Fig. 1

A summary of the regional distribution of intraepithelial lymphocyte (IEL) subsets in human and mouse. We compare here the proportion of T cell subsets between the small intestine (duodenum) and large intestine (colon; right colon in human) while highlighting key differences between human and mouse. Human data is from healthy adults and mouse data is from 8-week-old C57BL/6 specific pathogen-free (SPF) mice from our colony at the University of Chicago. a The proportion of TCRγδ⁺ IEL among CD3⁺ IEL is summarized for human and mouse in duodenum and colon. The proportion of TCRαβ⁺CD8αβ⁺ and TCRαβ⁺CD8αα⁺ among TCRαβ⁺CD4⁻ IEL and TCRαβ⁺CD4⁺ IEL among TCRαβ⁺ IEL is summarized for human and mouse in duodenum and colon. Ranges are based on published data in addition to our own unpublished data. b Freshly isolated IEL⁴⁶ were stained with fluorescently labeled antibodies against CD45, CD3, TCRγδ, TCRαβ, CD4, CD8α, CD8β, and CD103 (human only). Top: representative flow cytometry contour plots with outliers and large dots are shown for the indicated populations (pre-gate indicated above plot) for human (left) or mouse (right) duodenum and colon. Bottom: the proportion of a given cell subset is summarized between the duodenum and colon for both human and mouse. For example, the proportion of TCRγδ⁺ IEL among CD3⁺ IEL in human is lower in the duodenum relative to the colon. The comparisons are made directly between the duodenum and colon, therefore the linear depiction of increases/decreases in proportions between the two segments are meant for simplicity and not to illustrate the progression across the other segments of the gut