p47 GTP酶在日本血吸虫感染中的应答特征

Immune response characteristics of p47 GTPases to Schistosoma japonicum infection

目的建立日本血吸虫感染小鼠模型,研究IGTP和IRG-47在日本血吸虫感染中的作用特点及参与免疫应答的能力。方法以IGTP基因敲除(IGTP KO)小鼠、IRG-47基因敲除(IRG-47KO)小鼠和野生型C57BL/6J小鼠(WT)为研究对象,建立日本血吸虫感染实验模型。感染10周后计数成虫数和虫卵数,以HE染色观察肝脏的病理变化,以间接ELISA法检测血清中日本血吸虫特异性IgG抗体,以RTQ-PCR检测脾细胞中细胞因子和趋化因子的mR-NA表达水平。结果日本血吸虫感染10周后,IGTP KO小鼠与WT小鼠虫荷数和卵荷数差异无统计学意义(P<0.05),IRG-47KO小鼠的虫荷数和卵荷数均低于IGTP KO和WT小鼠。IRG-47KO组小鼠肝脏单个虫卵肉芽肿面积显著小于IGTP KO组和WT组(P<0.05)。日本血吸虫感染10周后,IGTP KO小鼠SWAP和SEA特异IgG2a水平高于IRG-47KO小鼠和WT小鼠(P<0.05);IGTP KO小鼠脾细胞il12、il4mRNA表达高于WT小鼠(P<0.05),且if-ng表达高于IRG-47KO小鼠(P<0.05);IRG-47KO小鼠趋化因子ccl3、cxcl9、cxcl10mRNA表达显著低于IGTP KO小鼠和WT小鼠(P<0.05)。结论 IRG-47缺失对日本血吸虫感染有一定保护作用,IRG-47KO小鼠肝脏病理特征与其趋化因子的表达相一致。

Objective To investigate the immune response characteristics of IGTP and IRG 47 to Schistosorrla japoni cure infection. Methods In an infection model, IGTP knockout （IGTP KO） mice, IRG-47 knockout （IRG 47 KO） mice, and wild-type （WT） C57BL/J mice were exposed to 14 S. japonicum cercariae via the pinna and sacrificed 10 weeks post-infection. The worm burden was determined by perfusion of the portal system. Weighed liver samples except the left front lobe from individual mice were digested in 5~ KOH at 37~C overnight. The released eggs were microscopi- cally counted. The left front lobe of each liver was stained with hematoxylin-eosin （HE） to detect pathological lesions. SWAP-specific and SEA-specific lgG antibodies in sera were detected using indirect EIASA. Levels of mRNA expression of cytokines （ifng, i112, i14, and i110） and chemokines （eel3, cxcl9 and cxcll0） in spleen cells were determined using quantitative real-time PCR. Results No significant differences in the number of adult worms and liver eggs were noted in infected IGTP KO mice and WT mice. However, there was a marked decrease in adult worms and egg counts in the liv- ers from infected IRG-47 KO mice compared to the other two groups. The average area of a single-egg granuloma in IRG- 47 KO mice was smaller than that in IGTP KO mice and WT mice. SWAP-specific and SEA specific IgG2a antibody levels in sera from IGTP KO mice 10 weeks post-infection were higher than those from IRG-47 KO and WT mice. The expres sion of i112 and i14 mRNA in IGTP KO mice spleen cells was higher than that in WT mice, and the expression of ifng in IGTP KO mice spleen cells was higher than that in IRG-47 KO mice. The level of mRNA expression of chemokines （cc13, cxcl9 and cxcll0） in IRG-47 KO mice spleen cells was significantly lower than that in IGTP KO mice and WT mice. Con clusion IRG 47 deletion may play a protective role in S. japonicum infection, and the pathological features of the liver in IRG 47 KO mice may be related to chernokine expression.