端粒保护蛋白TPP1及POT1在类风湿关节炎滑膜成纤维细胞的变化及临床意义

Changes of TPPI and POT1 in fibroblast-like synovial cells might be involved in the pathogenesis of rheumatoid arthritis

目的探讨端粒保护蛋白TPP1及POT1在类风湿关节炎（RA）发病机制中可能的作用。方法体外培养纤维滑膜细胞（SFs）用实时荧光定量聚合酶链反应（PCR）法检测42例RA、23例骨关节炎和13例外伤截肢患者（对照组）SFsTPPl、POTlmRNA的表达水平，蛋白印迹法检测RA、骨关节炎及健康对照SFs个各8例TPPl、POTl蛋白水平；多组间变量的差异用单因素方差分析，变量间的相关关系采用Spearman相关分析。结果TPPl、POTlmRNA在RA组SFs的表达低于骨关节炎组及对照组（TPP1：0．006±0．003，O．179±0．077，0．189±0．027，POTl：0．006±0．003，0．063±0．027，0．072±0．006；P均〈O．01），骨关节炎组和对照组间差异无统计学意义（P〉O．05）。TPPl蛋白在RA组的表达显著低于骨关节炎组和对照组（0．225±0．018，0．632±0．030，0．651±0．038；P〈0．01），骨关节炎组和对照组间差异无统计学意义（P〉0．05）；POTl蛋白在3组间差异无统计学意义（伶O．05）。rIPPlmRNA表达量与RA患者抗环瓜氨酸肽抗体及类风湿因子呈负相关（P均（0．05），与疾病活动评分、红细胞沉降率、血清c反应蛋白无相关性（P均〉O．05）；TPPl、POTl蛋白表达量及POTlmRNA表达量与上述指标均无相关性（P均〉0．05）。结论端粒保护蛋白TPPl、POTl的降低可能在RA患者SFs出现转化细胞特性中发挥重要作用；TPPl转录及蛋白水平的降低可能与RA出现关节侵蚀性改变密切相关。

Objective To determine whether changes of telomeric proteins TPP1 and POT1 in synovial fibroblasts （SFs） might participate in the pathogenesis of rheumatoid arthritis （RA）. Methods SFs were isolated from patients with RA, osteoarthritis （OA） and traumatic joint disease, and cultured in vitro. TPP1 and POT1 mRNA level of SFs was measured using real-time quantitative polymerase chain reaction （RT- qPCR） in 42 RA, 23 OA and 13 conrtal cases. Western blotting was used to detect the expression of TPP1 and POT1 protein. One-way analysis of variance and Spearman＇s rank correlation test were performed. Results Expression of TPP1 and POT1 mRNA was significantly reduced in RA cases （TPP1 ： 0.006 ± 0.003, 0.179±0.077, 0.189±0.027; POTI： 0.006±0.003, 0.063±0.027, 0.072±0.006, P〈0.01; respecti-vely）, no significant difference was observed between OA and conrtal cases （P〉0.05, respectively）. Western blotting demonstrated that TPP1 protein level was significantly reduced in RA cases （0.225±0.018, 0.632±0.030, 0.651±0.038; P〈0.01）, POT1 protein expression was not statistically significant among RA, OA patients and conrtal subjects （P〉0.05）. Significant negative correlation was observed between levelly of TPP1 mRNA and titers of anti-CCP antibody , RF （P〈0.01）. Conclusion Changes of TPP1 and POT1 might contribute to persistent proliferation of SFs in RA.