possible MIP-2 transcriptional regulation through NF-kappaB .

In addition , elevated <rna>MIP-2 mRNA</rna> levels are accompanied by increased <protein>NF-kappaB</protein> binding activity in <cell_type>BAL cells</cell_type> , suggesting possible <protein>MIP-2</protein> transcriptional regulation through <protein>NF-kappaB</protein> .


Activation of signal transduction and apoptosis in healthy lymphomonocytes exposed to bystander HIV-1-infected cells .

Activation of signal transduction and apoptosis in <cell_type>healthy lymphomonocytes</cell_type> exposed to bystander <cell_type>HIV-1-infected cells</cell_type> .


Persistent activation of the immune system is one of the hallmarks of HIV-1 infection .


In this study we analysed the induction of factors involved in cytokine signal transduction , such as STAT 1 proteins and IRF-1 mRNA , in normal peripheral blood mononuclear cells ( PBMC ) exposed to HIV-infected cells , and the induction of apoptosis .

In this study we analysed the induction of factors involved in cytokine signal transduction , such as <protein>STAT 1 proteins</protein> and <rna>IRF-1 mRNA</rna> , in <cell_type>normal peripheral blood mononuclear cells</cell_type> ( <cell_type>PBMC</cell_type> ) exposed to <cell_type>HIV-infected cells</cell_type> , and the induction of apoptosis .


Western blot analyses and reverse transcriptase-polymerase chain reaction results indicate that both cells infected with a X4 strain and cells infected with a R5 strain are able to increase intracellular levels of STAT 1alpha and beta proteins as well as IRF-1 mRNA .

Western blot analyses and reverse transcriptase-polymerase chain reaction results indicate that both cells infected with a X4 strain and cells infected with a R5 strain are able to increase intracellular levels of <protein>STAT 1alpha and beta</protein> proteins as well as <rna>IRF-1 mRNA</rna> .


This effect was prevented by neutralizing antibodies against interferon-alpha ( IFN-alpha ) .

This effect was prevented by neutralizing antibodies against <protein>interferon-alpha</protein> ( <protein>IFN-alpha</protein> ) .


HIV-1-infected cells dose-dependently induced apoptotic commitment in normal PBMC , as revealed by DNA fragmentation analysis , but this was not accompanied by an increase of caspase-3 activity , even if a slight up-regulation of IL-1beta-converting enzyme mRNA was detected .

<cell_type>HIV-1-infected cells</cell_type> dose-dependently induced apoptotic commitment in <cell_type>normal PBMC</cell_type> , as revealed by DNA fragmentation analysis , but this was not accompanied by an increase of caspase-3 activity , even if a slight up-regulation of <rna>IL-1beta-converting enzyme mRNA</rna> was detected .


Apoptosis induction could be abrogated mainly by antibodies against tumour necrosis factor-alpha ( TNF-alpha ) and , to a lesser extent , by antibodies against IFN-gamma .

Apoptosis induction could be abrogated mainly by <protein>antibodies</protein> against <protein>tumour necrosis factor-alpha</protein> ( <protein>TNF-alpha</protein> ) and , to a lesser extent , by <protein>antibodies</protein> against <protein>IFN-gamma</protein> .


All these findings suggest that uninfected PBMC can undergo activation of signal transduction and apoptosis after exposure to bystander HIV-infected cells , subsequent to the induction of cytokines such as IFNs and TNF-alpha .

All these findings suggest that <cell_type>uninfected PBMC</cell_type> can undergo activation of signal transduction and apoptosis after exposure to bystander <cell_type>HIV-infected cells</cell_type> , subsequent to the induction of <protein>cytokines</protein> such as <protein>IFNs</protein> and <protein>TNF-alpha</protein> .


The physical association of protein kinase C theta with a lipid raft-associated inhibitor of kappa B factor kinase ( IKK ) complex plays a role in the activation of the NF-kappa B cascade by TCR and CD28 .

The physical association of <protein>protein kinase C theta</protein> with a lipid raft-associated inhibitor of <protein>kappa B factor kinase ( IKK ) complex</protein> plays a role in the activation of the NF-kappa B cascade by <protein>TCR</protein> and <protein>CD28</protein> .


We investigated the role of protein kinase C theta ( PKCtheta ) in the activation of the NF-kappaB cascade in primary human CD4 ( + ) lymphocytes .

We investigated the role of <protein>protein kinase C theta</protein> ( <protein>PKCtheta</protein> ) in the activation of the <protein>NF-kappaB</protein> cascade in <cell_type>primary human CD4 ( + ) lymphocytes</cell_type> .


Among six or so PKC isoforms expressed in T cells , only PKCtheta participates in the assembly of the supramolecular activation clusters at the contact site of the TCR with Ag .

Among six or so <protein>PKC isoforms</protein> expressed in <cell_type>T cells</cell_type> , only <protein>PKCtheta</protein> participates in the assembly of the supramolecular activation clusters at the contact site of the <protein>TCR</protein> with <protein>Ag</protein> .


Signaling via both the TCR and CD28 is required for optimal activation of the multisubunit IkappaB kinase ( IKK ) complex in primary human T lymphocytes ; this activation could be inhibited by a Ca ( 2+ ) -independent PKC isoform inhibitor , rottlerin .

Signaling via both the <protein>TCR</protein> and <protein>CD28</protein> is required for optimal activation of the <protein>multisubunit IkappaB kinase ( IKK ) complex</protein> in <cell_type>primary human T lymphocytes</cell_type> ; this activation could be inhibited by a Ca ( 2+ ) -independent PKC isoform inhibitor , rottlerin .


Moreover , endogenous PKCtheta physically associates with activated IKK complexes in CD3/CD28-costimulated primary CD4 ( + ) T cells .

Moreover , endogenous <protein>PKCtheta</protein> physically associates with activated <protein>IKK complexes</protein> in <cell_type>CD3/CD28-costimulated primary CD4 ( + ) T cells</cell_type> .


The same set of stimuli also induced relocation of endogenous PKCtheta and IKKs to a GM1 ganglioside-enriched , detergent-insoluble membrane compartment in primary T cells .

The same set of stimuli also induced relocation of endogenous <protein>PKCtheta</protein> and <protein>IKKs</protein> to a GM1 ganglioside-enriched , detergent-insoluble membrane compartment in <cell_type>primary T cells</cell_type> .


IKKs recruited to these lipid rafts were capable of phosphorylating a recombinant IkappaBalpha sustrate .

<protein>IKKs</protein> recruited to these lipid rafts were capable of phosphorylating a recombinant IkappaBalpha sustrate .


Confocal microscopy further demonstrated that exogenously expressed PKCtheta and IKKss colocalize in the membrane of CD3/CD28-costimulated Jurkat T cells .

Confocal microscopy further demonstrated that exogenously expressed <protein>PKCtheta</protein> and <protein>IKKss</protein> colocalize in the membrane of <cell_line>CD3/CD28-costimulated Jurkat T cells</cell_line> .


Constitutively active but not kinase-inactive PKCtheta activated IKKbeta in Jurkat T cells .

Constitutively active but not <protein>kinase-inactive PKCtheta</protein> activated <protein>IKKbeta</protein> in <cell_line>Jurkat T cells</cell_line> .


Expression of dominant-active PKCtheta also had stimulatory effects on the CD28 response element of the IL-2 promoter .

Expression of <protein>dominant-active PKCtheta</protein> also had stimulatory effects on the <dna>CD28 response element</dna> of the <dna>IL-2 promoter</dna> .


Taken together , these data show that the activation of PKCtheta by the TCR and CD28 plays an important role in the assembly and activation of IKK complexes in the T cell membrane

Taken together , these data show that the activation of <protein>PKCtheta</protein> by the <protein>TCR</protein> and <protein>CD28</protein> plays an important role in the assembly and activation of <protein>IKK complexes</protein> in the T cell membrane


T-cell -mediated regulation of osteoclastogenesis by signalling cross-talk between RANKL and IFN-gamma .

<cell_type>T-cell</cell_type> -mediated regulation of osteoclastogenesis by signalling cross-talk between <protein>RANKL</protein> and <protein>IFN-gamma</protein> .


Bone resorption is regulated by the immune system , where T-cell expression of RANKL ( receptor activator of nuclear factor ( NF ) -kappaB ligand ) , a member of the tumour-necrosis factor family that is essential for osteoclastogenesis , may contribute to pathological conditions , such as autoimmune arthritis .

Bone resorption is regulated by the immune system , where <cell_type>T-cell</cell_type> expression of <protein>RANKL</protein> ( <protein>receptor activator of nuclear factor ( NF ) -kappaB ligand</protein> ) , a member of the <protein>tumour-necrosis factor family</protein> that is essential for osteoclastogenesis , may contribute to pathological conditions , such as autoimmune arthritis .


However , whether activated T cells maintain bone homeostasis by counterbalancing the action of RANKL remains unknown .

However , whether <cell_type>activated T cells</cell_type> maintain bone homeostasis by counterbalancing the action of <protein>RANKL</protein> remains unknown .


Here we show that T-cell production of interferon ( IFN ) -gamma strongly suppresses osteoclastogenesis by interfering with the RANKL -RANK signalling pathway .

Here we show that <cell_type>T-cell</cell_type> production of <protein>interferon ( IFN ) -gamma</protein> strongly suppresses osteoclastogenesis by interfering with the <protein>RANKL</protein> -RANK signalling pathway .


IFN-gamma induces rapid degradation of the RANK adapter protein , TRAF6 ( tumour necrosis factor receptor-associated factor 6 ) , which results in strong inhibition of the RANKL -induced activation of the transcription factor NF-kappaB and JNK .

<protein>IFN-gamma</protein> induces rapid degradation of the <protein>RANK adapter protein</protein> , <protein>TRAF6</protein> ( <protein>tumour necrosis factor receptor-associated factor 6</protein> ) , which results in strong inhibition of the <protein>RANKL</protein> -induced activation of the <protein>transcription factor</protein> <protein>NF-kappaB</protein> and <protein>JNK</protein> .


This inhibition of osteoclastogenesis is rescued by overexpressing TRAF6 in precursor cells , which indicates that TRAF6 is the target critical for the IFN-gamma action .

This inhibition of osteoclastogenesis is rescued by overexpressing <protein>TRAF6</protein> in <cell_type>precursor cells</cell_type> , which indicates that <protein>TRAF6</protein> is the target critical for the <protein>IFN-gamma</protein> action .


Furthermore , we provide evidence that the accelerated degradation of TRAF6 requires both its ubiquitination , which is initiated by RANKL , and IFN-gamma -induced activation of the ubiquitin-proteasome system .

Furthermore , we provide evidence that the accelerated degradation of <protein>TRAF6</protein> requires both its ubiquitination , which is initiated by <protein>RANKL</protein> , and <protein>IFN-gamma</protein> -induced activation of the ubiquitin-proteasome system .


Our study shows that there is cross-talk between the tumour necrosis factor and IFN families of cytokines , through which IFN-gamma provides a negative link between T-cell activation and bone resorption .

Our study shows that there is cross-talk between the <protein>tumour necrosis factor</protein> and <protein>IFN families</protein> of <protein>cytokines</protein> , through which <protein>IFN-gamma</protein> provides a negative link between <cell_type>T-cell</cell_type> activation and bone resorption .


