Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Pivot Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Target Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Query: EC:2.7.10.2 (
focal adhesion kinase
)
44,029
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
Experimental allergic encephalomyelitis (EAE) is a Th1 cell-mediated inflammatory demyelinating autoimmune disease model of multiple sclerosis (MS). Quercetin (3,3'4',5,7-pentahydroxy flavone) is a flavonoid phytoestrogen that has profound anticancer and anti-inflammatory activities. In this study, we show that in vivo treatment of SJL/J mice with quercetin (i.p. 50 or 100 microg every other day) ameliorates EAE in association with the inhibition of IL-12 production and neural antigen-specific Th1 differentiation. In vitro treatment of activated T cells with quercetin blocks IL-12-induced tyrosine phosphorylation of
JAK2
,
TYK2
, STAT3, and
STAT4
, resulting in a decrease in IL-12-induced T cell proliferation and Th1 differentiation. These findings highlight the fact that quercetin ameliorates EAE by blocking IL-12 signaling and Th1 differentiation and suggest its use in the treatment of MS and other Th1 cell-mediated autoimmune diseases.
...
PMID:Quercetin, a flavonoid phytoestrogen, ameliorates experimental allergic encephalomyelitis by blocking IL-12 signaling through JAK-STAT pathway in T lymphocyte. 1535 13
STAT4
is a critical mediator of IL-12-stimulated gene regulation in T-helper type 1 (Th1) cell. IL-12 activates the Janus family tyrosine kinases
JAK2
and Tyk2, which in turn phosphorylate
STAT4
on tyrosine 693. The p38 mitogen-activated protein kinase (MAPK) signaling pathway is also activated in response to IL-12, followed by phosphorylation of
STAT4
on serine 721, which is required for
STAT4
full transcriptional activity. In the present study, we demonstrated constitutive activation of
STAT4
in HTLV-I-transformed T-cell lines MT-2, MT-4 and HUT102 by immunoprecipitation, Western blotting and electrophoretic mobility shift assay (EMSA). In HTLV-I-transformed T-cell lines,
STAT4
was constitutively phosphorylated not only on tyrosine 693 but also on serine 721, and formed a heterodimer with STAT3. Constitutive phosphorylation of its upstream activators,
JAK2
, Tyk2 and p38 MAPK was also observed in the cells. EMSA and transient transfection studies further showed that the high-affinity sis-inducible element (hSIE) preferentially binds the STAT3/
STAT4
heterodimer and is constitutively transactivated in MT-2 cells in the absence of exogenous cytokine stimulation. When
STAT4
expression vector was cotransfected along with STAT3 expression vector into MT-2 cells,
STAT4
significantly synergized with STAT3 to transactivate hSIE, showing the functional importance of heterodimer formation between
STAT4
and STAT3.
...
PMID:Constitutive tyrosine and serine phosphorylation of STAT4 in T-cells transformed with HTLV-I. 1632 52
The Th1/Th2 balance determines the nature of an immune response, and particular cytokines, IL-4 and IL-12, determine the direction at the initial stage of activation through TCRs. To investigate how cytokine networks and related signaling pathways impact upon the Th1/Th2 balance, we have developed a computer model for the simulation of Th differentiation. The model includes the IL-4, IL-12 and IFN-gamma signal transduction pathways, a positive and negative feedback mechanism for cytokine signaling and cytokine-induced negative regulators such as suppressors of cytokine signaling (SOCS)1, SOCS3 and SOCS5. In the present study, we propose a 'Th0 model', in which naive T cells differentiate neither into Th1 nor into Th2 states in unskewed cytokine conditions. The model was found to be consistent with experimental results in BALB/c mice. The results of in silico analysis in the condition with SOCS- and signal transducer and activator of transcription (STAT) family-deficient and transgenic states were well fitted to ex vivo experimental results for Th1 and Th2 differentiation profiles in the deficient and transgenic mice. The Th0 model suggested the possibility that dominant Th1 differentiation in
STAT4
/STAT6 double-deficient mice may be due to a positive feedback effect of initial IFN-gamma production from T cells. The in silico assessment of beneficial effects of inhibitory drugs by simulation analysis with our Th0 model indicated that
Janus kinase 3
-specific inhibitors might be suitable candidates for the modification of Th2-dominant immune responses. Our results demonstrate that models for the simulation of signaling network, such as our Th0 model, are useful tools for the in silico evaluation of novel drug candidates.
