重组轮状病毒抗原表位亚单位疫苗的小鼠保护性

目的评价重组表达的轮状病毒(RV)抗原表位疫苗的小鼠体内保护效果及安全性.方法在以FlockHouse virus病毒外壳蛋白为载体的外源抗原表位呈递系统(FHV-RNA2系统)中构建和重组表达RV Vp4蛋白上第223～262位抗原表位(REABC);在原核系统[质粒pET,大肠杆菌BL21(DE3)]中表达的REABC免疫小鼠用细胞培养适应的参照RV Wa(G1PA型)和SA11(G3P2型)经口腔灌胃攻击,对RV攻击后的免疫小鼠和对照小鼠的感染症状、排毒情况、血清抗体中和病毒感染性效价进行测定和分析.结果REABC可诱导免疫小鼠产生较强的抗-Wa和抗-SA11株血清中和抗体和特异的免疫记忆反应,有效保护免疫小鼠对Wa和SA11的攻击(不腹泻),减少病毒在体内复制水平和排毒时间,与对照组相比差异具有显著性(P＜0.001).结论重组表达RV抗原表位REABC对小鼠具有较好的免疫保护效果和安全性.

Protective efficacy of recombinant rotavirus epitope-based vaccine in mice

OBJECTIVE: To evaluate in vivo immunological protective efficacy and safety of expressed recombinant rotavirus epitopes in mice. METHODS: Using the Flock House virus capsid protein as a vector, three epitopes derived from rotavirus Vp4 amino acid 223-242 [rotavirus epitope A, (REA)], 243-262 [rotavirus epitope B, (REB)], and 234-251 [rotavirus epitope C, (REC)] were genetically engineered on the surface of the vector protein and expressed in pET-3 (E. coli BL21 [DE3]) system into multiple epitopes, REABC, which comprises REA, REB, and REC. Kunming strain mice were inoculated with the recombinant epitopes REABC, and then challenged perorally by cell culture-adapted rotavirus Wa (type G1P1A) and SA11 (type G3P2). Infection syndrome was observed, and virus antigen in stools of mice and serum neutralizing antibody activities were determined and analyzed. RESULTS: The recombinant epitopes REABC significantly induced rotavirus specific neutralyzing antibodies against WA and SA11, reduced virus reproduction, elicitted immune memory in inoculated mice, and protected inoculated mice from challenge by WA or SA11 (P<0.001). CONCLUSION: The recombinant epitopes have high immunological protective efficacy and mild side effects in mice. It may be used as an epitope-based vaccine candidate in human.