IMMUNE RESPONSE OF FOOT AND MOUTH DISEASE VIRUS TYPE A87/IRN INACTIVATED VACCINE BY GAMMA IRRADIATION ON GUINEA PIG IN IRAN

Document Type: Regular Paper

Authors

1 1Agricultural, Medical and Industrial Research School, Nuclear Science & Technology Research Institute (NSTRI), Karaj, I. R. of Iran, P. O. Box: 31485-498

2 Vaccine and Serum Research Razi Institute, Karaj, I. R. of Iran

3 Agricultural, Medical and Industrial Research School, Nuclear Science & Technology Research Institute (NSTRI), Karaj, I. R. of Iran, P. O. Box: 31485-498

Abstract

Foot and Mouth Disease (FMD) is the most contagious disease of cloven-hoofed animals, causing
significant economical losses in livestock animals. In this study FMD Virus type A87/IRN was cultured and
multiplied on BHK21 cells. The FMD virus was titrated by the Tissue Culture Infection Dose50 method
(TCID50 /ml), the virus titration was 107.5.. The FMD virus samples were irradiated and inactivated by gamma
ray from a 60Co source at -20 °C. A safety test was done by the IBRS2 monolayer cell culture method, also
antigenicity of irradiated and un-irradiated virus samples was studied by Complement Fixation Test. The
Dose/Survival curve for irradiated FMDV was drawn. According to the curve and D10 Value factor, the
optimum dose range for the inactivation of FMDV type A87/IRN and unaltered antigenicity was obtained
(40-44 kGy). The inactivated virus samples by irradiation and ethyleneimine (EI) were formulated
respectively as a vaccine with Al (OH) 3 gel and other substances. The vaccines were inoculated to Guinea
pigs and the results of the Sero-Neutralization Test for both the normal vaccine and radio-vaccine showed
protective titre after 8 months. The potency test of the inactivated vaccines was done, Protective Dose50 Value (PD50 Value) of the vaccines were calculated to be 7.06 and 5.6 for the inactivated vaccine by EI and gamma irradiation respectively.

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