...
PMID:Computer simulation of the role of SOCS family protein in helper T cell differentiation. 1641 Mar 11
Experimental allergic encephalomyelitis (EAE) is a Th1 cell-mediated autoimmune disease model of multiple sclerosis (MS). IL-12 plays a crucial role in the pathogenesis of EAE/MS and inhibition of IL-12 production or IL-12 signaling was effective in preventing EAE. Cyclooxygenase (COX-2) is a key enzyme promoting inflammation in rheumatoid arthritis and tumor induced angiogenesis. Recent studies have shown that COX-2 inhibitors prevent EAE, however, their mechanism of action is not fully understood. In this study, we show that in vivo treatment (i.p.) with 100 mug COX-2 selective inhibitors (LM01, LM08, LM11, and NS398), on every other day from day 0 to 30, significantly reduced the incidence and severity of EAE in SJL/J and C57BL/6 mice. Further analyses showed that the COX-2 inhibitors reduced neural antigen-induced IL-12 production, T cell proliferation and Th1 differentiation ex vivo and in vitro. The COX-2 inhibitors also decreased IL-12-induced T cell responses through blocking tyrosine phosphorylation of
JAK2
,
TYK2
, STAT3, and
STAT4
proteins in T cells. These results demonstrate that COX-2 inhibitors ameliorate EAE in association with the modulation of IL-12 signaling through JAK-STAT pathway leading to Th1 differentiation and suggest their use in the treatment of MS and other Th1 cell-mediated autoimmune diseases.
...
PMID:COX-2 inhibitors modulate IL-12 signaling through JAK-STAT pathway leading to Th1 response in experimental allergic encephalomyelitis. 1641 5
Experimental allergic encephalomyelitis (EAE) is a Th1 cell-mediated autoimmune disease model of multiple sclerosis (MS). Vitamin D deficiency is commonly observed in MS patients and vitamin D supplements reduce the clinical symptoms of EAE and MS. Earlier studies have shown that in vivo treatment with vitamin D analogs ameliorates EAE in association with the inhibition of IL-12 production and Th1 differentiation. The mechanisms in the regulation of Th1 response by vitamin D in EAE/MS are, however, not known. We show that in vivo treatment of C57BL/6 and SJL/J mice (i.p.) with 100 ng of 1,25 dihydroxyvitamin D3, on every other day from Day 0-30, ameliorates EAE in association with the inhibition of IL-12 production and neural antigen-specific Th1 response. In vitro treatment with 1,25(OH)2D3 inhibited IFNgamma-induced tyrosine phosphorylation of STAT1, without affecting
JAK2
, in EOC-20 microglial cells. Treatment of activated T cells with 1,25(OH)2D3 also inhibited the IL-12-induced tyrosine phosphorylation of
JAK2
,
TYK2
, STAT3, and
STAT4
in association with a decrease in T cell proliferation in vitro. These findings highlight the fact that vitamin D modulates JAK-STAT signaling pathway in IL-12/IFNgamma axis leading to Th1 differentiation and further suggest its use in the treatment of MS and other Th1 cell-mediated autoimmune diseases.
...