Our results may offer a therapeutic approach to treat the inflammation-induced tissue breakdown .


Stromal-derived factor 1 and thrombopoietin regulate distinct aspects of human megakaryopoiesis .

<protein>Stromal-derived factor 1</protein> and <protein>thrombopoietin</protein> regulate distinct aspects of human megakaryopoiesis .


The role of the chemokine binding stromal-derived factor 1 ( SDF-1 ) in normal human megakaryopoiesis at the cellular and molecular levels and its comparison with that of thrombopoietin ( TPO ) have not been determined .

The role of the <protein>chemokine</protein> binding <protein>stromal-derived factor 1</protein> ( <protein>SDF-1</protein> ) in normal human megakaryopoiesis at the cellular and molecular levels and its comparison with that of <protein>thrombopoietin</protein> ( <protein>TPO</protein> ) have not been determined .


In this study it was found that SDF-1 , unlike TPO , does not stimulate alpha ( IIb ) beta ( 3 ) ( + ) cell proliferation or differentiation or have an antiapoptotic effect .

In this study it was found that <protein>SDF-1</protein> , unlike <protein>TPO</protein> , does not stimulate alpha ( IIb ) beta ( 3 ) ( + ) cell proliferation or differentiation or have an antiapoptotic effect .


However , it does induce chemotaxis , trans-Matrigel migration , and secretion of matrix metalloproteinase 9 ( MMP-9 ) and vascular endothelial growth factor ( VEGF ) by these cells , and both SDF-1 and TPO increase the adhesion of alpha ( IIb ) beta ( 3 ) ( + ) cells to fibrinogen and vitronectin .

However , it does induce chemotaxis , trans-Matrigel migration , and secretion of matrix <protein>metalloproteinase 9</protein> ( <protein>MMP-9</protein> ) and <protein>vascular endothelial growth factor</protein> ( <protein>VEGF</protein> ) by these cells , and both <protein>SDF-1</protein> and <protein>TPO</protein> increase the adhesion of <cell_type>alpha ( IIb ) beta ( 3 ) ( + ) cells</cell_type> to <protein>fibrinogen</protein> and <protein>vitronectin</protein> .


Investigating the intracellular signaling pathways induced by SDF-1 and TPO revealed some overlapping patterns of protein phosphorylation/activation ( mitogen-activated protein kinase [ MAPK ] p42/44 , MAPK p38 , and AKT [ protein kinase B ] ) and some that were distinct for TPO ( eg , JAK-STAT ) and for SDF-1 ( eg , NF-kappa B ) .

Investigating the intracellular signaling pathways induced by <protein>SDF-1</protein> and <protein>TPO</protein> revealed some overlapping patterns of protein phosphorylation/activation ( <protein>mitogen-activated protein kinase [ MAPK ] p42/44</protein> , <protein>MAPK p38</protein> , and <protein>AKT [ protein kinase B ]</protein> ) and some that were distinct for <protein>TPO</protein> ( eg , <protein>JAK-STAT</protein> ) and for <protein>SDF-1</protein> ( eg , <protein>NF-kappa B</protein> ) .


It was also found that though inhibition of phosphatidyl-inositol 3-kinase ( PI-3K ) by LY294002 in alpha ( IIb ) beta ( 3 ) ( + ) cells induced apoptosis and inhibited chemotaxis adhesion and the secretion of MMP-9 and VEGF , the inhibition of MAPK p42/44 ( by the MEK inhibitor U0126 ) had no effect on the survival , proliferation , and migration of these cells .

It was also found that though inhibition of <protein>phosphatidyl-inositol 3-kinase</protein> ( <protein>PI-3K</protein> ) by LY294002 in <cell_type>alpha ( IIb ) beta ( 3 ) ( + ) cells</cell_type> induced apoptosis and inhibited chemotaxis adhesion and the secretion of <protein>MMP-9</protein> and <protein>VEGF</protein> , the inhibition of <protein>MAPK p42/44</protein> ( by the MEK inhibitor U0126 ) had no effect on the survival , proliferation , and migration of these cells .


Hence , it is suggested that the proliferative effect of TPO is more related to activation of the JAK-STAT pathway ( unique to TPO ) , and the PI-3K-AKT axis is differentially involved in TPO- and SDF-1-dependent signaling .

Hence , it is suggested that the proliferative effect of <protein>TPO</protein> is more related to activation of the JAK-STAT pathway ( unique to <protein>TPO</protein> ) , and the PI-3K-AKT axis is differentially involved in TPO- and SDF-1-dependent signaling .


Accordingly , PI-3K is involved in TPO -mediated inhibition of apoptosis , TPO- and SDF-1-regulated adhesion to fibrinogen and vitronectin , and SDF-1 -mediated migration .

Accordingly , <protein>PI-3K</protein> is involved in <protein>TPO</protein> -mediated inhibition of apoptosis , TPO- and SDF-1-regulated adhesion to <protein>fibrinogen</protein> and <protein>vitronectin</protein> , and <protein>SDF-1</protein> -mediated migration .


This study expands the understanding of the role of SDF-1 and TPO in normal human megakaryopoiesis and indicates the molecular basis of the observed differences in cellular responses .

This study expands the understanding of the role of <protein>SDF-1</protein> and <protein>TPO</protein> in normal human megakaryopoiesis and indicates the molecular basis of the observed differences in cellular responses .


( Blood. 2000 ; 96 : 4142-4151 )


Adhesion of immature and mature T cells induces in human thymic epithelial cells ( TEC ) activation of IL-6 gene trascription factors ( NF-kappaB and NF-IL6 ) and IL-6 gene expression : role of alpha3beta1 and alpha6beta4 integrins .

Adhesion of <cell_type>immature and mature T cells</cell_type> induces in <cell_type>human thymic epithelial cells</cell_type> ( <cell_type>TEC</cell_type> ) activation of <protein>IL-6 gene trascription factors</protein> ( <protein>NF-kappaB</protein> and <protein>NF-IL6</protein> ) and IL-6 gene expression : role of <protein>alpha3beta1 and alpha6beta4 integrins</protein> .


T cell precursors homed to thymus develop in close contact with stromal cells .

<cell_type>T cell precursors</cell_type> homed to thymus develop in close contact with <cell_type>stromal cells</cell_type> .


Among them , thymic epithelial cells ( TEC ) are known to exert dominant roles in their survival and functional shaping .

Among them , <cell_type>thymic epithelial cells</cell_type> ( <cell_type>TEC</cell_type> ) are known to exert dominant roles in their survival and functional shaping .


Key molecules mediating TEC / thymocytes interactions include cytokines and growth factors secreted by the two cell types and adhesion receptors mediating cell contact .

Key molecules mediating <cell_type>TEC</cell_type> / <cell_type>thymocytes</cell_type> interactions include <protein>cytokines</protein> and <protein>growth factors</protein> secreted by the two cell types and <protein>adhesion receptors</protein> mediating cell contact .


Signaling events triggered in thymocytes by adhesion to epithelial cells have been extensively investigated , whereas little is known on the opposite phenomenon .

Signaling events triggered in <cell_type>thymocytes</cell_type> by adhesion to <cell_type>epithelial cells</cell_type> have been extensively investigated , whereas little is known on the opposite phenomenon .


We have previously investigated this issue in a co-culture system composed of TEC cultures derived from human normal thymus and heterologous thymocytes .

We have previously investigated this issue in a co-culture system composed of <cell_type>TEC cultures</cell_type> derived from human normal thymus and <cell_type>heterologous thymocytes</cell_type> .


We demonstrated that thymocytes adhere to TEC involving beta1 and beta4 integrins and induce the clustering of alpha3beta1 and alpha6beta4 heterodimers at the TEC surface .

We demonstrated that <cell_type>thymocytes</cell_type> adhere to <cell_type>TEC</cell_type> involving <protein>beta1 and beta4 integrins</protein> and induce the clustering of <protein>alpha3beta1 and alpha6beta4 heterodimers</protein> at the TEC surface .


In addition thymocyte adhesion was followed by activation of NF-kappaB and NF-IL6 gene transcription factors and enhanced IL-6 production .

In addition thymocyte adhesion was followed by activation of <protein>NF-kappaB</protein> and <protein>NF-IL6</protein> <protein>gene transcription factors</protein> and enhanced IL-6 production .


The two latter phenomena were reproduced by the cross-linking of the alpha3 , alpha6 , beta1 and beta4 integrins , thus implying that the alpha3beta1 and alpha6beta4 heterodimers can signal during thymocyte adhesion .

The two latter phenomena were reproduced by the cross-linking of the <protein>alpha3</protein> , <protein>alpha6</protein> , <protein>beta1 and beta4 integrins</protein> , thus implying that the <protein>alpha3beta1 and alpha6beta4 heterodimers</protein> can signal during thymocyte adhesion .


We have extended our previous work investigating in the same experimental setting the inducing activity of non stimulated or activated policlonal or clonal mature T cells as representative of the more mature thymocyte subset .

We have extended our previous work investigating in the same experimental setting the inducing activity of non stimulated or activated <cell_type>policlonal or clonal mature T cells</cell_type> as representative of the more <cell_type>mature thymocyte subset</cell_type> .


We found that adhesion of unstimulated T cell i ) involved beta1 , but not beta4 integrin functions at the surface ii ) induced the clustering of alpha3beta1 , but not alpha2beta1 heterodimers at the TEC surface and iii ) up-regulated the nuclear binding activity of NF-kappaB transcription factor and the IL-6 secretion .

We found that adhesion of <cell_type>unstimulated T cell</cell_type> i ) involved beta1 , but not beta4 integrin functions at the surface ii ) induced the clustering of <protein>alpha3beta1</protein> , but not <protein>alpha2beta1 heterodimers</protein> at the TEC surface and iii ) up-regulated the nuclear binding activity of <protein>NF-kappaB transcription factor</protein> and the IL-6 secretion .


We propose that alpha3beta1 and alpha6beta4 heterodimers are induced to cluster at the TEC surface recognizing yet unknown cellular ligands differentially expressed during T cell development .

We propose that <protein>alpha3beta1 and alpha6beta4 heterodimers</protein> are induced to cluster at the TEC surface recognizing yet unknown <protein>cellular ligands</protein> differentially expressed during T cell development .


Identification and characterization of SKAT-2 , a novel Th2-specific zinc finger gene .

Identification and characterization of <dna>SKAT-2</dna> , a novel <dna>Th2-specific zinc finger gene</dna> .


We have identified a novel Kruppel-type zinc finger ( ZF ) gene , SKAT-2 , which is selectively expressed by murine Th2 cells .

We have identified a novel <dna>Kruppel-type zinc finger ( ZF ) gene</dna> , <dna>SKAT-2</dna> , which is selectively expressed by <cell_type>murine Th2 cells</cell_type> .


The protein encoded by this gene has 14 C2H2-type ZF tandemly arrayed at its C terminus and N-terminal SCAN box and KRAB domains .

The protein encoded by this gene has 14 C2H2-type ZF tandemly arrayed at its <dna>C terminus</dna> and <dna>N-terminal</dna> <dna>SCAN box</dna> and <dna>KRAB domains</dna> .


SKAT-2 is tissue restricted in expression at the RNA level , detectable only in brain and at low levels in kidney and spleen and few hematopoietic cell lines .

