日本血吸虫rSj14-3-3疫苗和rSj26 GST疫苗联合免疫保护作用研究

目的观察日本血吸虫重组信号蛋白14-3-3(rSj14-3-3)疫苗和重组M r2600谷胱甘肽S转移酶(rSj26GST)疫苗联合免疫对小鼠的保护作用。方法将含有Sj14-3-3和Sj26GST编码基因的菌株E.coliBL21/p ET28a涂布LB/Kana/IPTG/X-gal平板,培养、收集细菌、超声碎菌、分离、纯化,分别取5μL进行SDS-PAGE,观察纯化结果,采用BCA法测定重组蛋白的浓度。联合免疫组BALB/c小鼠分别在第0、2、4周用rSj14-3-3疫苗rSj26GST疫苗联合免疫;而单独免疫的rSj14-3-3组及rSj26GST组,与上组同步各自免疫3次。末次免疫后2周进行感染攻击,45d后剖杀,计数成虫及肝内虫卵。同时设PBS对照组。计算各组间的减虫率和减卵率,以及虫卵肉芽肿的大小。结果联合免疫组的减虫率为38.38%,显著高于rSj14-3-3(16.98%)和rSj26GST组(26.80%)(P0.01)。联合免疫组以及rSj14-3-3、rSj26GST组减卵率分别为48.81%、25.27%、41.41%;联合免疫组rSj14-3-3和rSj26GST组,肝组织中每条雌虫平均产卵数显著低于PBS对照组(P0.01)。联合组小鼠虫卵肉芽肿的直径为(173.9±35.0μm),显著小于对照组(267.7±28.6μm)(P0.01),联合组亦明显低于rSj14-3-3和rSj26GST组(P0.01)。结论联合免疫组的保护作用优于rSj14-3-3和rSj26GST单独免疫组。且联合免疫疫苗具有一定的抗虫卵肉芽肿及抗肝纤维化作用。

Protective efficacy of co-immunization with rSj14-3-3 and rSj26 GST vaccines against Schistosoma japonicumin mice

To study the protective efficacy of co-immunization with recombinant Sj14-3-3（rSj14-3-3） and recombinant Sj26 protein（rSj26GST） vaccines against Schistosoma japonicumin BALB/c mice,the LB/Kana/IPTG/X-gal plate was coated by E.coli BL21/pET28a strains which contained rSj14-3-3 and rSj26GST coding genes.The bacteria were then cultured,collected,smashed,separated and purified progressively.The results of SDS-PAGE purified proteins were observed and the concentration of recombinant proteins was determined by BCA.Mice in co-immunization group were co-immunized with rSj14-3-3 and rSj26GST vaccines at week 0,week 2 and week 4.While mice in rSj14-3-3 group and rSj26GST group were respectively immunized with rSj14-3-3 and rSj26GST vaccines in synchrony with co-immunization group.Two weeks after last immunization,mice were challenged by 30±2 cercariae of S.japonicum（Chinese strain）.On day 45 post-infection,mice were sacrificed and the number of worms and eggs in liver tissue was counted.The PBS control group was set and the worm reduction rate and egg reduction rate were counted.Results revealed that the worm reduction rate in co-immunized group was 38.4%,significantly higher than that in rSj14-3-3 group（17.0%,P 0.05） and rSj26GST group（26.8%,P 0.05）.Liver egg reduction rate in co-immunized group,rSj14-3-3 group and rSj26GST group were 48.8%,25.3% and 41.4%,respectively.The average number of oviposition for female in liver of co-immunized mice was significantly lower than that in the control group（P0.01）.The mean hepatic egg granuloma diameter of co-immunized group（173.9±35.0μm） was significantly smaller than that of control group（267.7±28.6μm）（P0.01）.In addition,the diameter of co-immunized group was also smaller than that of rSj14-3-3 group（240.8±44.3μm） and rSj26 GST group（191.6±26.3μm）（P0.05）.It＇s supposed that compared with the immunization of rSj14-3-3 or rSj26GST alone,the co-immunization with rSj14-3-3 and Sj26GST could enhance protective efficacy in BALB/c mice.Furthermore,co-immunized vaccine might act as an effective inhibitor against formation of egg granuloma and reduce immunopathological damage caused by Schistosoma japonicum in the host.