PMID:1,25 Dihydroxyvitamin-D3 modulates JAK-STAT pathway in IL-12/IFNgamma axis leading to Th1 response in experimental allergic encephalomyelitis. 1654 67
Dendritic cells (DC) constitute a complex system of uniquely specialized antigen-presenting cells (APC) that play crucial roles in the initiation and regulation of immune responses. Recent studies have demonstrated that DC silenced by siRNA IL-12 p35 showed tolerogenic capacity in vitro. However, their mechanism of action is not fully understood. In this study, IL-12p35 siRNA was chemically synthesized and transfected into DCs. A coculture of T cells and DCs was performed. After 30 min coculture, T cells were harvested and analyzed. We showed that the IL-12 p35 silenced DCs decreased IL-12-induced T cell responses through blocking tyrosine phosphorylation of
JAK2
,
TYK2
, STAT3, and
STAT4
proteins in T cells. These results demonstrate IL-12 p35 silenced DCs modulate immune responses by blocking IL-12 signaling through JAK-STAT pathway in T cells.
...
PMID:IL-12 p35 silenced dendritic cells modulate immune responses by blocking IL-12 signaling through JAK-STAT pathway in T lymphocytes. 1719 45
Multiple sclerosis is a chronic inflammatory disease of the CNS. Although progressive axonal injury and diffuse inflammatory damage has been shown in the chronic phase of the disease, little is known about the molecular mechanisms underlying these pathological processes. In order to identify these mechanisms, we have studied the gene expression profile in non-lesion containing tissue, the so-called normal-appearing white matter (NAWM). We performed differential gene expression analysis and quantitative RT-PCR on subcortical white matter from 11 multiple sclerosis and 8 control cases. Differentially expressed genes were further analysed in detail by in situ hybridization and immunofluorescence studies. We show that genes known to be involved in anti-inflammatory and protective mechanisms such as STAT6,
JAK1
, IL-4R, IL-10, Chromogranin C and Hif-1alpha are consistently upregulated in the multiple sclerosis NAWM. On the other hand, genes involved in pro-inflammatory mechanisms, such as
STAT4
, IL-1beta and MCSF, were also upregulated but less regularly. Immunofluorescence colocalization analysis revealed expression of STAT6,
JAK1
, IL-4R and IL-13R mainly in oligodendrocytes, whereas
STAT4
expression was detected predominantly in microglia. In line with these data, in situ hybridization analysis showed an increased expression in multiple sclerosis NAWM of HIF-1alpha in oligodendrocytes and HLA-DRalpha in microglia cells. The consistency of the expression levels of STAT6,
JAK1
,
JAK3
and IL-4R between the multiple sclerosis cases suggests an overall activation of the STAT6-signalling pathway in oligodendrocytes, whereas the expression of
STAT4
and HLA-DRalpha indicates the activation of pro-inflammatory pathways in microglia. The upregulation of genes involved in anti-inflammatory mechanisms driven by oligodendrocytes may protect the CNS environment and thus limit lesion formation, whereas the activation of pro-inflammatory mechanisms in microglia may favour disease progression. Altogether, our data suggests an endogenous inflammatory reaction throughout the whole white matter of multiple sclerosis brain, in which oligodendrocytes actively participate. This reaction might further influence and to some extent facilitate lesion formation.
...
PMID:Normal-appearing white matter in multiple sclerosis is in a subtle balance between inflammation and neuroprotection. 1805 37
Classically, HLA-DR expressed on antigen presenting cells (APC) initiates lymphocyte activation via presentation of peptides to TCR bearing CD4+ T-Cells. Here we demonstrate that HLA-DR alpha 2 domain (sHLA-DRalpha2) also induces negative signals by engaging TIRC7 on lymphocytes. This interaction inhibits proliferation and induces apoptosis in CD4+ and CD8+ T-cells via activation of the intrinsic pathway. Proliferation inhibition is associated with SHP-1 recruitment by TIRC7, decreased phosphorylation of
STAT4
, TCR-zeta chain &
ZAP70
, and inhibition of IFN-gamma and FasL expression. HLA-DRalpha2 and TIRC7 co-localize at the APC-T cell interaction site. Triggering HLA-DR - TIRC7 pathway demonstrates that sHLA-DRalpha2 treatment inhibits proinflammatory-inflammatory cytokine expression in APC & T cells after lipopolysaccaride (LPS) stimulation in vitro and induces apoptosis in vivo. These results suggest a novel antiproliferative role for HLA-DR mediated via TIRC7, revise the notion of an exclusive stimulatory interaction of HLA-DR with CD4+ T cells and highlights a novel physiologically relevant regulatory pathway.
