重组人肿瘤坏死因子受体融合蛋白诱导胶原诱导型关节炎大鼠滑膜细胞凋亡的研究

 目的胶原诱导大鼠类风湿性关节炎(CIA)为动物模型,探讨重组人肿瘤坏死因子受体融合蛋白(rhTNFR:Fc)对CIA滑膜细胞凋亡的影响。方法Wistar大鼠模型随机分组,rhTNFR:Fc组和甲氨喋呤(MTX)阳性对照组按1.75mg·kg^-1剂量每日皮下注射给药,阴性对照组和正常对照组皮下注射等量生理盐水,31d后抽取膝关节滑液以ELISA法测定TNF-α水平;膝关节滑膜作苏木素-伊红染色(HE)、电镜、缺口末端标记法(TUNEL)标记检测凋亡。结果电镜下可见早期滑膜凋亡细胞,MTX组和rhTNFR:Fc组滑膜细胞凋亡数与阴性对照组比较明显增加,突变型p53的表达被明显抑制,P<0.05;MTX组和rhTNFR:Fc组膝关节滑液TNF-α、NO水平显著下降,与阴性对照组比较差异具显著性,P<0.01。结论首次阐明rhTNFR:Fc诱导CIA大鼠滑膜细胞凋亡,抗类风湿性关节炎可能通过下调p53,降低TNF-α、NO来诱导滑膜细胞凋亡,减轻CIA大鼠的关节炎症。

Study on rhTNFR:Fc Induced Apoptosis of Synovial Membrane Cell in Collagen Induced Arthritis Rats

OBJECTIVE To investigate the rhTNFR:Fc induced apotosis of synoviocytes in collagen induced arthritis(CIA) rat model.METHODS The rats in rhTNFR:Fc and MTX group(positive control) were administered with rhTNFR:Fc at 1.75 mg per 1 kg everyday.The rats in negtive control and blank control group were administered with 0.9% NS everyday.The rats were killed on the 31st d after drug administration,and the rat knee joints synovium were studied by pathology,electron microscopy and TUNEL.The NO level and TNF-α concentration in synovial fluid of each group were measured.RESULTS Under the electron microscopy,early phase apoptotic synoviocytes were observed.The difference of apoptotic rate between the rhTNFR:Fc group and the negative group was significant(P<0.01).The NO level and TNF-α concentration from synovial fluid were significantly reduced in the rhTNFR:Fc group.The number of synoviocytes apoptosiss was increased.MTX and rhTNFR:Fc increased the number of synoviocytes apoptosis as well as inhibited p53 mutation expression(p<0.05).CONCLUSION rhTNFR:Fc could induce the apoptosis of synoviocytes in CIA rats,which might be one of mechanisms of rhTNFR:Fc in treating rheumatoid arthritis.rhTNFR:Fc might down-regulate p53 mutation expression and induce apoptosiss of synoviocytes by which it could relieve joint inflammation of CIA rats.