Connexins are active participants of hematopoietic stem cell regulation.

Intercellular communication participates in the regulation of normal hematopoiesis and possibly in neoplastic transformations in the hematopoietic niches. The role of gap junctions (GJs) and their connexins (Cxs) on hematopoietic tissues have been studied since the 1970s. Clearly, GJs are involved in different functional characteristics and connexin expression seems to be thoroughly regulated in hematopoietic tissues, suggesting that these molecules participate in the physiology of hematopoiesis. However, the exact mechanisms of GJs and Cxs are not characterized in detail. In this review we present the major findings of GJs and Cxs in normal hematopoietic tissues, and briefly discuss possible pathways of action and the potential of these molecules in hematopoietic reconstitution after cancer chemotherapy.