[Immune regulation of hematopoiesis]

Abstract

Effective hematopoiesis is a multistep phenomenon. It consists in the presence of pluripotent hematopoietic stem cells (HSC), their proliferation and self-maintenance, their differentiation into various committed lineages of specific progenitors, their orderly maturation into functional cells that are released into the circulation in an orderly fashion in response to the body's demand. Increasing numbers of hematopoietic factors are being purified to homogeneity and/or cloned. The availability of sufficient quantities of these regulators promises a new area for research into the physiology and pathophysiology of the hematopoietic system. The purpose of this overview is to consider some newly-developed concepts in the field of hematopoiesis, with regard to regulatory control mechanisms and cellular interactions.