Expression of Chicken Interleukin-18 in E.coli and Preparation of Its Antiserum

To highly express chicken Interleukin 18(ChIL 18) in E.coli and purify the fusion protein, cDNA fragment encoding the mature ChIL 18 was subcloned into the prokaryotic expression vector pPROEXTMHT. The recombinant plasmid was transformed into E.coli, and then induced by IPTG at 37℃. The recombinant ChIL 18(rChIL 18) was expressed efficiently in forms of inclusion body with the yield accounting for 30% total bacteria protein. SDS PAGE and Western blot analysis showed that the recombinant fusion protein had a molecular weight approximately 23 000 . The inclusion body was solubilized by 6 mol/L Guanidine hydrochloric acid and purified by ProBond TM Resin. The antiserum against rChIL 18 was obtained by injecting the guinea pig with fusion rChIL 18 protein. As a result, we successfully expressed and purified the rChIL 18 fusion protein from E.coli and obtained the antiserum against rChIL 18, laid a foundation and prepared experimental material for the future studies on the bioactivity of rChIL 18.