( Department of Biochemistry, Laboratory of Molecular Biology, Shanghai Second M edical University, Shanghai 200025, China )

Abstract

rVV(recombinant vaccinia virus) expressing minigene products and rVV expressing full length OVA protein were used to infect several eukaryotic cells . Monoclonal antibody 25.D-1.16(anti-OVA257-264K^b) was used to detec t the confo rmation of H-2K^b-OVA complex on the surface of these cells. The tetramer technique was used to determine their ability to induce antigen specific T cells. The results showed that the tetramer had been generated successfully. Moreover, L929-K^b cells infected by rVV-OVA can be used as APC to induce CTL response. Specific CTL response was demonstrated by H-2K^b-OVA tetramer staining and cytotoxicity assay. Extracelluar IFN-γ was also quantitatively analyzed. The results from H-2K^b-OVA tetramer staining were consistent with cytotoxicity assay. It can be concluded that rVV expressing minigene product is a more efficient source of peptides for class I molecules, and can be more immunogenic than rVVs expressing full length proteins.