Figure 2. CD8⁺ cells had the same response to ATRA as did CD4⁺ cells.

(A) The expression of ATRA RARα mRNA was determined by quantitative RT-PCR on naive or activated CD4⁺ and CD8⁺ cells. These cells were activated with TCR and IL-2, with or without TGF-β and with or without ATRA. Data are the mean ± se of 3 separate experiments. (B) CD4_TGFβ, CD8_TGFβ, CD4_TGFβ+ATRA, or CD8_TGFβ+ATRA cells were induced as in Fig. 1A, and the expression of CD44 and CD62L gated on CD4 or CD8 was analyzed by flow cytometry. Dot plots are representative of 3 independent experiments. (C) The expression of α₄β₇ and CCR-9 on CD4_med, CD8_med, CD4_TGFβ, CD8_TGFβ, CD4_TGFβ+ATRA, or CD8_TGFβ+ATRA cells was analyzed by flow cytometry. Data are representative of 3 independent experiments showing staining (black) plus isotype control (gray).