The Functional Phenotype of Aged Hematopoietic Stem Cells

Recent findings Aged HSCs are myeloid biased, have acquired DNA damage and are functionally compromised. However, overall function of the HSC compartment is well maintained through age-associated expansion of HSCs. Many age-related changes in the hematopoietic system, in particular the clonal myeloid bias of HSCs and the decrease in B and T-cell development, in fact begin during development. Furthermore, HSCs possess specific protective mechanisms aimed at maintaining their number, even at the expense of accumulating damaged cells.