以减毒沙门氏菌为SARS-CoV N DNA口服疫苗载体的初步研究

目的:以减毒沙门氏菌为载体运送SARS-CoV N DNA疫苗至小鼠体内，研究其诱导的免疫应答情况，评价减毒鼠伤寒沙门氏菌作为口服疫苗的免疫效果。方法：将含SARS-CoV N基因的pcDNA-N质粒导入减毒鼠伤寒沙门氏菌CS022中，采用口服和滴鼻相结合的方法免疫BALB/c小鼠，以ELISA检测不同时间免疫小鼠血清中抗体及其亚型；以MTT法测定特异性淋巴细胞增殖反应；ELISPOT检测细胞因子；流式检测T细胞亚型。结果：pcDNA-N DNA疫苗口服免疫后2周就可以诱生特异性IgG抗体，且以IgG2a占优势；诱导了较高水平的淋巴细胞特异性增殖反应和IFN-γ，主要以Th1免疫为主。结论：减毒沙门氏菌可以有效运送pcDNA-N重组质粒并诱导产生特异体液和细胞免疫应答，为减毒细菌作为DNA疫苗运送载体的研究提供了参考依据，也为SARS疫苗研究开辟了新方法。

Live-attenuated Salmonella typhimurium as a Oral Delivery Vehicle for SARS-CoV N DNA Vaccine

Objective:To investigate the immunogenicity of SARS-CoV N DNA vaccine and the feasibility of live-attenuated Salmonella typhimurium as the carrier to deliver the N DNA vaccine.Method:The recombinant attenuated salmonella strain CS022 harboring the pcDNA-N DNA vaccine was constructed.And mouse was immunized with the recombinant strain via intranasal and oral routes.Cellular and humoral immune responses were assessed by ELISA,lymphocyte proliferation assays,ELISPOT and FACS.Result:The oral immunization with t...