ABSTRACT
Objective To prepare the bivalent immunoglobulin yolk (lgY) against eobra and viper venom and to detect its activities as the foundation for production and application of polyvalent . Methods The venom of Naja atra Cantor and Daboia russellii siamensis injected alternately into the leghorn hen. Biva-lent lgY was extraeted by water dilution. The biological activity of bivalent lgY were deteeted in several as-pects, sueh as the potency ( by indireet ELISA assay), the cross immunity ( by double immunodiffusion), the membrane lysis activity ( by experiments of vitelline membrane lysis) and 50% lethal activity ( LD50 ). Results Bivalent IgY was extracted from eggs yolk in 28-42 days after the first immunization. The titers of bivalent lgY against cobra and viper venom were 1:12 800 and 1: 6400. The cross immunologic reactions of bivalent IgY were found obviously with six kinds of snake venoms from Elapinae and Viperinae. There were not immunologic precipitation lines between bivalent IgY and four kinds of snake venoms from Crotalinae. Bi- valent lgY obviously deereased the vitelline membrane lysis activity of cobra and viper venom and prolonged the average survival time of mice with cobra or viper envenomation (P < 0.05). Moreover, with the same dose of bivalent IgY, the survival rate of mice with cobra venom envenomation was higher than those with vi-per venom envenomation. Conclusion Bivalent lgY could signifieantly neutralize biologieal activities of co-bra and viper venom, protect animals with cobra or viper envenomation.
ABSTRACT
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