The present invention entitled "Development of Peste des Petits Ruminants (PPR) negative marker vaccine candidate using a virus neutralizing monoclonal antibody" deals with the development of a monoclonal antibody resistant mutant of PPR Sungri/96 vaccine virus strain (PPRV-Parent) using a virus neutralizing monoclonal antibody 4B11. This mutant was named as " PPRV-Sungri/96/4Bll mutant" in short "PPRV-Mutant". The mutant was isolated after a serial ^ passage of vaccine virus in the presence of an increasing concentration of monoclonal antibody 4B11.The isolated mutant (PPRV-Mutant) was characterized using different binding assays (indirect- ELISA, indirect fluorescent test and indirect fluocytometry), virus fitness test (growth kinetics and thermo-stability) and haemaglutinin gene sequence analysis. Finding indicated that the PPRV-mutant is nonreactive to 4B11 monoclonal antibody and fit for large scale propagation. The "H" gene sequence result showed that PPR mutant virus contained a missense point mutation (T in PPRV parent to C in PPRV Muatnt) at nucleotide position 788th of ORF of H-gene. This resulted in a predicted Leucin-to-Proline change at residue 263 of haemagglutin amio acid sequence (probable epitope site for mAb 4B11). The generated mutant could be an important candidate as a negative marker vaccine for DIVA strategy in association with the currently A used competitive-ELISA kit for PPR antibody detection using the same mAb.
展开▼