...
PMID:HLA-DR alpha 2 mediates negative signalling via binding to Tirc7 leading to anti-inflammatory and apoptotic effects in lymphocytes in vitro and in vivo. 1827 May 67
Purified protein derivative (PPD) or tuberculin skin testing is used to identify infected individuals with Mycobacterium tuberculosis (Mtb) and to assess cell-mediated immunity to Mtb. In the present study, we compared PBMC cultures in the presence of tuberculin or Candida antigens using cytokine bead arrays and RNA microarrays. Measurements of different cytokines and chemokines in supernatants of PMBC cultures in the presence of PPD showed increased levels of interferon (IFN)-gamma in active tuberculosis infection (ATBI) and latent TB infected (LTBI) compared to controls, and increased levels of TNF-alpha in ATBI compared with LTBI. Also, we found increase of IL-6 in cultures of PPD positive and controls but not in the cultures with Candida. We also report the molecular signature of tuberculosis infection, in ATBI patients, the following genes were found to be up-regulated and absent in LTBI individuals: two kinases (
JAK3
and p38MAPK), four interleukins (IL-7, IL-2, IL-6, and IFNbeta1), a chemokine (HCC-4) a chemokine receptor (CxCR5), two interleukin receptors (IL-1R2 and IL-18R1), and three additional ones (TRAF5, Smad2, CIITA, and NOS2A). By contrast, IL-17 and IGFBP3 were significantly up-regulated in LTBI. And,
STAT4
, GATA3, Fra-1, and ICOS were down-regulated in ATBI but absent in LTBI. Conversely, TLR-10, IL-15, DORA, and IKK-beta were down-regulated in LTBI but not in ATBI. Interestingly, the majority of the up-regulated genes found in ATBI were found in cultures stimulated with tuberculin (PPD) or Candida antigens, suggesting that these pathogens stimulate similar immunological pathways. We believe that the molecular signature distinguishing active from latent tuberculosis infection may require using cytokine bead arrays along with RNA microarrays testing cell cultures at different times following in vitro proliferation assays using several bacterial antigens and PPD.
...
PMID:Molecular signatures distinguishing active from latent tuberculosis in peripheral blood mononuclear cells, after in vitro antigenic stimulation with purified protein derivative of tuberculin (PPD) or Candida: a preliminary report. 1864 50
In this study, we compared the association of several newly discovered susceptibility genes for systemic lupus erythematosus (SLE) between populations of European origin and two Asian populations. Using 910 SLE patients and 1440 healthy controls from Chinese living in Hong Kong, and 278 SLE patients and 383 controls in Thailand, we studied association of
STAT4
,
BLK
and PXK with the disease. Our data confirmed association of
STAT4
(rs7574865, odds ratio (OR) =1.71, P=3.55 x 10(-23)) and
BLK
(rs13277113, OR=0.77, P=1.34 x 10(-5)) with SLE. It was showed that rs7574865 of
STAT4
is also linked to hematologic disorders and potentially some other subphenotypes of the disease. More than one genetic variant in
STAT4
were found to be associated with the disease independently in our populations (rs7601754, OR=0.59, P=1.39 x 10(-9), and P=0.00034 when controlling the effect of rs7574865). With the same set of samples, however, our study did not detect any significant disease association for PXK, a risk factor for populations of European origin (rs6445975, joint P=0.36, OR=1.06, 95% confidence interval: 0.93-1.21). Our study indicates that some of the susceptibility genes for this disease may be population specific.
...
PMID:Population differences in SLE susceptibility genes: STAT4 and BLK, but not PXK, are associated with systemic lupus erythematosus in Hong Kong Chinese. 1922 26
<< Previous
1
2
3
4
5
6
7
8
9
Next >>