Fig. 5. CD103 is actively maintained on naive CD8⁺ T cells through αV-integrin-expressing DCs.

(A) ImmGen database RNA-seq gene expression analysis of naive CD8⁺ T cells. Green bars denote selected genes known to be expressed at the protein level in naive T cells, red bars denote selected genes known to be expressed at very low levels or not to be expressed in naive T cells. Black bars denote skin eT_RM cell genes having greater accessibility in naive CD8⁺ T cells from WT as compared to αV-ΔDC mice. White bars denote other skin eT_RM cell genes not differentially accessible in cells from WT compared to αV-ΔDC mice. (B) Expression of CD103 on CD44^lo CD62L^hi naive CD4⁺ and CD8⁺ T cells (pooled from LNs and spleen) and on thymocyte subsets from αV-ΔDC and WT littermate control mice. Data are means and replicates and representative of four independent experiments. (C) 10⁶ naive polyclonal CD8⁺ T cells from αV-ΔDC were adoptively transferred into CD45.1 congenic C57BL/6 mice or vice versa and re-isolated 3 weeks later from pooled LNs and spleens for analysis of CD103 expression. Data are means and replicates and representative of three independent experiments. (D) 10⁶ naive OT-I T cells were adoptively transferred into αV-ΔDC or WT hosts and isolated from pooled LNs and spleens 3 weeks later for analysis of CD103 expression. Data are means and replicates and representative of three independent experiments. (E) CD103 expression on CD44^lo naive CD8⁺ T cells from the peripheral blood of WT and αV-ΔDC mice at less than 5 or more than 10 wks of age. Data are means and replicates. */**/***/****: p<0.05/p<0.01/p<0.001/p<0.0001 (Two-tailed unpaired Student’s t-tests in (B-E)).