夏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

目的探讨在夏氏疟原虫(Plasmodiumchabaudi chabaudi AS,P.c.chabaudi AS)感染早期,树突状细胞(Den-dritic cells,DCs)调控Th1细胞免疫应答的相关机制。方法用P.c.chabaudi AS感染易感型DBA/2和抵抗型BALB/c小鼠,计数红细胞感染率;感染前和感染后3、5、8d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3-8天明显升高,BALB/c小鼠DCs培养上清中IL-12p40的水平在感染后5-8d出现有意义的升高,但其水平均明显低于DBA/2小鼠;两种小鼠DCs培养上清中IL-10与TGF-β1的分泌水平在感染后5-8d明显升高,但DBA/2小鼠DCs培养上清中IL-10与TGF-β1的分泌水平明显低于BALB/c小鼠。结论 P.c.chabaudi AS感染早期,DBA/2和BALB/c小鼠在DCs细胞因子的分泌模式上存在显著差异。

Dendritic cell cytokine secretion in susceptible and resistant mice during the early phase of Plasmodium chabaudi chabaudi AS infection

To investigate the related mechanism of dendritic cells（DCs） regulating Thl immune response during early Plasmodium chabaudi chabaudi AS（P.c.chabaudi AS） infection,the susceptible DBA/2 mice and resistant BALB/c mice were infected by intraperitoneal injection of 1 106 P.c.chabaudi AS parasitized erythrocytes.Parasitemia of individual mice was monitored by microscopic examination of Giemsa-stained blood smear.Spleen cell suspension was prepared from the mice sacrificed on days 0,3,5,8 post infection（p.i.）,while DCs were purified by magnetic separation and cultured in vitro.The levels of IL-12p40,IL-10 and TGF-（l in DCs supernatants were dynamically detected by ELISA.The level of IL-12p40 in DCs supernatants showed obvious increases on day 3-8 p.i.in DBA/2 mice,while significantly elevated on day 5-8 p.i.in BALB/c mice.Moreover,the level of IL-12p40 in BALB/c mice was significantly lower than that in DBA/2 mice from day 3 to 8 p.i..Levels of IL-10 and TGF-（l in DCs supernatants showed obvious increases on day 5-8 p.i.in BALB/c and DBA/2 mice.But the levels for DBA/2 mice were lower than those of BALB/c mice.These results indicated that there are significant differences in cytokine secretion profile of DCs in BALB/c and DBA/2 mice during the early stages of P.c.chabaudi AS infection.