Identification and functional structure predication of mucosal antigen VlhA4.12 from HS strain of Mycoplasma gallisepticum

LU Shi-juan;ZHOU Zhou;ZHU Yi-jing;HU Si-shun;LI Zi-li;LIU Mei;PENG Fu-hu;XIAO Yun-cai;BI Ding-ren;College of Veterinary Medicine, Huazhong Agricultural University;Key Laboratory of Development of Veterinary Diagnostic Products of Ministry of Agriculture;Hubei Center for Animal Disease Control and Prevention;

Mycoplasma gallisepticum strain HS;;chicken respiratory disease;;tracheal washes;;mucosal immunity;;VlhA4;;12

To investigate the antigens of Mycoplasma gallisepticum(MG) involved in stimulation of local immune responses in the respiratory tract of MG-infected chicken, sera and tracheal washes with PBS(p H7.4) were collected from chicken inoculated with 100 folds concentrated MG strain HS for 2 weeks and used as 1stantibody in western blot to react with lysates of MG HS strain. As results, a 75 ku protein, homology to VlhA4.12 of MG strain R indentified by Mass spectrometry analysis, was screened to react with both IgA and IgY in respiratory tract washes. Several antigenic epitopes of B cell and T cell were predicated in the protein, indicating a candidate antigen of mucosal immunity. To prepare recombinant VlhA4.12(rVlhA4.12), 4 TGAs encoding Sers in vlhA4.12 gene were sense-muted as TGGs and then expressed in Ecoli BL21(DE3) after cloning into p ET-32 a. The recombinant VlhA4.12 showed immunity as antigen and reacted with specific antibodies including Ig A and Ig Y in the respiratory tract washes and serum of MG HS infected chicken. Our results could provide new idea of investigating vaccine candidate antigen of MG and developing new mucosal vaccine.