LAUSR

Minimally invasive thermal therapies have been attempted in the treatment of breast cancer, and the immune response induced by these therapies has not been fully reported. A clinical trial is performed to determine the effect of microwave ablation (MWA) in the treatment of early-stage breast cancer. The authors perform single-cell RNA sequencing on peripheral blood mononuclear cells (PBMCs) from six patients before and after ablation. NK and CD8+ T cells are activated by MWA of breast cancer, with the increased inhibitory signature of CD8+ T cells but not dysfunctional. Enhanced co-stimulatory signature of CD4+ T cells is observed and increased frequency of ICOS+ CD4+ T cells after MWA is confirmed by flow cytometric analysis. After ablation, T-cell clones expand with increased T-cell receptor diversities. Activated antigen receptor-mediated signaling pathways are found in B cells. Enhanced interactions between B cells and CD4+ T cells are found, indicating that B cells are important antigen-presenting cells that initiate CD4+ T cells in MWA-induced immune response. Blockade of CTLA-4 or PD-1 of post-MWA PBMCs show higher T-cell activity than that of pre-MWA PBMCs. This study provide global characteristics of MWA-induced systemic immune response and pave a way for the identification of potential targets to improve the immune response.