Here we demonstrate that both Smad6 and Smad7 are human bone morphogenetic protein-2 ( hBMP-2 ) -inducible antagonists of hBMP-2 -induced growth arrest and apoptosis in mouse B cell hybridoma HS-72 cells .

Here we demonstrate that both <protein>Smad6</protein> and <protein>Smad7</protein> are <protein>human bone morphogenetic protein-2</protein> ( <protein>hBMP-2</protein> ) -inducible antagonists of <protein>hBMP-2</protein> -induced growth arrest and apoptosis in <cell_line>mouse B cell hybridoma</cell_line> <cell_line>HS-72 cells</cell_line> .


Moreover , we confirmed that the ectopic expressions of Smad6 and Smad7 inhibited the hBMP-2 -induced Smad1/Smad5 phosphorylation .

Moreover , we confirmed that the ectopic expressions of <protein>Smad6</protein> and <protein>Smad7</protein> inhibited the <protein>hBMP-2</protein> -induced <protein>Smad1/Smad5</protein> phosphorylation .


We previously reported that Smad7 is an activin A-inducible antagonist of activin A-induced growth arrest and apoptosis in HS-72 cells .

We previously reported that <protein>Smad7</protein> is an activin A-inducible antagonist of activin A-induced growth arrest and apoptosis in <cell_line>HS-72 cells</cell_line> .


Interestingly , although mRNA expression of Smad6 was induced by activin A in HS-72 cells , Smad6 showed no antagonistic effect on activin A-induced growth arrest and apoptosis .

Interestingly , although mRNA expression of <protein>Smad6</protein> was induced by activin A in <cell_line>HS-72 cells</cell_line> , <protein>Smad6</protein> showed no antagonistic effect on activin A-induced growth arrest and apoptosis .


Moreover , we found that the ectopic expression of Smad7 , but not Smad6 , inhibited the activin A-induced Smad2 phosphorylation in HS-72 cells .

Moreover , we found that the ectopic expression of <protein>Smad7</protein> , but not <protein>Smad6</protein> , inhibited the activin A-induced Smad2 phosphorylation in <cell_line>HS-72 cells</cell_line> .


Thus , Smad6 and Smad7 exhibit differential inhibitory effects in bone morphogenetic protein-2- and activin A-mediated signaling in B lineage cells .

Thus , <protein>Smad6</protein> and <protein>Smad7</protein> exhibit differential inhibitory effects in bone morphogenetic protein-2- and activin A-mediated signaling in <cell_type>B lineage cells</cell_type> .


Retinoic acid induces apoptosis of human CD34+ hematopoietic progenitor cells : involvement of retinoic acid receptors and retinoid X receptors depends on lineage commitment of the hematopoietic progenitor cells .

Retinoic acid induces apoptosis of <cell_type>human CD34+ hematopoietic progenitor cells</cell_type> : involvement of <protein>retinoic acid receptors</protein> and <protein>retinoid X receptors</protein> depends on lineage commitment of the <cell_type>hematopoietic progenitor cells</cell_type> .


Retinoids are bifunctional regulators of growth and differentiation of hematopoietic cells .

Retinoids are bifunctional regulators of growth and differentiation of <cell_type>hematopoietic cells</cell_type> .


In this study we explored the effects of retinoic acid ( RA ) on apoptosis of human CD34+ hematopoietic progenitor cells isolated from normal bone marrow .

In this study we explored the effects of retinoic acid ( RA ) on apoptosis of <cell_type>human CD34+ hematopoietic progenitor cells</cell_type> isolated from normal bone marrow .


RA ( 100 nM ) induced an increase in the percentage of dead cells from 24 % to 44 % at day 6 ( p < 0.05 , n = 6 ) as compared to control cells cultured in medium alone .

RA ( 100 nM ) induced an increase in the percentage of <cell_type>dead cells</cell_type> from 24 % to 44 % at day 6 ( p < 0.05 , n = 6 ) as compared to <cell_type>control cells</cell_type> cultured in medium alone .


The effect was dose dependent and appeared relatively late .


Significant differences were observed from day 4 onward .


Apoptosis , or programmed cell death , was demonstrated as the mode of cell death by using the TUNEL assay , which detects single strand nicks in DNA , or by the Nicoletti technique demonstrating a subdiploid population by DNA staining .


RA previously was found to inhibit granulocyte colony-stimulating factor -- and not granulocyte-macrophage colony-stimulating factor -- stimulated proliferation of CD34+ cells .

RA previously was found to inhibit <protein>granulocyte colony-stimulating factor</protein> -- and not <protein>granulocyte-macrophage colony-stimulating factor</protein> -- stimulated proliferation of <cell_type>CD34+ cells</cell_type> .


However , we found that RA opposed anti-apoptotic effects of G-CSF and GM-CSF on CD34+ cells ( G-CSF : 8 % dead cells at day 6 ; G-CSF + RA : 20 % ; GM-CSF : 12 % ; GM-CSF + RA : 27 % ) .

However , we found that RA opposed anti-apoptotic effects of <protein>G-CSF</protein> and <protein>GM-CSF</protein> on <cell_type>CD34+ cells</cell_type> ( <protein>G-CSF</protein> : 8 % <cell_type>dead cells</cell_type> at day 6 ; <protein>G-CSF</protein> + RA : 20 % ; <protein>GM-CSF</protein> : 12 % ; <protein>GM-CSF</protein> + RA : 27 % ) .


Moreover , RA induced apoptosis of CD34+ cells and CD34+CD71+ cells stimulated with erythropoietin .

Moreover , RA induced apoptosis of <cell_type>CD34+ cells</cell_type> and <cell_type>CD34+CD71+ cells</cell_type> stimulated with <protein>erythropoietin</protein> .


To explore the receptor signaling pathways involved in RA-induced apoptosis , we used selective ligands for retinoic acid receptors ( RARs ; RO13-7410 ) and retinoid X receptors ( RXRs ; RO 25-6603 ) .

To explore the receptor signaling pathways involved in RA-induced apoptosis , we used selective ligands for <protein>retinoic acid receptors</protein> ( RARs ; RO13-7410 ) and <protein>retinoid X receptors</protein> ( <protein>RXRs</protein> ; RO 25-6603 ) .


We found that RARs were involved in RA-mediated apoptosis of myeloid progenitor cells , whereas RARs as well as RXRs were involved in RA-mediated apoptosis of erythroid progenitor cells .

We found that <protein>RARs</protein> were involved in RA-mediated apoptosis of myeloid progenitor cells , whereas <protein>RARs</protein> as well as <protein>RXRs</protein> were involved in RA-mediated apoptosis of <cell_type>erythroid progenitor cells</cell_type> .


Suppressive effects of anti-inflammatory agents on human endothelial cell activation and induction of heat shock proteins .

Suppressive effects of anti-inflammatory agents on <cell_type>human endothelial cell</cell_type> activation and induction of <protein>heat shock proteins</protein> .


BACKGROUND : Studies from our laboratory have shown that the earliest stages of atherosclerosis may be mediated by an autoimmune reaction against heat shock protein 60 ( Hsp60 ) .

BACKGROUND : Studies from our laboratory have shown that the earliest stages of atherosclerosis may be mediated by an autoimmune reaction against <protein>heat shock protein 60</protein> ( <protein>Hsp60</protein> ) .


The interactions of Hsp60-specific T cells with arterial endothelial cells ( EC ) require expression of both Hsp60 and certain adhesion molecules shown to be induced simultaneously in EC by mechanical and other types of stress .

The interactions of <cell_line>Hsp60-specific T cells</cell_line> with arterial <cell_type>endothelial cells</cell_type> ( <cell_type>EC</cell_type> ) require expression of both <protein>Hsp60</protein> and certain <protein>adhesion molecules</protein> shown to be induced simultaneously in <cell_type>EC</cell_type> by mechanical and other types of stress .


Recently , it was shown that suppression of T cell-mediated immune responses by cyclosporin A ( CyA ) enhanced atherosclerotic lesion formation in mice .


In contrast , aspirin was found to lower the risk of myocardial infarction in men .


These conflicting observations may be due to different effects of anti-inflammatory agents on adhesion molecule and Hsp expression in EC , respectively .

These conflicting observations may be due to different effects of anti-inflammatory agents on adhesion molecule and Hsp expression in <cell_type>EC</cell_type> , respectively .


MATERIAL AND METHODS : In the present study , we analyzed the effects of CyA , aspirin , and indomethacin on T cell proliferation using a proliferation assay .


To explore the expression of adhesion molecules , monocyte chemoattractant protein-1 ( MCP-1 ) , and Hsp60 in human umbilical vein endothelial cells ( HUVECs ) , Northern blot analyses were used .

To explore the expression of <protein>adhesion molecules</protein> , <protein>monocyte chemoattractant protein-1</protein> ( <protein>MCP-1</protein> ) , and <protein>Hsp60</protein> in <cell_type>human umbilical vein endothelial cells</cell_type> ( <cell_type>HUVECs</cell_type> ) , Northern blot analyses were used .


To examine the activation status of the transcription factors nuclear factor kappaB ( NF-kappaB ) and heat shock factor-1 ( HSF-1 ) , electrophoretic mobility shift assays were performed .

To examine the activation status of the <protein>transcription factors</protein> <protein>nuclear factor kappaB</protein> ( <protein>NF-kappaB</protein> ) and <protein>heat shock factor-1</protein> ( <protein>HSF-1</protein> ) , electrophoretic mobility shift assays were performed .


RESULTS : With the exception of indomethacin , the used immunosuppressive and anti-inflammatory agents significantly inhibited T cell proliferation in response to influenza virus antigen in a dose-dependent manner .

RESULTS : With the exception of indomethacin , the used immunosuppressive and anti-inflammatory agents significantly inhibited T cell proliferation in response to <protein>influenza virus antigen</protein> in a dose-dependent manner .


Interestingly , CyA and indomethacin did not suppress tumor necrosis factor-alpha ( TNF-alpha ) -induced adhesion molecule expression on HUVECs , whereas aspirin had an inhibitory effect .

Interestingly , CyA and indomethacin did not suppress <protein>tumor necrosis factor-alpha</protein> ( <protein>TNF-alpha</protein> ) -induced adhesion molecule expression on <cell_type>HUVECs</cell_type> , whereas aspirin had an inhibitory effect .


These observations correlated with the modulation of NF-kappaB activity in EC .

These observations correlated with the modulation of <protein>NF-kappaB</protein> activity in <cell_type>EC</cell_type> .


All agents tested induced expression of Hsp60 6 hr after application .

All agents tested induced expression of <protein>Hsp60</protein> 6 hr after application .


In addition , aspirin and indomethacin , but not CyA , induced Hsp70 expression in HUVECs that correlated with induction of HSF-1 activity .

In addition , aspirin and indomethacin , but not CyA , induced <protein>Hsp70</protein> expression in <cell_type>HUVECs</cell_type> that correlated with induction of <protein>HSF-1</protein> activity .


CONCLUSION : Our results show that the tested agents ( except indomethacin ) are inhibitors of the T cell-mediated immune response , as expected , that aspirin is an effective suppressor of adhesion molecule expression , and that all three agents can induce Hsp60 in HUVECs .

CONCLUSION : Our results show that the tested agents ( except indomethacin ) are inhibitors of the T cell-mediated immune response , as expected , that aspirin is an effective suppressor of <protein>adhesion molecule</protein> expression , and that all three agents can induce <protein>Hsp60</protein> in <cell_type>HUVECs</cell_type> .


These data provide the molecular basis for the notion that ( 1 ) part of the anti-atherogenic effect of aspirin may be due to the prevention of the adhesion of sensitized T cells to stressed EC ; ( 2 ) that part of the atherosclerosis-promoting effect of CyA may be due to its potential as an inducer of Hsp60 expression and its inability to down-regulate adhesion molecule expression on EC ; and ( 3 ) that down-regulation of MCP-1 expression by aspirin may result in decreased recruitment of monocytes into the arterial intima beneath stressed EC .