<dna>SKAT-2</dna> is tissue restricted in expression at the RNA level , detectable only in brain and at low levels in kidney and spleen and few <cell_line>hematopoietic cell lines</cell_line> .


By in situ hybridization , SKAT-2 expression was found to peak in antigen-stimulated CD4 ( + ) T cells after 2-3 days of culture under Th2 but not Th1 biasing conditions .

By in situ hybridization , <dna>SKAT-2</dna> expression was found to peak in antigen-stimulated <cell_type>CD4 ( + ) T cells</cell_type> after 2-3 days of culture under Th2 but not Th1 biasing conditions .


This pattern of expression closely mirrored that of GATA-3 in the same cells .

This pattern of expression closely mirrored that of <protein>GATA-3</protein> in the same cells .


In transient transfection experiments in phorbol 12-myristate 13-acetate/ionomycin-stimulated EL4 cells , SKAT-2 was found to up-regulate the activity of the IL-4 but not the IL-5 promoter , contrasting with the ability of GATA-3 to activate both promoters .

In transient transfection experiments in phorbol 12-myristate 13-acetate/ionomycin-stimulated <cell_line>EL4 cells</cell_line> , <dna>SKAT-2</dna> was found to up-regulate the activity of the <dna>IL-4 but not the IL-5 promoter</dna> , contrasting with the ability of <protein>GATA-3</protein> to activate both <dna>promoters</dna> .


This result was confirmed using clones of EL4 cells stably expressing an inducible form of SKAT-2 , thus SKAT-2 is a novel Th2-specific gene that may play a role in selective regulation of cytokine genes in T cells .

This result was confirmed using clones of <cell_line>EL4 cells</cell_line> stably expressing an inducible form of <dna>SKAT-2</dna> , thus <dna>SKAT-2</dna> is a novel <dna>Th2-specific gene</dna> that may play a role in selective regulation of <dna>cytokine genes</dna> in <cell_type>T cells</cell_type> .


hsp70 interacting protein Hip does not affect glucocorticoid receptor folding by the hsp90-based chaperone machinery except to oppose the effect of BAG-1 .

<protein>hsp70 interacting protein Hip</protein> does not affect <protein>glucocorticoid receptor</protein> folding by the hsp90-based chaperone machinery except to oppose the effect of <protein>BAG-1</protein> .


Reticulocyte lysate contains a chaperone system that assembles glucocorticoid receptor ( GR ) .hsp90 heterocomplexes .

Reticulocyte lysate contains a chaperone system that assembles <protein>glucocorticoid receptor ( GR ) .hsp90 heterocomplexes</protein> .


Using purified proteins , we have prepared a five-protein heterocomplex assembly system consisting of two proteins essential for heterocomplex assembly- hsp90 and hsp70 -and three proteins that act as co-chaperones to enhance assembly- Hop , hsp40 , p23 [ Morishima , Y. , Kanelakis , K. C. , Silverstein , A. M. , Dittmar , K. D. , Estrada , L. , and Pratt , W. B. ( 2000 ) J. Biol. Chem. 275 , 6894-6900 ] .

Using <protein>purified proteins</protein> , we have prepared a five-protein heterocomplex assembly system consisting of two proteins essential for heterocomplex assembly- <protein>hsp90</protein> and <protein>hsp70</protein> -and three proteins that act as co-chaperones to enhance assembly- <protein>Hop</protein> , <protein>hsp40</protein> , <protein>p23</protein> [ Morishima , Y. , Kanelakis , K. C. , Silverstein , A. M. , Dittmar , K. D. , Estrada , L. , and Pratt , W. B. ( 2000 ) J. Biol. Chem. 275 , 6894-6900 ] .


The hsp70 co-chaperone Hip has been recovered in receptor.hsp90 heterocomplexes at an intermediate stage of assembly in reticulocyte lysate , and Hip is also thought to be an intrinsic component of the assembly machinery .

The <protein>hsp70 co-chaperone Hip</protein> has been recovered in <protein>receptor.hsp90 heterocomplexes</protein> at an intermediate stage of assembly in reticulocyte lysate , and <protein>Hip</protein> is also thought to be an intrinsic component of the assembly machinery .


Here we show that immunodepletion of Hip from reticulocyte lysate or addition of high levels of Hip to the purified five-protein system does not affect GR.hsp90 heterocomplex assembly or the activation of steroid binding activity that occurs with assembly .

Here we show that immunodepletion of <protein>Hip</protein> from reticulocyte lysate or addition of high levels of <protein>Hip</protein> to the purified five-protein system does not affect GR.hsp90 heterocomplex assembly or the activation of steroid binding activity that occurs with assembly .


Despite the fact that Hip does not affect assembly , it is recovered in GR.hsp90 heterocomplexes assembled by both systems .

Despite the fact that <protein>Hip</protein> does not affect assembly , it is recovered in <protein>GR.hsp90 heterocomplexes</protein> assembled by both systems .


In the five-protein system , Hip prevents inhibition of assembly by the hsp70 co-chaperone BAG-1 , and cotransfection of Hip with BAG-1 opposes BAG-1 reduction of steroid binding activity in COS cells .

In the five-protein system , <protein>Hip</protein> prevents inhibition of assembly by the <protein>hsp70 co-chaperone BAG-1</protein> , and cotransfection of <protein>Hip</protein> with <protein>BAG-1</protein> opposes <protein>BAG-1</protein> reduction of steroid binding activity in <cell_line>COS cells</cell_line> .


We conclude that Hip is not a component of the assembly machinery but that it could play a regulatory role in opposition to BAG-1 .

We conclude that <protein>Hip</protein> is not a component of the assembly machinery but that it could play a regulatory role in opposition to <protein>BAG-1</protein> .


Cutting edge : STAT6-deficient mice have enhanced tumor immunity to primary and metastatic mammary carcinoma .


STAT4 and STAT6 are essential for the development of CD4 ( + ) Th1 and Th2 development , respectively .

<protein>STAT4</protein> and <protein>STAT6</protein> are essential for the development of CD4 ( + ) Th1 and Th2 development , respectively .


Tumor immunologists have hypothesized that Th1 cells are critical in tumor immunity because they facilitate differentiation of CD8 ( + ) T cells , which are potent anti-tumor effectors .

Tumor immunologists have hypothesized that <cell_type>Th1 cells</cell_type> are critical in tumor immunity because they facilitate differentiation of <cell_type>CD8 ( + ) T cells</cell_type> , which are potent <cell_type>anti-tumor effectors</cell_type> .


We have used STAT4 ( -/- ) and STAT6 ( -/- ) mice to test this hypothesis .


BALB/c and knockout mice were challenged in the mammary gland with the highly malignant and spontaneously metastatic BALB/c-derived 4T1 mammary carcinoma .


Primary tumor growth and metastatic disease are reduced in STAT6 ( -/- ) mice relative to BALB/c and STAT4 ( -/- ) mice .


Ab depletions demonstrate that the effect is mediated by CD8 ( + ) T cells , and immunized STAT6 ( -/- ) mice have higher levels of 4T1-specific CTL than BALB/c or STAT4 ( -/- ) mice .

Ab depletions demonstrate that the effect is mediated by <cell_type>CD8 ( + ) T cells</cell_type> , and immunized STAT6 ( -/- ) mice have higher levels of <cell_type>4T1-specific CTL</cell_type> than BALB/c or STAT4 ( -/- ) mice .


Surprisingly , Th1 or Th2 cells are not involved , because CD4 depletion does not diminish the anti-tumor effect .

Surprisingly , <cell_type>Th1 or Th2 cells</cell_type> are not involved , because CD4 depletion does not diminish the anti-tumor effect .


Therefore , deletion of the STAT6 gene facilitates development of potent anti-tumor immunity via a CD4 ( + ) -independent pathway .

Therefore , deletion of the <dna>STAT6 gene</dna> facilitates development of potent anti-tumor immunity via a CD4 ( + ) -independent pathway .


Activation of oncogenic transcription factor AP-1 in T cells infected with human T cell leukemia virus type 1 .

Activation of <protein>oncogenic transcription factor AP-1</protein> in <cell_type>T cells</cell_type> infected with human T cell leukemia virus type 1 .


Human T cell leukemia virus type 1 ( HTLV-1 ) Tax protein transforms primary human T cells in vitro .

Human T cell leukemia virus type 1 ( HTLV-1 ) <protein>Tax protein</protein> transforms <cell_type>primary human T cells</cell_type> in vitro .


We previously showed that Tax induces the expression of various family members of the transcription factor AP-1 such as c-Jun , JunD , c-Fos , and Fra-1 at the mRNA level in T cells .

We previously showed that <protein>Tax</protein> induces the expression of various family members of the <protein>transcription factor AP-1</protein> such as <protein>c-Jun</protein> , <protein>JunD</protein> , <protein>c-Fos</protein> , and <protein>Fra-1</protein> at the mRNA level in <cell_type>T cells</cell_type> .


In this study , we have examined the ability of Tax to activate transcription through the AP-1-binding site ( AP-1 site ) .

In this study , we have examined the ability of <protein>Tax</protein> to activate transcription through the <dna>AP-1-binding site</dna> ( <dna>AP-1 site</dna> ) .


A transient transfection study showed that Tax can activate transcription through the AP-1-binding site in a human T cell line , whereas any combination of AP-1 proteins did so much less than Tax , indicating that the activation of the AP-1 site by Tax may require a mechanism other than the induction of AP-1 mRNA .

A transient transfection study showed that <protein>Tax</protein> can activate transcription through the <dna>AP-1-binding site</dna> in a <cell_line>human T cell line</cell_line> , whereas any combination of <protein>AP-1 proteins</protein> did so much less than <protein>Tax</protein> , indicating that the activation of the <dna>AP-1 site</dna> by <protein>Tax</protein> may require a mechanism other than the induction of <rna>AP-1 mRNA</rna> .


Fresh peripheral blood leukemia cells of all surveyed ATL patients displayed constitutive AP-1 DNA-binding activity , whereas no normal individuals did .

<cell_type>Fresh peripheral blood leukemia cells</cell_type> of all surveyed ATL patients displayed constitutive AP-1 DNA-binding activity , whereas no normal individuals did .


However , the HTLV-1 genes , including tax , are not significantly expressed in fresh leukemia cells from ATL patients .

However , the <dna>HTLV-1 genes</dna> , including <dna>tax</dna> , are not significantly expressed in fresh <cell_type>leukemia cells</cell_type> from ATL patients .


Our present results suggest that activation of AP-1 occurs through Tax-dependent and -independent mechanisms in HTLV-1-infected T cells , which may play some roles in dysregulated phenotypes of HTLV-1-infected cells .

Our present results suggest that activation of <protein>AP-1</protein> occurs through Tax-dependent and -independent mechanisms in HTLV-1-infected <cell_type>T cells</cell_type> , which may play some roles in dysregulated phenotypes of <cell_type>HTLV-1-infected cells</cell_type> .


2 , 2 ' , 4 , 6 , 6'-pentachlorobiphenyl induces apoptosis in human monocytic cells .

2 , 2 ' , 4 , 6 , 6'-pentachlorobiphenyl induces apoptosis in <cell_type>human monocytic cells</cell_type> .


Polychlorinatedbiphenyls ( PCBs ) are a group of persistent and widely dispersed environmental pollutants , some of which may be immunotoxic .


