New insights into the cell biology of hematopoietic progenitors by studying prominin-1 (CD133).

Prominin-1 (alias CD133) has received considerable interest because of its expression by several stem and progenitor cells originating from various sources, including the neural and hematopoietic systems. As a cell surface marker, prominin-1 is now used for somatic stem cell isolation. Its expression in cancer stem cells has broadened its clinical value, as it might be useful to outline new prospects for more effective cancer therapies by targeting tumor-initiating cells. Cell biological studies of this molecule have demonstrated that it is specifically concentrated in various membrane structures that protrude from the planar areas of the plasmalemma. Prominin-1 binds to the plasma membrane cholesterol and is associated with a particular membrane microdomain in a cholesterol-dependent manner. Although its physiological function is not yet determined, it is becoming clear that this cell surface protein, as a unique marker of both plasma membrane protrusions and membrane microdomains, might reveal new aspects of the cell biology of rare stem and cancer stem cells. The aim of this review is to outline the recent discoveries regarding the dynamic reorganization of the plasma membrane of rare CD133+ hematopoietic progenitor cells during cell migration and division. (c) 2007 S. Karger AG, Basel.