Cloning and secretory expression of VP2 gene of infectious bursal disease virus in eukaryotic cells

VP2 gene coding region of a vaccinal strain (D78) of infectious bursal disease virus (IBDV) was cloned in a eukaryotic expression vector, pSec Tag2A. The gene was placed downstream of Ig κ chain leader sequence, under the control of human cytomegalovirus (hCMV) immediate early enhancer and promoter. The construct pSec Tag2A-VP2 was transfected in COS-7 cell line and the expression and secretion of VP2 was assessed by dot blotting and antigen capture ELISA. The antibody used in the immunological assays was a neutralizing monoclonal antibody (1A6) against VP2. Positive reaction with the antibody indicated the construct was functional with respect to expression and secretion of a native VP2.