重组鸡白细胞介素-6/2融合蛋白对新城疫(LaSota株)活疫苗免疫增强作用研究

Immunopotentiation Effect of Recombinant Chicken Interleukin-6/2 Fusion Protein on Newcastle Disease Virus (LaSota) Live Vaccine

为探究重组鸡白细胞介素-6/2融合蛋白(rChIL-6-Linker-ChIL-2,重组融合蛋白)对新城疫病毒(NDV)活疫苗(LaSota株)的免疫增强作用,本研究将90只SPF鸡随机分为6组,分别为PBS对照组、NDV弱毒苗对照组、rChIL-6-Linker-ChIL-2免疫增强组、rChIL-6蛋白免疫增强组、rChIL-2蛋白免疫增强组及rChIL-6+rChIL-2混合蛋白免疫增强组,将鸡白细胞介素重组融合蛋白水剂与LaSota株联合接种于SPF鸡,分别采用MTS法、流式细胞术、ELISA和HA/HI法检测接种前后不同时间各组鸡外周血及脾淋巴细胞增殖活性、鸡外周血中CD3+CD4+/CD3+CD8+T淋巴细胞的百分含量、血清中Th1/Th2型细胞因子表达水平及免疫抗体水平等指标。结果显示,接种后7～21d时,与NDV弱毒苗对照组相比,同时接种重组融合蛋白组鸡淋巴细胞增殖活性、外周血CD3+CD4+/CD3+CD8+T淋巴细胞的百分含量比值及血清中重组鸡IL-4蛋白(rChIL-4)、ChIL-6、ChIL-2、重组鸡IFN-α蛋白(ChIFN-α)、ChIFN-γTh1/Th2型细胞因子表达水平明显提升;HI免疫抗体较NDV弱毒苗对照组提高了1.0～1.9个滴度,较单一rChIL-6、rChIL-2对照组分别提高了0.2～0.7、0.2～1.1个抗体滴度。综上所述,rChIL-6-Lin-ker-ChIL-2融合蛋白对NDV(LaSota株)活疫苗在鸡体内具有明显的免疫增强效果。

In order to study the immunopotentiation effect of recombinant chicken interleukin-6/2 fusion protein(rChIL-6-Linker-ChIL-2)on Newcastle disease vinus(NDV)live vaccine(LaSota vaccine),90 SPF chickens were chosen and randomly distributed into six groups which were the PBS control group,NDV live vaccine control group,rChIL-6-Linker-ChIL-2 immunopotentiation group,rChIL-6 protein immunopotentiation group,rChIL-2 protein immunopotentiation group andthe rChIL-6^+rChIL-2 fusion protein immunopotentiation group.The interleukin fusion protein fluid and NDV live vaccine(LaSota vaccine)were inoculated into SPF chickens.The indexes of proliferation activities of peripheral blood and splenic lymphocytes,percentages of the CD3^+CD4^+/CD3^+CD8^+T-lymphocytes in peripheral blood,the contents of Th1/Th2-type cytokines and the specific immune antibody level were detected by assays of MTS,FCM,ELISA and HA/HI.The results showed that compared with the indexes of NDV vaccine inoculation control group,the lymphocytes proliferation activity,the percentage of CD3^+CD4^+/CD3^+CD8^+T-lymphocytes,and the contents of Th1/Th2-type cytokines such as ChIL-4,ChIL-6,ChIL-2,ChIFN-αand ChIFN-γof chickens in rChIL-6-Linker-ChIL-2 inoculation group were promoted obviously at7 to 21 dpi,and the HI immune antibodies increased about 1.0 to 1.9 titer,which was 0.2 to 0.7 titer higher than that of rChIL-6 group and 0.2 to 1.1 titer higher than rChIL-2 that of group.In conclusion,the rChIL-6-Linker-ChIL-2 protein had an obvious immunopotentiation effect on NDV live vaccine(LaSota)in chickens.