Apoptotic B16-F1 Cells Coated with Recombinant Calreticulin Mediated Anti-tumor Immune Response in Mice

摘要

Objective: To investigate the recombinant calreticulin (rCRT) mediated antitumor immune response. Methods: Cell proliferation was determined by MTT method, apoptosis was evaluated by DNA fragmentation and CRT expression and cell localization were assayed by western blotting, QT-RT-PCR and immunofluorescence assays. The mouse melanoma cell line B16-F1 was treated with polyamine analogue BENS to induce apoptosis and incubated with rCRT to get rCRT coated on the membrane, and then the cells were used to immune BALB/c mice as a cell-antigen. Immunized animals were rechallenged by live B16-F1 cells and then tumor generation ratio and the lactate dehydrogenase release assay were used to evaluate antitumor effects of rCRT-mediated immunity. Results: BENS induced apoptosis of B16-F1 cells without the redistribution of CRT within the cells. When B16-F1 cells coated with rCRT were used as cell-antigen to inoculate the animals, the mice obtained the ability in inhibiting proliferation of homologous tumor cells in vivo. Comparing with the positive control group, the splenocytes from those inoculated mice have an obvious enhancement on their cytolytic effects specifically against B16-F1 cells. Conclusion: rCRT coated on the cell surface can enhance immunogenicity of apoptotic tumor cells and mediated effective anti-tumor immunoresponse in mice.