These data provide the molecular basis for the notion that ( 1 ) part of the anti-atherogenic effect of aspirin may be due to the prevention of the adhesion of <cell_type>sensitized T cells</cell_type> to stressed <cell_type>EC</cell_type> ; ( 2 ) that part of the atherosclerosis-promoting effect of CyA may be due to its potential as an inducer of <protein>Hsp60</protein> expression and its inability to down-regulate <protein>adhesion molecule</protein> expression on <cell_type>EC</cell_type> ; and ( 3 ) that down-regulation of <protein>MCP-1</protein> expression by aspirin may result in decreased recruitment of <cell_type>monocytes</cell_type> into the arterial intima beneath stressed <cell_type>EC</cell_type> .


In vivo modulation of glucocorticoid receptor mRNA by inhaled fluticasone propionate in bronchial mucosa and blood lymphocytes in subjects with mild asthma .

In vivo modulation of <rna>glucocorticoid receptor mRNA</rna> by inhaled fluticasone propionate in bronchial mucosa and <cell_type>blood lymphocytes</cell_type> in subjects with mild asthma .


BACKGROUND : In vivo regulation of the glucocorticoid receptor ( GR ) by glucocorticoids provides a means of modulating sensitivity of targeted cells .

BACKGROUND : In vivo regulation of the <protein>glucocorticoid receptor</protein> ( <protein>GR</protein> ) by glucocorticoids provides a means of modulating sensitivity of targeted cells .


OBJECTIVE : We sought to determine the in vivo modulation of GR mRNA expression by fluticasone propionate ( FP ) in subjects with mild asthma .

OBJECTIVE : We sought to determine the in vivo modulation of <rna>GR mRNA</rna> expression by fluticasone propionate ( FP ) in subjects with mild asthma .


METHODS : Ten atopic asthmatic subjects were treated with FP 250 microg twice daily for 4 weeks .


Before and after treatment , the patients underwent fiberoptic bronchoscopy with endobronchial biopsy and sampling of venous blood for measurements of GR mRNA levels .

Before and after treatment , the patients underwent fiberoptic bronchoscopy with endobronchial biopsy and sampling of venous blood for measurements of <rna>GR mRNA</rna> levels .


A solution hybridization assay was used for quantitative analysis of GR mRNA .

A solution hybridization assay was used for quantitative analysis of <rna>GR mRNA</rna> .


In addition , a 24-hour urinary cortisol excretion and an adrenocorticotropic hormone test before and after treatment with FP were performed .


RESULTS : A high interindividual variation in GR mRNA expression was seen .

RESULTS : A high interindividual variation in <rna>GR mRNA</rna> expression was seen .


However , we detected a significant reduction of the GR mRNA levels in the endobronchial biopsy specimens after FP treatment ( 36.6 +/- 23.1 and 25.0 +/- 10.9 amol GR mRNA /microg RNA , respectively ; P < .01 ) .

However , we detected a significant reduction of the <rna>GR mRNA</rna> levels in the endobronchial biopsy specimens after FP treatment ( 36.6 +/- 23.1 and 25.0 +/- 10.9 amol <rna>GR mRNA</rna> /microg RNA , respectively ; P < .01 ) .


In the peripheral blood lymphocytes an even more striking downregulation of the GR by its cognate ligand was documented ( 30.3 +/- 26.5 and 8.8 +/- 5 amol GR mRNA /microg RNA , respectively ; P < .001 ) , possibly reflecting differences in glucocorticoid sensitivity between tissues .

In the peripheral <cell_type>blood lymphocytes</cell_type> an even more striking downregulation of the GR by its cognate ligand was documented ( 30.3 +/- 26.5 and 8.8 +/- 5 amol <rna>GR mRNA</rna> /microg RNA , respectively ; P < .001 ) , possibly reflecting differences in glucocorticoid sensitivity between tissues .


A small but significant reduction of the 24-hour urinary cortisol excretion was observed ( 233 +/- 109 and 157 +/- 66 nmol/L , respectively ; P < .01 ) , whereas the feedback regulation of glucocorticoid synthesis by means of the hypothalamic-pituitary-adrenal axis as assessed by the adrenocorticotropic hormone test remained normal after treatment with FP .


CONCLUSION : The results in this study confirm the potency of the inhaled corticosteroid FP and provide evidence for a considerable tissue-specific interindividual variation in the expression of the GR .

CONCLUSION : The results in this study confirm the potency of the inhaled corticosteroid FP and provide evidence for a considerable tissue-specific interindividual variation in the expression of the <protein>GR</protein> .


[ Corticoids and allergy ]


Inflammation is constantly observed in allergic reactions .


Corticosteroids are most effective in preventing the late phase of allergic reaction .


The action of glucocorticosteroids is mediated through glucocorticoid receptors present in the cellular cytoplasm .

The action of glucocorticosteroids is mediated through <protein>glucocorticoid receptors</protein> present in the cellular cytoplasm .


When activated , glucocorticoid receptors form a dimer and bind to DNA after migration into the nucleus .

When activated , <protein>glucocorticoid receptors</protein> form a <protein>dimer</protein> and bind to DNA after migration into the nucleus .


Interaction to DNA induces changes in the transcription rate , leading to either gene induction or gene repression .


Glucocorticoid receptors are also able to interact with transcriptional factors such as AP-1 ( activator protein-1 ) of NF-kappa B ( nuclear factor-kappa B ) .

Glucocorticoid receptors are also able to interact with transcriptional factors such as <protein>AP-1</protein> ( <protein>activator protein-1</protein> ) of <protein>NF-kappa B</protein> ( <protein>nuclear factor-kappa B</protein> ) .


Through these actions glucocorticosteroids are susceptible to modify functions of cells involved in the allergic inflammatory response .


They are in particular able to inhibit most of the pro-inflammatory functions of the eosinophils .

They are in particular able to inhibit most of the pro-inflammatory functions of the <cell_type>eosinophils</cell_type> .


Jeg-3 human choriocarcinoma-induced immunosuppression : downregulation of interleukin-2 , interleukin-2 receptor alpha-chain , and its Jak/Stat signaling pathway .

Jeg-3 human choriocarcinoma-induced immunosuppression : downregulation of <protein>interleukin-2</protein> , <protein>interleukin-2 receptor alpha-chain</protein> , and its <protein>Jak/Stat</protein> signaling pathway .


PROBLEM : The mechanisms of the immunosuppressive and immunosuppression-inducing capacities of Jeg-3 human choriocarcinoma cell line supernatants ( HCSs ) are not yet completely understood .

PROBLEM : The mechanisms of the immunosuppressive and immunosuppression-inducing capacities of <cell_line>Jeg-3 human choriocarcinoma cell line</cell_line> supernatants ( HCSs ) are not yet completely understood .


The influence on interleukin ( IL ) -2 , IL-4 and interferon ( IFN ) -gamma production ; IL-2 receptor ( IL-2R ) alpha - , beta - , and gamma-chain ; and the signaling pathway molecules Janus kinase ( Jak ) 1 , Jak3 , signal transducers and activators of transcription ( Stat ) 1 , Stat3 , and Stat5 should be investigated .

The influence on <protein>interleukin ( IL ) -2</protein> , <protein>IL-4</protein> and <protein>interferon ( IFN ) -gamma</protein> production ; <protein>IL-2 receptor ( IL-2R ) alpha</protein> - , <protein>beta</protein> - , and <protein>gamma-chain</protein> ; and the <protein>signaling pathway molecules</protein> <protein>Janus kinase</protein> <protein>( Jak ) 1</protein> , <protein>Jak3</protein> , signal transducers and <protein>activators of transcription</protein> <protein>( Stat ) 1</protein> , <protein>Stat3</protein> , and <protein>Stat5</protein> should be investigated .


METHOD OF STUDY : For assessment of IL production , whole peripheral venous blood from healthy donors was stimulated with phorbol-myristate-acetate and ionomycine .


Secretion of ILs was blocked with monensine .

Secretion of <protein>ILs</protein> was blocked with monensine .


Intracellular ILs were analyzed by flow cytometry .

Intracellular <protein>ILs</protein> were analyzed by flow cytometry .


For IL-2R and signaling pathway molecule analysis , peripheral blood lymphocytes were stimulated with phytohemagglutinin ( PHA ) .

For <protein>IL-2R</protein> and signaling pathway molecule analysis , peripheral <cell_type>blood lymphocytes</cell_type> were stimulated with <protein>phytohemagglutinin</protein> ( <protein>PHA</protein> ) .


IL-2R chains were measured by flow cytometry , and Jaks/Stats by sodium dodecyl sulfate polyacrylamide gel electrophoresis ( SDS-PAGE ) and Western blot .

IL-2R chains were measured by flow cytometry , and <protein>Jaks/Stats</protein> by sodium dodecyl sulfate polyacrylamide gel electrophoresis ( SDS-PAGE ) and Western blot .


RESULTS : Phorbol-myristate-acetate and ionomycine strongly increase the percent-age of IL-2+ cells ; an additional 50 % HCSs significantly suppresses the percentage to , or below the level of unstimulated cells .

RESULTS : Phorbol-myristate-acetate and ionomycine strongly increase the percent-age of <cell_line>IL-2+ cells</cell_line> ; an additional 50 % HCSs significantly suppresses the percentage to , or below the level of <cell_type>unstimulated cells</cell_type> .


IFN-gamma production is strongly decreased by HCSs in some cases , but not in others .


PHA stimulates IL-2R alpha- , beta- , and gamma-chain expression and their signaling pathway molecules Jak1 , Jak3 , Stat1 , Stat3 , and Stat5 .

<protein>PHA</protein> stimulates IL-2R alpha- , beta- , and gamma-chain expression and their <protein>signaling pathway molecules</protein> <protein>Jak1</protein> , <protein>Jak3</protein> , Stat1 , <protein>Stat3</protein> , and <protein>Stat5</protein> .


50 % HCS downregulates the alpha-chain and slightly upregulates the beta-chain .

50 % HCS downregulates the <protein>alpha-chain</protein> and slightly upregulates the <protein>beta-chain</protein> .


Jak1 , Jak3 , Stat1 , Stat3 , and Stat5 expression is suppressed approximately to , or below the level of unstimulated cells .

Jak1 , Jak3 , Stat1 , Stat3 , and Stat5 expression is suppressed approximately to , or below the level of <cell_type>unstimulated cells</cell_type> .


CONCLUSIONS : HCS forcefully blocks the production of IL-2 ; the IL-2R alpha-chain ; and Jak1 , Jak3 , Stat1 , Stat3 , and Stat5 expression .

CONCLUSIONS : HCS forcefully blocks the production of <protein>IL-2</protein> ; the <protein>IL-2R alpha-chain</protein> ; and Jak1 , Jak3 , Stat1 , Stat3 , and Stat5 expression .


The observed phenomena might be caused by downregulation of an IL-2R regulation gene , and might play a key role in the expansion of choriocarcinoma , and possibly in the survival of the fetal allograft .

The observed phenomena might be caused by downregulation of an <dna>IL-2R regulation gene</dna> , and might play a key role in the expansion of choriocarcinoma , and possibly in the survival of the fetal allograft .


Apoptosis-resistant T cells have a deficiency in NF-kappaB -mediated induction of Fas ligand transcription .

<cell_line>Apoptosis-resistant T cells</cell_line> have a deficiency in <protein>NF-kappaB</protein> -mediated induction of <protein>Fas ligand</protein> transcription .


Apoptosis induced through the TCR in CD4+ T cells is mostly mediated by the inducible expression of Fas ligand ( FasL ) as a primary event leading to the commitment to death .

Apoptosis induced through the <protein>TCR</protein> in <cell_type>CD4+ T cells</cell_type> is mostly mediated by the inducible expression of <protein>Fas ligand</protein> ( <protein>FasL</protein> ) as a primary event leading to the commitment to death .


To gain a better understanding of the transcriptional events that regulate this expression , we took advantage of our previously described mutant Jurkat cells .

To gain a better understanding of the transcriptional events that regulate this expression , we took advantage of our previously described <cell_line>mutant Jurkat cells</cell_line> .


