约氏疟原虫感染早期易感和抵抗小鼠树突状细胞细胞因子的分泌特点

Dendritic Cell Cytokine Secretion Characteristics of Susceptible and Resistant Mice during the Early Phase of Plasmodium yoelii Infection

目的探讨在致死型约氏疟原虫（P.y17XL）感染早期,树突状细胞（DC）调控Th1细胞免疫应答的相关机制。方法用P.y17XL感染BALB/c和DBA/2小鼠,计数红细胞感染率;感染前和感染后3和5d制备脾细胞悬液,磁珠分选、纯化DCs并体外培养;ELISA方法检测DCs培养上清中IL-12p40、IL-10和TGF-β1的水平。结果DBA/2小鼠DCs培养上清中IL-12p40的水平在感染后3~5d明显升高,与感染前相比具有统计学意义;而BALB/c小鼠DCs培养上清中IL-12p40的水平始终未见明显升高;两种小鼠DCs培养上清中IL-10和TGF-β1水平在感染后3~5d均明显升高,但BALB/c小鼠DCs培养上清中IL-10和TGF-β1水平明显高于DBA/2小鼠。结论P.y17XL感染早期,BALB/c和DBA/2小鼠在DCs细胞因子的分泌模式上存在显著差异。

Objective To investigate the related mechanism of dendritic cells （DCs） regulating the Thl immune response during early Plasmodium yoelii 17XL （P.y 17XL） infection. Methods BALB/c mice and DBA/2 mice were infected by intraperitoneal injection with 1×l0^6 virulent P.y 17XL parasitized erythrecytes; the ratio of infected RBC was counted. On day 0,3 and 5 post infection （p.i.）,spleen cell suspension was prepared,DCs were purified by magnetic separation and cultured in vitro. The levels of IL-12p40,IL-10 and TGF-β1 in DC supematants were dynamically detected by ELISA. Results It was found that the levels of IL-12p40 showed obvious increases on day 3-5 p.i. in DBA/2 mice,which has statistical significance comparing with the pre-infecfion. However,a continuously increased levels of IL-12p40 were not observed from day 3 to 5 p.i. days in BALB/c mice. The levels of IL-10 and TGF-β1 in DCs supematants showed obvious increases on day 3-5 p.i. in BALB/c mice and DBA/2 mice. But the levels of BALB/c mice were higher than those of DBA/2 mice. Conclusion These results indicate that there are significant differences in cytokine profile of DCs in BALB/c and DBA/2 mice during the early stages of P.y 17XL infection.