滑液支原体灭活疫苗体外诱导T淋巴细胞增殖及免疫保护研究

Immune protection and proliferation of T lymphocytes in vitro induced by Mycoplasma synoviae inactivated vaccine

滑液支原体感染是由滑液支原体(Mycoplasma synoviae,MS)引起的鸡和火鸡的一种急性或慢性传染病。为控制滑液支原体感染,本研究利用MS WVU1853株辅以Montanide ISA 206 VG佐剂制备了灭活疫苗,研究发现MS灭活疫苗在体外能够激活鸡骨髓来源的树突状细胞(dendritic cell,DCs),DCs能够摄取MS灭活疫苗抗原提呈给T淋巴细胞并刺激T细胞增殖,利用流式细胞术方法检测增殖的T淋巴细胞亚群,CD4+T细胞增殖比率高于CD8+T细胞。SPF鸡免疫高剂量(1010cfu·m L-1)MS灭活疫苗后IFN-γ表达量显著高于对照组(P<0.05),CD4+T细胞主要向Th1类细胞分化并分泌IFN-γ促进CTL细胞发挥杀伤作用,证明灭活MS疫苗能够有效激发免疫鸡群的细胞免疫反应。利用MS灭活疫苗免疫7日龄SPF鸡,单次免疫可以对MS攻毒产生完全保护,另外对疫苗安全性进行检验显示疫苗安全性良好,对鸡安全有效。

Mycoplasma synoviae（ MS） infection disease is an acute or chronic disease of chickens and turkeys which is caused by Mycoplasma synoviae. To control the Mycoplasma synoviae infection,in this study,MS WVU1853 strain with Montanide ISA 206 VG adjuvant were used to prepare inactivated vaccine. Inactivated MS vaccine could activate the chicken bone marrow derived dendritic cells（ DCs） in vitro,DCs can uptake inactivated MS vaccine and present antigen to T lymphocytes and promote the proliferation of T lymphocytes,flow cytometry method was used to detect the subsets of proliferous T lymphocytes,the proliferation ratio of CD4＋T cells were higher than that of CD8＋T cells. SPF chickens treated with high dose of inactivated MS vaccine（ 1010CFU·m L- 1） induced significantly higherimpression of IFN-γ than the control group（ P 〈 0. 05）. CD4＋T cells mainly differentiated into Th1 type cells and released IFN-γ to promote CTL cells playing a role in killing. All of these proved that inactivated MS vaccine could induce cellular immune response effectively in immunized chickens. 7-day-old chickens were treated with inactivated MS vaccine,single immunization could produce complete protection of the attack with Mycoplasma synoviae. The safety test of the vaccine showed that the vaccine was safe and effective for chickens.