CD4+ (A) and CD8+ (B) T cells from gut and FRT were reclustered (C1-C9, and D1-D10) by FlowSOM, after removal of the blood specimens’ data. The top portions of the two panels show cluster distributions depicted as pie charts, separated by donor. The bottom portions of the two panels depict bar graphs of clusters that were significantly over-represented in gut or FRT. Validation of markers preferentially expressed on gut CD4+ (C) and CD8+ (D) T cells was then performed by selecting antigens differentially expressed in the clusters enriched in the gut as compared to FRT (C2 and D2), and conducting manual gating. This analysis demonstrated that relative to their FRT counterparts, both CD4+ and CD8+ T cells from gut are preferentially CD45ROhighCD69highCCR7lowCD27low. * p < 0.05 and ** p < 0.01 as determined by a Mann-Whitney U test (n=5 donors).