Dr. You-Wen He and his collaborators have recently published exciting new research in Cancer Discovery (September 2016) which shows that complement and interleukin 10 (IL-10) can influence the ability of cytotoxic T cells to kill tumor cells. Complement is essential for many aspects of immune function, but this research group found that complement normally inhibits anti-tumor immune responses and permits the growth of tumors in mice. They showed that complement has this effect because it binds to receptors on tumor-infiltrating lymphocytes (TILs) and prevents them from producing IL-10. Notably, they found that this cytokine supports the growth and killing activity of TILs. Based on these results, the researchers suggest that novel therapies incorporating IL-10 treatment or blockade of complement receptors will help the immune system fight cancer. Learn more.