目的建立DBA/1J小鼠胶原诱导性关节炎(collagen-induced arthritis,CIA)模型,从形态学、病理学及免疫学等多方面对该模型进行鉴定。方法将牛Ⅱ型胶原(typeⅡcollagen,CⅡ)与佐剂混合并充分乳化,于DBA/1J小鼠尾根部皮下注射进行初次免疫,21 d后同样的方法进行再次免疫。观察小鼠体重变化、关节肿胀程度等形态学指标,进行踝关节病理检查,并用CBA法检测血清中细胞因子的水平。结果造模组小鼠体重于首免后35 d开始下降并持续低于对照组。于28 d,造模组小鼠出现足爪红肿,35 d足爪肿胀厚度显著高于对照组(P〈0.05),至62 d发病率高达90%。病理学检测显示,造模组小鼠关节腔变窄,滑膜组织增生,炎症细胞浸润,软骨结构不同程度破坏。相比于对照组,造模组小鼠血清中炎性因子IL-6、IFN-γ、MCP-1显著升高(P〈0.05),而抗炎因子IL-10轻微下降(P〉0.05)。结论 DBA/1J小鼠尾根部皮下注射牛Ⅱ型胶原可成功诱导CIA模型。
Objective To establish a DBA/1J mouse model of collagen-induced arthritis (CIA) and to character-ize the pathological and immunological changes of the model. Methods Bovine typeⅡcollagen ( CⅡ) was emulsified in complete Freund's adjuvant (CFA), subcutaneously injected at the root of tail of DBA/1J mice for primary immunization, and the injection was repeated 21 days later for secondary immunization. The changes of body weight, degree of joint swell-ing and other morphological indicators of arthritis were observed and pathological changes in the ankle joints were analyzed. The serum levels of inflammatory cytokines were detected by cytometric bead assay ( CBA) . Results The body weight of the CIA mice began to decrease 35 days after primary immunization and was continuously lower than that in the control group. 28 days after the primary immunization, their paws began to tern red and swollen, and after 35 days, the thickness of swol-len paws of the CIA mice was significantly greater than that in the control group (P 〈0. 05). The incidence rate of CIA reached 90% on the 62nd day. Pathological examination showed a narrowed articular space, hyperplasia of synovial tissue, inflammatory cell infiltration and varying degrees of cartilaginous damage. Compared with the control group, the serum lev-els of inflammatory cytokines IL-6, IFN-γand MCP-1 were significantly increased in the CIA mice (P〈0. 05), while the anti-inflammatory cytokine IL-10 was slightly decreased ( P〉0. 05 ) . Conclusions A collagen-induced arthritis model can be successfully established by subcutaneous injection of bovine collagen typeⅡemulsified in complete Freund' s adju-vant at the root of tail of DBA/1J mice, and provides a useful experimental tool for further studies of pathogenesis of and drug development for rheumatoid arthritis.