双价抗蛇毒IgY灌胃对眼镜蛇、蝰蛇伤小鼠的保护作用

目的： 比较双价抗蛇毒鸡卵黄抗体(IgY) 经腹腔注射或灌胃对蝰蛇、眼镜蛇伤小鼠保护作用的差异，为其口服制剂的应用奠定理论基础。方法：2种单一抗原按顺序依次交替注入单只鸡体内，水稀释法制备双价抗蛇毒IgY；间接ELISA法观察双价抗蛇毒IgY在体外及其灌胃后小鼠血浆中的效价，通过胃排空试验确定灌胃给药的最佳时间，在此基础上，比较双价抗蛇毒IgY腹腔注射或灌胃对蛇伤小鼠的保护作用。结果：初次免疫后28 d至第42 d，以水稀释法提取的双价抗蛇毒IgY对眼镜蛇毒及蝰蛇毒的效价分别为1∶12 800和1∶6 400。不同浓度的双价抗蛇毒IgY灌胃2.5-3.5 h，小鼠的胃排空率均达68.9％以上，血浆中抗体浓度亦相应达高峰。该抗体腹腔注射或提前灌胃均能极显著延长眼镜蛇和蝰蛇毒中毒小鼠的存活时间（P<0.01），同等剂量的双价抗蛇毒IgY提高眼镜蛇伤小鼠存活率优于蝰蛇伤，而灌胃有效剂量约为腹腔注射的10倍。结论：双价抗蛇毒IgY经2种给药途径（注射、口服）均能有效保护动物免受眼镜蛇毒和蝰蛇毒的攻击。

Protective effect of bivalent anti-snake venom IgY administered intragastrically on mice with cobra or viper envenomation

AIM: The different effect of bivalent immunoglobulin Yolk (IgY) was evaluated against snake venom between intragastric administration and intraperitoneal injection in mice with cobra or viper envenomation. METHODS: The venom of naja and viper was injected alternately into the leghorn hen. Bivalent anti-snake venom IgY was extracted by water dilution. The concentration of bivalent IgY in plasma was observed in indirect ELISA assay after bivalent anti-snake venom IgY taken orally. The gastric emptying function test was used for determining optimization time after gastric administration of IgY. The protective effect of bivalent anti-snake venom IgY was compared between intragastric administration and intraperitoneal injection in mice with cobra or viper envenomation. RESULTS: Bivalent anti-snake venom IgY was extracted from eggs laid in 28-42 d after the first immunization. The titers of Bivalent IgY against cobra and viper venom were 1∶12 800 and 1∶6 400. At the time of 2.5-3.5 h after bivalent anti-snake venom IgY was taken orally in three concentrations (75 mg, 150 mg, 300 mg·0.5 mL-1·20 g-1 BW), the gastric evacuation rate of mice was above 68.9%, with the plasma concentration of bivalent IgY in peak. The survival time of mice envenomation with snake venom was extremely prolonged (P<0.01), after IgY was taken by intragastric administration or intraperitoneal injection. While administration with the same dose of IgY, the survival rate of mice envenomation with cobra venom was higher than that of viper venom. The effective dose of intragastric administration was decuple higher than that of intraperitoneal injection. CONCLUSION: The animal envenomation with cobra or viper venoms can be significantly protected by bivalent anti-snake venom IgY with intragastric administration or intraperitoneal injection.