Fig. 1
From: Engineering approaches for regeneration of T lymphopoiesis
T cell development in thymic microcompartments. Bone-marrow derived hematopoietic stem/progenitor cells (green) enter the thymus through post-capillary venules and differentiate into T lineage cells (orange). Double negative (DN) thymocytes migrate outward in cortex (light blue region) as they interact with cortical TECs (cTECs, pink) and receive Notch signaling. DP thymocytes undergo positive selection as they migrate back to cortico-medullary junction interacting with pMHC expressed on cTECs. Positively selected thymocytes migrate into medulla (dark blue). SP thymocytes undergo the majority of negative selection within medulla by being tested for reactivity to tissue-restricted self-antigens expressed by medullary TECs (mTECs, purple) or dendritic cells (DCs, yellow). Mature SP thymocytes reciprocally promote maturation of mTECs by LTβR signaling. Mature T cells exit the thymus via blood or lymph. Modified from ref. [5] and [60]