These cells are deficient in FasL expression and apoptosis induced upon TCR triggering , although their cytokine ( IL-2 and IFN-gamma ) production is normal .

These cells are deficient in <protein>FasL</protein> expression and apoptosis induced upon <protein>TCR</protein> triggering , although their cytokine ( <protein>IL-2</protein> and <protein>IFN-gamma</protein> ) production is normal .


Here we show that both a FasL- and a consensus NF-kappaB- reporter construct are inefficiently induced in these cells compared to wild-type cells .

Here we show that both a <dna>FasL- and a consensus NF-kappaB- reporter construct</dna> are inefficiently induced in these cells compared to <cell_type>wild-type cells</cell_type> .


In addition , we demonstrate that the inducible transcriptional activity of the FasL reporter is abolished by specific inhibitors of NF-kappaB activation .

In addition , we demonstrate that the inducible transcriptional activity of the <dna>FasL reporter</dna> is abolished by specific inhibitors of <protein>NF-kappaB</protein> activation .


Thus , we could trace the deficit of the mutant cells to an inefficient NF-kappaB activation , evidencing a relevant role for NF-kappaB in the regulation of FasL expression in activated T cells .

Thus , we could trace the deficit of the <cell_type>mutant cells</cell_type> to an inefficient <protein>NF-kappaB</protein> activation , evidencing a relevant role for <protein>NF-kappaB</protein> in the regulation of <protein>FasL</protein> expression in <cell_type>activated T cells</cell_type> .


Furthermore , our results suggest that the induction of FasL versus cytokine gene expression is differentially sensitive to NF-kappaB deprivation .

Furthermore , our results suggest that the induction of <protein>FasL</protein> versus <dna>cytokine gene</dna> expression is differentially sensitive to <protein>NF-kappaB</protein> deprivation .


Decreased proteasome -mediated degradation in T cells from the elderly : A role in immune senescence .

Decreased <protein>proteasome</protein> -mediated degradation in <cell_type>T cells</cell_type> from the elderly : A role in immune senescence .


Induction of NFkappaB is a highly regulated process requiring phosphorylation , ubiquitination , and proteasome -mediated degradation of the cytosolic inhibitor IkappaBalpha .

Induction of <protein>NFkappaB</protein> is a highly regulated process requiring phosphorylation , ubiquitination , and <protein>proteasome</protein> -mediated degradation of the <protein>cytosolic inhibitor</protein> <protein>IkappaBalpha</protein> .


Analyses of the regulation of IkappaBalpha in TNF-alpha-treated T lymphocytes from young and elderly donors revealed severely compromised degradation of IkappaBalpha in T cells from the elderly .

Analyses of the regulation of <protein>IkappaBalpha</protein> in <cell_type>TNF-alpha-treated T lymphocytes</cell_type> from young and elderly donors revealed severely compromised degradation of <protein>IkappaBalpha</protein> in <cell_type>T cells</cell_type> from the elderly .


Examination of activation-induced phosphorylation and ubiquitination of IkappaBalpha did not demonstrate any significant age-related alterations .

Examination of activation-induced phosphorylation and ubiquitination of <protein>IkappaBalpha</protein> did not demonstrate any significant age-related alterations .


However , examination of proteasome activity in these T cells using fluorogenic peptide assays revealed a significant age-related decline in chymotryptic activity .

However , examination of <protein>proteasome</protein> activity in these <cell_type>T cells</cell_type> using fluorogenic peptide assays revealed a significant age-related decline in chymotryptic activity .


These results suggest that a decline in proteasome activity results in a failure to fully degrade IkappaBalpha in the elderly .

These results suggest that a decline in <protein>proteasome</protein> activity results in a failure to fully degrade <protein>IkappaBalpha</protein> in the elderly .


This failure to degrade IkappaBalpha may underlie both the observed decrease in NFkappaB induction and the IL-2 receptor expression in TNF-treated T cells during aging .

This failure to degrade <protein>IkappaBalpha</protein> may underlie both the observed decrease in <protein>NFkappaB</protein> induction and the <protein>IL-2</protein> receptor expression in <cell_line>TNF-treated T cells</cell_line> during aging .


Thus , decreased proteasome -mediated degradation may be central to immune dysfunction that accompanies aging .

Thus , decreased <protein>proteasome</protein> -mediated degradation may be central to immune dysfunction that accompanies aging .


Copyright 1999 Academic Press .


Inhibition of IL-4 -inducible gene expression in human monocytes by type I and type II interferons .

Inhibition of <protein>IL-4</protein> -inducible gene expression in <cell_type>human monocytes</cell_type> by <protein>type I and type II interferons</protein> .


The Th2-type cytokines , interleukin-4 ( IL-4 ) and interleukin-13 ( IL-13 ) , induce expression of a distinct subset of genes in human monocytes , including FcepsilonRIIb ( CD23 ) , 15-lipoxygenase , IL-1 receptor antagonist ( IL-1ra ) , and type I and type II IL-1 receptors ( IL-1R ) .

The <protein>Th2-type cytokines</protein> , <protein>interleukin-4</protein> ( <protein>IL-4</protein> ) and <protein>interleukin-13</protein> ( <protein>IL-13</protein> ) , induce expression of a distinct subset of genes in <cell_type>human monocytes</cell_type> , including <protein>FcepsilonRIIb</protein> ( <protein>CD23</protein> ) , <protein>15-lipoxygenase</protein> , <protein>IL-1 receptor antagonist</protein> ( <protein>IL-1ra</protein> ) , and <protein>type I and type II IL-1 receptors</protein> ( <protein>IL-1R</protein> ) .


Type I interferons ( IFN-alpha and IFN-beta ) and type II interferon ( IFN-gamma ) inhibit induction of these genes by IL-4 and IL-13 .

<protein>Type I interferons</protein> ( <protein>IFN-alpha</protein> and <protein>IFN-beta</protein> ) and <protein>type II interferon</protein> ( <protein>IFN-gamma</protein> ) inhibit induction of these genes by <protein>IL-4</protein> and <protein>IL-13</protein> .


However , the mechanism by which IFNs mediate this inhibition has not been defined .

However , the mechanism by which <protein>IFNs</protein> mediate this inhibition has not been defined .


In this overview , we discuss the role of the transcription factor , STAT6 ( signal transducer and activator of transcription-6 ) in mediating IL-4- and IL-13-induced gene expression in monocytes .

In this overview , we discuss the role of the <protein>transcription factor</protein> , <protein>STAT6</protein> ( <protein>signal transducer and activator of transcription-6</protein> ) in mediating IL-4- and IL-13-induced gene expression in <cell_type>monocytes</cell_type> .


We also discuss our recent findings that type I and type II IFNs suppress IL-4 / IL-13 -inducible gene expression by inhibiting tyrosine phosphorylation and nuclear translocation of STAT6 .

We also discuss our recent findings that <protein>type I and type II IFNs</protein> suppress <protein>IL-4</protein> / <protein>IL-13</protein> -inducible gene expression by inhibiting tyrosine phosphorylation and nuclear translocation of <protein>STAT6</protein> .


The ability of type I and type II IFNs to inhibit IL-4 / IL-13 -induced STAT6 activity is dose- and time-dependent , and is not unique to monocytes because IFNs induce the same effects in fibroblasts .

The ability of <protein>type I and type II IFNs</protein> to inhibit <protein>IL-4</protein> / <protein>IL-13</protein> -induced <protein>STAT6</protein> activity is dose- and time-dependent , and is not unique to <cell_type>monocytes</cell_type> because <protein>IFNs</protein> induce the same effects in <cell_type>fibroblasts</cell_type> .


Inhibition of STAT6 activity is not evident unless cells are preincubated with IFN for at least 1 h before IL-4 stimulation .

Inhibition of <protein>STAT6</protein> activity is not evident unless cells are preincubated with <protein>IFN</protein> for at least 1 h before <protein>IL-4</protein> stimulation .


Furthermore , inhibition can be blocked by actinomycin D , indicating a requirement for de novo transcription .


We propose a model in which stimulation of monocytes by IFN activates de novo synthesis of an inhibitory factor , possibly one or more members of the SOCS/ SSI/CIS gene family , capable of suppressing activation of STAT6 by IL-4 and IL-13 .

We propose a model in which stimulation of <cell_type>monocytes</cell_type> by <protein>IFN</protein> activates de novo synthesis of an <protein>inhibitory factor</protein> , possibly one or more members of the <protein>SOCS/ SSI/CIS gene family</protein> , capable of suppressing activation of <protein>STAT6</protein> by <protein>IL-4</protein> and <protein>IL-13</protein> .


Because STAT6 activation plays an essential role in IL-4 / IL-13 -induced gene expression , the ability of IFN-beta and IFN-gamma to inhibit STAT6 activity provides an explanation for how IFNs can suppress IL-4 / IL-13 -inducible gene expression .

Because <protein>STAT6</protein> activation plays an essential role in <protein>IL-4</protein> / <protein>IL-13</protein> -induced gene expression , the ability of <protein>IFN-beta</protein> and <protein>IFN-gamma</protein> to inhibit <protein>STAT6</protein> activity provides an explanation for how <protein>IFNs</protein> can suppress <protein>IL-4</protein> / <protein>IL-13</protein> -inducible gene expression .


HLA class I -mediated induction of cell proliferation involves cyclin E -mediated inactivation of Rb function and induction of E2F activity .

<protein>HLA class I</protein> -mediated induction of cell proliferation involves <dna>cyclin E</dna> -mediated inactivation of Rb function and induction of <protein>E2F</protein> activity .


Chronic rejection of transplanted organs is manifested as atherosclerosis of the blood vessels of the allograft .


HLA class I Ags have been implicated to play a major role in this process , since signaling via HLA class I molecules can induce the proliferation of aortic endothelial as well as smooth muscle cells .

<protein>HLA class I Ags</protein> have been implicated to play a major role in this process , since signaling via <protein>HLA class I molecules</protein> can induce the proliferation of <cell_type>aortic endothelial</cell_type> as well as <cell_type>smooth muscle cells</cell_type> .


In this study , we show that HLA class I -mediated induction of cell proliferation correlates with inactivation of the Rb protein in the T cell line Jurkat as well as human aortic endothelial cells .

In this study , we show that <protein>HLA class I</protein> -mediated induction of cell proliferation correlates with inactivation of the <protein>Rb protein</protein> in the <cell_line>T cell line Jurkat</cell_line> as well as <cell_type>human aortic endothelial cells</cell_type> .


HLA class I -mediated inactivation of Rb can be inhibited specifically by neutralizing Abs to basic fibroblast growth factor ( bFGF ) , suggesting a role for FGF receptors in the signaling process .

<protein>HLA class I</protein> -mediated inactivation of <protein>Rb</protein> can be inhibited specifically by <protein>neutralizing Abs</protein> to <protein>basic fibroblast growth factor</protein> ( <protein>bFGF</protein> ) , suggesting a role for <protein>FGF receptors</protein> in the signaling process .


Signaling through HLA class I molecules induced cyclin E -associated kinase activity within 4 h in quiescent endothelial cells , and appeared to mediate the inactivation of Rb .

Signaling through <protein>HLA class I molecules</protein> induced <dna>cyclin E</dna> -associated kinase activity within 4 h in <cell_type>quiescent endothelial cells</cell_type> , and appeared to mediate the inactivation of <protein>Rb</protein> .


A cdk2 inhibitor , Olomoucine , as well as a dominant-negative cdk2 construct prevented HLA class I -mediated inactivation of Rb ; in contrast , dominant-negative cdk4 and cdk6 constructs had no effect .

A cdk2 inhibitor , Olomoucine , as well as a <dna>dominant-negative cdk2 construct</dna> prevented <protein>HLA class I</protein> -mediated inactivation of <protein>Rb</protein> ; in contrast , <dna>dominant-negative cdk4 and cdk6 constructs</dna> had no effect .


Furthermore , there was no increase in cyclin D-associated kinase activity upon HLA class I ligation , suggesting that cyclin E-dependent kinase activity mediates Rb inactivation , leading to E2F activation and cell proliferation .

