Putting on the gas and taking off the brakes: A novel combinatorial strategy to enhance tumor-infiltrating lymphocytes

The advent of checkpoint blockade and use of cytokines to enhance immune responses have changed the field of immunotherapy. Yet, these approaches are not without drawbacks including systemic toxicities and acquired therapeutic resistance. In this issue, Xu and colleagues describe a novel biological molecule composed of a PD-1-targeting antibody linked to a mutated IL15 that induces better targeting of IL15 to tumor-infiltrating lymphocytes (TIL) to decrease systemic toxicities and enhance antitumor responses. See related article by Xu et al., p. 1141 (1).