硫糖铝对幽门螺杆菌VacA IgY的保护作用的动物实验评价

Evaluation on protective effects of sucralfate on H.pylori-VacA-IgY in animal experiments

目的评价硫糖铝在胃内对H.pyloriVacA IgY型抗体的保护作用,为制备H.pyloriVacA IgY型抗体口服剂提供实验依据。方法大量诱导工程菌DH5α-vacA-pQE30,表达并纯化重组蛋白VacA。以VacA为抗原接种洛曼母鸡,制备纯化的IgY。建立H.pylori感染的小鼠模型,在不同浓度的IgY液中分别加入30%硫糖铝,灌胃后观察胃黏膜慢性炎症反应以评价硫糖铝在胃内对VacA IgY的保护作用。结果在小鼠胃内,0.5mg IgY+30%硫糖铝/天灌胃小鼠即可有效防治H.pylori感染引起的胃黏膜损害,与不加硫糖铝比较,其效果提高了8倍。结论 30%以上的硫糖铝在小鼠胃内可增强VacA IgY对低pH和胃蛋白酶的耐受能力,是较理想的抗H.pyloriVacA IgY型抗体保护剂。

Objective To evaluate the protective effects of suczalfate on anti-H, pylori VacA immunoglobulin yolk （VacA IgY） intragastricalIy and provide experimental basis for preparation of oral-administration IgY. Method The recombinant vacuolate cytotoxin antigen（VacA） was expressed in engineering bacteria DHSct-vacA-pQE30 and purified. VacA IgY was prepared by inoculating purified VacA in Lohman hens and then depurated. Mice infected by H. py/or/were intragastrically administered 30% sucralfate and IgY solutions of different concentrations. The chronic inflammstory reaction of gastric mucosa was observed to evaluate the protective effects of sucralfate on VacA IgY in stomach. Result Intragastric administration with 0.5 mg IgY plus 30% sueralfate per day could effectively prevent and cure the injury of gastric mucosa caused by 1t. pylori infection. The protective effect of VacA IgY group containing 30% sucralfate was eight times as that of the groups without sucralfate. Conclusion 30% or higher concentration of sucralfate can enhance the tolerance of VacA IgY to low pH value and pepsin intragastrically and may be an ideal protectant for IgY.