Detection of TGEV Antibody by Enzyme-Linked Immunosorbent Assay Using Recombinant Nucleocapsid Proteins

摘要

An enzyme linked immunosorbent assays (ELISA) based on recombinant nucleocapsid (N) protein generated in Escherichia coli was evaluated for its sensitivity and specificity for diagnosis of transmissible gastroenteritis virus (TGEV) infection. The N gene encoding the N protein was cloned and expressed as a fusion protein with His tag protein in E. coli. The recombinant N protein migrated at 42 kDa and reacted with His_6 tag specific monoclonal antibody by immunoblotting. Recombinant N protein ELISA (rnELISA) demonstrated 97.5% specificity among 80 TGEV-free individuals, and 97.3% sensitivity ranging among 110 clinical samples with TGEV. Taken together, these results indicated that nucleocapsid may be a useful antigen for the sera-diagnosis of TGEV and it was also suggested that the ELISA is a highly sensitive and specific test for detecting antibodies against TGEV.