Background Our previous research has demonstrated decreased expression of CD4+CD25+Foxp3+ regulatory T cells (Tregs) enrolled in the pathogenesis of rheumatoid arthritis (RA). Anti-TNF-α mAb therapy could improve Tregs expansion in RA and associate with clinical amelioration of RA patients. STAT5 is reported to have effects on many aspects of immune function, particularly in regulatory T cell development.
Objectives In this study, we aim to monitor phosphoSTAT5 expression in Tregs and investigate its role in RA disease.
Methods Flowcytometry was employed to detect the phosphorylation level of STAT5 in CD3+CD4+ T cells, CD4+CD25high regulatory T cells and the expression of CD4+CD25+Foxp3+Tregs in peripheral blood of 20 patients with RA disease and 20 age and gender-matched normal controls. STAT5 mRNA expression in peripheral blood mononuclear cells (PBMC) were also monitored of these RA patients and normal controls.
Results Phosphorylation level of STAT5 deceased in RA patients both in CD3+CD4+ T cells and in CD4+CD25high regulatory T cells, along with reduction of expression of CD4+CD25+Foxp3+ Tregs. Detection of mRNA also confirmed STAT5 down regulation in Tregs in RA patients.
Conclusions Compared with normal controls, the expression of CD4+CD25+Foxp3+Tregs decreased in RA patients. PhosphoSTAT5 reduction in CD3+CD4+ T cells, mainly in CD4+CD25high regulatory T cells contributed to impairment of CD4+CD25+Foxp3+ regulatory T cells in RA.
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Huang Z, Yang B, Shi Y, Cai B, Li Y, Feng W, Fu Y, Luo L, Wang L. Anti-TNF-α therapy improves Treg and suppresses Teff in patients with rheumatoid arthritis. Cell Immunol. 2012 Sep;279(1):25–9.
Disclosure of Interest None declared