Enhancement of dendritic cell immunotherapy by recalling antigens for hepatocellular carcinoma in mice

Background: The therapeutic efficacy of dendritic cell (DC)-immunotherapy for large hepatoma in mice is unsatisfactory. Materials & methods: DC-based immunotherapy was used to treat Hepa1-6 tumors measuring 6 ± 1 mm in diameter, enhanced by boosting tumor antigens. Results: CD4+ and CD8+ T-cells were contracted and transformed into memory phenotypic cells after DC-based vaccination. When T-cells were re-stimulated, T-cells obtained from mice boosted by tumor antigen injection showed highest proliferation capacity. When mice with large tumors were treated, DC-based vaccination boosted by tumor antigen and an additional DC-infusion yielded curative rates of 50% and 23.1%, respectively. Conclusion: DC vaccination induced effector memory cells. Antigen presentation recalled by DC or tumor antigens increased the curative rate in mice with large tumors. Plain language summary Hepatocellular carcinoma is the most common liver malignancy and is often found at advanced stage. Immune checkpoint inhibitor combined with a molecular targeting agent is a new strategy for the treatment of advanced hepatocellular carcinoma and yields 30% of objective response rate. However, we still need another treatment for the patients who are not responsive to immune checkpoint inhibitor combined with a molecular targeting agent. Dendritic cell-based immunotherapy is one of the treatments for advanced hepatocellular carcinoma. In this animal study, dendritic cells can activate T-lymphocytes to kill cancer cells. Dendritic cells can also induce memory T-lymphocytes, which can be reactive by boost tumor antigens and increase therapeutic efficacy. This treatment strategy, dendritic cell infusion followed by tumor-antigen injection, can be translated into clinical practice in the future.