Furthermore , there was no increase in <protein>cyclin D-associated kinase</protein> activity upon <protein>HLA class I</protein> ligation , suggesting that <protein>cyclin E-dependent kinase</protein> activity mediates <protein>Rb</protein> inactivation , leading to <protein>E2F</protein> activation and cell proliferation .


Immunosuppressant PG490 ( triptolide ) inhibits T-cell interleukin-2 expression at the level of purine-box/nuclear factor of activated T-cells and NF-kappaB transcriptional activation .

Immunosuppressant PG490 ( triptolide ) inhibits <protein>T-cell interleukin-2</protein> expression at the level of <protein>purine-box/nuclear factor</protein> of <cell_type>activated T-cells</cell_type> and <protein>NF-kappaB</protein> transcriptional activation .


PG490 ( triptolide ) is a diterpene triepoxide with potent immunosuppressive and antiinflammatory properties .


PG490 inhibits interleukin ( IL ) -2 expression by normal human peripheral blood lymphocytes stimulated with phorbol 12-myristate 13-acetate ( PMA ) and antibody to CD3 ( IC50 of 10 ng/ml ) , and with PMA and ionomycin ( Iono , IC50 of 40 ng/ml ) .

PG490 inhibits <protein>interleukin ( IL ) -2</protein> expression by <cell_type>normal human peripheral blood lymphocytes</cell_type> stimulated with phorbol 12-myristate 13-acetate ( PMA ) and antibody to <protein>CD3</protein> ( IC50 of 10 ng/ml ) , and with PMA and ionomycin ( Iono , IC50 of 40 ng/ml ) .


In Jurkat T-cells , PG490 inhibits PMA/Iono-stimulated IL-2 transcription .

In <cell_line>Jurkat T-cells</cell_line> , PG490 inhibits PMA/Iono-stimulated <protein>IL-2</protein> transcription .


PG490 inhibits the induction of DNA binding activity at the purine-box/antigen receptor response element ( ARRE ) /nuclear factor of activated T-cells ( NF-AT ) target sequence but not at the NF-kappaB site .

PG490 inhibits the induction of DNA binding activity at the <dna>purine-box/antigen receptor response element ( ARRE ) /nuclear factor of activated T-cells ( NF-AT ) target sequence</dna> but not at the <dna>NF-kappaB site</dna> .


PG490 can completely inhibit transcriptional activation at the purine-box/ARRE/NF-AT and NF-kappaB target DNA sequences triggered by all stimuli examined ( PMA , PMA/Iono , tumor necrosis factor-alpha ) .

PG490 can completely inhibit transcriptional activation at the <dna>purine-box/ARRE/NF-AT and NF-kappaB target DNA sequences</dna> triggered by all stimuli examined ( PMA , PMA/Iono , <protein>tumor necrosis factor-alpha</protein> ) .


PG490 also inhibits PMA-stimulated activation of a chimeric transcription factor in which the C-terminal TA1 transactivation domain of NF-kappaB p65 is fused to the DNA binding domain of GAL4 .

PG490 also inhibits PMA-stimulated activation of a <protein>chimeric transcription factor</protein> in which the <protein>C-terminal TA1 transactivation domain</protein> of <protein>NF-kappaB p65</protein> is fused to the <protein>DNA binding domain</protein> of <protein>GAL4</protein> .


In 16HBE human bronchial epithelial cells , IL-8 expression is regulated predominantly by NF-kappaB , and PG490 but not cyclosporin A can completely inhibit expression of IL-8 .

In <cell_type>16HBE human bronchial epithelial cells</cell_type> , <protein>IL-8</protein> expression is regulated predominantly by <protein>NF-kappaB</protein> , and PG490 but not cyclosporin A can completely inhibit expression of <protein>IL-8</protein> .


The mechanism of PG490 inhibition of cytokine gene expression differs from cyclosporin A and involves nuclear inhibition of transcriptional activation of NF-kappaB and the purine-box regulator operating at the ARRE/NF-AT site at a step after specific DNA binding .

The mechanism of PG490 inhibition of <dna>cytokine gene</dna> expression differs from cyclosporin A and involves nuclear inhibition of transcriptional activation of <protein>NF-kappaB</protein> and the <dna>purine-box regulator</dna> operating at the <dna>ARRE/NF-AT site</dna> at a step after specific DNA binding .


Unexpected and coordinated expression of Spi-1 , Fli-1 , and megakaryocytic genes in four Epo-dependent cell lines established from transgenic mice displaying erythroid-specific expression of a thermosensitive SV40 T antigen .

Unexpected and coordinated expression of <protein>Spi-1</protein> , <protein>Fli-1</protein> , and <dna>megakaryocytic genes</dna> in four <cell_line>Epo-dependent cell lines</cell_line> established from transgenic mice displaying erythroid-specific expression of a <protein>thermosensitive SV40 T antigen</protein> .


Most erythroleukemic cell lines established in vitro coexpress erythrocytic and megakaryocytic markers that often are associated with expression of Spi-1 and/or Fli-1 transcription factors known as transactivators of megakaryocyte-specific promoters .

Most <cell_line>erythroleukemic cell lines</cell_line> established in vitro coexpress <protein>erythrocytic and megakaryocytic markers</protein> that often are associated with expression of <protein>Spi-1</protein> and/or <protein>Fli-1 transcription factors</protein> known as <protein>transactivators of megakaryocyte-specific promoters</protein> .


In the present study , we examined the possibility of establishing new cell lines keeping strictly erythroid-specific properties in vitro through the targeted and conditional immortalization of erythrocytic progenitors .

In the present study , we examined the possibility of establishing <cell_line>new cell lines</cell_line> keeping strictly erythroid-specific properties in vitro through the targeted and conditional immortalization of <cell_type>erythrocytic progenitors</cell_type> .


For that purpose , we established several lines of transgenic mice displaying erythroid-specific expression of a thermosensitive SV40 T antigen .

For that purpose , we established several lines of transgenic mice displaying erythroid-specific expression of a <protein>thermosensitive SV40 T antigen</protein> .


As expected , these transgenic mice developed splenomegaly due to the massive amplification of Ter 119 positive erythroid nucleated cells expressing T antigen .

As expected , these transgenic mice developed splenomegaly due to the massive amplification of <cell_line>Ter 119 positive erythroid nucleated cells</cell_line> expressing <protein>T antigen</protein> .


Despite this drastic effect in vivo , the in vitro immortalization of erythropoietin-dependent erythroid progenitors unexpectedly occurred at low frequency , and all four cell lines established expressed both erythrocytic ( globins ) and megakaryocytic markers ( glycoprotein IIb , platelet factor 4 ) as well as Spi-1 and Fli-1 transcripts at permissive temperature .

Despite this drastic effect in vivo , the in vitro immortalization of <cell_type>erythropoietin-dependent erythroid progenitors</cell_type> unexpectedly occurred at low frequency , and all four <cell_line>cell lines</cell_line> established expressed both <protein>erythrocytic ( globins ) and megakaryocytic markers</protein> ( <protein>glycoprotein IIb</protein> , <protein>platelet factor 4</protein> ) as well as <protein>Spi-1</protein> and <protein>Fli-1 transcripts</protein> at permissive temperature .


Switching the cells to the nonpermissive temperature led to a marked increase in globin gene expression and concomitant decrease in expression of Spi-1 , Fli-1 , and megakaryocytic genes in an erythropoietin -dependent manner .

Switching the cells to the nonpermissive temperature led to a marked increase in <dna>globin gene</dna> expression and concomitant decrease in expression of <protein>Spi-1</protein> , <protein>Fli-1</protein> , and <dna>megakaryocytic genes</dna> in an <protein>erythropoietin</protein> -dependent manner .


Interestingly , enhanced expression of Spi-1 and Fli-1 genes already was detected in the Ter 119 positive cell population of transgenic mice spleen in vivo .

Interestingly , enhanced expression of <dna>Spi-1 and Fli-1 genes</dna> already was detected in the <cell_line>Ter 119 positive cell population</cell_line> of transgenic mice spleen in vivo .


However , like normal Ter 119 erythroid cells , these Ter 119 positive cells from transgenic mice still expressed high levels of beta-globin and very low or undetectable glycoprotein IIb and platelet factor 4 megakaryocytic transcripts .

However , like <cell_line>normal Ter 119 erythroid cells</cell_line> , these <cell_line>Ter 119 positive cells</cell_line> from transgenic mice still expressed high levels of <protein>beta-globin</protein> and very low or undetectable <protein>glycoprotein IIb</protein> and <protein>platelet factor 4 megakaryocytic transcripts</protein> .


Taken together , these data indicate that the unexpected expression of megakaryocytic genes is a specific property of immortalized cells that can not be explained only by enhanced expression of Spi-1 and/or Fli-1 genes .

Taken together , these data indicate that the unexpected expression of <dna>megakaryocytic genes</dna> is a specific property of <cell_line>immortalized cells</cell_line> that can not be explained only by enhanced expression of <dna>Spi-1 and/or Fli-1 genes</dna> .


Fludarabine-induced immunosuppression is associated with inhibition of STAT1 signaling .

Fludarabine-induced immunosuppression is associated with inhibition of <protein>STAT1</protein> signaling .


Fludarabine is a nucleoside analog used in the treatment of hematologic malignancies that can induce severe and prolonged immunosuppression .


Although it can be incorporated into the DNA of dividing cells , fludarabine is also a potent inhibitor of cells with a low growth fraction , thus it must have other mechanisms of action .


STAT1 , which is activated in response to many lymphocyte-activating cytokines including the interferons , is essential for cell-mediated immunity , as the absence of this protein is associated with prominent defects in the ability to control viral infections .

<protein>STAT1</protein> , which is activated in response to many <protein>lymphocyte-activating cytokines</protein> including the <protein>interferons</protein> , is essential for cell-mediated immunity , as the absence of this protein is associated with prominent defects in the ability to control viral infections .


Here we show that fludarabine , but not the immunosuppressant cyclosporine A , inhibits the cytokine -induced activation of STAT1 and STAT1 -dependent gene transcription in normal resting or activated lymphocytes .

Here we show that fludarabine , but not the immunosuppressant cyclosporine A , inhibits the <protein>cytokine</protein> -induced activation of <protein>STAT1</protein> and <protein>STAT1</protein> -dependent gene transcription in <cell_type>normal resting or activated lymphocytes</cell_type> .


Fludarabine caused a specific depletion of STAT1 protein ( and mRNA ) but not of other STATs .

Fludarabine caused a specific depletion of <protein>STAT1 protein</protein> ( and mRNA ) but not of other <protein>STATs</protein> .


This loss of STAT1 was also seen in cells from patients treated with fludarabine in vivo .

This loss of <protein>STAT1</protein> was also seen in cells from patients treated with fludarabine in vivo .


Brief exposure to fludarabine led to a sustained loss of STAT1 , analogous to the prolonged period of immunosuppression induced by exposure to the drug in vivo .

Brief exposure to fludarabine led to a sustained loss of <protein>STAT1</protein> , analogous to the prolonged period of immunosuppression induced by exposure to the drug in vivo .


Thus , STAT1 may be a useful target in the development of new immunosuppressive and antineoplastic agents .

Thus , <protein>STAT1</protein> may be a useful target in the development of new immunosuppressive and antineoplastic agents .


Studies into the effect of tyrosine phosphatase inhibitor phenylarsine oxide on NFkappaB activation in T lymphocytes during aging : evidence for altered IkappaB-alpha phosphorylation and degradation .

Studies into the effect of <protein>tyrosine phosphatase</protein> inhibitor phenylarsine oxide on <protein>NFkappaB</protein> activation in <cell_type>T lymphocytes</cell_type> during aging : evidence for altered <protein>IkappaB-alpha</protein> phosphorylation and degradation .


Nuclear Factor kappa B ( NFkappaB ) is a critical regulator of several genes involved in immune and inflammatory responses .

<protein>Nuclear Factor kappa B</protein> ( <protein>NFkappaB</protein> ) is a critical regulator of several genes involved in immune and inflammatory responses .


