Cloning, prokaryotic expression, and biological analysis of recombinant chicken IFN-gamma

The full-length chicken interferon-gamma (CHIFN-gamma) gene was amplified by reverse transcription-PCR using total RNA extracted from the spleen cells of white Leghorn chicken, a local Chinese breeding species. A truncated CHIFN-gamma gene without the N-terminal signal peptide sequence was cloned into prokaryotic expression vector pET30a, resulting in a recombinant plasmid pET-30a-CHIFN-gamma. After the recombinant plasmid was transformed into host cells BL21(DE3)pLysS, the expression of CHIFN-gamma was induced by isopropyl beta-D-thiogalactoside (IPTG). Rabbit antiserum was raised using the soluble CHIFN-gamma as immunogen. Immunoreactivities of the CHIFN-gamma and its antiserum were investigated using immunoblotting and ELISA. Moreover, the antiviral effect of the CHIFN-gamma was analyzed. Our data indicate that the CHIFN-gamma is biologically active.