title: The thymus and the immune system: layered levels of control.
abstract: Control points of normal thymopoiesis may provide insights into strategies for interrupting cell interactions in thymomas which appear to maintain active T cell production. Thymus production of T cells represents one of two pathways by which peripheral T cell populations are maintained or, if lost, regenerated. The production of T cells by the thymus results from a series of thymus epithelial cell (TEC) - thymocyte interactions from entry of thymocyte precursors into the thymus to release of mature naïve single positive T cells into the periphery. Within this series of interactions, certain control points have been identified, all of which act through TEC to modulate thymopoiesis.
authors.affiliation: Experimental Transplantation and Immunology Branch, Center for Cancer Research, NCI, Bethesda, Maryland 20892, USA.
authors.forename: Diana K
authors.initials: DK
authors.lastname: Lee
authors.forename: Frances T
authors.initials: FT
authors.lastname: Hakim
authors.forename: Ronald E
authors.initials: RE
authors.lastname: Gress
mesh_terms: D000818:Animals; D006801:Humans; D007107:Immune System / Q000502:physiology; D013601:T-Lymphocytes / Q000166:cytology / Q000276:immunology*; D013945:Thymoma / Q000276:immunology* / Q000473:pathology; D013950:Thymus Gland / Q000166:cytology / Q000276:immunology*