Some dynamic aspects of hematopoietic stem cells.

Hematopoiesis is the process responsible for maintaining the number of circulating blood cells that are undergoing continuous turnover. At the root of this process are the hematopoietic stem cells (HSC). In the following we discuss various dynamic aspects of HSC behavior ranging from the number of active stem cells, their expansion during ontogeny and the importance of stochastic effects on their behavior. We show how mathematical modeling of HSC behavior can provide important insights on these cells and clarify the implications of these dynamical aspects on healthy and sick individuals, as such providing rational explanations for relevant clinical observations on disorders that originate in this group of cells.