Treatment of T cells with a variety of stimuli , including TNF-alpha , leads to the translocation of the active p65-50 heterodimer to the nucleus , albeit at a lower level in T cells from the elderly .

Treatment of <cell_type>T cells</cell_type> with a variety of stimuli , including <protein>TNF-alpha</protein> , leads to the translocation of the active <protein>p65-50 heterodimer</protein> to the nucleus , albeit at a lower level in <cell_type>T cells</cell_type> from the elderly .


We demonstrate here that pretreatment with PAO results in the inhibition of NFkappaB induction in TNF-alpha treated T cells , suggesting a role for PAO-sensitive phosphatase in the activation of the NFkappaB via this pathway in human T cells .

We demonstrate here that pretreatment with PAO results in the inhibition of <protein>NFkappaB</protein> induction in <protein>TNF-alpha</protein> treated <cell_type>T cells</cell_type> , suggesting a role for <protein>PAO-sensitive phosphatase</protein> in the activation of the <protein>NFkappaB</protein> via this pathway in <cell_type>human T cells</cell_type> .


Furthermore , it demonstrates that aging does not influence the sensitivity of this phosphatase .

Furthermore , it demonstrates that aging does not influence the sensitivity of this <protein>phosphatase</protein> .


Treatment with DMP prior to treatment with PAO and TNF abolishes the inhibition induced by PAO , in T cells from both young and old donors , alike .

Treatment with DMP prior to treatment with PAO and <protein>TNF</protein> abolishes the inhibition induced by PAO , in <cell_type>T cells</cell_type> from both young and old donors , alike .


Finally , we demonstrate that a failure to degrade IkappaB-alpha in cytosols of TNF-treated T cells pretreated with PAO is due to its interference with the phosphorylation of IkappaB-alpha and not due to its inhibitory effect on proteasomal degradation .

Finally , we demonstrate that a failure to degrade <protein>IkappaB-alpha</protein> in cytosols of <cell_type>TNF-treated T cells</cell_type> pretreated with PAO is due to its interference with the phosphorylation of <protein>IkappaB-alpha</protein> and not due to its inhibitory effect on proteasomal degradation .


These data collectively suggest that PAO interferes with the phosphorylation and the regulated degradation of IkappaB-alpha , induced by TNF , without affecting the chymotryptic activity of the proteasome , independent of age .

These data collectively suggest that PAO interferes with the phosphorylation and the regulated degradation of <protein>IkappaB-alpha</protein> , induced by <protein>TNF</protein> , without affecting the chymotryptic activity of the <protein>proteasome</protein> , independent of age .


Spi-C , a novel Ets protein that is temporally regulated during B lymphocyte development .

<protein>Spi-C</protein> , a novel <protein>Ets protein</protein> that is temporally regulated during B lymphocyte development .


A novel Ets protein was isolated by yeast one-hybrid screening of a cDNA library made from lipopolysaccharide-stimulated mouse splenic B cells , using the SP6 kappa promoter kappaY element as a bait .

A novel <protein>Ets protein</protein> was isolated by yeast one-hybrid screening of a <dna>cDNA library</dna> made from <cell_line>lipopolysaccharide-stimulated mouse splenic B cells</cell_line> , using the <dna>SP6 kappa promoter kappaY element</dna> as a bait .


The novel Ets protein was most closely related to PU.1 and Spi-B within the DNA binding Ets domain and was therefore named Spi-C .

The novel <protein>Ets protein</protein> was most closely related to <protein>PU.1</protein> and <protein>Spi-B</protein> within the <dna>DNA binding Ets domain</dna> and was therefore named <protein>Spi-C</protein> .


However , Spi-C may represent a novel subgroup within the Ets protein family , as it differed significantly from Spi-B and PU.1 within helix 1 of the Ets domain .

However , <protein>Spi-C</protein> may represent a novel subgroup within the <protein>Ets protein family</protein> , as it differed significantly from <protein>Spi-B</protein> and <protein>PU.1</protein> within <protein>helix 1</protein> of the <protein>Ets domain</protein> .


Spi-C was encoded by a single-copy gene that was mapped to chromosome 10 , region C .

<protein>Spi-C</protein> was encoded by a <dna>single-copy gene</dna> that was mapped to <dna>chromosome 10</dna> , <dna>region C</dna> .


Spi-C interacted with DNA similarly to PU.1 as judged by methylation interference , band-shift and site selection analysis , and activated transcription of a kappaY element reporter gene upon co-transfection of HeLa cells .

<protein>Spi-C</protein> interacted with DNA similarly to <protein>PU.1</protein> as judged by methylation interference , band-shift and site selection analysis , and activated transcription of a <dna>kappaY element reporter gene</dna> upon co-transfection of <cell_line>HeLa cells</cell_line> .


Spi-C RNA was expressed in mature B lymphocytes and at lower levels in macrophages .

<rna>Spi-C RNA</rna> was expressed in <cell_type>mature B lymphocytes</cell_type> and at lower levels in <cell_type>macrophages</cell_type> .


Furthermore , pre-B cell and plasma cell lines were Spi-C -negative , suggesting that Spi-C might be a regulatory molecule during a specific phase of B lymphoid development .

Furthermore , <cell_line>pre-B cell and plasma cell lines</cell_line> were <protein>Spi-C</protein> -negative , suggesting that <protein>Spi-C</protein> might be a <protein>regulatory molecule</protein> during a specific phase of B lymphoid development .


Glucocorticoid-induced cell death requires autoinduction of glucocorticoid receptor expression in human leukemic T cells .

Glucocorticoid-induced cell death requires autoinduction of <protein>glucocorticoid receptor</protein> expression in <cell_type>human leukemic T cells</cell_type> .


In contrast to the negative autoregulation of glucocorticoid receptor ( GR ) expression seen in most cells and tissues , GR expression is positively autoregulated in human leukemic T cells and in other cells sensitive to glucocorticoid-induced cell death .

In contrast to the negative autoregulation of <protein>glucocorticoid receptor</protein> ( <protein>GR</protein> ) expression seen in most cells and tissues , <protein>GR</protein> expression is positively autoregulated in <cell_type>human leukemic T cells</cell_type> and in other cells sensitive to glucocorticoid-induced cell death .


To determine whether positive autoregulation is a necessary component of glucocorticoid-induced cell death , a wild-type GR gene under the control of a tetracycline-regulated promoter was stably transfected into glucocorticoid-resistant cells lacking endogenous functional receptor .

To determine whether positive autoregulation is a necessary component of glucocorticoid-induced cell death , a <dna>wild-type GR gene</dna> under the control of a <dna>tetracycline-regulated promoter</dna> was stably transfected into <cell_line>glucocorticoid-resistant cells</cell_line> lacking endogenous functional receptor .


Transfectants grown in the presence of tetracycline contained about 15 , 000 receptors/cell , a value approximately equal to basal level GR expression in glucocorticoid-sensitive 6TG1.1 cells before steroid treatment .

<cell_line>Transfectants</cell_line> grown in the presence of tetracycline contained about 15 , 000 receptors/cell , a value approximately equal to basal level <protein>GR</protein> expression in <cell_line>glucocorticoid-sensitive 6TG1.1 cells</cell_line> before steroid treatment .


Under these conditions , dexamethasone had a minimal effect on cell growth , elicited little internucleosomal DNA fragmentation , and induced no cell cycle perturbation .


In the absence of tetracycline , GR mRNA and protein expression increased 2-3-fold , and cells expressed 48 , 000 receptors , a level nearly equivalent to that present in 6TG1.1 cells after 18 h of autoinduction .

In the absence of tetracycline , <rna>GR mRNA</rna> and protein expression increased 2-3-fold , and cells expressed 48 , 000 receptors , a level nearly equivalent to that present in <cell_line>6TG1.1 cells</cell_line> after 18 h of autoinduction .


Under these conditions , dexamethasone markedly inhibited cell growth , caused G1 arrest , and induced significant internucleosomal DNA fragmentation .


These studies therefore suggest that basal level GR expression is inadequate to mediate glucocorticoid-induced apoptosis in glucocorticoid-sensitive T cells and that positive autoregulation is a necessary component of this process .

These studies therefore suggest that basal level <protein>GR</protein> expression is inadequate to mediate glucocorticoid-induced apoptosis in <cell_line>glucocorticoid-sensitive T cells</cell_line> and that positive autoregulation is a necessary component of this process .


Constitutive activation of NF-kappaB in primary adult T-cell leukemia cells .

Constitutive activation of <protein>NF-kappaB</protein> in <cell_type>primary adult T-cell leukemia cells</cell_type> .


Human T-cell leukemia virus type I ( HTLV-I ) is an etiologic agent of adult T-cell leukemia ( ATL ) .


The viral protein Tax induces the activation and nuclear translocalization of transcription factor NF-kappaB , which is proposed to play a crucial role in the transformation of T cells by HTLV-I .

The <protein>viral protein</protein> <protein>Tax</protein> induces the activation and nuclear translocalization of <protein>transcription factor</protein> <protein>NF-kappaB</protein> , which is proposed to play a crucial role in the transformation of <cell_type>T cells</cell_type> by HTLV-I .


However , the HTLV-I genes including Tax are not expressed significantly in primary leukemic cells from ATL patients .

However , the <dna>HTLV-I genes</dna> including <protein>Tax</protein> are not expressed significantly in <cell_type>primary leukemic cells</cell_type> from ATL patients .


In this study , we examined the basis for NF-kappaB activation in freshly isolated leukemic cells from ATL patients .

In this study , we examined the basis for <protein>NF-kappaB</protein> activation in <cell_type>freshly isolated leukemic cells</cell_type> from ATL patients .


We found that leukemic cells from ATL patients , like HTLV-I-infected T-cell lines , display constitutive NF-kappaB DNA binding activity and increased degradation of IkappaBalpha ( an inhibitor of NF-kappaB ) .

We found that <cell_type>leukemic cells</cell_type> from ATL patients , like <cell_line>HTLV-I-infected T-cell lines</cell_line> , display constitutive <protein>NF-kappaB</protein> DNA binding activity and increased degradation of <protein>IkappaBalpha</protein> ( an inhibitor of <protein>NF-kappaB</protein> ) .


Whereas the NF-kappaB binding activity in Tax-expressing T-cell lines consisted mostly of p50/c-Rel , fresh ATL samples contained p50/p50 and p50/p65 heterodimers .

Whereas the <protein>NF-kappaB</protein> binding activity in <cell_line>Tax-expressing T-cell lines</cell_line> consisted mostly of <protein>p50/c-Rel</protein> , fresh ATL samples contained <protein>p50/p50 and p50/p65 heterodimers</protein> .


One T-cell line derived from ATL leukemic cells , TL-Om1 , displayed constitutive NF-kappaB activity , as well as enhanced degradation of IkappaBalpha , despite the lack of detectable Tax expression .

One <cell_line>T-cell line</cell_line> derived from ATL <cell_type>leukemic cells</cell_type> , TL-Om1 , displayed constitutive <protein>NF-kappaB</protein> activity , as well as enhanced degradation of <protein>IkappaBalpha</protein> , despite the lack of detectable <protein>Tax</protein> expression .


Interestingly , the NF-kappaB in TL-Om1 consists of p50/p50 and p50/p65 like that in fresh primary leukemic cells .

Interestingly , the <protein>NF-kappaB</protein> in TL-Om1 consists of <protein>p50/p50</protein> and <protein>p50/p65</protein> like that in fresh <cell_type>primary leukemic cells</cell_type> .


Our results suggest that activation of NF-kappaB occurs through a Tax -independent mechanism in leukemic cells of ATL patients , possibly due to differential NF-kappaB subunit activation .

Our results suggest that activation of <protein>NF-kappaB</protein> occurs through a <protein>Tax</protein> -independent mechanism in <cell_type>leukemic cells</cell_type> of ATL patients , possibly due to differential <protein>NF-kappaB</protein> subunit activation .


Interferon-alpha induction of STATs1 , -3 DNA binding and growth arrest is independent of Lck and active mitogen-activated kinase in T cells .