In the present study , we investigated the effect of PCBs on immune system by assessing apoptotic cell death in human monocytic U937 cells .

In the present study , we investigated the effect of PCBs on immune system by assessing apoptotic cell death in <cell_line>human monocytic U937 cells</cell_line> .


Among the various congeners tested , 2 , 2 ' , 4 , 6 , 6'-pentachlorobiphenyl ( PeCB ) , a highly ortho-substituted congener , specifically induced DNA fragmentation , a hallmark of apoptosis , while the other examined di- , tri- , tetra- , and pentachlorobiphenyls did not .


To further study the 2 , 2 ' , 4 , 6 , 6'-PeCB-induced cell death , various features of apoptosis were examined .


2 , 2 ' , 4 , 6 , 6'-PeCB caused a decrease in cell viability and induced cellular morphologic features characteristic of apoptosis such as chromatin aggregation and apoptotic bodies .


In addition , caspase-3 , an executioner of apoptosis , was activated and its substrate , poly ( ADP-ribose ) polymerase ( PARP ) , was cleaved during 2 , 2 ' , 4 , 6 , 6'-PeCB-induced apoptosis .

In addition , <protein>caspase-3</protein> , an executioner of apoptosis , was activated and its substrate , <protein>poly ( ADP-ribose ) polymerase</protein> ( <protein>PARP</protein> ) , was cleaved during 2 , 2 ' , 4 , 6 , 6'-PeCB-induced apoptosis .


In contrast , 3 , 3 ' , 4 , 4 ' , 5-PeCB , a congener of coplanar structure , as well as 2 , 3 , 7 , 8-TCDD did not induce apoptosis in these human monocytic cells , although they potently induced CYP 1A1 in human hepatoma Hep G2 cells .

In contrast , 3 , 3 ' , 4 , 4 ' , 5-PeCB , a congener of coplanar structure , as well as 2 , 3 , 7 , 8-TCDD did not induce apoptosis in these <cell_type>human monocytic cells</cell_type> , although they potently induced <protein>CYP 1A1</protein> in <cell_line>human hepatoma Hep G2 cells</cell_line> .


Taken together , the data indicate that 2 , 2 ' , 4 , 6 , 6'-PeCB induces apoptosis in human monocytic cells through a mechanism that is independent of the arylhydrocarbon receptor .

Taken together , the data indicate that 2 , 2 ' , 4 , 6 , 6'-PeCB induces apoptosis in <cell_type>human monocytic cells</cell_type> through a mechanism that is independent of the <protein>arylhydrocarbon receptor</protein> .


This suggests a possibly separate mechanism by which PCBs cause immunosuppression .


Effects of deregulated Raf activation on integrin , cytokine-receptor expression and the induction of apoptosis in hematopoietic cells .

Effects of deregulated Raf activation on <protein>integrin</protein> , cytokine-receptor expression and the induction of apoptosis in <cell_type>hematopoietic cells</cell_type> .


The effects of deregulated Raf activation on the growth and differentiation of hematopoietic cells were investigated .

The effects of deregulated Raf activation on the growth and differentiation of <cell_type>hematopoietic cells</cell_type> were investigated .


The cytokine-dependent murine myeloid FDC-P1 and human erythroleukemic TF-1 cell lines were transformed to grow in response to deregulated Raf expression in the absence of exogenous cytokines .

The <cell_line>cytokine-dependent murine myeloid FDC-P1</cell_line> and <cell_line>human erythroleukemic TF-1 cell lines</cell_line> were transformed to grow in response to deregulated Raf expression in the absence of <protein>exogenous cytokines</protein> .


The conditionally active Raf proteins were regulated by beta-estradiol as cDNAs containing the Raf catalytic , but lacking negative-regulatory domains , were ligated to the hormone binding domain of the estrogen receptor ( deltaRaf : ER ) .

The conditionally active <protein>Raf proteins</protein> were regulated by beta-estradiol as <dna>cDNAs</dna> containing the <protein>Raf catalytic</protein> , but lacking <protein>negative-regulatory domains</protein> , were ligated to the <protein>hormone binding domain</protein> of the <protein>estrogen receptor</protein> ( <protein>deltaRaf : ER</protein> ) .


Continuous deltaRaf expression prevented apoptosis in the absence of exogenous cytokines and altered the morphology of the FD/deltaRaf : ER cells as they grew in large aggregated masses ( > 100 cells ) whereas the parental cytokine-dependent FDC-P1 cells grew in smaller grape-like clusters ( < 10 cells ) .

Continuous <protein>deltaRaf</protein> expression prevented apoptosis in the absence of <protein>exogenous cytokines</protein> and altered the morphology of the <cell_type>FD/deltaRaf : ER cells</cell_type> as they grew in large aggregated masses ( > 100 cells ) whereas the <cell_line>parental cytokine-dependent FDC-P1 cells</cell_line> grew in smaller grape-like clusters ( < 10 cells ) .


FD/deltaRaf-1 : ER cells growing in response to Raf activation displayed decreased levels of the Mac-2 and Mac-3 molecules on their cell surface .

<cell_line>FD/deltaRaf-1 : ER cells</cell_line> growing in response to Raf activation displayed decreased levels of the <protein>Mac-2 and Mac-3 molecules</protein> on their <cell_type>cell surface</cell_type> .


In contrast , when these cells were cultured in IL-3 , higher levels of these adhesion molecules were detected .

In contrast , when these cells were cultured in <protein>IL-3</protein> , higher levels of these <protein>adhesion molecules</protein> were detected .


Expression of activated Raf oncoproteins also abrogated cytokine dependency and prevented apoptosis of TF-1 cells .

Expression of activated <protein>Raf oncoproteins</protein> also abrogated cytokine dependency and prevented apoptosis of <cell_line>TF-1 cells</cell_line> .


Moreover , the differentiation status of these Raf-responsive cells was more immature upon Raf activation as culture with the differentiation-inducing agent phorbol 12 myristate 13-acetate ( PMA ) and beta-estradiol resulted in decreased levels of the CD11b and CD18 integrin molecules on the cell surface .

Moreover , the differentiation status of these <cell_type>Raf-responsive cells</cell_type> was more immature upon Raf activation as culture with the differentiation-inducing agent phorbol 12 myristate 13-acetate ( PMA ) and beta-estradiol resulted in decreased levels of the <protein>CD11b and CD18 integrin molecules</protein> on the <cell_type>cell surface</cell_type> .


In contrast when the Raf-responsive cells were induced to differentiate with PMA and GM-CSF , in the absence of deltaRaf : ER activation , increased levels of the CD11b and CD18 molecules were detected .

In contrast when the <cell_type>Raf-responsive cells</cell_type> were induced to differentiate with PMA and <protein>GM-CSF</protein> , in the absence of <protein>deltaRaf : ER</protein> activation , increased levels of the <protein>CD11b and CD18 molecules</protein> were detected .


Retinoic acid ( RA ) inhibited 3H-thymidine incorporation in response to GM-CSF .

Retinoic acid ( RA ) inhibited 3H-thymidine incorporation in response to <protein>GM-CSF</protein> .


Interestingly , Raf activation counterbalanced the inhibition of DNA synthesis caused by RA but not PMA .


Thus deregulated Raf expression can alter cytokine dependency , integrin expression and the stage of differentiation .


These Raf-responsive cell lines will be useful in elucidating the roles of the MAP kinase cascade on hematopoietic cell differentiation and malignant transformation

These <cell_line>Raf-responsive cell lines</cell_line> will be useful in elucidating the roles of the MAP kinase cascade on <cell_type>hematopoietic cell</cell_type> differentiation and malignant transformation


Cyclic AMP activates p38 mitogen-activated protein kinase in Th2 cells : phosphorylation of GATA-3 and stimulation of Th2 cytokine gene expression .

Cyclic AMP activates <protein>p38 mitogen-activated protein kinase</protein> in <cell_type>Th2 cells</cell_type> : phosphorylation of <protein>GATA-3</protein> and stimulation of <cell_type>Th2</cell_type> cytokine gene expression .


cAMP is an important second messenger with immunomodulatory properties .


Elevation of intracellular cAMP in T cells , induced by agents such as IL-1alpha or PGs , inhibits T cell activation .

Elevation of intracellular cAMP in <cell_type>T cells</cell_type> , induced by agents such as <protein>IL-1alpha</protein> or <protein>PGs</protein> , inhibits T cell activation .


In effector T cells , an increase in the level of intracellular cAMP inhibits cytokine production in Th1 cells but stimulates cytokine production in Th2 cells .

In effector <cell_type>T cells</cell_type> , an increase in the level of intracellular cAMP inhibits <protein>cytokine</protein> production in <cell_type>Th1 cells</cell_type> but stimulates <protein>cytokine</protein> production in <cell_type>Th2 cells</cell_type> .


Here we report that cAMP-induced effects in Th2 cells occur independently of the protein kinase A pathway , which is the major mediator of cAMP-induced signaling events in most cell types .

Here we report that cAMP-induced effects in <cell_type>Th2 cells</cell_type> occur independently of the <protein>protein kinase A</protein> pathway , which is the major mediator of cAMP-induced signaling events in most cell types .


Instead , cAMP stimulates activation of p38 mitogen-activated protein kinase in Th2 cells .

Instead , cAMP stimulates activation of <protein>p38 mitogen-activated protein kinase</protein> in <cell_type>Th2 cells</cell_type> .


This appears to be a Th2 -selective event because cAMP barely increased p38 phosphorylation in Th1 cells .

This appears to be a <cell_type>Th2</cell_type> -selective event because cAMP barely increased <protein>p38</protein> phosphorylation in <cell_type>Th1 cells</cell_type> .


We show that in Th2 cells , cAMP promotes the production of both IL-5 and IL-13 , which play distinct but critical roles in asthma pathogenesis .

We show that in <cell_type>Th2 cells</cell_type> , cAMP promotes the production of both <protein>IL-5</protein> and <protein>IL-13</protein> , which play distinct but critical roles in asthma pathogenesis .


Our data also show that cAMP causes increased phosphorylation of the transcription factor GATA-3 , which we have shown is a critical regulator of Th2 cytokine gene expression and , in turn , of airway inflammation in mice .

Our data also show that cAMP causes increased phosphorylation of the <protein>transcription factor GATA-3</protein> , which we have shown is a critical regulator of <cell_type>Th2</cell_type> cytokine gene expression and , in turn , of airway inflammation in mice .


Thus , Th2 -specific GATA-3 expression and p38 mitogen-activated protein kinase activation together provide a molecular basis for the differential effects of cAMP in the two T helper cell subsets .

Thus , <cell_type>Th2</cell_type> -specific <protein>GATA-3</protein> expression and <protein>p38 mitogen-activated protein kinase</protein> activation together provide a molecular basis for the differential effects of cAMP in the two <cell_type>T helper cell subsets</cell_type> .


Characterization of IL-4 and IL-13 signals dependent on the human IL-13 receptor alpha chain 1 : redundancy of requirement of tyrosine residue for STAT3 activation .

Characterization of <protein>IL-4</protein> and <protein>IL-13</protein> signals dependent on the <protein>human IL-13 receptor alpha chain 1</protein> : redundancy of requirement of tyrosine residue for STAT3 activation .


