Cancer immunotherapy—an approach that removes the barriers that protect cancer cells from a patient’s immune system—has revolutionized the treatment of many cancer types. About 40 percent of melanoma patients, for example, respond to immunotherapy, enabling the immune system’s T cells to attack cancer cells and take control of the disease.

In a study published in the February 6, 2019 issue of Nature, a University of Chicago-based team working in collaboration with scientists at Tsinghua University and the Chinese Academy of Sciences, demonstrates, in mice, that they can boost the tumor control rate from around 40 percent up to nearly 100 percent by opening up a parallel pathway.

This study relies on manipulating these cells, which are a crucial component of the immune system. The primary function of dendritic cells is to process antigens and present them to T cells. They act as messengers, connecting the innate and the adaptive immune systems.

But a protein known as YTHDF1 influences antigen processing by dendritic cells. This protein was discovered and characterized in 2015 by Chuan He, PhD, the John T. Wilson Distinguished Service Professor in chemistry, biochemistry and molecular biology, and the Institute for Biophysical Dynamics at the University of Chicago. YTHDF1 controls the level of proteases that destroy potential tumor antigens. This limits their presentation to T cells.