Abstract:In order to explore the effect and mechanism of cytotoxic T-lymphocyte-associated protein 4 (CTLA-4) on the immune evasion of Schistosoma japonicum (S. japonicum) in mice, the 18 female BALB/c mice were divided randomly into 3 groups: normal control, infected control and anti-CTLA-4 mAb-treated group. Each mouse in infected control and anti-CTLA-4 groups was challenged with 40 cercarie of S. japonicum. Mice in anti-CTLA-4 mAb group were treated with 300 μg of anti-CTLA-4 mAb for 3 days consecutively, equal volume PBS as control. At 6 weeks post-infection, all mice were succumbed to measure worm burden and eggs per gram liver. The levels of IFN-γ, IL-4, IL-5 and IL-10 were detected by sandwich-ELISA. Flow cytometry was performed to measure the percentages of CD4+CD25+ tregs in splenic cells. Liver sections were stained with hematoxylin and eosin to detect egg granuloma. The results showed that reduction rate of worm burden in anti-CTLA-4 mAb group were 18.99%. Compared with that of control group, the percentage of CD4+CD25+ Tregs was extremely higher in anti-CTLA-4 mAb group. The egg granuloma size in anti-CTLA-4 mAb group were extremely larger than those of infected control group, while the levels of IFN-γ, IL-4, IL-5, IL-10 in anti-CTLA-4 mAb group were extremely higher than those of control group. It’s indicated that anti-CTLA-4 mAb favors the host to clear S. japonicum by enhancing Th1 type immune response, but at the cost of elevated pathological damage by enhancing Th2 type immune response. It hints that CTLA-4 contribute to the escape of S. japonicum from the host immune responses.
唐春莲, 申志琴, 严玲霞, 刘晓宏. 细胞毒性T淋巴细胞相关蛋白4在日本血吸虫免疫逃避中的作用及其机制研究[J]. 中国人兽共患病学报, 2015, 31(11): 1061-1064.
TANG Chun-lian, SHEN Zhi-qin, YAN Lin-xia, LIU Xiao-hong. Effect and mechanism of CTLA-4 on the immune evasion of Schistosoma japonicum in mice. Chinese Journal of Zoonoses, 2015, 31(11): 1061-1064.
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