<protein>Interferon-alpha</protein> induction of <protein>STATs1 , -3</protein> DNA binding and growth arrest is independent of <protein>Lck</protein> and active <protein>mitogen-activated kinase</protein> in <cell_type>T cells</cell_type> .


Type I interferons ( IFNs ) are a family of cytokines that have antiviral and antiproliferative effects .

Type I <protein>interferons</protein> ( <protein>IFNs</protein> ) are a family of <protein>cytokines</protein> that have antiviral and antiproliferative effects .


Data regarding the processes by which these cytokines transduce signals from the cell membrane to the nucleus are becoming increasingly complex .

Data regarding the processes by which these <protein>cytokines</protein> transduce signals from the cell membrane to the nucleus are becoming increasingly complex .


The most characterized pathway is via JAK -STAT signaling .

The most characterized pathway is via <protein>JAK</protein> <protein>-STAT</protein> signaling .


Previous studies established a potential role for the Src-family kinase Lck in JAK -STAT signaling .

Previous studies established a potential role for the <protein>Src-family kinase</protein> <protein>Lck</protein> in <protein>JAK</protein> <protein>-STAT</protein> signaling .


Therefore , this study was designed to analyze the role of Lck in IFN-alpha signaling by using the Jurkat , JCam ( an Lck-defective cell line derived from Jurkat ) , and JCam/Lck ( JCam cells with Lck restored ) .

Therefore , this study was designed to analyze the role of <protein>Lck</protein> in <protein>IFN-alpha</protein> signaling by using the Jurkat , JCam ( an <cell_line>Lck-defective cell line</cell_line> derived from <cell_line>Jurkat</cell_line> ) , and <cell_line>JCam/Lck</cell_line> ( <cell_line>JCam cells</cell_line> with <protein>Lck</protein> restored ) .


The results show that IFN-alpha can induce MAPK activity , but only in cells containing Lck .

The results show that <protein>IFN-alpha</protein> can induce <protein>MAPK</protein> activity , but only in cells containing <protein>Lck</protein> .


Furthermore , STATs1 and -3 are effectively phosphorylated and activated to bind DNA in the absence of Lck expression in IFN-alpha-treated cells .

Furthermore , <protein>STATs1 and -3</protein> are effectively phosphorylated and activated to bind DNA in the absence of <protein>Lck</protein> expression in <cell_line>IFN-alpha-treated cells</cell_line> .


Finally , the results demonstrate that IFN-alpha exerts an antiproliferative effect in all three cell lines .

Finally , the results demonstrate that <protein>IFN-alpha</protein> exerts an antiproliferative effect in all three cell lines .


These data indicate that Lck and active MAPK do not affect IFN-alpha -induced growth arrest or induction of STAT1s1 and -3 DNA binding ability .

These data indicate that <protein>Lck</protein> and active <protein>MAPK</protein> do not affect <protein>IFN-alpha</protein> -induced growth arrest or induction of STAT1s1 and -3 DNA binding ability .


Copyright 1999 Academic Press .


Selective activation and functional significance of p38alpha mitogen-activated protein kinase in lipopolysaccharide-stimulated neutrophils .

Selective activation and functional significance of <protein>p38alpha mitogen-activated protein kinase</protein> in <cell_line>lipopolysaccharide-stimulated neutrophils</cell_line> .


Activation of leukocytes by proinflammatory stimuli selectively initiates intracellular signal transduction via sequential phosphorylation of kinases .

Activation of <cell_type>leukocytes</cell_type> by proinflammatory stimuli selectively initiates intracellular signal transduction via sequential phosphorylation of <protein>kinases</protein> .


Lipopolysaccharide ( LPS ) stimulation of human neutrophils is known to result in activation of p38 mitogen-activated protein kinase ( MAPk ) ; however , the upstream activator ( s ) of p38 MAPk is unknown , and consequences of p38 MAPk activation remain largely undefined .

Lipopolysaccharide ( LPS ) stimulation of <cell_type>human neutrophils</cell_type> is known to result in activation of <protein>p38 mitogen-activated protein kinase</protein> ( <protein>MAPk</protein> ) ; however , the <protein>upstream activator</protein> ( s ) of <protein>p38 MAPk</protein> is unknown , and consequences of <protein>p38 MAPk</protein> activation remain largely undefined .


We investigated the MAPk kinase ( MKK ) that activates p38 MAPk in response to LPS , the p38 MAPk isoforms that are activated as part of this pathway , and the functional responses affected by p38 MAPk activation .

We investigated the <protein>MAPk kinase</protein> ( <protein>MKK</protein> ) that activates <protein>p38 MAPk</protein> in response to LPS , the <protein>p38 MAPk isoforms</protein> that are activated as part of this pathway , and the functional responses affected by <protein>p38 MAPk</protein> activation .


Although MKK3 , MKK4 , and MKK6 all activated p38 MAPk in experimental models , only MKK3 was found to activate recombinant p38 MAPk in LPS-treated neutrophils .

Although <protein>MKK3</protein> , <protein>MKK4</protein> , and <protein>MKK6</protein> all activated <protein>p38 MAPk</protein> in experimental models , only <protein>MKK3</protein> was found to activate recombinant <protein>p38 MAPk</protein> in LPS-treated neutrophils .


Of p38 MAPk isoforms studied , only p38alpha and p38delta were detected in neutrophils .

Of <protein>p38 MAPk isoforms</protein> studied , only <protein>p38alpha</protein> and <protein>p38delta</protein> were detected in <cell_type>neutrophils</cell_type> .


LPS stimulation selectively activated p38alpha .

LPS stimulation selectively activated <protein>p38alpha</protein> .


Specific inhibitors of p38alpha MAPk blocked LPS-induced adhesion , nuclear factor-kappa B ( NF-kappaB ) activation , and synthesis of tumor necrosis factor-alpha ( TNF-alpha ) .

Specific inhibitors of <protein>p38alpha MAPk</protein> blocked LPS-induced adhesion , nuclear factor-kappa B ( <protein>NF-kappaB</protein> ) activation , and synthesis of <protein>tumor necrosis factor-alpha</protein> ( <protein>TNF-alpha</protein> ) .


Inhibition of p38alpha MAPk resulted in a transient decrease in TNF-alpha mRNA accumulation but persistent loss of TNF-alpha synthesis .

Inhibition of <protein>p38alpha MAPk</protein> resulted in a transient decrease in <rna>TNF-alpha mRNA</rna> accumulation but persistent loss of <protein>TNF-alpha</protein> synthesis .


These findings support a pathway by which LPS stimulation of neutrophils results in activation of MKK3 , which in turn activates p38alpha MAPk , ultimately regulating adhesion , NF-kappaB activation , enhanced gene expression of TNF-alpha , and regulation of TNF-alpha synthesis .

These findings support a pathway by which LPS stimulation of <cell_type>neutrophils</cell_type> results in activation of <protein>MKK3</protein> , which in turn activates <protein>p38alpha MAPk</protein> , ultimately regulating adhesion , <protein>NF-kappaB</protein> activation , enhanced gene expression of <protein>TNF-alpha</protein> , and regulation of <protein>TNF-alpha</protein> synthesis .


The evolutionarily conserved sequence upstream of the human Ig heavy chain S gamma 3 region is an inducible promoter : synergistic activation by CD40 ligand and IL-4 via cooperative NF-kappa B and STAT-6 binding sites .

The <dna>evolutionarily conserved sequence</dna> upstream of the <protein>human Ig heavy chain S gamma 3 region</protein> is an <dna>inducible promoter</dna> : synergistic activation by <protein>CD40 ligand</protein> and <protein>IL-4</protein> via cooperative <dna>NF-kappa B and STAT-6 binding sites</dna> .


Germline C gamma gene transcription is a crucial event in the process that leads to switch DNA recombination to IgG , but its regulation in the human is poorly understood .

Germline C gamma gene transcription is a crucial event in the process that leads to switch DNA recombination to <protein>IgG</protein> , but its regulation in the human is poorly understood .


We took advantage of our monoclonal model of germinal center B cell differentiation , IgM+ IgD+ CL-01 cells , to define the role of the I gamma 3 evolutionarily conserved sequence ( ECS ) in the germline transcriptional activation of the human C gamma 3 gene .

We took advantage of our monoclonal model of <cell_type>germinal center B cell</cell_type> differentiation , <cell_line>IgM+ IgD+ CL-01 cells</cell_line> , to define the role of the <protein>I gamma 3</protein> <dna>evolutionarily conserved sequence</dna> ( <dna>ECS</dna> ) in the <dna>germline</dna> transcriptional activation of the <dna>human C gamma 3 gene</dna> .


The I gamma 3 ECS lies upstream of the major I gamma 3 transcription initiation site and displays more than 90 % identity with the corresponding human I gamma 1 , I gamma 2 , and I gamma 4 regions .

The <protein>I gamma 3</protein> <dna>ECS</dna> lies upstream of the <dna>major I gamma 3 transcription initiation site</dna> and displays more than 90 % identity with the corresponding <dna>human I gamma 1</dna> , <dna>I gamma 2</dna> , and <dna>I gamma 4</dna> regions .


Reporter luciferase gene vectors containing the human gamma 3 ECS were used to transfect CL-01 cells , which have been shown to undergo Smu -- > S gamma 3 DNA recombination , upon engagement of CD40 by CD40 ligand ( CD40L ) and exposure to IL-4 .

<dna>Reporter luciferase gene vectors</dna> containing the <dna>human gamma 3 ECS</dna> were used to transfect <cell_line>CL-01 cells</cell_line> , which have been shown to undergo Smu -- > S gamma 3 DNA recombination , upon engagement of <protein>CD40</protein> by <protein>CD40 ligand</protein> ( <protein>CD40L</protein> ) and exposure to <protein>IL-4</protein> .


In these transfected CL-01 cells , CD40 : CD40L engagement and exposure to IL-4 synergistically induced gamma 3 ECS-dependent luciferase reporter gene activation .

In these transfected <cell_line>CL-01 cells</cell_line> , CD40 : <protein>CD40L</protein> engagement and exposure to <protein>IL-4</protein> synergistically induced gamma 3 ECS-dependent <dna>luciferase reporter gene</dna> activation .


Targeted mutational analysis demonstrated that a tandem NF-kappa B/Rel binding motif is critical for the gamma 3 ECS responsiveness to both CD40L and IL-4 , while a STAT-6-binding site is additionally required for IL-4 inducibility .

Targeted mutational analysis demonstrated that a tandem <dna>NF-kappa B/Rel binding motif</dna> is critical for the <dna>gamma 3 ECS</dna> responsiveness to both <protein>CD40L</protein> and <protein>IL-4</protein> , while a <dna>STAT-6-binding site</dna> is additionally required for <protein>IL-4</protein> inducibility .


Electrophoretic mobility shift assays showed that p50/p65/c-Rel and STAT-6 are effectively induced by CD40L and IL-4 , respectively , and bind to specific DNA motifs within the ECS .

Electrophoretic mobility shift assays showed that <protein>p50/p65/c-Rel</protein> and <protein>STAT-6</protein> are effectively induced by <protein>CD40L</protein> and <protein>IL-4</protein> , respectively , and bind to specific <dna>DNA motifs</dna> within the <dna>ECS</dna> .


These partially overlapping CD40L and IL-4 responsive elements are functionally cooperative as the disruption of one of them prevents synergistic promoter activation .

These partially overlapping <dna>CD40L and IL-4 responsive elements</dna> are functionally cooperative as the disruption of one of them prevents synergistic promoter activation .


Thus , the gamma 3 ECS is an inducible promoter containing cis elements that critically mediate CD40L and IL-4 -triggered transcriptional activation of the human C gamma 3 gene .

Thus , the <dna>gamma 3 ECS</dna> is an inducible promoter containing <dna>cis elements</dna> that critically mediate <protein>CD40L</protein> and <protein>IL-4</protein> -triggered transcriptional activation of the <dna>human C gamma 3 gene</dna> .


CIITA -induced occupation of MHC class II promoters is independent of the cooperative stabilization of the promoter-bound multi-protein complexes .

