ABSTRACT
<p><b>OBJECTIVE</b>To investigate the induction of antitumor immune responses and therapeutic effects of 10-hydroxycamptothecinc-treated (HCPT) DC-Hepa fusion vaccines by DC fused with hepal-6 cell from hepatoma.</p><p><b>METHODS</b>The fused cells were isolated by magnetic cell sorting and adherent culture. Cell apoptosis was detected by Rhodamine123/PI double-labeled assay, CTL activity by 4 h (51)Cr releasing assay. Protective and therapeutic effects of the fusion vaccine to the tumor-bearing mice was also observed.</p><p><b>RESULTS</b>The apoptosis rate was 29.7%+/-4.1% when DC-Hepa fusion vaccine was treated with 50 microg/ml HCPT for 24 h. After treatment with the HCPT-DC-Hepa fusion vaccine, the tumor grew obviously slowly, survival period of the mice was prolonged, induced more potent CTL cytotoxicity, and resisted against the rechallenge of Hepal-6 cells.</p><p><b>CONCLUSION</b>Vaccination with HCPT-DC-Hepa fusion vaccine could elicit potent antitumor responses, which will provide a new approach to the DC-mediated therapeutic antitumor immunity.</p>