Numerous subsets were over-represented among PRE cells, relative to UI CD4+ T cells (Tcm, Ttm, Tfh, Th1, Th17, and CD4+ T cells that were α4β7+ or α4β1+ for in vivo specimens; and Tem, Ttm, Th1, Th1/Th17, and CD4+ T cells that were α4β7+ for in vitro specimens), suggesting preferential infection of these subsets. Here, CD4 is linked to infection.