<protein>CIITA</protein> -induced occupation of <dna>MHC class II promoters</dna> is independent of the cooperative stabilization of the <protein>promoter-bound multi-protein complexes</protein> .


Precise regulation of MHC class II expression plays a crucial role in the control of the immune response .

Precise regulation of <cell_type>MHC class II</cell_type> expression plays a crucial role in the control of the immune response .


The transactivator CIITA behaves as a master controller of constitutive and inducible MHC class II gene activation , but its exact mechanism of action is not known .

The <protein>transactivator</protein> <protein>CIITA</protein> behaves as a master controller of constitutive and inducible <dna>MHC class II gene</dna> activation , but its exact mechanism of action is not known .


Activation of MHC class II promoters requires binding of at least three distinct multi-protein complexes ( RFX , X2BP and NF-Y ) .

Activation of <dna>MHC class II promoters</dna> requires binding of at least three distinct <protein>multi-protein complexes</protein> ( <protein>RFX</protein> , <protein>X2BP</protein> and <protein>NF-Y</protein> ) .


It is known that the stability of this binding results from cooperative interactions between these proteins .


We show here that expression of CIITA in MHC class II -cells triggers occupation of the promoters by these complexes .

We show here that expression of <protein>CIITA</protein> in <cell_line>MHC class II -cells</cell_line> triggers occupation of the promoters by these complexes .


This observation raised the possibility that the effect of CIITA on promoter occupation is mediated by an effect on the cooperative stabilization of the DNA-bound multi-protein complexes .

This observation raised the possibility that the effect of <protein>CIITA</protein> on promoter occupation is mediated by an effect on the cooperative stabilization of the <protein>DNA-bound multi-protein complexes</protein> .


We show , however , that the presence of CIITA does not affect the stability of the higher-order protein complex formed on DNA by RFX , X2BP and NF-Y .

We show , however , that the presence of <protein>CIITA</protein> does not affect the stability of the higher-order protein complex formed on DNA by <protein>RFX</protein> , <protein>X2BP</protein> and <protein>NF-Y</protein> .


This suggests other mechanisms for CIITA -induced promoter occupancy , such as an effect on chromatin structure leading to increased accessibility of MHC class II promoters .

This suggests other mechanisms for <protein>CIITA</protein> -induced promoter occupancy , such as an effect on <dna>chromatin</dna> structure leading to increased accessibility of <dna>MHC class II promoters</dna> .


This ability of CIITA to facilitate promoter occupation is undissociable from its transactivation potential .

This ability of <protein>CIITA</protein> to facilitate promoter occupation is undissociable from its transactivation potential .


Finally , we conclude that this effect of CIITA is cell-type specific , since expression of CIITA is not required for normal occupation of MHC class II promoters in B lymphocytes .

Finally , we conclude that this effect of <protein>CIITA</protein> is cell-type specific , since expression of <protein>CIITA</protein> is not required for normal occupation of <dna>MHC class II promoters</dna> in <cell_type>B lymphocytes</cell_type> .


GrpL , a Grb2 -related adaptor protein , interacts with SLP-76 to regulate nuclear factor of activated T cell activation .

<protein>GrpL</protein> , a <protein>Grb2</protein> -related <protein>adaptor protein</protein> , interacts with <protein>SLP-76</protein> to regulate <protein>nuclear factor of activated T cell</protein> activation .


Propagation of signals from the T cell antigen receptor ( TCR ) involves a number of adaptor molecules .

Propagation of signals from the <protein>T cell antigen receptor</protein> ( <protein>TCR</protein> ) involves a number of adaptor molecules .


SH2 domain-containing protein 76 ( SLP-76 ) interacts with the guanine nucleotide exchange factor Vav to activate the nuclear factor of activated cells ( NF-AT ) , and its expression is required for normal T cell development .

<protein>SH2 domain-containing protein 76</protein> ( <protein>SLP-76</protein> ) interacts with the <protein>guanine nucleotide exchange factor</protein> <protein>Vav</protein> to activate the <protein>nuclear factor of activated cells</protein> ( <protein>NF-AT</protein> ) , and its expression is required for normal <cell_type>T cell</cell_type> development .


We report the cloning and characterization of a novel Grb2-like adaptor molecule designated as Grb2-related protein of the lymphoid system ( GrpL ) .

We report the cloning and characterization of a novel <protein>Grb2-like adaptor molecule</protein> designated as <protein>Grb2-related protein of the lymphoid system</protein> ( <protein>GrpL</protein> ) .


Expression of GrpL is restricted to hematopoietic tissues , and it is distinguished from Grb2 by having a proline-rich region .

Expression of <protein>GrpL</protein> is restricted to hematopoietic tissues , and it is distinguished from <protein>Grb2</protein> by having a <protein>proline-rich region</protein> .


GrpL can be coimmunoprecipitated with SLP-76 but not with Sos1 or Sos2 from Jurkat cell lysates .

<protein>GrpL</protein> can be coimmunoprecipitated with <protein>SLP-76</protein> but not with <protein>Sos1</protein> or <protein>Sos2</protein> from <cell_line>Jurkat cell</cell_line> lysates .


In contrast , Grb2 can be coimmunoprecipitated with Sos1 and Sos2 but not with SLP-76 .

In contrast , <protein>Grb2</protein> can be coimmunoprecipitated with <protein>Sos1</protein> and <protein>Sos2</protein> but not with <protein>SLP-76</protein> .


Moreover , tyrosine-phosphorylated LAT/pp36/38 in detergent lysates prepared from anti-CD3 stimulated T cells associated with Grb2 but not GrpL .

Moreover , <protein>tyrosine-phosphorylated LAT/pp36/38</protein> in detergent lysates prepared from <cell_type>anti-CD3 stimulated T cells</cell_type> associated with <protein>Grb2</protein> but not <protein>GrpL</protein> .


These data reveal the presence of distinct complexes involving GrpL and Grb2 in T cells .

These data reveal the presence of distinct complexes involving <protein>GrpL</protein> and <protein>Grb2</protein> in <cell_type>T cells</cell_type> .


A functional role of the GrpL-SLP-76 complex is suggested by the ability of GrpL to act alone or in concert with SLP-76 to augment NF-AT activation in Jurkat T cells .

A functional role of the <protein>GrpL-SLP-76 complex</protein> is suggested by the ability of <protein>GrpL</protein> to act alone or in concert with <protein>SLP-76</protein> to augment <protein>NF-AT</protein> activation in <cell_line>Jurkat</cell_line> <cell_type>T cells</cell_type> .


Differential induction of interferon ( IFN ) -inducible protein 10 following differentiation of a monocyte , macrophage cell lineage is related to the changes of nuclear proteins bound to IFN stimulus response element and kappaB sites .

Differential induction of <protein>interferon ( IFN ) -inducible protein 10</protein> following differentiation of a <cell_type>monocyte</cell_type> , <cell_type>macrophage cell</cell_type> lineage is related to the changes of <protein>nuclear proteins</protein> bound to <dna>IFN stimulus response element</dna> and <dna>kappaB sites</dna> .


We examined chemokine gene expression following the differentiation of a monocyte , macrophage cell lineage .

We examined <protein>chemokine</protein> gene expression following the differentiation of a <cell_type>monocyte</cell_type> , <cell_line>macrophage cell lineage</cell_line> .


The human monoblastic cell line , U937 was differentiated to macrophages by the treatment with either phorbol 12-myristate 13-acetate ( PMA ) , retinoic acid ( RA ) , or vitamin D3 ( VitD3 ) .

The <cell_line>human monoblastic cell line</cell_line> , <cell_line>U937</cell_line> was differentiated to <cell_type>macrophages</cell_type> by the treatment with either phorbol 12-myristate 13-acetate ( PMA ) , retinoic acid ( RA ) , or vitamin D3 ( VitD3 ) .


The gene expression of interferon ( IFN ) -inducible protein 10 ( IP-10 ) ( a CXC chemokine ) was markedly augmented by the IFNgamma treatment in PMA -or RA-differentiated U937 cells , but only marginally in undifferentiated or VitD3-treated cells .

The gene expression of <protein>interferon ( IFN ) -inducible protein 10</protein> ( <protein>IP-10</protein> ) ( a <protein>CXC chemokine</protein> ) was markedly augmented by the <protein>IFNgamma</protein> treatment in PMA -or RA-differentiated <cell_line>U937 cells</cell_line> , but only marginally in undifferentiated or <cell_line>VitD3-treated cells</cell_line> .


In contrast , another inducible gene expression of monocyte chemotactic protein-1 ( a CC chemokine ) and the activation of the transcriptional factor ( FcRFgamma ) bound to the gamma response region were similarly or less abundantly induced by IFNgamma treatment in PMA -or RA-differentiated U937 cells , indicating that increased IP-10 mRNA induction was not due to the augmented ability of the cells to respond to the presence of IFNgamma .

In contrast , another inducible gene expression of <protein>monocyte chemotactic protein-1</protein> ( a <protein>CC chemokine</protein> ) and the activation of the <protein>transcriptional factor</protein> ( <protein>FcRFgamma</protein> ) bound to the <dna>gamma response region</dna> were similarly or less abundantly induced by <protein>IFNgamma</protein> treatment in PMA -or RA-differentiated <cell_line>U937 cells</cell_line> , indicating that increased <rna>IP-10 mRNA</rna> induction was not due to the augmented ability of the cells to respond to the presence of <protein>IFNgamma</protein> .


Increased expression of IFNgamma -induced IP-10 mRNA following the differentiation of U937 cells was mediated largely by augmented transcriptional activity of the gene and was related to differentiation-dependent changes of the proteins bound to IFN stimulus response element ( ISRE ) and kB sites , suggesting that these nuclear proteins may determine the IP-10 mRNA inducibility by IFNgamma .

Increased expression of <protein>IFNgamma</protein> -induced <rna>IP-10 mRNA</rna> following the differentiation of <cell_line>U937 cells</cell_line> was mediated largely by augmented transcriptional activity of the gene and was related to differentiation-dependent changes of the proteins bound to <dna>IFN stimulus response element ( ISRE )</dna> and <dna>kB sites</dna> , suggesting that these <protein>nuclear proteins</protein> may determine the <rna>IP-10 mRNA</rna> inducibility by <protein>IFNgamma</protein> .


Role of cellular tumor necrosis factor receptor-associated factors in NF-kappaB activation and lymphocyte transformation by herpesvirus Saimiri STP .

Role of <protein>cellular tumor necrosis factor receptor-associated factors</protein> in <protein>NF-kappaB</protein> activation and <cell_type>lymphocyte</cell_type> transformation by herpesvirus Saimiri <protein>STP</protein> .


The STP oncoproteins of the herpesvirus saimiri ( HVS ) subgroup A strain 11 and subgroup C strain 488 are now found to be stably associated with tumor necrosis factor receptor-associated factor ( TRAF ) 1 , 2 , or 3 .

The <protein>STP oncoproteins</protein> of the herpesvirus saimiri ( HVS ) subgroup A strain 11 and subgroup C strain 488 are now found to be stably associated with <protein>tumor necrosis factor receptor-associated factor ( TRAF ) 1 , 2 , or 3</protein> .


Mutational analyses identified residues of PXQXT/S in STP-A11 as critical for TRAF association .

Mutational analyses identified residues of <protein>PXQXT/S</protein> in <protein>STP-A11</protein> as critical for <protein>TRAF</protein> association .


In addition , a somewhat divergent region of STP-C488 is critical for TRAF association .

In addition , a somewhat divergent region of <protein>STP-C488</protein> is critical for <protein>TRAF</protein> association .


Mutational analysis also revealed that STP-C488 induced NF-kappaB activation that was correlated with its ability to associate with TRAFs .

Mutational analysis also revealed that <protein>STP-C488</protein> induced <protein>NF-kappaB</protein> activation that was correlated with its ability to associate with <protein>TRAFs</protein> .


