The preparation of leukemia cell vaccine expressing BCG heat shock protein 70 and anti-leukemia effect in vitro

Gene-modified cell vaccines are the best way to achieve the immunotherapy for all types of acute leukemia. In this study, heat shock protein 70 (HSP70) gene of BCG was transfected into the acute leukemia cells and its anti-leukemia effect was further studied. Results showed that short-term culture of the leukemia cells exhibited increased number and no change in antigen expression. After HSP70 gene transfection, the yellow-green fluorescence on the leukemia cell surface was observed under a fluorescence microscope. The immunogenicity of HSP70-transfected cells exhibited that autologous lymphocytes proliferated significantly and secreted higher amount of IFN-γ, and cytotoxic T lymphocytes induced more beneficial anti-leukemia effects. These results suggested that gene transfection of BCG HSP70 could significantly enhance the immunogenicity of leukemia cells. It may be used as a suitable candidate gene-modified cell vaccine for cancer immunotherapy.