Abstract: In order to prepare polyclonal antibodies of the fragment of bovine integrin β7 subunit. According to the bovine integrin β7 nucleotide sequence reported in the GenBank，the fragment of β7 subunit was synthetized. Expression vector was constructed by using DNA recombination technology. After being induced by IPTG，the fragment of β7 was expressed in E.coli. The expression product was identified by Western blotting. Results showed that the fragment of β7 with relative molecular mass of 15 ku was expressed successfully in E.coli. The expression product was purified by Ni-NTA resin. Then，the polyclonal antibody was prepared by inoculating rabbits with β7 purified product. The ELISA titer of the polyclonal antibody was approximately 1∶32000. The results of this study lay a foundation for further study of the function of bovine integrin α4β7.

Key words: integrin β7; prokaryotic expression; polyclonal antibody