rAAV2-BF增强两品系小鼠抗致死剂量细菌感染

 目的 通过观测rAAV2-BPI1-199-Fc 1重组病毒（rAAV-BF）感染对不同品系小鼠的抗细菌感染保护作用。方法 采用Dot-blot、Western blot、免疫组化、改良ELISA方法和内毒素检测试剂盒，检测重组BPI1-199-Fc 1（rBF）蛋白在CHO细胞和小鼠骨骼肌细胞中的表达及血清中内毒素含量的变化；建立最小致死量(MLD)E.coli致死模型,检测rBF基因转染小鼠对MLD E.coli感染的抵抗作用。结果（1）rBF蛋白在CHO细胞和两品系小鼠骨骼肌细胞中成功表达，血清中rBF蛋白具有中和内毒素和杀伤E.coli 的作用；（2）在MLD E.coli腹腔感染后，两品系小鼠rAAV-BF感染组存活率均显著高于空载体对照组小鼠；基因转染组小鼠血清内毒素含量明显低于空载体对照组；rAAV-BF感染与头孢呋辛钠联合应用具有协同抗菌作用，两品系小鼠存活率明显高于单纯rAAV-BF感染组。结论rAAV-BF感染组小鼠对致死性E.coli感染具有抵抗作用。

The protective effect of rAAV2-BF for different strains of mice from lethal bacteria infection

Objective The purpose of this study is to observe the protective effect of rAAV-BF infected mice against lethal dose of E.coli.Methods The rBF protein in CHO cells、mice injected muscle and serum were detected by Dot-blot、Western blot、immunohistochemistry assay and a modified enzyme linked immunosorbent assay(ELISA),the levels of endotoxin were measured by reagent kits,establishing MLD E.coli causing death model for the detection of the mice resistant to MLD E.coli infection after administration with rAAV-BF.Results (1)The presence of rBF protein was detected in CHO cells and injected mice muscle, serum from the gene transfected mice could neutralize endotoxin and kills E.coli.(2)The survival rate of Balb/c and C57BL/6 mice of rAAV group（30%-40%）was significantly higher than control group（0%）.Serum endotoxin level of rAAV-BF group mice was significantly lower than that control group. rAAV-BF plus antibiotics have synergistic effect：the survival rate of rAAV-BF group was significantly higher than that of control group; the survival rate（85%） of rAAV-BF infected C57BL/6 mice was significantly higher than that of Balb/c mice（65%）.Conclusion rAAV-BF infected mice have restistence to lethal dose of E.coli, which might provide the base to protect clinical high risk patients from being infected by bacteria and accordingly to reduce mortality.