IL-17A promotes migration and tumor killing capability of B cells in esophageal squamous cell carcinoma.

We have previously reported that the accumulation of IL-17-producing cells could mediate tumor protective immunity by promoting the migration of NK cells, T cells and dendritic cells in esophageal squamous cell carcinoma (ESCC) patients. However, there were no reports concerning the effect of IL-17A on tumor infiltrating B cells. In this study, we investigated the accumulation of CD20+ B cells in the ESCC tumor nests and further addressed the effect of IL-17A on the migration and cytotoxicity of B cells. There was positive correlation between the levels of CD20+ B cells and IL-17+ cells. IL-17A could promote the ESCC tumor cells to produce more chemokines CCL2, CCL20 and CXCL13, which were associated with the migration of B cells. In addition, IL-17A enhanced the IgG-mediated antibody and complement mediated cytotoxicity of B cells against tumor cells. IL-17A-stimulated B cells gained more effective direct killing capability through enhanced expression of Granzyme B and FasL. The effect of IL-17A on the migration and cytotoxicity of B cells was IL-17A pathway dependent, which could be inhibited by IL-17A inhibitor. This study provides further understanding of the roles of IL-17A in humoral response, which may contribute to the development of novel tumor immunotherapy strategy.