[Objective] To investigate the immunogenicity of fusion protein S1-TAT consisting of transmissible gastroenteritis virus S1 and transcriptional activator protein( TAT). [Method] The recombinant plasmid S1-TAT was expressed in prokaryotic system and purified. Kunming mice were immunized with fusion protein S1-TAT by intraperitoneal injection and intragastric administration respectively,collected the blood and stool samples of mice and determined for serum Ig G and mucosal Ig A antibody,observed the change of...