目的初步探讨由CD28和CD40L介导的协同刺激信号在衣原体感染中的作用。方法用1×104IFUs的沙眼衣原体鼠生物型(MoPn)经生殖道感染雌性C57BL/6 J野生型(wt)、CD28 KO、CD80/CD86 KO、CD40L KO及CD40 KO小鼠,免疫荧光法测定生殖道分泌物中衣原体包涵体的数量。初次感染后80天和115天,处死小鼠,分离生殖道,做病理检查;用衣原体EB刺激脾细胞,测定特异性细胞免疫应答水平。结果 CD40LKO及CD40 KO小鼠阴道带菌时间比wt、CD28 KO及CD80/CD86 KO组明显延长;而CD28 KO及CD80/CD86 KO小鼠在初次感染衣原体后,生殖道病理变化比其他组轻。脾细胞因子水平显示,CD40L KO及CD40 KO组IFN-γ产生量较其它组低。结论不同的协同刺激信号在抗衣原体感染中发挥不同的作用,其中CD28分子与保护性免疫无关,但与炎症损伤反应有关;而CD40L-CD40介导的协同刺激信号与衣原体保护性免疫有关。 Objective To investigate the role of CD28 and CD40L-mediated costimulatory signals in Chlamydial infection. Methods Female C57BL / 6 J wild type (wt), CD28 KO, CD80 / CD86 KO, CD40L KO and CD40 KO mice were inoculated via genital tract with 1 × 104 IFNs of C. trachomatis murine biotype (MoPn) Road secretions in the number of chlamydial inclusion bodies. The mice were sacrificed 80 days and 115 days after the first infection and the reproductive tract was isolated for pathological examination. Splenocytes were stimulated with Chlamydia EB, and the level of specific cellular immune responses was measured. Results The vaginal delivery time of CD40LKO and CD40 KO mice was significantly longer than that of wt, CD28 KO and CD80 / CD86 KO groups. However, the pathological changes of genital tract in CD28 KO and CD80 / CD86 KO mice were lighter than those in other groups. Splenic cytokines levels showed that IFN-γ production was lower in CD40L KO and CD40 KO than in other groups. Conclusions Different costimulatory signals play different roles in anti-Chlamydia infection, of which CD28 molecule is not involved in protective immunity but is related to inflammatory response. CD40L-CD40-mediated costimulatory signal is associated with protective immunity of Chlamydia.