RANKL／骨保护素在类风湿关节炎患者血清及T细胞上的表达及临床意义

Variation of RANKL/OPG in serum and T lymphocytes of patients with rheumatoid arthritis and theirclinical significance

目的研究类风湿关节炎（RA）患者激活T细胞膜结合型核因子-（B活化因子受体配体（mRANKL）表达率及血清、培养上清中可溶性核因子KB活化因子受体配体（sRANKL）和骨保护素水平，探讨RANKL／RANK／OPG系统与RA骨破坏的关系。方法RA患者和健康对照外周血单个核细胞（PBMC）体外培养72h获得激活淋巴细胞，采用流式细胞术检测CD3＋mRANKL＋T细胞的表达率，采用酶联免疫吸附试验（ELISA）法检测血清和培养上清中sRANKL、骨保护素水平，同时记录各患者临床和实验室指标，应用t检验及多元线性回归对各组数据进行分析。结果RA患者和健康对照激活T细胞mRANKL表达率差异无统计学意义[（14±4）％与（15±7）％，P〉0．05]。与健康对照组相比，RA患者血清sRANKL[（133±49）与（41±8）pmol／L，P〈0．05]、骨保护素[（390±154）与（222＋38）pg／ml，P〈O．05]、sRANKL／骨保护素[（0．40±0．23）与（0．19±0．05），P〈0．05]升高；RA患者培养上清sRANKL[（34±19）与（17＋5）pmol／L，P〈0．05]、sRANKU骨保护素[（0．39士o．23）与（0．19±O．05），P〈O．05]升高。多元线性回归发现血清骨保护素水平与28关节疾病活动指数（DAS28）呈负相关（屉-0．681，t=3-315，P=-0．005）；血清sRANKU骨保护素比值与抗环瓜氨酸肽（CCP）抗体呈正相关（百=0．497，t=2．326，P=0．040）；RA患者双手关节Sharp评分与mRANKL（β=0．522，拉2．370，P=0．032）、HAQ（／3=O．559。t=2．536，P=0．023）呈正相关。结论RA患者T细胞膜上mRANKL脱落异常可能是其出现骨破坏的另一免疫学机制。RA患者激活T细胞mRANKL表达率是RA骨破坏的危险因素。抗环瓜氨酸肽（CCP）抗体阳性的RA患者具有更明显骨侵蚀，可能与RANKURANⅪ骨保护素系统有关。

Objective To detect the positive expression level of CD3± mRANK± cells in the peripheral blood and the level of sRANKL and OPG in serum and culture supernatant of patients with rheumatoid arthritis （RA） and investigate the association between RANKL/RANK/OPG system and the destruction of RA. Methods Twenty-four RA patients and 20 healthy controls were collected in the Rheumatology and Immunology Department of the First Affiliated Hospital of Anhui Medical University. The peripheral blood mono- nuclear cell （PBMC） were extracted, subsequently stimulated in vitro with PHA for 72 hours. Flow cytometry （FCM） was used to detect the positive expression level of CD3＋ mRANK＋ cells in the peripheral blood, and ELISA was used to detect the level of sRANKL and OPG in serum and culture supernatant. Clinical and laboratory parameters were recorded. Multivariate linear regression and t-test were used to analyze the data from different groups. Results There was no statistical sigr/ificant difference in the expression level of CD3＋ mRANK± cells [（14±4）% vs （15±7）%, P〉0.05] in RA patients compared with that in healthy controls. Compared with healthy controls, the level of sRANKL[（133±49） vs （41±8） pmol/L, P〈0.05], OPG[（390± 154） vs （222±38） pg/ml, P〈0.05] and sRANKL/OPG [（0.40 ＋0.23） vs （0.19±0.05）, P〈0.05] increased in the serum of RA patients. The level of sRANKL [（34±19） vs （17±5） pmol/1, P〈0.05] and sRANKL/OPG [ （0.39±0.23） vs （0.19 ±0.05）, P〈0.05 ] increased in culture supernatant of RA patients. Multivariate linear regression showed that there was a negative correlation between DAS28 and the level of OPG in serum in RA （β=-0.681, t=3.315, P=0.005）.There was a positive correlation between anti-CCP and sRANKL/OPG ratio in serum in RA（β=0.497, t=2.326, P=0.040）. There was a negative correlation between mRANKL and the Sharp method （β=0.522, t=2.370, P=0.032）. There was a negative correlation between HAQ and the Sharp method （β =0.559, t =2.536, P=0.023）. Conclusion Abnormality of RANKL shedding of T lymphocytes may be another inmmune machanism for the bone destruction of RA. The level of mRANKL expressed by activated T cell is a risk factor for the severity of bone damage of RA.In the bone destruction of RA,Anti-CCP antibody and RANKL/RANK/OPG system may be closely related.