IL-4 and IL-13 are pleiotropic cytokines whose biological activities overlap with each other .

<protein>IL-4</protein> and <protein>IL-13</protein> are <protein>pleiotropic cytokines</protein> whose biological activities overlap with each other .


IL-13 receptor alpha chain 1 ( IL-13R alpha 1 ) is necessary for binding to IL-13 , and the heterodimer composed of IL-13R alpha 1 and IL-4R alpha chain transduces IL-13 and IL-4 signals ; however , the functional mapping of the intracellular domain of IL-13R alpha 1 is not fully understood .

<protein>IL-13 receptor alpha chain 1</protein> ( <protein>IL-13R alpha 1</protein> ) is necessary for binding to <protein>IL-13</protein> , and the heterodimer composed of <protein>IL-13R alpha 1</protein> and <protein>IL-4R alpha chain</protein> transduces <protein>IL-13</protein> and <protein>IL-4</protein> signals ; however , the functional mapping of the <protein>intracellular domain</protein> of <protein>IL-13R alpha 1</protein> is not fully understood .


In this study , we constructed wild and mutated types of human IL-13R alpha 1 , and analyzed IL-4 and IL-13 signals using an IL-13R alpha 1 -transfected human B cell line .

In this study , we constructed wild and mutated types of <protein>human IL-13R alpha 1</protein> , and analyzed <protein>IL-4</protein> and <protein>IL-13</protein> signals using an <protein>IL-13R alpha 1</protein> -transfected <cell_line>human B cell line</cell_line> .


Expression of IL-13R alpha 1 evoked STAT3 activation by IL-4 and IL-13 , and in stimulated human B cells , on which IL-13R alpha 1 was highly expressed , IL-4 and IL-13 induced STAT3 activation .

Expression of <protein>IL-13R alpha 1</protein> evoked <protein>STAT3</protein> activation by <protein>IL-4</protein> and <protein>IL-13</protein> , and in stimulated <cell_type>human B cells</cell_type> , on which <protein>IL-13R alpha 1</protein> was highly expressed , <protein>IL-4</protein> and <protein>IL-13</protein> induced <protein>STAT3</protein> activation .


Replacement of the two tyrosine residues completely abolished STAT3 activation , although replacing either tyrosine residue alone retained it .

Replacement of the two tyrosine residues completely abolished <protein>STAT3</protein> activation , although replacing either tyrosine residue alone retained it .


Furthermore , we found that the Box1 region and the C-terminal tail of IL-13R alpha 1 were critical for binding to Tyk2 , and activation of Jak1 , Tyk2 , the insulin receptor substrate-1 and STAT6 respectively .

Furthermore , we found that the <protein>Box1 region</protein> and the <protein>C-terminal tail</protein> of <protein>IL-13R alpha 1</protein> were critical for binding to <protein>Tyk2</protein> , and activation of <protein>Jak1</protein> , <protein>Tyk2</protein> , the <protein>insulin receptor substrate-1</protein> and <protein>STAT6</protein> respectively .


These results suggest that STAT3 activation is involved with IL-4 and IL-13 signals in human B cells along with the activation of STAT6 , and that there is a unique sequence in IL-13R alpha 1 to activate STAT3 .

These results suggest that <protein>STAT3</protein> activation is involved with <protein>IL-4</protein> and <protein>IL-13</protein> signals in <cell_type>human B cells</cell_type> along with the activation of <protein>STAT6</protein> , and that there is a unique sequence in <protein>IL-13R alpha 1</protein> to activate <protein>STAT3</protein> .


Functional uncoupling of the Janus kinase 3-Stat5 pathway in malignant growth of human T cell leukemia virus type 1-transformed human T cells .

Functional uncoupling of the Janus kinase 3-Stat5 pathway in malignant growth of human T cell leukemia virus type 1-transformed <cell_type>human T cells</cell_type> .


Human T cell leukemia virus type 1 ( HTLV-1 ) transforms cytokine -dependent T lymphocytes and causes adult T cell leukemia .

Human T cell leukemia virus type 1 ( HTLV-1 ) transforms <protein>cytokine</protein> -dependent <cell_type>T lymphocytes</cell_type> and causes adult T cell leukemia .


Janus tyrosine kinase ( Jak ) 3 and transcription factors Stat5a and Stat5b are essential for the proliferation of normal T cells and are constitutively hyperactivated in both HTLV-1-transformed human T cell lines and lymphocytes isolated from HTLV-1-infected patients ; therefore , a critical role for the Jak3-Stat5 pathway in the progression of this disease has been postulated .

<protein>Janus tyrosine kinase ( Jak ) 3</protein> and <protein>transcription factors</protein> <protein>Stat5a</protein> and <protein>Stat5b</protein> are essential for the proliferation of <cell_type>normal T cells</cell_type> and are constitutively hyperactivated in both <cell_line>HTLV-1-transformed human T cell lines</cell_line> and <cell_type>lymphocytes</cell_type> isolated from HTLV-1-infected patients ; therefore , a critical role for the Jak3-Stat5 pathway in the progression of this disease has been postulated .


We recently reported that tyrphostin AG-490 selectively blocked IL-2 activation of Jak3/Stat5 and growth of murine T cell lines .

We recently reported that tyrphostin AG-490 selectively blocked IL-2 activation of <protein>Jak3/Stat5</protein> and growth of <cell_line>murine T cell lines</cell_line> .


Here we demonstrate that disruption of Jak3/Stat5a/b signaling with AG-490 ( 50 & mgr ; M ) blocked the proliferation of primary human T lymphocytes , but paradoxically failed to inhibit the proliferation of HTLV-1-transformed human T cell lines , HuT-102 and MT-2 .

Here we demonstrate that disruption of Jak3/Stat5a/b signaling with AG-490 ( 50 & mgr ; M ) blocked the proliferation of <cell_type>primary human T lymphocytes</cell_type> , but paradoxically failed to inhibit the proliferation of <cell_line>HTLV-1-transformed human T cell lines</cell_line> , <cell_line>HuT-102</cell_line> and <cell_line>MT-2</cell_line> .


Structural homologues of AG-490 also inhibited the proliferation of primary human T cells , but not HTLV-1-infected cells .

Structural homologues of AG-490 also inhibited the proliferation of <cell_type>primary human T cells</cell_type> , but not <cell_type>HTLV-1-infected cells</cell_type> .


Disruption of constitutive Jak3/Stat5 activation by AG-490 was demonstrated by inhibition of 1 ) tyrosine phosphorylation of Jak3 , Stat5a ( Tyr ( 694 ) ) , and Stat5b ( Tyr ( 699 ) ) ; 2 ) serine phosphorylation of Stat5a ( Ser ( 726 ) ) as determined by a novel phosphospecific Ab ; and 3 ) Stat5a/b DNA binding to the Stat5-responsive beta-casein promoter .

Disruption of constitutive Jak3/Stat5 activation by AG-490 was demonstrated by inhibition of 1 ) tyrosine phosphorylation of <protein>Jak3</protein> , <protein>Stat5a</protein> ( Tyr ( 694 ) ) , and <protein>Stat5b</protein> ( Tyr ( 699 ) ) ; 2 ) serine phosphorylation of <protein>Stat5a</protein> ( Ser ( 726 ) ) as determined by a novel <protein>phosphospecific Ab</protein> ; and 3 ) Stat5a/b DNA binding to the <dna>Stat5-responsive beta-casein promoter</dna> .


In contrast , AG-490 had no effect on DNA binding by p50/p65 components of NF-kappaB , a transcription factor activated by the HTLV-1-encoded phosphoprotein , Tax .

In contrast , AG-490 had no effect on DNA binding by <protein>p50/p65 components</protein> of <protein>NF-kappaB</protein> , a <protein>transcription factor</protein> activated by the <protein>HTLV-1-encoded phosphoprotein , Tax</protein> .


Collectively , these data suggest that the Jak3-Stat5 pathway in HTLV-1-transformed T cells has become functionally redundant for proliferation .

Collectively , these data suggest that the Jak3-Stat5 pathway in <cell_type>HTLV-1-transformed T cells</cell_type> has become functionally redundant for proliferation .


Reversal of this functional uncoupling may be required before Jak3/Stat5 inhibitors will be useful in the treatment of this malignancy .


The Epstein-Barr virus promoter initiating B-cell transformation is activated by RFX proteins and the B-cell-specific activator protein BSAP/Pax5 .

The <dna>Epstein-Barr virus promoter</dna> initiating B-cell transformation is activated by <protein>RFX proteins</protein> and the <protein>B-cell-specific activator protein BSAP/Pax5</protein> .


Epstein-Barr virus ( EBV ) -induced B-cell growth transformation , a central feature of the virus ' strategy for colonizing the human B-cell system , requires full virus latent gene expression and is initiated by transcription from the viral promoter Wp .

Epstein-Barr virus ( EBV ) -induced <cell_type>B-cell</cell_type> growth transformation , a central feature of the virus ' strategy for colonizing the human B-cell system , requires full virus latent gene expression and is initiated by transcription from the <dna>viral promoter Wp</dna> .


Interestingly , when EBV accesses other cell types , this growth-transforming program is not activated .


The present work focuses on a region of Wp which in reporter assays confers B-cell -specific activity .

The present work focuses on a region of <dna>Wp</dna> which in reporter assays confers <cell_type>B-cell</cell_type> -specific activity .


Bandshift studies indicate that this region contains three factor binding sites , termed sites B , C , and D , in addition to a previously characterized CREB site .

Bandshift studies indicate that this region contains three factor binding sites , termed <dna>sites B , C , and D</dna> , in addition to a previously characterized <dna>CREB site</dna> .


Here we show that site C binds members of the ubiquitously expressed RFX family of proteins , notably RFX1 , RFX3 , and the associated factor MIBP1 , whereas sites B and D both bind the B-cell-specific activator protein BSAP/Pax5 .

Here we show that <dna>site C</dna> binds members of the ubiquitously expressed <protein>RFX family of proteins</protein> , notably <protein>RFX1</protein> , <protein>RFX3</protein> , and the associated factor <protein>MIBP1</protein> , whereas <dna>sites B and D</dna> both bind the <protein>B-cell-specific activator protein BSAP/Pax5</protein> .


In reporter assays with mutant Wp constructs , the loss of factor binding to any one of these sites severely impaired promoter activity in B cells , while the wild-type promoter could be activated in non-B cells by ectopic BSAP expression .

In reporter assays with <dna>mutant Wp constructs</dna> , the loss of factor binding to any one of these sites severely impaired promoter activity in <cell_type>B cells</cell_type> , while the <dna>wild-type promoter</dna> could be activated in <cell_type>non-B cells</cell_type> by ectopic BSAP expression .


We suggest that Wp regulation by BSAP helps to ensure the B-cell specificity of EBV 's growth-transforming function .

We suggest that <dna>Wp</dna> regulation by <protein>BSAP</protein> helps to ensure the <cell_type>B-cell</cell_type> specificity of EBV 's growth-transforming function .


Activation of the Lck tyrosine protein kinase by the Herpesvirus saimiri tip protein involves two binding interactions .

Activation of the <protein>Lck tyrosine protein kinase</protein> by the Herpesvirus saimiri <protein>tip protein</protein> involves two binding interactions .


