FROM STEM-CELLS TO LYMPHOCYTES - BIOLOGY AND TRANSPLANTATION

We review the development of the hematopoietic system, focusing on the transition from hematopoietic stem cells (HSCs) to T cells. This incl udes the isolation of HSCs, and recent progress in understanding their ontogeny, homing properties, and differentiation. HSC transplanta tio n is reviewed, including the kinetics of reconstitution, engraftment a cross histocompatibility barriers, the facilitation of allogeneic engr aft ment, and the mechanisms of graft rejection. We describe progress in understanding T-cell development in the bone marrow and thymus as w ell as the establishment of lymph nodes. Finally, the role of bcl-2 in regulating homeostasis in the hematopoietic system is discussed.