Expression and immunogenicity analysis of VP2 protein of a Chinese infectious pancreatic necrosis virus from diseased rainbow trout Oncorhynchus mykiss
ZHAO Jing-zhuang1, HE Wen-bin1, XU Li-ming1, JI Feng1, CAO Yong-sheng1, HU Chao2, LU Tong-yan1
1.Heilongjiang River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Harbin 150070,China; 2.Dujiangyan Administration of Sichuan Province, Dujiangyan 611830, China
Abstract: An IPNV isolate obtained by epidemiological investigation from rainbow trout Oncorhynchusmykiss was analyzed in the evolution and transmembrane region, hydrophilicity, antigenicity and surface possibility of the VP2 protein in IPNV isolate by a software to understand the phylogenetic evolution of the Chinese infectious pancreatic necrosis virus and provide a theoretical basis for the virus detection and vaccine construction of the disease. Prokaryotic expression of the specific regions was carried out using pET-27b-VP2 vector and mouse antiserum was prepared with the expressed proteins. It was found that IPNV isolate was derived from different sources compared with the other isolates reported in China. SDS-PAGE revealed that the VP2 protein expressed and purified had a single band with relative molecular weight of approximate 45 000. ELISA analysis showed that the antisera against VP2 protein prepared here reacted specifically with both the recombinant VP2 protein and IPNV, with the maximal titer against recombinant VP2 protein of 1∶40 000, and the IPNV of 1∶20 000. Indirect immunofluorescence analysis (IFA) indicated that the antisera recognized IPNV in infected cells exposed for 24 h and 48 h via specific green fluorescence. The findings indicated that the antigenicity of recombinant VP2 protein was similar as that of IPNV, which provided important research basis for the detection and vaccine preparation of IHNV.
2019, Vol. 34 