The Tip protein of Herpesvirus saimiri strain 484C binds to and activates the Lck tyrosine protein kinase .

The <protein>Tip protein</protein> of Herpesvirus saimiri strain 484C binds to and activates the <protein>Lck tyrosine protein kinase</protein> .


Two sequences in the Tip protein were previously shown to be involved in binding to Lck .

Two sequences in the <protein>Tip protein</protein> were previously shown to be involved in binding to <protein>Lck</protein> .


A proline-rich region , residues 132-141 , binds to the SH3 domain of the Lck protein .

A <protein>proline-rich region</protein> , residues 132-141 , binds to the <protein>SH3 domain</protein> of the <protein>Lck protein</protein> .


We show here that the other Lck-binding domain , residues 104-113 , binds to the carboxyl-terminal half of Lck and that this binding does not require the Lck SH3 domain .

We show here that the other <protein>Lck-binding domain</protein> , residues 104-113 , binds to the <protein>carboxyl-terminal half</protein> of <protein>Lck</protein> and that this binding does not require the <protein>Lck SH3 domain</protein> .


Mutated Tip containing only one functional Lck-binding domain can bind stably to Lck , although not as strongly as wild-type Tip .

Mutated <protein>Tip</protein> containing only one functional <protein>Lck-binding domain</protein> can bind stably to <protein>Lck</protein> , although not as strongly as <protein>wild-type Tip</protein> .


Interaction of Tip with Lck through either Lck-binding domain increases the activity of Lck in vivo .

Interaction of <protein>Tip</protein> with <protein>Lck</protein> through either <protein>Lck-binding domain</protein> increases the activity of <protein>Lck</protein> in vivo .


Simultaneous binding of both domains is required for maximal activation of Lck .

Simultaneous binding of both domains is required for maximal activation of <protein>Lck</protein> .


The transient expression of Tip in T cells was found to stimulate both Stat3 -dependent and NF-AT -dependent transcription .

The transient expression of <protein>Tip</protein> in <cell_type>T cells</cell_type> was found to stimulate both <protein>Stat3</protein> -dependent and <protein>NF-AT</protein> -dependent transcription .


Mutant forms of Tip lacking one or the other of the two Lck-binding domains retained the ability to stimulate Stat3 -dependent transcription .

Mutant forms of <protein>Tip</protein> lacking one or the other of the two <protein>Lck-binding domains</protein> retained the ability to stimulate <protein>Stat3</protein> -dependent transcription .


Tip lacking the proline-rich Lck-binding domain exhibited almost wild-type activity in this assay .

<protein>Tip</protein> lacking the proline-rich <protein>Lck-binding domain</protein> exhibited almost wild-type activity in this assay .


In contrast , ablation of either Lck-binding domain abolished the ability of Tip to stimulate NF-AT -dependent transcription .

In contrast , ablation of either <protein>Lck-binding domain</protein> abolished the ability of <protein>Tip</protein> to stimulate <protein>NF-AT</protein> -dependent transcription .


Full biological activity of Tip , therefore , appears to require both Lck-binding domains .

Full biological activity of <protein>Tip</protein> , therefore , appears to require both <protein>Lck-binding domains</protein> .


Accumulation of RXR alpha during activation of cycling human T lymphocytes : modulation of RXRE transactivation function by mitogen-activated protein kinase pathways .

Accumulation of <protein>RXR alpha</protein> during activation of cycling <cell_type>human T lymphocytes</cell_type> : modulation of RXRE transactivation function by mitogen-activated protein kinase pathways .


We have previously reported that the activation of resting human immature peripheral blood T ( PBT ) lymphocytes is associated with the loss of retinoid X receptor alpha ( RXRalpha ) expression .

We have previously reported that the activation of resting <cell_type>human immature peripheral blood T ( PBT ) lymphocytes</cell_type> is associated with the loss of <protein>retinoid X receptor alpha</protein> ( <protein>RXRalpha</protein> ) expression .


In the present study , we have demonstrated that , unlike resting cells , activation of cycling human mature PBT lymphocytes , and T lymphocyte leukemia cell lines is accompanied by the accumulation of RXRalpha mRNA and protein .

In the present study , we have demonstrated that , unlike resting cells , activation of <cell_type>cycling human mature PBT lymphocytes</cell_type> , and <cell_line>T lymphocyte leukemia cell lines</cell_line> is accompanied by the accumulation of <protein>RXRalpha</protein> mRNA and protein .


Interestingly , cyclosporin A further augmented RXRalpha expression , indicating the involvement of calcineurin pathways in the process .

Interestingly , cyclosporin A further augmented <protein>RXRalpha</protein> expression , indicating the involvement of calcineurin pathways in the process .


9-cis retinoic acid inhibited the accumulation , suggesting that retinoids can regulate the synthesis of their own receptors during T cell activation .


Transfection analysis in Jurkat cells , using RXRE-dependent reporter assays , showed that RXRalpha accumulated during T cell activation was transcriptionally inactive .

Transfection analysis in <cell_line>Jurkat cells</cell_line> , using RXRE-dependent reporter assays , showed that <protein>RXRalpha</protein> accumulated during T cell activation was transcriptionally inactive .


To investigate the mechanism of such inhibition , the role of two mitogen-activated protein kinase pathways , c-Jun N-terminal kinase ( JNK ) and extracellular signal-regulated kinase ( ERK ) , in modulating RXRE-dependent transcription , was explored .

To investigate the mechanism of such inhibition , the role of two mitogen-activated protein kinase pathways , <protein>c-Jun N-terminal kinase</protein> ( <protein>JNK</protein> ) and <protein>extracellular signal-regulated kinase</protein> ( <protein>ERK</protein> ) , in modulating RXRE-dependent transcription , was explored .


The expression of constitutively active MAP/ERK kinase kinase 1 ( MEKK1 ) inhibited RXRE-dependent transcription , whereas dominant negative MEKK1 increased the transcription , indicating the involvement of JNK signaling pathways in the process .

The expression of constitutively active <protein>MAP/ERK kinase kinase 1</protein> ( <protein>MEKK1</protein> ) inhibited RXRE-dependent transcription , whereas <protein>dominant negative MEKK1</protein> increased the transcription , indicating the involvement of <protein>JNK</protein> signaling pathways in the process .


In contrast , expression of constitutively active MEK1 , which activates ERK pathway , enhanced RXRE-dependent activation .

In contrast , expression of <protein>constitutively active MEK1</protein> , which activates <protein>ERK</protein> pathway , enhanced RXRE-dependent activation .


When both were activated simultaneously , JNK pathway was dominant over ERK pathway and resulted in inhibition of RXRE-mediated transcription .

When both were activated simultaneously , <protein>JNK</protein> pathway was dominant over <protein>ERK</protein> pathway and resulted in inhibition of RXRE-mediated transcription .


These data demonstrate a dual regulatory control of RXRalpha expression during the activation of resting and cycling T lymphocytes and indicate a dynamic balance between JNK and ERK pathways in modulating RXRE-mediated transactivation .

These data demonstrate a dual regulatory control of <protein>RXRalpha</protein> expression during the activation of <cell_type>resting and cycling T lymphocytes</cell_type> and indicate a dynamic balance between JNK and ERK pathways in modulating RXRE-mediated transactivation .


The proteasome regulates receptor-mediated endocytosis of interleukin-2 .

The <protein>proteasome</protein> regulates receptor-mediated endocytosis of <protein>interleukin-2</protein> .


Recent studies have increasingly implicated the proteasome in the regulation of cell surface receptors .

Recent studies have increasingly implicated the <protein>proteasome</protein> in the regulation of <protein>cell surface receptors</protein> .


In the present study , we investigated the role of the proteasome for ligand-dependent endocytosis and degradation of the interleukin-2 ( IL-2 ) -interleukin-2 receptor ( IL-2R ) complex .

In the present study , we investigated the role of the <protein>proteasome</protein> for ligand-dependent endocytosis and degradation of the <protein>interleukin-2 ( IL-2 ) -interleukin-2 receptor ( IL-2R ) complex</protein> .


Proteasome inhibitors impaired internalization of IL-2.IL-2R and prevented the lysosomal degradation of this cytokine .

Proteasome inhibitors impaired internalization of <protein>IL-2.IL-2R</protein> and prevented the lysosomal degradation of this <protein>cytokine</protein> .


Based on time-course studies , proteasome activity is primarily required after initial endocytosis of the IL-2.IL-2R .

Based on time-course studies , <protein>proteasome</protein> activity is primarily required after initial endocytosis of the <protein>IL-2.IL-2R</protein> .


Proteasome function was also necessary for the lysosomal degradation of IL-2 internalized by IL-2R that were comprised of cytoplasmic tailless beta- or gamma c-subunits , suggesting that the target protein for the proteasome is independent of either the cytoplasmic tail of the IL-2R beta- or gamma c-subunits and their associated signaling components .

Proteasome function was also necessary for the lysosomal degradation of <protein>IL-2</protein> internalized by <protein>IL-2R</protein> that were comprised of <protein>cytoplasmic tailless</protein> <protein>beta- or gamma c-subunits</protein> , suggesting that the target protein for the <protein>proteasome</protein> is independent of either the <protein>cytoplasmic tail</protein> of the <protein>IL-2R</protein> <protein>beta- or gamma c-subunits</protein> and their associated signaling components .


Therefore , a functional proteasome is required for optimal endocytosis of the IL-2R/ligand complex and is essential for the subsequent lysosomal degradation of IL-2 , possibly by regulating trafficking to the lysosome .

Therefore , a functional <protein>proteasome</protein> is required for optimal endocytosis of the <protein>IL-2R/ligand complex</protein> and is essential for the subsequent lysosomal degradation of <protein>IL-2</protein> , possibly by regulating trafficking to the lysosome .


Functional characterization of the two alternative promoters of human p45 NF-E2 gene .

Functional characterization of the two alternative promoters of <dna>human p45 NF-E2 gene</dna> .


OBJECTIVE : The transcription factor NF-E2 , a heterodimeric protein complex composed of p45 and small Maf family proteins , is considered crucial for the proper differentiation of erythrocytes and megakaryocytes in vivo .

OBJECTIVE : The <protein>transcription factor NF-E2</protein> , a <protein>heterodimeric protein complex</protein> composed of <protein>p45</protein> and small <protein>Maf family proteins</protein> , is considered crucial for the proper differentiation of <cell_type>erythrocytes</cell_type> and <cell_type>megakaryocytes</cell_type> in vivo .


We report the results of studies aimed at understanding the regulatory mechanisms controlling p45 gene expression in erythroid cells .

We report the results of studies aimed at understanding the regulatory mechanisms controlling <dna>p45 gene</dna> expression in <cell_type>erythroid cells</cell_type> .


MATERIALS AND METHODS : Human p45 mRNAs have two alternative isoforms , aNF-E2 and fNF-E2 , and these isoforms are transcribed from the alternative promoters .

MATERIALS AND METHODS : <rna>Human p45 mRNAs</rna> have two alternative isoforms , <rna>aNF-E2</rna> and <rna>fNF-E2</rna> , and these isoforms are transcribed from the <dna>alternative promoters</dna> .


We investigated lineage-specific expression of both isomers in human erythroid and megakaryocytic cells by reverse transcriptase polymerase chain reaction or Northern blot analysis .

