携带HBV包膜大蛋白DNA疫苗的减毒沙门菌在小鼠诱导免疫应答

探索一种简便、有效的乙型肝炎病毒DNA疫苗免疫方法。将编码绿色荧光蛋白的真核表达质粒pEGFPN1转化到减毒鼠伤寒沙门菌SL7207，灌胃饲服BALB/c小鼠，流式细胞术检测出小鼠脾细胞内表达的绿色荧光蛋白；构建编码HBV包膜大蛋白的DNA疫苗pCIS1S2S，分别以SL7207为载体的口服途径或直接肌肉注射途径免疫BALB/c小鼠，检测小鼠的血清抗体、T细胞增殖和细胞毒性T淋巴细胞反应，结果表明两种免疫途径均能在小鼠体内诱生细胞和体液免疫应答，但口服途径诱导免疫应答的强度明显强于肌肉注射途径。口服携带HBV DNA疫苗的减毒伤寒沙门菌可能代表一种简便、有效的治疗乙型肝炎的新方法。 

Induction of Immune Responses in Mice by Hepatitis B Virus Large Envelope DNA Vaccine Delivered by Attenuated Salmonella typhimurium

The enhanced green fluorescent protein (EGFP) expression plasmid was transformed into an attenuated AroA - autotrophic mutant of Salmonella typhimurium SL7207, the resultant bacteria was administered orally to BALB/c mice. EGFP expressed in spleen cells was detected by flow cytometry. A DNA vaccine encoding HBV large envelope protein was immunized BALB/c mice by oral delivery through SL7207 or by direct intramuscular injection. The serum antibodies, T lymphocyte proliferative response and cytotoxic T lymphocyte response of mice were detected. The results showed that both DNA immunization methods could induce cellular and humoral immune responses, whereas oral vaccination elicited stronger immune responses than intramuscular vaccination did. Therefor, oral administration with HBV DNA vaccine using attenuated Salmonella may be a simple and effective method for the therapy of hepatitis B.