Lymphocyte and lymphoma receptors utilized in differentiation, in homing, and in lymphomagenesis

The thymus is believed to be the major, if not the sole site of differentiation of T lymphocytes [1, 2]. During fetal development the thymus receives a bolus of precursors of T cells from the hematopoietic organs, probably the fetal liver and/or the yolk sac [3, 4]; these populations subsequently undergo self-renewal as well as maturation [5]. In adult life the thymus receives cells from the bone marrow at a very low level, but in times of stress, or after irradiation, there is a massive renewal of cells in the thymus from bone marrow precursors [2]