Cloning, expression and monoclonal antibody of porcine interferon-regulated antiviral gene

Background: IRAV (interferon-regulated antiviral gene) was identified with antiviral activity as a novel interferon-stimulated gene. IRAV is upregulated in response to type I and type II IFNs and a number of virus. However, the antiviral activity of IRAV to virus infection is poorly understood. Results: In this study, we cloned the full-length IRAV complementary DNA (cDNA) from porcine kidney cells. The porcine IRAV cDNA was of 1241 bp with an open reading frame of 858 bp, encoding a polypeptide of 285 amino acids, which localized to the cytoplasm. The porcine IRAV protein was expressed in Escherichia coli BL21 (DE3), purified and immunized to female BALB/c mice to get monoclonal antibodies (MAbs) against porcine IRAV. Five strains of hybridoma cells named 2B10, 2G12, 2H1,5A8 and 2C5 secreting anti-IRAV MAbs were obtained. By western blot analysis and indirect immunofluorescence assay, the MAbs were identified with the specific reaction with the overexpressed porcine IRAV protein in PK15 cells. Conclusions: The MAbs against porcine IRAV, identified by western blot and IFA, provid a valuable tool to study the biological function of IRAV in the future.