The HVS STP-C488 P10 -- > R mutant was deficient in human T-lymphocyte transformation to interleukin-2-independent growth but showed wild-type phenotype for marmoset T-lymphocyte transformation in vitro and in vivo .

The HVS <protein>STP-C488</protein> P10 -- > R mutant was deficient in human T-lymphocyte transformation to interleukin-2-independent growth but showed wild-type phenotype for marmoset T-lymphocyte transformation in vitro and in vivo .


The STP-C488 P10 -- > R mutant was also defective in Rat-1 fibroblast transformation , and fibroblast cell transformation was blocked by a TRAF2 dominant-negative mutant .

The <protein>STP-C488 P10 -- > R mutant</protein> was also defective in Rat-1 fibroblast transformation , and fibroblast cell transformation was blocked by a <protein>TRAF2</protein> dominant-negative mutant .


These data implicate TRAFs in STP-C488 -mediated transformation of human lymphocytes and rodent fibroblasts .

These data implicate <protein>TRAFs</protein> in <protein>STP-C488</protein> -mediated transformation of <cell_type>human lymphocytes</cell_type> and rodent <cell_type>fibroblasts</cell_type> .


Other factors are implicated in immortalization of common marmoset T lymphocytes and may also be critical in the transformation of human lymphocytes and rodent fibroblasts .

Other factors are implicated in immortalization of <cell_type>common marmoset T lymphocytes</cell_type> and may also be critical in the transformation of <cell_type>human lymphocytes</cell_type> and <cell_type>rodent fibroblasts</cell_type> .


Cleavage of transcription factor SP1 by caspases during anti-IgM-induced B-cell apoptosis .

Cleavage of <protein>transcription factor</protein> <protein>SP1</protein> by <protein>caspases</protein> during anti-IgM-induced <cell_type>B-cell</cell_type> apoptosis .


Apoptosis is instrumental in the processes generating the diversity of the B-cell repertoire .


Autoreactive B-cells are eliminated by anti-IgM crosslinking after encountering self-antigens , but precise mechanisms leading to B-cell apoptosis are still not well understood .

<cell_type>Autoreactive B-cells</cell_type> are eliminated by <protein>anti-IgM</protein> crosslinking after encountering <protein>self-antigens</protein> , but precise mechanisms leading to <cell_type>B-cell</cell_type> apoptosis are still not well understood .


We report here the cleavage of the transcription factor SP1 in the human Burkitt lymphoma cell line BL60 during anti-IgM -induced apoptosis .

We report here the cleavage of the <protein>transcription factor</protein> <protein>SP1</protein> in the <cell_line>human Burkitt lymphoma cell line BL60</cell_line> during <protein>anti-IgM</protein> -induced apoptosis .


Western blot analysis revealed two cleavage products of approximately 68 kDa and 45 kDa after induction of apoptosis .

Western blot analysis revealed two cleavage products of approximately <protein>68 kDa</protein> and <protein>45 kDa</protein> after induction of apoptosis .


Cleavage could be completely inhibited by zDEVD-fmk , an inhibitor specific for caspase 3-like proteases .

Cleavage could be completely inhibited by zDEVD-fmk , an inhibitor specific for <protein>caspase 3-like proteases</protein> .


In-vitro cleavage of recombinant SP1 by recombinant caspase 3 ( CPP32 ) or caspase 7 ( Mch 3 ) results in similar cleavage products as those observed in vivo .

In-vitro cleavage of <protein>recombinant SP1</protein> by <protein>recombinant caspase 3</protein> ( <protein>CPP32</protein> ) or <protein>caspase 7</protein> ( <protein>Mch 3</protein> ) results in similar cleavage products as those observed in vivo .


Recombinant caspase 6 ( Mch 2 ) primarily generates a 68-kDa cleavage product , as observed after calcium ionophore ( CaI ) induced B-cell apoptosis .

<protein>Recombinant caspase 6</protein> ( <protein>Mch 2</protein> ) primarily generates a 68-kDa cleavage product , as observed after calcium ionophore ( CaI ) induced <cell_type>B-cell</cell_type> apoptosis .


In contrast , caspase 1 ( ICE ) did not cleave SP1 in vitro .

In contrast , caspase 1 ( ICE ) did not cleave <protein>SP1</protein> in vitro .


The time course of SP1 cleavage during anti-IgM-induced apoptosis is paralleled by an increase of caspase activity measured by DEVD-p-nitroanilide ( DEVD-pNA ) cleavage .

The time course of <protein>SP1</protein> cleavage during anti-IgM-induced apoptosis is paralleled by an increase of caspase activity measured by DEVD-p-nitroanilide ( DEVD-pNA ) cleavage .


DNA band-shift assays revealed a decrease in the intensity of the full length SP1 /DNA complex and an increase in the intensity of a smaller complex due to the binding of one SP1 cleavage product .

DNA band-shift assays revealed a decrease in the intensity of the full length <protein>SP1</protein> /DNA complex and an increase in the intensity of a smaller complex due to the binding of one <protein>SP1</protein> cleavage product .


By Edman sequencing we could identify a caspase 3 cleavage site after Asp584 ( D584AQPQAGR ) , generating a 22-kDa C-terminal SP1 protein fragment which still contains the DNA binding site .

By Edman sequencing we could identify a caspase 3 cleavage site after Asp584 ( D584AQPQAGR ) , generating a 22-kDa C-terminal <protein>SP1</protein> protein fragment which still contains the DNA binding site .


Our results show the cleavage of the human transcription factor SP1 in vivo and in vitro , underlining the central role of caspase 3-like proteases during the process of anti-IgM-induced apoptosis .

Our results show the cleavage of the human <protein>transcription factor</protein> <protein>SP1</protein> in vivo and in vitro , underlining the central role of <protein>caspase 3-like proteases</protein> during the process of anti-IgM-induced apoptosis .


Stimulation of CD40 on immunogenic human malignant melanomas augments their cytotoxic T lymphocyte -mediated lysis and induces apoptosis .

Stimulation of <protein>CD40</protein> on immunogenic human malignant melanomas augments their <cell_type>cytotoxic T lymphocyte</cell_type> -mediated lysis and induces apoptosis .


Here , we report the functional expression of CD40 on human malignant melanomas ( MMs ) .

Here , we report the functional expression of <protein>CD40</protein> on human malignant melanomas ( MMs ) .


Comparison of tumor specimen from MM precursor lesions , primary tumors , and metastases revealed that CD40 surface expression is down-regulated during tumor progression .

Comparison of tumor specimen from MM precursor lesions , primary tumors , and metastases revealed that <protein>CD40</protein> surface expression is down-regulated during tumor progression .


CD40 expression was confirmed in 7 human MM cell lines established from immunogenic primary tumors or metastases , whereas 11 cell lines established from advanced stages were CD40 negative .

<protein>CD40</protein> expression was confirmed in 7 <cell_line>human MM cell lines</cell_line> established from immunogenic primary tumors or metastases , whereas 11 <cell_line>cell lines</cell_line> established from advanced stages were <protein>CD40</protein> negative .


CD40 expression could be enhanced in CD40 -positive MM by stimulation with IFN-gamma and tumor necrosis factor-alpha but not by interleukin ( IL ) -1beta or CD40 triggering .

<protein>CD40</protein> expression could be enhanced in <protein>CD40</protein> -positive MM by stimulation with <protein>IFN-gamma</protein> and <protein>tumor necrosis factor-alpha</protein> but not by <protein>interleukin ( IL ) -1beta</protein> or <protein>CD40</protein> triggering .


CD40 ligation on MM by CD40L-transfected murine L-cells or by a soluble CD40L fusion protein up-regulated their expression of intercellular adhesion molecule-1 and MHC class I and class II molecules and their secretion of IL-6 , IL-8 , tumor necrosis factor-a , and granulocyte macrophage colony-stimulating factor and also induced a rapid activation of the transcription factor nuclear factor kappaB .

<protein>CD40</protein> ligation on MM by <cell_line>CD40L-transfected murine L-cells</cell_line> or by a soluble <protein>CD40L fusion protein</protein> up-regulated their expression of <protein>intercellular adhesion molecule-1</protein> and <protein>MHC class I and class II molecules</protein> and their secretion of <protein>IL-6</protein> , <protein>IL-8</protein> , <protein>tumor necrosis factor-a</protein> , and <protein>granulocyte macrophage colony-stimulating factor</protein> and also induced a rapid activation of the <protein>transcription factor</protein> <protein>nuclear factor kappaB</protein> .


Furthermore , CD40 ligation of a HLA-A2+ , MelanA/MART1+ MM cell line enhanced its susceptibility to specific lysis by a HLA-A2-restricted , MelanA/MART-1-specific CTL clone .

Furthermore , <protein>CD40</protein> ligation of a <cell_line>HLA-A2+ , MelanA/MART1+ MM cell line</cell_line> enhanced its susceptibility to specific lysis by a <cell_line>HLA-A2-restricted , MelanA/MART-1-specific CTL clone</cell_line> .


Finally , CD40 ligation induced growth inhibition and apoptosis in MM .

Finally , <protein>CD40</protein> ligation induced growth inhibition and apoptosis in MM .


These results indicate that CD40 -CD40L interactions may play an important role in augmenting antitumor immunity and inducing apoptosis in some CD40 -positive immunogenic human MMs .

These results indicate that <protein>CD40</protein> <protein>-CD40L</protein> interactions may play an important role in augmenting antitumor immunity and inducing apoptosis in some <protein>CD40</protein> -positive immunogenic human MMs .


Human immunodeficiency virus-associated Hodgkin 's disease derives from post-germinal center B cells .

Human immunodeficiency virus-associated Hodgkin 's disease derives from <cell_type>post-germinal center B cells</cell_type> .


Human immunodeficiency virus-associated Hodgkin 's disease ( HIV-HD ) displays several peculiarities when compared with HD of the general population .


These include overrepresentation of clinically aggressive histologic types and frequent infection of Reed-Sternberg ( RS ) cells by Epstein-Barr virus ( EBV ) .

These include overrepresentation of clinically aggressive histologic types and frequent infection of <cell_line>Reed-Sternberg ( RS ) cells</cell_line> by Epstein-Barr virus ( EBV ) .


Recently , we have reported that the histogenesis of HD of the general population may be assessed by monitoring the expression pattern of BCL-6 , a transcription factor expressed in germinal center ( GC ) B cells , and of CD138/syndecan-1 ( syn-1 ) , a proteoglycan associated with post-GC , terminal B-cell differentiation .

Recently , we have reported that the histogenesis of HD of the general population may be assessed by monitoring the expression pattern of <protein>BCL-6</protein> , a <protein>transcription factor</protein> expressed in <cell_line>germinal center ( GC ) B cells</cell_line> , and of <protein>CD138/syndecan-1</protein> ( <protein>syn-1</protein> ) , a proteoglycan associated with post-GC , terminal <cell_type>B-cell</cell_type> differentiation .


In this study , we have applied these two markers to the study of HIV-HD histogenesis and correlated their expression status to the virologic features of this disease .


We have found that RS cells of all histologic categories of HIV-HD consistently display the BCL-6 ( - ) /syn-1 ( + ) phenotype and thus reflect post-GC B cells .

We have found that <cell_line>RS cells</cell_line> of all histologic categories of HIV-HD consistently display the <protein>BCL-6</protein> ( - ) /syn-1 ( + ) phenotype and thus reflect <cell_line>post-GC B cells</cell_line> .


Although BCL-6 ( - ) /syn-1 ( + ) RS cells of HIV-HD express CD40 , they are not surrounded by CD40 ligand-positive ( CD40L+ ) reactive T lymphocytes , which , in HD of the general population , are thought to regulate the disease phenotype through CD40 /CD40L interactions .

Although <protein>BCL-6</protein> ( - ) /syn-1 ( + ) <cell_line>RS cells</cell_line> of HIV-HD express <protein>CD40</protein> , they are not surrounded by <cell_type>CD40 ligand-positive ( CD40L+ ) reactive T lymphocytes</cell_type> , which , in HD of the general population , are thought to regulate the disease phenotype through <protein>CD40</protein> <protein>/CD40L</protein> interactions .