Increased CD11b⁺LAP⁺ cells and IL-13–producing CD4⁺ T cells and reduced IFN-γ–producing CD4⁺ T cells in the skin of CD19^−/− donor-transplanted mice. A skin cell suspension was generated by digesting a 3 × 3-cm piece of depilated skin and was stained for surface markers and to differentiate live cells from dead cells. (A) The number of skin T cells (Thy1.2⁺) and (B) ratio of CD8⁺:CD4⁺ T cells were analyzed 21 days after BMT. A skin single-cell suspension was intracellularly stained with LAP (TGF-β1). (C) The number of CD11b⁺LAP⁺ cells, and (D) representative histograms from a live cell gate show the percentage of CD11b⁺LAP⁺ cells. Skin single-cell suspensions from CD19^+/+ donor and CD19^−/− donor-transplanted groups were cultured with PMA, ionomycin, and brefeldin A for 4 hours for detection of cytokine-producing T cells. Percentages of (E) IFN-γ–, (F) IL-17A–, and (G) IL-13–producing CD4⁺ T cells in total CD4⁺ T cells were analyzed. (H) Representative histograms from the CD4⁺ gate show the percentage of IL-13–producing CD4⁺ T cells; 4 to 5 mice per group. *P < .05; **P < .01.