Maturation and Emigration of Single-Positive Thymocytes

Abstract EN

T lymphopoiesis in the thymus was thought to be completed once it reaches the single positive (SP) stage, a stage when T cells are “fully mature” and waiting to be exported at random or follow a “first-in-first-out” manner.

Recent evidence, however, has revealed that the newly generated SP thymocytes undergo a multistage maturation program in the thymic medulla.

Such maturation is followed by a tightly regulated emigration process and a further postthymic maturation of recent thymic emigrants (RTEs).

This review summarizes recent progress in the late stage T cell development.

The regulation of this developmental process is discussed.