分枝杆菌重组疫苗rBCG-Sj26 GST对小鼠的保护作用

The protective function of recombinant BCG bearing Schistosoma japonicum 26kU antigen gene on mice

为了研究分枝杆菌重组疫苗rBCG Sj26GST对小鼠的保护作用,用分枝杆菌重组疫苗rBCG Sj26GST免疫雄性BALB/c,结核杆菌H37Ra进行攻击,检测小鼠淋巴细胞刺激指数(SI),腹腔巨噬细胞培养上清释放NO量,小鼠血清IFN γ、IL 2的含量,并计数小鼠肝、肺活细菌数.rBCG Sj26GST疫苗免疫的小鼠,其脾淋巴细胞刺激指数(SI)为4.12±1.11,与对照组(2.63±0.47)、载体组(1.06±0.08)和BCG组(1.50±0.41)相比,差异具有显著意义(P<0.05);rBCG Sj26GST组巨噬细胞释放的NO量明显高于对照组(P<0.05).小鼠血清IFN γ的浓度较对照组高33%,但差异无显著意义(P>0.05);与载体组相比,差异具有显著意义(P<0.05).血清白介素 2的浓度较对照组高43%,较载体组高38%,但差异无显著意义(P>0.05).经rBCG Sj26GST免疫的小鼠受结核杆菌攻击后其肺、肝脏结核菌数较对照组少.分枝杆菌重组疫苗rBCG Sj26GST免疫小鼠后能提高小鼠淋巴细胞刺激指数,刺激IFN γ、IL 2的分泌,说明此疫苗能诱导CD+4Th1和CD+8CTL的细胞免疫反应,增强小鼠细胞免疫功能,并使小鼠能抵抗结核杆菌的攻击.

To study the protective function of recombinant BCG bearing Schistosoma japonicum 26*!kU antigen gene.BALB/c male mice were immunized with Mycobacterium recombinant vaccine (rBCGSj26GST).The mice were subsequently challenged with M.tuberculosis H37Ra for eight weeks.Stimulating index(SI)of the evaluated splenic lymphocyte transformation and the amounts of NO in supernatant released form the intraperitoneal macrophages cultured were detected in the mice.The levels of IFNγ and IL2 in the serum were detected.Bacterial CFU in livers and lungs were calculated.The SI of the experimental group was 4.12±1.11,which was significantly higher than those in the control group (2.63±0.47,P<0.05),vector group (1.06±0.08,P<0.05) and BCG group (1.50±0.41,P<0.05).The amouts of NO in supernatant released from the intraperitoneal macrophages of the mice were higher than in the control group(P<0.05).The serum IFNγ level of the experimental group was significantly higher than those in the vector group(P<0.05).Compared with the control group,the serum IFNγ level increased by 33*!%,but there was no statistical difference(P>0.05).The serum IL2 level of the experiemental group was increased by 43*!% and 38*!% compared with the control group and the vector group,but there was no statistical difference(P>0.05).Live bacterial CFU of livers were lower than those in the control group.The splenic lymphocyte proliferating activity in the mice immunized with Mycobacterium recombinant vaccine(rBCGSj26GST) was increased as compared with that in the control group.The vaccine could effectively stimulate host cells to generate IL2 and IFNγ.The results showed that the vaccine could elicit antigenspecific CD+8 CTL and CD+4 Th1 responses and induce extremely strong protective immunity against subsequent challenge with M.tuberculosis H37Ra.