Construction and identification of bacteria-like particles surface-displaying Infectious bursal disease virus VP2 protein

In order to construct bacteria-like particies（BLPs） exhibiting Infectious bursal disease virus（IBDV） VP2 protein, in this experiment, VP2 gene and protein anchor（PA） gene fragment of Lactococcus lactis were cloned, respectively. VP2-PA fusion gene was constructed by fusion PCR technology, and recombinant Baculovirus rBV-VP2-PA was constructed by Bac-to-Bac Baculovirus/insect cell expression system. The expression products were incubated with the prepared bare BLPs, and under the mediation of PA, bacteria-like particles（BLPS-VP2） exhibiting IBDV VP2 were constructed. BLPs-VP2 was identified by transmission electron microscopy, SDS-PAGE, Western-blot and indirect immunofluorescence, successively. The results showed that VP2 protein was successfully expressed and showed on the surface of BLPs, and it could bind specifically to IBDV positive serum, and the maximum VP2-PA fusion protein supported by 1 U（2.5×10~9 particles） BLPs was about 107 μg. The results indicated that BLPs of IBDV VP2 protein was available for the research and development of novel subunit vaccine of infectious bursal disease（IBD）.