Granick Jennifer L, Simon Scott I, Borjesson Dori L
Department of Pathology, Microbiology, Immunology, University of California School of Veterinary Medicine, Davis, CA 95616, USA.
Bone Marrow Res. 2012;2012:165107. doi: 10.1155/2012/165107. Epub 2012 Jun 19.
Recent research has shed light on novel functions of hematopoietic stem and progenitor cells (HSPC). While they are critical for maintenance and replenishment of blood cells in the bone marrow, these cells are not limited to the bone marrow compartment and function beyond their role in hematopoiesis. HSPC can leave bone marrow and circulate in peripheral blood and lymph, a process often manipulated therapeutically for the purpose of transplantation. Additionally, these cells preferentially home to extramedullary sites of inflammation where they can differentiate to more mature effector cells. HSPC are susceptible to various pathogens, though they may participate in the innate immune response without being directly infected. They express pattern recognition receptors for detection of endogenous and exogenous danger-associated molecular patterns and respond not only by the formation of daughter cells but can themselves secrete powerful cytokines. This paper summarizes the functional and phenotypic characterization of HSPC, their niche within and outside of the bone marrow, and what is known regarding their role in the innate immune response.
近期研究揭示了造血干细胞和祖细胞（HSPC）的新功能。虽然它们对于骨髓中血细胞的维持和补充至关重要，但这些细胞并不局限于骨髓区域，其功能超出了造血作用。HSPC可离开骨髓并在外周血和淋巴中循环，这一过程常被用于治疗性移植的操作。此外，这些细胞优先归巢至炎症的髓外部位，在那里它们可分化为更成熟的效应细胞。HSPC易受多种病原体感染，尽管它们可能在未被直接感染的情况下参与固有免疫反应。它们表达用于检测内源性和外源性危险相关分子模式的模式识别受体，不仅通过形成子代细胞做出反应，自身还能分泌强效细胞因子。本文总结了HSPC的功能和表型特征、它们在骨髓内外的生态位，以及关于它们在固有免疫反应中作用的已知情况。
