MARCH 8 controls surface MHC II expression in TECs. (A) Spleen and thymus DCs or TECs were isolated from wild-type or March1^−/− mice, and surface MHC II was examined by flow cytometry. Data are representative of at least two independent experiments. (B) Diagram illustrating generation of March8^−/− mice. TGA indicates a stop codon. (C) Spleen and thymus DCs or TECs were isolated from wild-type, March8^−/−, or March1^−/− March8^−/− mice, and surface MHC II was analyzed by flow cytometry. Data are representative of at least two independent experiments. (D) MHC I expression by wild-type and March1^−/− DCs and March8^−/− TECs. (E) MHC II expression by wild-type and March8^−/− cTECs and AIRE⁻ and AIRE⁺ mTECs. Data are pooled from two to five independent experiments and are mean + SEM. ***, P < 0.0001, unpaired Student’s t test. MFI, mean fluorescence intensity; n.s., not significant. (F) Expression of CD80 and CD86 by wild-type and March8^−/− TECs. Data are representative of at least two independent experiments.