Fig. 2
From: Immunotherapy of thymic epithelial tumors: molecular understandings and clinical perspectives
Naïve T cell development in the normal thymus and thymoma. A. A healthy thymus with a normal structure and thymic microenvironment determines normal T cell development and maturation and continuously exports normal naïve T cells to establish normal immune function. B. Thymic epithelial tumors with distorted structures and disrupted microenvironments lack components that are necessary for positive and negative selection. Naïve T cells do not complete the central immune tolerance and emigrate to become autoreactive RTEs, which directly or indirectly lead to autoimmune diseases through the cellular or humoral immune systems, respectively. Pro T: Progenitor T cells; AChR: Acetylcholine receptor; AIRE: Autoimmune regulator effectors; RTEs: Recent thymic emigrants; DC: Dendritic cells; SLO: Secondary lymphoid organs