Construction of the eukaryotic coexpression vector of SEA and murine B7-1 and its expression in B16 cell line

Objective To construct the eukaryotic coexpression vector of SEA and murine B7-1. Methods The SEA with B7-1 transmembrane region (SEA -B7tm) and the murine B7-1 gene were cloned by PCR and RT-PCR, respectively. SEA-B7tm and B7-1 were linked by IRES sequence and cloned into eukaryotic expression vector pcDNA3.1+. The recombinant plasmid was transfected into B16 cell line by lipofectamine reagent. The expressions of B7-1 and SEA were observed by double-labeling indirect immunofluorescent stain. Results The cloned SEA-B7tm and the murine B7-1 gene were identical to those reported in GeneBank. The B7-1 and the SEA were simultaneously expressed on the membrane of B16. Conclusion The eukaryotic coexpression vector of SEA and murine B7-1 is constructed successfully. The results give a basis for coapplication of B7 and SEA in tumor treatment and research of its immunological mechanisms.