产肠毒素大肠杆菌基因工程疫苗在小鼠中的免疫原性

目的观察肠毒素大肠杆菌(ETEC)基因工程疫苗的抗原性效果,筛选有效的防治ETEC腹泻病基因工程疫苗株。方法将表达ETEC抗原成分的重组质粒pZCF16和pZHY22分别转化入载体痢疾福氏2a菌株FWL01中,构成含不同ETEC抗原成分的工程疫苗株FE3和FE16。分别用FE3与FE16活菌和灭活菌制成的疫苗以同等剂量梯度,通过口服和鼻饲途径免疫小白鼠,经过一定时间检测2组小白鼠的免疫效果。结果在免疫后的小白鼠血液中均产生了特异性抗IgG抗体,在活菌免疫组肠道内也产生了特异性分泌型抗体IgA;抗体IgG 1周后开始升高,且在8周后达到高峰。抗体IgA的产生规律与IgG相似。结论肠毒素大肠杆菌载体菌苗FE3和FE16有较强的免疫原性,作为多价疫苗的构建是有效的,从而为ETEC腹泻的特异性免疫防治提供了可能。

IMMUNOGENICITY OF ENTEROTOXIGENIC ESCHERICHIA COLI GENETIC VACCINE IN MOUSE

Objective To observe the antigenicity of genetic engineering vaccine of enterotoxigenic Escherichia coli(ETEC),so as to screen out the effective strains of it for prevention and cure of ETEC diarrhea.Methods Select the recombinant plasmids pZCF16,pZHY22, and transform them separately into the carrier of FWL101,then the engineering vaccine strains with different antigen of FE3,and FE16 were composed.Immune the mice using the vaccine from alive,and dead bacteria of FE3,and FE16 respectively in coequal dosage grade both by taking orally,and by feeding through nose,detect the immune effect in given times.Results Serum specific anti-IgG antibody could be detected in the blood of all the immune mice.Secreted antibody IgA in the intestine in alive bacteria immunized groups could be found too.IgG antibody began to rise after one week and reach peak value after 8 weeks.The generation pattern of IgA was similar to that of IgG.Conclusion FE3,and FE16 have relatively strong immunogenicity,and the multivalent vaccine constructed from them is effective,thus it provides the possibility for the prevention and cure of specific immunity of ETEC diarrhea.