Immunological effect of irreversible electroporation on hepatocellular carcinoma

BackgroundThis study intends to investigate the immunological effects of tumor ablation with irreversible electroporation (IRE).MethodsWe evaluated the systemic immune response in patients with hepatocellular carcinoma (HCC) after IRE treatment. Furthermore, we analyzed the tumor infiltrating T lymphocytes and the level of serum cytokines in IRE and control groups of tumor-bearing mice.ResultsWe observed that IRE induced an increase in WBC, neutrophil and monocyte counts and a decrease in lymphocyte count 1day post-IRE and returned to baseline values within 7days in the patients. Meanwhile, circulating CD4(+) T cell subsets, but not CD8(+), decreased 1day post-IRE. The activated T cells and natural killer (NK) cells increased, and regulatory T (Treg) cells decreased. Furthermore, a significant increase in cytotoxic CD8(+) T cells infiltration was observed on ablative tumors in mice. The level of serum IFN-gamma also significantly increased in the IRE group.ConclusionsOur study demonstrated that IRE upregulated activated T cells and downregulated Tregs in the peripheral blood of patients. Meanwhile, the results from the animal model indicated that IRE could induce antitumor adaptive immunity dominated by the infiltration of cytotoxic CD8(+) T cells into the tumors, accompanied by reduced Tregs.

Automated summary

The study showed that IRE treatment increased the counts of WBC, neutrophils, and monocytes while decreasing lymphocyte count in patients. It also indicated a decrease in CD4(+) T cell subsets 1day post-IRE, with an increase in activated T cells and NK cells, and a decrease in Treg cells. Furthermore, there was a significant increase in cytotoxic CD8(+) T cells infiltration in ablative tumors in mice, along with elevated serum IFN-gamma levels in the IRE group.