弓形虫P30乳酸球菌口服疫苗诱导小鼠的体液免疫反应及保护性观察

目的观察弓形虫P30乳酸球菌口服疫苗在小鼠体内诱导的体液免疫反应,以及产生的保护性效果. 方法P30乳酸球菌口服免疫BALB/c小鼠,以gp42乳酸球菌组和生理盐水组为对照,4周内免疫7次,免疫结束后,分别收集各组小鼠血清,ELISA法检测血清中总抗体IgG和抗体亚类IgG1和IgG2a水平,同时用100个弓形虫RH株速殖子攻击各实验小鼠. 结果 P30乳酸球菌口服免疫小鼠组检测到了相应的抗体,抗体亚类IgG2a的生成量稍高于IgG1,两对照组均检测不到明显的相应抗体;攻击后,口服疫苗免疫组平均存活时间多于对照组4 d. 结论 P30乳酸球菌口服疫苗刺激小鼠产生了相应的抗体,诱导产生了偏向Th1型的免疫反应,且在小鼠体内发挥了部分保护作用.

HUMORAL IMMUNE RESPONSE AND PROTECTIVE EFFECT IN MICE INDUCED BY ORAL VACCINATION OF RECOMBINANT LACTOCOCCUS LACTIS EXPRESSING P30 OF TOXOPLASMA GONDII

Objective To observe the humoral immune response and protective effect of against challenge in mice immunized with oral vaccination of recombinant Lactococcus lactis expressing P30 of Toxoplasma gondii . Methods Recombinant L. lactis -P30 was administered orally to BALB/c mice. Control groups were administered orally with gp42 L. lactis and normal saline respectively. After 7 interval within 4 weeks,sera from all animals were tested by ELISA for the presence of total antibodies IgG and the IgG1 and IgG2a antibody isotypes,and then each mouse was challenged with 100 tachyzoites of the RH strain of T. gondii . Results Specific antibodies IgG and IgG isotypes were found in mice orally vaccinated with recombinant L. lactis -P30,the levels of IgG2a exhibited slightly higher than that of IgG1,whereas no specific antibodies and isotypes were detected in two control groups;Increased four survival days against lethal RH strain challenge were obtained in mice immunized with oral vaccination of L. lactis -P30 compared with two control groups. Conclusion Oral vaccination of L. lactis -P30 generated specific antibodies against the recombinant P30 in mice,a Th1-type response had been induced,and a partially protective effect against T. gondii was obtained.