FOXP3 and infection: To investigate how TIGIT limits tissue damage after infection, we performed single-cell RNA sequencing (scRNA-seq) of T cells from the spleen and lung of naive and LCMV Cl13-infected WT and Tigit-KO mice, and we enriched for CD4+Foxp3+ Treg cells to obtain a solid representation of all T cell subsets (Extended Data Fig. 2a).