结核杆菌ESAT-6基因疫苗对结核杆菌感染小鼠的免疫保护效果研究

Studies on Immunogenicity and Protective Efficacy of Mycobacterium Tuberculosis ESAT-6 Gene Vaccine to Mice Infected by Mycobacterium Tuberculosis

为研究结核杆菌ESAT-6基因疫苗的免疫原性及对小鼠结核杆菌感染的免疫保护效果,将雌性C57BL/6N小鼠32只,随机分为4组,即结核杆菌ESAT-6基因疫苗组、BCG组、pcDNA3.1(+)组和PBS组。取小鼠脾细胞培养上清检测细胞因子水平;并按效靶比例分别为100∶1、50∶1、10∶1进行CTL杀伤活性检测。用结核杆菌H37Rv国际标准强毒株静脉注射攻击小鼠,计数肺和脾组织中的结核杆菌菌落数,对小鼠部分肺和脾组织作病理切片,HE染色观察组织病变程度,Z-N染色检查抗酸杆菌,观察该疫苗对小鼠结核杆菌感染的免疫保护效果。结果表明,结核杆菌ESAT-6基因疫苗对小鼠结核杆菌感染有一定的免疫保护效果,可诱导较强的抗原特异性Th1型细胞免疫应答,细胞因子IFN-γ和IL-1分泌增加,IL-4分泌减少,CTL特异性活性增加;使小鼠肺和脾组织中的结核杆菌菌落数较空载体组显著减少,组织病变明显减轻。

To study the immunogenicity and protective efficacy of Mycobacterium Tuberculosis ESAT-6 gene vaccine to mice infected by Mycobacterium Tuberculosis, 32 C57BL/6N mice were divided into four groups： Mycobacterium Tuberculosis ESAT-6 gene vaccine group, BCG group, pcDNA3. 1 （ ＋ ） group and PBS group. Cell of spleen were harvested from three mice for assessing cytokine response and CTL induction, and the other five mice were challenged in a lateral tail vein with virulent Mycobacterium Tuberculosis H37Rv. Spleen and lung were harvested from each mouse for counting the number of Mycobacterium Tuberculosis loading in Spleen and lung, and making HE coloration of the spleen and lung tissue for observing degree of pathological changes;and making Z-N coloration of the spleen and lung tissue for observing the protective efficacy of Mycobacterium Tuberculosis ESAT-6 gene vaccine to mouse infected by Mycobacterium Tuberculosis. Results show Mycobacterium Tuberculosis ESAT-6 gene vaccine have the higher protective efficacy to mice infected by Mycobacterium Tuberculosis,and could induce stronger Th1 cell immune response, and secrete much IFN-γ cytokines, IL-2 cytokines and secrete lit tler IL-4 cytokines, and could increase CTL special character; and decrease the number of Mycobacterium Tuberculosis loading in Spleen and lung and lighten degree of tissue pathological changes compare with control group.