Analysis of antigenicity in four antigenic candidate genes of Lawsonia intracellularis GXNN strain

According to the associated protein sequences of Lawsonia intracellularis published in GenBank,four pairs of primers were designed and the genes of three outer membrane proteins and one ectal lipoprotein were amplified.After constructing the prokaryotic expression vectors for four antigenic candidate genes,the prokaryotic expression,SDS-PAGE electrophoresis and Western blotting analysis were performed.The results showed that two recombination fusion proteins pET32a-LI0902 and pET32a-LI1022 could be expressed and 57kDa and 37kDa band was obtained by SDS-PAGE electrophoresis,respectively.The Western blotting analysis results showed that pET32a-LI1022 had antigenicity.These re-sults for the first time proved that whether outer membrane proteins of Lawsonia intracellularis had antigenicity or not,and would provide theoretical basis for developing diagnostic kit and genetically engineered vaccine.