Adhesive Interactions in the Hematopoietic System: Regulation by Cytokines

Five years ago, in collaboration with the late Medhi Tavassoli (1) we wrote a minireview on the adhesive interactions taking place in bone marrow and their functional significance (2). In that review the emphasis was placed on the homing mechanisms of progenitor cells to the marrow stroma. Although, at that time information was available on other adhesive processes occurring at the progenitor-stroma interphase, the data were mainly descriptive. Recent research has not only expanded the knowledge about the adhesive mechanisms operating in bone marrow, but has resulted in a wider understanding of their role in steady-state and diseased hematopoiesis. Moreover, new data have illustrated the way in which the expression and/or function of several cytoadhesive molecules or their respective ligands is modulated by cytokines. The latter will be briefly reviewed in this article.