FULL-LENGTH INFECTIOUS CDNA CLONE FOR INDIAN VACCINE STRAIN OF FOOT-AND- MOUTH DISEASE VIRUS SEROTYPE O (IND-R2/75)

摘要

Foot-and-mouth disease virus (FMDV) serotype 0 is the most predominant serotype causing FMD outbreaks in India. FMDV is the prototype member of the genus Aphthovirus. This invention relates to the construction of an infectious cDNA clone of the Indian vaccine strain of FMDV serotype 0, IND-R2/75 strain (sequence provided in Table 2) employing murine RNA polymerise I (murine RNAPI) in vivo transcription system. Transfection of BHK-21 cells with the plasmid containing full genome length cDNA resulted in the production of infectious FMDV particles as evidenced by cytopathic effects (CPE) in the cultured cells. Further, characterization of the recombinant virus was done by virus neutralization test (VNT), antigen ELISA, plaque assay. The virus derived from the infectious clone was remarkably similar to the parental strain. In order to distinguish parental virus from the rescued virus derived from the infectious cDNA, a signature sequence is included in the latter as a genetic marker. The methodology described in this paper could be an extremely helpful molecular tool for studying complex infectious and genetic characteristics of the virus. This can be used for studying FMDV genomics, genetic variations, molecular mechanism of pathogenicity, virulent genes and could serve as a valuable tool for the development of genetically engineered virus towards the production of more potent and effective vaccines.