中文摘要：

目的检测类风湿关节炎（RA）患者血清中自细胞介素-21（IL-21）的水平，分析其临床意义。方法收集RA患者76例，采用双抗体夹心酶联免疫吸附试验（ELISA）检测RA患者及37例正常对照者血清IL-21水平，并分析血清IL-21水平与RA各临床及实验室指标的相关性。计量资料的比较采用Mann-WhitneyU检验或单因素方差分析，相关性分析采用Spearman相关分析。结果RA患者血清IL-21水平为86．5（64．1～130．1）pg／ml，明显高于正常对照组[65．0（40．0～90．3）pg／ml]，差异有统计学意义（U=957．5，P=0．006）；类风湿因子（av）三个亚型IgM、IgA、IgG及抗环瓜氨酸肽（CCP）抗体阳性组RA患者血清IL-21水平与其自身抗体均呈正相关（r分别为0．300、0．382、0．370、0．372；P均〈0．05）。RA患者RF（IgM、IgA）、CCP抗体阳性组血清IL-21水平显著高于阴性组[82．2（57．0—126．1）pg/ml]和76．9（52．0—201．4）pg／ml，U=176．5，P=0．024；95．4（62．1～144．6）pg／ml和70．6（43．0～110．8）pg／ml，U=282．5，P=0．016；82．9（51．0～145．1）pg/ml和76．5（63．4-144．6）pg/ml，U=333．0，P=0．031]，差异有统计学意义。患者血清IL-21水平与触痛关节数（TEN28）及肿胀关节数（SW28）均呈正相关（r分别为0．342、0．200；P均〈0．05），但IL-21与DAS28评分、C-反应蛋白、血沉、年龄、病程等均无明显相关性。结论IL-21在RA患者血清中高表达，并与RF、抗CCP抗体密切相关．提示IL-21可能是RA发病机制的环节之一。

英文摘要：

Objective To measure serum IL-21 levels of patients with rheumatoid arthritis （RA）, and analyze their clinical significances. Methods The sera from 76 RA patients and 37 normal controls were selected. Serum IL-21 levels of the two groups were detected by enzyme -linked immunosorbent assay （ELISA）. The correlations between serum IL-21 levels and clinical and laboratory parameters of RA patients were investigated . Mann-Whitney U test or One-Way ANOVA and spearman correlation analysis were used for statistical analysis with software SPSS 17. 0. Results Serum IL-21 levels in RA patients [ 86. 5 （64. 1 - 130. 1 ） pg/ml ] were significantly higher than that of the normal controls [ 65.0 （40. 0 - 90. 3 ） pg/ml, U = 957. 5, P =0. 006 ]. In rheumatoid factor （RF） -IgM, RF-IgA, RF-IgG and anti-cyclic citrullinated peptide antibodies （anti-CCP）positive groups, serum IL-21 levels in RA patients were positively correlated with these antibodies （ r = 0. 300,0. 382,0. 370,0. 372, P 〈 0. 05 ）. Serum IL-21 levels were remarkably higher in RF-IgM, RF-IgA, RF-CCP positive groups than in the negative [ 82. 2 （57.0 - 126. 1 ）pg/ml vs. 76. 9（52. 0 -201.4） pg/ml, U= 176.5 ,P =0. 024 ;95.4（62. 1 - 144. 6） pg/ml vs. 70. 6（43.0 - 110. 8 ） pg/ml, U = 282. 5, P = 0. 016 ;82. 9 （51.0 - 145. 1 ） pg/ml vs. 76. 5 （ 63.4 - 144. 6 ） pg/ml, U = 333.0, P = 0. 031 ]. Also, serum IL-21 levels in RA patients were positively correlated with tenderness of joint number in 28 joints （ TEN28 ） and swelling of joint number in 28 joints （ SW28 ） （ r = 0. 342, O. 200, P 〈 0. 05 ）. However, serum IL-21 levels in RA patients were no significantly correlation with DAS 28 score, C-reaction protein, erythrocyte sedimentation rate, age or duration. Conclusions Serum IL-21 levels are significantly elevated in RA and associated with RF and anti -CCP antibodies ,which could be a part link of the pathogenesis of RA.