Origin and fate of the regenerating cells of the kidney.

The kidney has the capacity to regenerate itself provided that the damage is limited and the structure of the kidney remains intact. Nevertheless, in disease conditions this potential may be compromised, leading to progression to chronic kidney disease. For development of new therapeutic strategies it is a prerequisite to understand the origin and regulation of the kidney regenerating cells and the processes that underlie maladaptive repair. Because of the complexity of the kidney consisting of a high number of different cell types, it is a complex task to unravel the origin and fate of cells responsible for regeneration. This review summarises the recent and most important advances in identifying regenerating cell populations of the kidney, and highlights the existing controversies.