Fig. 1. Colonic iNKT cells emerge and expand during early life before establishing residency at steady state.

Circulatory exchange of CD45.1 (black) or CD45.2 (grey) TCR-αβ⁺ T (CD45+ CD3ε+ TCRβ+) and iNKT (CD45⁺ CD3ε⁺ TCRβ⁺ CD1d Tetramer⁺) cells in the spleen and colon of surgically joined CD45.1 (left) and CD45.2 (right) congenic animals (n=2) determined by flow cytometry, 3 weeks (A) and 8 weeks (B) after surgery. Circles are representative of average cell frequency. iNKT cell percentage (C) and absolute counts (D) in the colon over time. Each dot is representative of an individual mouse, line is representative of the sample means. E) Schematic of adoptive transfer strategy. (F) Adoptive transfer of CD45.1 adult thymic cells into a 4 day old CD45.2 (n=6) host followed by quantitative analyses of splenic and colonic CD45.1 (black) or CD45.2 (grey) TCR-αβ⁺ T and iNKT cells by flow cytometry on day 11. Representative plots (left). Circles are representative of average cell frequency (right). G) Schematic of adoptive transfer strategy. (H) Adoptive transfer of CD45.1 adult thymic cells into a 49 day old CD45.2 host (n=6) followed by quantitative analyses of splenic and colonic CD45.1 (black) or CD45.2 (grey) TCR-αβ⁺ T and iNKT cells by flow cytometry on day 56. Representative plots (left). Circles are representative of average cell frequency (right). Data were pooled from two experiments [(F) and (H)]. Tet, Tetramer. SSC-A, Side scatter.