Development of an indirect ELISA diagnostic method with the main antigentic region of PCV2 capsid protein expressed in E.coli

An indirect enzyme-linked immunosorbent assay(ELISA) was developed based on a recombinant capsid protein of porcine circovirus type 2(PCV2).The recombinant capsid protein was expressed under the optimum induced condition,purified by a His Bind Purification Kit,and confirmed by Western blot assay.The indirect ELISA was used to test against 380 serum samples collected from Guangdong and Guangxi province and 86.1 % samples were positive.Compared with commercial ELISA kits,the assay showed a correlation rate of 95.6 % based on the data obtained from 90 randomly picked serum samples.The results indicated that the indirect ELISA is not only sensitive and specific,but also suitable for large-scale epidemiological investigation for PCV2 infection.