日本血吸虫副肌球蛋白全基因核酸疫苗对小鼠的抗病免疫效应

目的 探讨日本血吸虫副肌球蛋白全基因核酸疫苗（Sjc97 DNA）免疫小鼠诱导的抗病免疫效应。 方法 将40只C57BL/6小鼠随机分成4组：疫苗组,以Sjc97 DNA疫苗100 μg经后腿胫前肌注射免疫小鼠,共2次,间隔3周;空质粒组,以同法、同剂量的空质粒载体免疫小鼠;上述2组分别于末次免疫后3周攻击感染30±2条日本血吸虫尾蚴;感染对照组,不作免疫,感染相同数量的日本血吸虫尾蚴;空白对照组,未作任何处理。攻击感染后7周剖杀小鼠,测量肝脏单个虫卵肉芽肿大小,测定鼠血清透明质酸及层黏连蛋白含量,PCR?鄄ELISA检测肝组织转化生长因子（TGF-β1） mRNA的表达水平。 结果 Sjc97 DNA疫苗组小鼠肝脏虫卵肉芽肿的直径为（183.75±42.36）μm,显著小于空质粒对照组的（303.12±37.36）μm和感染对照组的（304.38±53.23）μm （P<0.01）。血清透明质酸和层黏连蛋白水平,疫苗组显著低于感染对照组（P<0.01）。肝组织TGF-β1 mRNA表达水平,疫苗组亦明显低于两对照组（P<0.05）。 结论 Sjc97 DNA核酸疫苗具有一定的抗虫卵肉芽肿及抗肝纤维化作用。

Anti-Schistosomiasis Effect Induced by Full Length DNA Vaccine Coding Paramyosin of Schistosoma japonicum in C57BL/6 Mice

OBJECTIVE: To observe the anti-schistosomiasis effect in mice immunized with Sjc97 DNA vaccine. METHODS: C57BU6 mice were vaccinated intramuscularly with the Sjc97 DNA twice at an interval of 3 weeks, and challenged with 30 +/- 2 cercariae of Schistosoma japonicum three weeks after immunization. Mice in blank plasmid vector control and infection control groups were also infected with same number of cercariae. The mice were sacrificed 7 weeks after challenge infection. The size of single egg granulomas in livers was measured with micrometer. The level of hyaluronic acid (HA) and laminin (LN) in sera of the mice was determined by ELISA. PCR-ELISA was used to examine the expression of TGF-beta1 mRNA in liver. RESULTS: The mean hepatic egg granuloma diameters of the three groups, the Sjc97 DNA, blank plasmid vector and infection control, were 183.75 +/- 42.36 microns, 303.12 +/- 37.36 microns and 304.38 +/- 53.23 microns, respectively. The hepatic granuloma was significantly smaller in the Sjc97 DNA group than that in control. The level of HA and LN in sera of Sjc97 DNA vaccinated mice was markedly lower than those in the two control groups (P < 0.01). The amount of TGF-beta1 mRNA isolated from the livers of mice in Sjc97 DNA group decreased significantly. CONCLUSION: The results showed that Sjc97 DNA vaccine may act as an effective inhibitor against formation of egg granuloma and reduce immunopathological damage caused by Schistosoma japonicum in the host.