Experimental Study On Safety Of The Recombination Protein Vaccine RSjHGPRT, Against Schistosoma Japonicum

Objective To assess preliminarily the safety of the recombinationprotein vaccine rSjHGPRT against Schistosoma japonicum throughobserving the local tolerance in rabbits, the systemic anaphylaxis inguinea pigs, and the acute toxicity in mice post vaccination withrSjHGPRTMethods A large amount of rSjHGPRT was produced byEscherichia coli M15 transduced with plasmid SjHGPRT/pQE30 underIPTG inducuction. The recombination protein was separated and purifiedby using SDS-PAGE, electroelution and dialysis.The macropathologyand micropathology were conducted to observe the local stimulativereaction at the injected sites of rabbits. The standard technical criteriawere employed to evaluate the risk of allergization in guinea pigs. Thebody weight, ALT, AST, Cr, BUN and the blood routine were measuredwith the maximal dosage method to investigate the acute toxicity of therecombination protein in mice.Result1,A large quantity of the purified recombination protein wasobtained and no bacterium was found in the purified product.2,No changes like congestion, hemorrhage and edema were seen atthe injected sites in rabbits at 72 hours after inoculation. There exist slight inflammatory cell infiltrations, but no cell necrosis could be observedhistologically.3,Most guinea pigs had no allergic symptoms post inoculation withrSjHGPRT. Only one guinea pig showed mild symptoms ofhypersensitivity, which disappeared spontaneously in a short time.4,In acute toxicity test, there were no toxic symptoms occurredduring the experimental period in mice. The liver function, kidneyfunction and blood routine examination of mice were normal. The bodyweight of the experimental animals even increased.Conclusion1,The rSjHGPRT was expressed, separated and purifiedsuccessfully.2,The rabbits inoculated with rSjHGPRT showed no obvious localreactions and histopathological changes.3,The rSjHGPRT hardly gave rise to allergization to the vaccinatedindividuals. Occasional minor hypersensitive symptoms could resolvedspontaneously.4,The acute toxicity test of rSjHGPRT did not show conspicuoustoxicity in mice. The results indicated that the rSjHGPRT is safe in thisstudy.