The alteration of Th17 cells and CD4+CD25+FoxP3+ regulatory T cells in patients with ankylosing spondylitis

Objective To investigate the percentages of Th17 and CD4+CD25+FoxP3+ regulatory T(Tr) cells and the levels of related cytokines IL-6,IL-23,IL-17 and TGF-β in serum of patients with anlylosing spondylitis(AS).Methods Forty patients with AS and 37 age-matched healthy donors were studied.Flow cytometry Was used to analyze the percentages of blood Th17 and CD4+CD25+FoxP3+Tr cells.The levels of serum IL-6,IL-23,IL-17 and TGF-β were assayed by enzyme-linked immunosorbent assay ( ELISA).Results The proportion of Th17 cells in AS group was significantly higher than those in normal group [ (1.02±0.34)％ vs (0.68±0.29)％,P＜0.05) ],and the proportion of CD4+CD25+FoxP3+ cells was lower in AS group comparing with normal group [(3.77±0.81)％ vs (4.69±1.23)％,P＜0.05)].Meanwhile,serum levels of IL-6,IL-23 and IL-17 were significantly higher in AS group than those in normal group [ (6,15±2.71) ng/L vs (3.31±1.65) ng/L; (9.44±3.12) ng/ml vs (5.82±2.61) ng/ml;(10.53±4.97) ng/L vs (6.78±3.26) ng/L,all P＜0.01 ].In contrast,TGF-β level was decreased in AS group compares with the normal group [ ( 4.76±2.15) ng/ml vs (5.16±2.02) ng/ml,P＞0.05 ],but the difference was not significant.No associations of serum eytokine levels with clinical and laboratory parameters were found in AS.Conclusion The abnormality Th17 cells and Tr cells and their related cytokines IL-6,IL-23,IL-17 and TGF-β changes in patients with AS,which may be involved in immunological pathogenesis of AS. Key words: Ankylosing spondylitis, Th17 cells;  Regulatory T cells;  IL-6;  TGF-β