Division of Stem Cells and Cancer, German Cancer Research Center, D-69120 Heidelberg, Germany.
J Exp Med. 2011 Mar 14;208(3):421-8. doi: 10.1084/jem.20110132.
Stem cell niches are defined as the cellular and molecular microenvironments that regulate stem cell function together with stem cell autonomous mechanisms. This includes control of the balance between quiescence, self-renewal, and differentiation, as well as the engagement of specific programs in response to stress. In mammals, the best understood niche is that harboring bone marrow hematopoietic stem cells (HSCs). Recent studies have expanded the number of cell types contributing to the HSC niche. Perivascular mesenchymal stem cells and macrophages now join the previously identified sinusoidal endothelial cells, sympathetic nerve fibers, and cells of the osteoblastic lineage to form similar, but distinct, niches that harbor dormant and self-renewing HSCs during homeostasis and mediate stem cell mobilization in response to granulocyte colony-stimulating factor.
干细胞龛被定义为与干细胞自主机制一起调节干细胞功能的细胞和分子微环境。这包括控制静止、自我更新和分化之间的平衡，以及响应应激时特定程序的参与。在哺乳动物中，最被理解的龛是骨髓造血干细胞 (HSC) 的栖息地。最近的研究扩展了对造血干细胞龛形成有贡献的细胞类型的数量。血管周间充质干细胞和巨噬细胞现在与先前鉴定的窦状内皮细胞、交感神经纤维和成骨细胞谱系的细胞一起，形成类似但不同的龛，在稳态期间容纳休眠和自我更新的 HSC，并在响应粒细胞集落刺激因子时介导干细胞动员。
