文摘
The imprinted gene Igf2 is expressed in adult tissue stem cells. Igf2 deficiency increases HSC (hematopoietic stem cells) self-renewal and avoids age-related attrition of the HSC pool. Igf2 deficiency decreases HSC differentiation and mobilization. Igf2 deficiency modifies the interaction between HSC and their environment.IGF2 belongs to the IGF/Insulin family that regulates growth, aging and lifespan. This role is evolutionarily conserved from worms to mammals. IGF2 favors cell proliferation during embryonic development but its role in adulthood is unknown. To decipher its function we undertook a lifelong analysis of the consequences of Igf2 deficiency on hematopoiesis, in steady-state conditions and during bone marrow transplantation. We demonstrate that lowering Igf2 levels increases the pool of stem cells, without uncontrolled proliferation and migration of immature cells that would lead to cancer. This is a promising way to enhance the stem cells pool during aging that has major interest for transplantation.