We investigated lineage-specific expression of both isomers in human <cell_type>erythroid and megakaryocytic cells</cell_type> by reverse transcriptase polymerase chain reaction or Northern blot analysis .


For functional characterization of both promoters , plasmids in which reporter genes were placed under the control of a series of truncated or mutated promoter fragments were transfected to human hematopoietic cell lines .

For functional characterization of both promoters , plasmids in which <dna>reporter genes</dna> were placed under the control of a series of truncated or mutated <dna>promoter fragments</dna> were transfected to <cell_line>human hematopoietic cell lines</cell_line> .


RESULTS : When CD34 ( + ) cells isolated from human cord blood were induced to unilineage erythroid or megakaryocytic differentiation in liquid suspension culture , both transcripts , although barely detected at day 0 , were induced in both erythroid and megakaryocytic cultures .

RESULTS : When <cell_type>CD34 ( + ) cells</cell_type> isolated from human cord blood were induced to unilineage erythroid or megakaryocytic differentiation in liquid suspension culture , both transcripts , although barely detected at day 0 , were induced in both erythroid and megakaryocytic cultures .


fNF-E2 mRNA was found to be more abundant in erythroid cells than megakaryocytic cells at day 7 of culture .

<rna>fNF-E2 mRNA</rna> was found to be more abundant in <cell_type>erythroid cells</cell_type> than <cell_type>megakaryocytic cells</cell_type> at day 7 of culture .


Although both isomers were expressed in human erythroid-megakaryocytic cell lines , megakaryocytic maturation with loss of erythroid phenotype induced by phorbol 12-myristate 13-acetate ( PMA ) resulted in exclusive downregulation of fNF-E2 , suggesting that fNF-E2 promoter is more erythroid specific .

Although both isomers were expressed in <cell_line>human erythroid-megakaryocytic cell lines</cell_line> , megakaryocytic maturation with loss of erythroid phenotype induced by phorbol 12-myristate 13-acetate ( PMA ) resulted in exclusive downregulation of <rna>fNF-E2</rna> , suggesting that <dna>fNF-E2 promoter</dna> is more erythroid specific .


Functional analysis of fNF-E2 promoter showed that the promoter is active only in erythroid-megakaryocytic cells and that the double GATA sit e in the proximal region is necessary for its efficient activity .

Functional analysis of <dna>fNF-E2 promoter</dna> showed that the promoter is active only in <cell_type>erythroid-megakaryocytic cells</cell_type> and that the <dna>double GATA sit</dna> e in the proximal region is necessary for its efficient activity .


CONCLUSION : These results suggest that GATA proteins , which govern the differentiation of erythroid lineage cells , are required for full promoter activity of the p45 gene .

CONCLUSION : These results suggest that <protein>GATA proteins</protein> , which govern the differentiation of <cell_type>erythroid lineage cells</cell_type> , are required for full promoter activity of the <dna>p45 gene</dna> .


Transcriptional activation of heme oxygenase-1 and its functional significance in acetaminophen-induced hepatitis and hepatocellular injury in the rat .

Transcriptional activation of <dna>heme oxygenase-1</dna> and its functional significance in acetaminophen-induced hepatitis and hepatocellular injury in the rat .


BACKGROUND/AIM : Glutathione depletion contributes to acetaminophen hepatotoxicity and is known to induce the oxidative stress reactant heme oxygenase-1 .

BACKGROUND/AIM : Glutathione depletion contributes to acetaminophen hepatotoxicity and is known to induce the oxidative stress reactant <protein>heme oxygenase-1</protein> .


The metabolites of the heme oxygenase pathway , biliverdin , carbon monoxide , and iron may modulate acetaminophen toxicity .


The aim of this study was to assess cell-type specific expression of heme oxygenase-1 and its impact on liver injury and microcirculatory disturbances in a model of acetaminophen-induced hepatitis .

The aim of this study was to assess cell-type specific expression of <dna>heme oxygenase-1</dna> and its impact on liver injury and microcirculatory disturbances in a model of acetaminophen-induced hepatitis .


METHODS : Gene expression of heme oxygenase-1 was studied by Northern- and Western analysis as well as immunohistochemistry .

METHODS : Gene expression of <dna>heme oxygenase-1</dna> was studied by Northern- and Western analysis as well as immunohistochemistry .


The time course of heme oxygenase-1 and -2 , cytokine-induced neutrophil chemoattractant-1 , and intercellular adhesion molecule-1 was studied by Northern analysis .

The time course of <protein>heme oxygenase-1 and -2</protein> , <protein>cytokine-induced neutrophil chemoattractant-1</protein> , and <protein>intercellular adhesion molecule-1</protein> was studied by Northern analysis .


DNA-binding activity of nuclear factor-kappaB was determined by electrophoretic mobility shift assay .

DNA-binding activity of <protein>nuclear factor-kappaB</protein> was determined by electrophoretic mobility shift assay .


Sinusoidal perfusion and leukocyte-endothelial interactions were assessed by intravital microscopy .


RESULTS : Acetaminophen caused a moderate sinusoidal perfusion failure ( -15 % ) and infiltration of neutrophils along with activation of nuclear factor-kappaB and intercellular adhesion molecule-1 and cytokine-induced neutrophil chemoattractant-1 mRNAs .

RESULTS : Acetaminophen caused a moderate sinusoidal perfusion failure ( -15 % ) and infiltration of <cell_type>neutrophils</cell_type> along with activation of <protein>nuclear factor-kappaB</protein> and <protein>intercellular adhesion molecule-1</protein> and <protein>cytokine-induced neutrophil chemoattractant-1</protein> mRNAs .


Induction of heme oxygenase-1 mRNA and protein ( approximately 30-fold ) in hepatocytes and non-parenchymal cells paralleled the inflammatory response .

Induction of <protein>heme oxygenase-1</protein> mRNA and protein ( approximately 30-fold ) in <cell_type>hepatocytes</cell_type> and <cell_type>non-parenchymal cells</cell_type> paralleled the inflammatory response .


Blockade of heme oxygenase activity with tin-protoporphyrin-IX abrogated acetaminophen-induced hepatic neutrophil accumulation and nuclear factor-kappaB activation , but failed to affect sinusoidal perfusion and liver injury .

Blockade of heme oxygenase activity with tin-protoporphyrin-IX abrogated acetaminophen-induced <cell_type>hepatic neutrophil</cell_type> accumulation and <protein>nuclear factor-kappaB</protein> activation , but failed to affect sinusoidal perfusion and liver injury .


CONCLUSIONS : The inflammatory response associated with acetaminophen hepatotoxicity is modulated by the parallel induction of the heme oxygenase-1 gene .

CONCLUSIONS : The inflammatory response associated with acetaminophen hepatotoxicity is modulated by the parallel induction of the <dna>heme oxygenase-1 gene</dna> .


However , heme oxygenase-1 has no permissive effect on sinusoidal perfusion and does not affect liver injury in this model .

However , <dna>heme oxygenase-1</dna> has no permissive effect on sinusoidal perfusion and does not affect liver injury in this model .


These data argue against a central role of nuclear factor-kappaB activation and neutrophil infiltration as perpetuating factors of liver injury in acetaminophen toxicity .

These data argue against a central role of <protein>nuclear factor-kappaB</protein> activation and neutrophil infiltration as perpetuating factors of liver injury in acetaminophen toxicity .


Tumor necrosis factor-alpha -induced proliferation requires synthesis of granulocyte-macrophage colony-stimulating factor .

<protein>Tumor necrosis factor-alpha</protein> -induced proliferation requires synthesis of <protein>granulocyte-macrophage colony-stimulating factor</protein> .


OBJECTIVE : Tumor necrosis factor- alpha ( TNF-alpha ) induces a variety of cellular responses , some of them being at least seemingly contradictory .

OBJECTIVE : <protein>Tumor necrosis factor- alpha</protein> ( <protein>TNF-alpha</protein> ) induces a variety of cellular responses , some of them being at least seemingly contradictory .


Thus , we set out to find differences in the modes of proliferative and apoptotic responses to TNF- alpha .

Thus , we set out to find differences in the modes of proliferative and apoptotic responses to <protein>TNF- alpha</protein> .


MATERIALS AND METHODS : We screened a panel of acute myeloid leukemia-derived cell lines for TNF- alpha -responsiveness .

MATERIALS AND METHODS : We screened a panel of <cell_line>acute myeloid leukemia-derived cell lines</cell_line> for <protein>TNF- alpha</protein> -responsiveness .


In two lines ( OCI-AML-1 , OCI-AML-11 ) , TNF- alpha acted as an apoptotic agent ; in others ( HU-3 , M-07e , TF-1 ) , it had the opposite effect , preventing apoptosis and inducing proliferation .

In two lines ( <cell_line>OCI-AML-1</cell_line> , <cell_line>OCI-AML-11</cell_line> ) , <protein>TNF- alpha</protein> acted as an apoptotic agent ; in others ( <cell_line>HU-3</cell_line> , <cell_line>M-07e</cell_line> , <cell_line>TF-1</cell_line> ) , it had the opposite effect , preventing apoptosis and inducing proliferation .


Direct and indirect signaling mechanisms , including NF-kappaB activation and cytokine synthesis , were analyzed .

Direct and indirect signaling mechanisms , including <protein>NF-kappaB</protein> activation and cytokine synthesis , were analyzed .


RESULTS : All cell lines tested expressed TNF- alpha receptors I and II and responded to TNF- alpha by upregulation of intercellular adhesion molecule-1 .

RESULTS : All cell lines tested expressed <protein>TNF- alpha receptors I and II</protein> and responded to <protein>TNF- alpha</protein> by upregulation of <protein>intercellular adhesion molecule-1</protein> .


In contrast to granulocyte-macrophage colony-stimulating factor ( GM-CSF ) , TNF- alpha did not activate the MAP kinase and p70S6 kinase pathways .

In contrast to <protein>granulocyte-macrophage colony-stimulating factor</protein> ( <protein>GM-CSF</protein> ) , <protein>TNF- alpha</protein> did not activate the <protein>MAP kinase</protein> and p70S6 kinase pathways .


Nevertheless , inhibitors of these pathways clearly reduced the TNF-alpha -induced cell growth , indicating that TNF- alpha-proliferative cells produced a growth factor that induced proliferation upon stimulation of the above pathways .

Nevertheless , inhibitors of these pathways clearly reduced the <protein>TNF-alpha</protein> -induced cell growth , indicating that <cell_type>TNF- alpha-proliferative cells</cell_type> produced a growth factor that induced proliferation upon stimulation of the above pathways .


Anti-GM-CSF antibodies inhibited the TNF-alpha -induced growth , suggesting the presence of an autocrine loop for cell proliferation mediated by GM-CSF .

<protein>Anti-GM-CSF antibodies</protein> inhibited the <protein>TNF-alpha</protein> -induced growth , suggesting the presence of an autocrine loop for cell proliferation mediated by <protein>GM-CSF</protein> .


Supporting this notion , TNF-alpha -induced upregulation of GM-CSF mRNA levels and protein secretion in the TNF-alpha -proliferative , but not in the TNF-alpha-apoptotic cell lines .

Supporting this notion , <protein>TNF-alpha</protein> -induced upregulation of <rna>GM-CSF mRNA</rna> levels and protein secretion in the <protein>TNF-alpha</protein> -proliferative , but not in the <cell_line>TNF-alpha-apoptotic cell lines</cell_line> .


