Development of recombinant VP2 vaccine for the prevention of infectious bursal disease of chickens. Rong Jun,Cheng Taipin,Liu Xiaona,Jiang Taozhen,Gu Hong,Zou Guolin Vaccine The objective of the present study was to investigate the feasibility of a subunit vaccine and a live bacteria vaccine to protect chickens against infectious bursal disease virus (IBDV) infection. The gene for VP2 of a new wild-type very virulent IBDV (vvIBDV) strain was cloned into an Escherichia coli expression system. Following expression, the recombinant VP2 and the induced expression bacteria were used to vaccinate chickens against virulent IBDV (vIBDV). Three weeks after the vaccination, chickens were inoculated with IBDV strain BC 6/85 by intranasal route or eyedrop route, prior to challenge anti-IBDV serum antibody was detected by AGP. All chickens vaccinated with recombinant VP2 could be detected anti-IBDV antibody. The subunit vaccine of recombinant VP2 conferred protection for 90--100% chickens, live bacteria vaccine of recombinant VP2 conferred protection for 85.7% chickens. The results indicate that E. coli BL 21/pET 28 a-VP2 could be used to develop recombinant VP2 vaccine against infectious bursal disease in chickens. 10.1016/j.vaccine.2005.05.015

Development of a recombinant VP2 vaccine for the prevention of novel variant strains of infectious bursal disease virus. Li Guopan,Kuang Hongyan,Guo Huaxiong,Cai Lianshen,Chu Dianfeng,Wang Xi,Hu Jixiong,Rong Jun Avian pathology : journal of the W.V.P.A Since 2017, novel variant strains of infectious bursal disease virus (nvIBDV) have been detected in China, while the current vaccines on the market against very virulent IBDV have limited protection against this subtype virus. In this context, a strain of the virus has been isolated, and sequencing alignment and bird regression experiments showed that the virus was IBDV, belonging to the nvIBDV subtype (and named IBDV FJ-1812). Furthermore, the expression system was used to successfully express soluble nvIBDV rVP2, which is specifically recognized by an anti-IBDV standard serum and anti-nvIBDV positive serum, and could be assembled into 14 - 17 nm virus-like particles. Based on the purified nvIBDV rVP2, we developed an IBDV FJ-1812 VP2 VLP vaccine at a laboratory scale to evaluate protection by this vaccine; in addition, we also prepared an IBDV JZ 3/02 VP2 subunit vaccine targeting very virulent IBDV and evaluated its cross-protection against nvIBDV. Results of bird experiments showed that the nvIBDV rVP2 vaccine could induce high titres of specific antibodies, completely protect the bursa of Fabricius from viral infection, and provide 100% immune protection to SPF and Ross 308 broiler chickens. Furthermore, the IBDV JZ 3/02 VP2 subunit vaccine targeting very virulent IBDV could provide 60% protection for SPF chickens and 80% protection for Ross 308 broiler chickens. This report provides important technical supports for the prevention and control of nvIBDV in the future. 10.1080/03079457.2020.1791314