Figure 1

Positive and negative T cell selection in the thymus depends in part on macroautophagy. Cortical and medullary thymic epithelial cells (cTECs and mTECs), as well as thymic dendritic cells (DCs), constitutively perform macroautophagy. Loss of macroautophagy in the thymus compromises positive selection of some T cell specificities on MHC class II molecules (MHC class II) from double-positive (dpT) to single-positive CD4⁺ T cells (CD4⁺ T) by cTECs. Macroautophagy deficient thymi have also diminished negative selection of CD4⁺ T cells by DCs and/or mTECs with promiscuous self-antigen expression due to Aire transcription.