CONCLUSION : These data identify GM-CSF synthesis as an early and essential step in TNF- alpha-induced proliferation .

CONCLUSION : These data identify <protein>GM-CSF</protein> synthesis as an early and essential step in TNF- alpha-induced proliferation .


We show for the first time that TNF-alpha-treated cell lines producing no or only minimal amounts of GM-CSF demonstrate an apoptotic phenotype , while cell lines with high GM-CSF expression rates can escape from growth arrest or even apoptosis .

We show for the first time that <cell_line>TNF-alpha-treated cell lines</cell_line> producing no or only minimal amounts of <protein>GM-CSF</protein> demonstrate an apoptotic phenotype , while cell lines with high <protein>GM-CSF</protein> expression rates can escape from growth arrest or even apoptosis .


In this context , we discuss arguments pointing at NF-kappaB as regulator of GM-CSF synthesis and thus indirectly as regulator for the escape of TNF-alpha -induced apoptosis

In this context , we discuss arguments pointing at <protein>NF-kappaB</protein> as regulator of <protein>GM-CSF</protein> synthesis and thus indirectly as regulator for the escape of <protein>TNF-alpha</protein> -induced apoptosis


Glucocorticoid receptor content of T lymphocytes : evidence for heterogeneity .

<protein>Glucocorticoid receptor</protein> content of <cell_type>T lymphocytes</cell_type> : evidence for heterogeneity .


Glucocorticoid receptors were measured in T lymphocytes that were isolated from peripheral blood by either nylon wool filtration or E-rosette sedimentation .

<protein>Glucocorticoid receptors</protein> were measured in <cell_type>T lymphocytes</cell_type> that were isolated from peripheral blood by either nylon wool filtration or E-rosette sedimentation .


T cells isolated by nylon wool filtration specifically bind 6.7 +/- 0.2 fmol of dexamethasone per million cells ( equivalent to 4000 +/- 200 receptors per cell ) , whereas T cells isolated by E-rosette sedimentation bind 12.0 +/- 0.7 fmol of dexamethasone per million cells ( equivalent to 7200 +/- 400 receptors per cell ) .

<cell_type>T cells</cell_type> isolated by nylon wool filtration specifically bind 6.7 +/- 0.2 fmol of dexamethasone per million cells ( equivalent to 4000 +/- 200 receptors per cell ) , whereas <cell_type>T cells</cell_type> isolated by E-rosette sedimentation bind 12.0 +/- 0.7 fmol of dexamethasone per million cells ( equivalent to 7200 +/- 400 receptors per cell ) .


This difference in the amount of dexamethasone bound by the two T cell preparations was significant ( p less than .001 ) and was present immediately after cell isolation .


The binding affinities of the different T cell preparations for dexamethasone were similar .

The binding affinities of the different <cell_line>T cell preparations</cell_line> for dexamethasone were similar .


T cells that are isolated by a combination of nylon wool filtration followed by E-rosette sedimentation bind the same amount of dexamethasone as T cells isolated by nylon wool filtration alone .

T cells that are isolated by a combination of nylon wool filtration followed by E-rosette sedimentation bind the same amount of dexamethasone as <cell_type>T cells</cell_type> isolated by nylon wool filtration alone .


T cells isolated by a combination of E-rosette sedimentation following by nylon wool filtration bind less dexamethasone than do T cells isolated by E-rosette sedimentation alone .

<cell_type>T cells</cell_type> isolated by a combination of E-rosette sedimentation following by nylon wool filtration bind less dexamethasone than do <cell_type>T cells</cell_type> isolated by E-rosette sedimentation alone .


These findings suggest that T cells are heterogeneous with respect to their quantity of glucocorticoid receptors .

These findings suggest that <cell_type>T cells</cell_type> are heterogeneous with respect to their quantity of <protein>glucocorticoid receptors</protein> .


Isolation of T cells by E-rosette sedimentation enriches for T cells that have a greater number of glucocorticoid receptors , and isolation of T cells by nylon wool filtration enriches for T cells that have a lesser number of glucocorticoid receptors .

Isolation of <cell_type>T cells</cell_type> by E-rosette sedimentation enriches for <cell_type>T cells</cell_type> that have a greater number of <protein>glucocorticoid receptors</protein> , and isolation of <cell_type>T cells</cell_type> by nylon wool filtration enriches for <cell_type>T cells</cell_type> that have a lesser number of <protein>glucocorticoid receptors</protein> .


Glucocorticoid receptors and glucocorticoid sensitivity of human leukemic cells .

<protein>Glucocorticoid receptors</protein> and glucocorticoid sensitivity of <cell_type>human leukemic cells</cell_type> .


We have established optimal conditions for the measurement of glucocorticoid receptors ( GR ) in human white cells using a whole-cell binding assay with [ 3H ] dexamethasone as the ligand , and the subsequent determination of the GR content in normal human lymphocytes and in leukemic cells of patients with various forms of acute and chronic leukemia .

We have established optimal conditions for the measurement of <protein>glucocorticoid receptors</protein> ( <protein>GR</protein> ) in <cell_type>human white cells</cell_type> using a whole-cell binding assay with [ 3H ] dexamethasone as the ligand , and the subsequent determination of the <protein>GR</protein> content in <cell_type>normal human lymphocytes</cell_type> and in <cell_type>leukemic cells</cell_type> of patients with various forms of acute and chronic leukemia .


A number of leukemia cell lines in continuous culture were also subjected to the GR assay , and the results were correlated with the sensitivity of these cell lines to glucocorticoid steroids in vitro .

A number of <cell_line>leukemia cell lines</cell_line> in continuous culture were also subjected to the <protein>GR</protein> assay , and the results were correlated with the sensitivity of these <cell_line>cell lines</cell_line> to glucocorticoid steroids in vitro .


The GR content of normal human lymphocytes amounted to 4 , 850 +/- 1 , 340 ( mean +/- SD ) receptors/cell .

The <protein>GR</protein> content of <cell_type>normal human lymphocytes</cell_type> amounted to 4 , 850 +/- 1 , 340 ( mean +/- SD ) receptors/cell .


The mean equilibrium dissociation constant ( KD ) of the interaction of [ 3H ] dexamethasone with the GR was 1.2 x 10 ( -8 ) M .

The mean equilibrium dissociation constant ( KD ) of the interaction of [ 3H ] dexamethasone with the <protein>GR</protein> was 1.2 x 10 ( -8 ) M .


Steroidal compounds with a known glucocorticoid potency effectively competed for the binding , whereas steroids devoid of glucocorticoid activity ( e.g. estradiol-17 beta and testosterone ) were ineffective .


The GR content of the blast cells obtained from eight patients suffering from acute leukemia and four patients with a blast crisis of chronic myelocytic leukemia was found to be highly variable ( 3 , 230-29 , 900 receptors/cell ) , while the lymphocytes of six patients with chronic lymphatic leukemia contained a rather stable GR content ( 2 , 930-5 , 120 receptors/cell ) , which was comparable with that of normal lymphocytes .

The <protein>GR</protein> content of the <cell_type>blast cells</cell_type> obtained from eight patients suffering from acute leukemia and four patients with a blast crisis of chronic myelocytic leukemia was found to be highly variable ( 3 , 230-29 , 900 receptors/cell ) , while the <cell_type>lymphocytes</cell_type> of six patients with chronic lymphatic leukemia contained a rather stable <protein>GR</protein> content ( 2 , 930-5 , 120 receptors/cell ) , which was comparable with that of <cell_type>normal lymphocytes</cell_type> .


GR was identified in all the 12 malignant continuous white cell lines studied .

<protein>GR</protein> was identified in all the 12 <cell_line>malignant continuous white cell lines</cell_line> studied .


Large cells contained more GR than the smaller ones .

Large cells contained more <protein>GR</protein> than the smaller ones .


There was no apparent correlation between the GR concentration and the sensitivity of the cells in vitro to glucocorticoids as judged by [ 3H ] thymidine incorporation studies .

There was no apparent correlation between the <protein>GR</protein> concentration and the sensitivity of the cells in vitro to glucocorticoids as judged by [ 3H ] thymidine incorporation studies .


Distribution of the surface markers in the leukemic cell lines did not relate to the GR concentration .

Distribution of the surface markers in the <cell_line>leukemic cell lines</cell_line> did not relate to the <protein>GR</protein> concentration .


We conclude that the presence of GR is probably a universal feature of the leukemic cells , and , from a clinical standpoint , probably does not alone imply steroid responsiveness .

We conclude that the presence of <protein>GR</protein> is probably a universal feature of the <cell_type>leukemic cells</cell_type> , and , from a clinical standpoint , probably does not alone imply steroid responsiveness .


Evidence for a steroid receptor in rheumatoid synovial tissue cells .

Evidence for a <protein>steroid receptor</protein> in <cell_type>rheumatoid synovial tissue cells</cell_type> .


One mechanism by which glucocorticoids could exert their anti-inflammatory action is via rapidly saturable , stereo-specific cytoplasmic protein receptors .

One mechanism by which glucocorticoids could exert their anti-inflammatory action is via rapidly saturable , <protein>stereo-specific cytoplasmic protein receptors</protein> .


This report is of an investigation into such a possibility in synovial cells .

This report is of an investigation into such a possibility in <cell_type>synovial cells</cell_type> .


Synovium , obtained from knee joints of rheumatoid patients undergoing surgery , was incubated with clostridiopeptidase A and trypsin-EDTA to obtain cell suspensions .

Synovium , obtained from knee joints of rheumatoid patients undergoing surgery , was incubated with <protein>clostridiopeptidase A</protein> and <protein>trypsin-EDTA</protein> to obtain cell suspensions .


These , together with cells obtained from synovial fluid aspirated from patients with rheumatoid arthritis , were identified by electron microscopy .


Duplicate samples of these cell suspensions were incubated with increasing concentrations of H3Dexamethasone ( 1 x 10 ( -10 ) M-1 x 10 ( -9 ) M ) for 30 minutes at 37 degrees C .


Analysis of the proportion of steroid bound to whole cells showed evidence for specific , rapidly saturable , receptors in the cells obtained from synovial tissue , but this was not found in synovial fluid cells .

Analysis of the proportion of steroid bound to <cell_type>whole cells</cell_type> showed evidence for specific , rapidly saturable , receptors in the cells obtained from synovial tissue , but this was not found in <cell_type>synovial fluid cells</cell_type> .


Electron micrographs showed that cells obtained from synovial tissue consisted of synovial fibroblast - and macrophage-types , lymphocytes , monocytes and macrophages .

Electron micrographs showed that cells obtained from synovial tissue consisted of <cell_type>synovial fibroblast</cell_type> - and <cell_type>macrophage-types</cell_type> , <cell_type>lymphocytes</cell_type> , <cell_type>monocytes</cell_type> and <cell_type>macrophages</cell_type> .


Polymorphonuclear leucocytes appeared to be absent .

<cell_type>Polymorphonuclear leucocytes</cell_type> appeared to be absent .


However , in synovial fluid cell type polymorphonuclear leucocytes were the predominant cell type .

However , in <cell_type>synovial fluid cell type polymorphonuclear leucocytes</cell_type> were the predominant cell type .