Mountaineering pericytes--a universal key to tissue repair?

Pericytes, typically attached to the walls of microvessels in almost all organs, interact with endothelial cells and take part in diverse biological processes, e.g. blood vessel regulation and tissue repair. This suggests that pericytes harbor a remarkable degree of cellular plasticity, which could potentially be employed for the treatment of diseases affecting diverse tissues such as the skeletal muscle and the central nervous system. Here, we follow pericytes on their journey across Waddington's epigenetic landscape, descending from their origin, along a path guided by environmental signals or ectopic transcription factors, at the end of which they acquire a new identity, e.g. muscle or nerve cells. The central theme of this review is the question of whether pericytes can be enticed to differentiate into whatever cell type is needed, and thus provide an endogenous cellular source for treating as yet incurable diseases--like a magic bullet.