¹College of Animal Science and Veterinary Medicine, Henan Institute of Science and Technology, Xinxiang 453003, CHINA
²Medical Research Center, Xinxiang Medical College, Xinxiang 453003, CHINA
³Key Laboratory of Animal Immunology of the Ministry of Agriculture, Henan Provincial Key Laboratory of Animal Immunology, Henan Academy of Agricultural Sciences, Zhengzhou, 450002, CHINA DOI : 10.9775/kvfd.2018.19776 Porcine epidemic diarrhea virus (PEDV) is a devastating swine infectious disease. Development of high-performance methods to diagnose and evaluate viral immune status remains very important to control PEDV. Here, a recombinant S1 protein-based indirect enzyme-linked immunosorbent assay (rpS1-iELISA) was developed to monitor IgA antibody in the colostrum. Optimized cut-off value of the rpS1-iELISA was determined as 0.448. Results yielded a sensitivity of 96.87% and a specificity of 100.0%. Repeatability tests indicated that the coefficients of variation of the colostrum samples within and between runs were both less than 8%. Test results of 523 field colostrum samples showed that the rpS1-iELISA had excellent agreement with immunofluorescence assay (kappa = 0.958) and better test performance than a commercial ELISA kit. This test will aid in future diagnostics and assessment of the protective levels of mucosal immune response against PEDV by measuring IgA levels in the colostrum. Keywords : ELISA, IgA antibody, Colostrum, Porcine epidemic diarrhea virus, Spike protein