The nurse cells of T-lymphocytes

Abstract

The thymus is an essential organ of the immune system that receives the immature T-lymphocytes coming from the bone marrow. It eliminates defective or auto-reactive lymphocytes and stimulates the maturation of the rest, mainly the helper and regulatory T-cells. The nurse cells of the thymus are epithelial cells that endocyte immature T-lymphocytes by invaginating their membrane and conserving them in vacuoles that express caveolinae and MHC Class II antigens. It is likely that positive and negative selection of immature T-lymphocytes depend on the recognition of those MHC antigens. The intra-thymic process of maturation and selection of T lymphocytes is modulated by the central and vegetative nervous systems. Some T-lymphocytemediated hypersensitivity diseases may have their origin on the umbalanced thymic modulation and/or a deficient work of the thymic nurse cells.