Construction of recombinant Lactococcuslactis expressing chicken ChIL-12 and its biological activity identification

LIU Lin-lin;SONG Yu-xin;WANG Wen-qian;PAN Qing;QI Xiao-le;GAO Yu-long;LIU Chang-jun;ZHANG Yan-ping;LI Kai;GAO Li;WANG Yong-qiang;WANG Xiao-mei;CUI Hong-yu;Division of Avian Infectious Diseases, State Key Laboratory of Veterinary Biotechnology, Harbin Veterinary Research Institute,the Chinese Academy of Agricultural Sciences;

Chicken IL-12;;recombination Lactococcuslactics;;biological activities;;mucosal vaccine adjuvant

Chicken interleukin-12(ChIL-12) is a heterodimeric cytokine consisted with IL-12p40 and IL-12p35 subunits.ChIL-12 has the ability to promote the mature of T cells and natural killer cells(NK cell), which is used as a mucosal vaccine adjuvant. In this study, the IL-12p40 and IL-12p35 subunit genes were fused with a glycine-serine linker encoding sequence by PCR, and cloned into the plasmid of pNZ8149 for expression in the food-grade NZ3900 strain of Lactococcus lactis. Western blot detection showed that the recombinant Ch L-12 fusion protein(rChIL-12) was expressed in a soluble form in the cytoplasm.Moreover, the r ChIL-12 was able to induce chicken splenic mononuclear cells to produce interferon-γ verified by the chicken lymphocyte stimulation test in vitro. These results demonstrated that the rChIL-12 has the biological activity, which laid the foundation for further study of r ChIL-12 as a mucosal vaccine adjuvant.