To study the relationship between the gene-expression programs and locations of TRM cells, we adoptively transferred female P14 CD8 T cells to male mice, infected them with LCMV and performed spatial transcriptomic profiling (Xenium, 10x Genomics)17,18 on mouse SIs over the course of the LCMV infection (6, 8, 30 and 90 days post infection (d.p.i.)). Here, CD8A is linked to infection.