UC San Diego

Immunological memory is a hallmark property of the adaptive immune system. Following antigen clearance, T cells form specialized subsets capable of rapidly responding to antigen re-encounter. A recently described subset of memory T cells is tissue resident memory (TRM), which provide frontline protection against pathogens and emerging malignancies. Tumor infiltrating lymphocytes with TRM features are associated with improved clinical outcomes. While tremendous progress has been made deciphering the transcriptional regulation of T cell subsets, the cellular interactions which govern T cell differentiation and function in non-lymphoid tissues are not well understood. Here, we leveraged genetic models and state of the art spatial transcriptomics to identify a key role for the chemokine XCL1 and its functional partner, XCR1+ dendritic cells in CD8+ T cell tissue residency and anti-tumor activity.