多房棘球绦虫重组BCG-EmⅡ/3疫苗诱导小鼠脾细胞凋亡的研究

Study on apoptosis of splenocytes in mice immunized with recombinant BCG-EmⅡ/3 vaccine against Echinococcus multilocularis

目的探讨多房棘球绦虫(Em)重组卡介苗(BCG-EmⅡ/3)疫苗免疫对Em原头节攻击小鼠脾细胞凋亡的影响。方法Balb/c小鼠随机分为疫苗皮下注射组、鼻腔接种组、空载体对照组、卡介苗(BCG)对照组和PBS对照组。免疫8周时用Em原头节攻击感染,感染后18周剖杀小鼠,计算减蚴率;取脾分离脾细胞,流式细胞仪检测脾细胞的凋亡发生率。结果与PBS对照组相比,疫苗皮下注射组和鼻腔内接种组小鼠检获泡球蚴质量均降低(q=2.65、3.68,P<0.05或P<0.01),疫苗鼻腔内接种组与皮下注射组比较,检获泡球蚴质量明显降低(q=2.78,P<0.05),疫苗接种组的减蚴率为63.23%～74.70%;疫苗接种组的脾细胞凋亡发生率明显低于PBS对照组(P<0.01);皮下注射组的脾细胞凋亡发生率明显低于鼻腔内接种组(P<0.01)。结论泡球蚴感染可引起小鼠脾细胞发生凋亡。多房棘球绦虫重组BCG-EmⅡ/3疫苗接种可抑制感染鼠脾细胞凋亡。

Objective To investigate apoptosis of splenocytes in mice immunizd with recombinant BCG- Em Ⅱ/3 vaccine of Echinococcus multilocularis （Em） and against challenge with Em protoscoleces. Methods Balb/c mice were subcutaneously and intranasally immunized by the vaccine respectively, then were challenged with Em protoscoleces on 8^th of vaccination and killed on 18^th of infection to count rate of reduced alveolar echinococcus weight. The spleen was taken to separate splenocytes, their apoptotic rate were measured by flowcytometry. Blank vector, BCG and PBS served as control. Results The rate of reduced alveolar echinococcus weight was 63.23% ~ 74.70% in the groups of immunization. The apoptotic rate in the immunization group was lower than that in the infection controls, that in subcutaneous group was lower than that in the intranasal group. Conclusions Apoptosis of splenocytes in mice may be induced by the infection of alveolar hydatid cyst,which can be inhibited by immunization with recombinant BCG-Em Ⅱ/3 vaccine of Echinococcus multilocularis.