Tumor Antigen Heterogeneity: The Elephant in the Room of Adoptive T-cell Therapy for Solid Tumors

A major hurdle to the efficacy of adoptive cell therapy and chimeric antigen receptors T-cell therapy is the choice of antigen(s) to target. An article in this issue addresses this by capitalizing on the synergistic effect of pathogen-based immunotherapy and adoptive cell therapy that results in epitope/antigen spreading and enhancement of the endogenous T-cell response against antigens not originally targeted.