Musashi M, Ogawa M
Medical University of South Carolina.
Rinsho Ketsueki. 1991 May;32(5):439-46.
The central feature of hematopoiesis is life-long, stable cell renewal. This process is supported by hemopoietic stem cells which, in the steady state, appear to be dormant in cell cycling. The recruitment of the dormant stem cells into cell cycle may be promoted by such factors as interleukin (IL)-1, IL-6, granulocyte-colony stimulating factor (G-CSF), and newly discovered IL-11. The effects of IL-1 on stem cells may be indirect. Once the stem cells leave Go and begin proliferation, the subsequent process is characterized by continued proliferation and differentiation. Though several models of stem cell differentiation have been proposed, micromanipulation studies of individual progenitors suggest that the commitment of multipotential progenitors to single lineages is a stochastic process. The proliferation of early hemopoietic progenitors requires the presence of IL-3 and/or IL-4, and the intermediate process appears to be supported by granulocyte/macrophage-CSF (GM-CSF). Once the progenitors are committed to individual lineages, the subsequent maturation process appears to be supported by late-acting, lineage-specific factors such as erythropoietin (erythropoiesis), G-CSF (neutrophil production), and IL-5 (eosinophilopoiesis). Thus, hemopoietic proliferation appears to be regulated by a cascade of factors directed at different developmental stages.
造血作用的核心特征是终身性、稳定的细胞更新。这一过程由造血干细胞支持，在稳态下，造血干细胞在细胞周期中似乎处于休眠状态。诸如白细胞介素（IL）-1、IL-6、粒细胞集落刺激因子（G-CSF）以及新发现的IL-11等因子可促进休眠干细胞进入细胞周期。IL-1对干细胞的作用可能是间接的。一旦干细胞离开G0期并开始增殖，后续过程的特征就是持续增殖和分化。尽管已经提出了几种干细胞分化模型，但对单个祖细胞的显微操作研究表明，多能祖细胞向单一谱系的定向分化是一个随机过程。早期造血祖细胞的增殖需要IL-3和/或IL-4的存在，中间过程似乎由粒细胞/巨噬细胞集落刺激因子（GM-CSF）支持。一旦祖细胞定向分化为单个谱系，后续的成熟过程似乎由后期起作用的、谱系特异性因子支持，如促红细胞生成素（红细胞生成）、G-CSF（中性粒细胞生成）和IL-5（嗜酸性粒细胞生成）。因此，造血增殖似乎由针对不同发育阶段的一系列因子调节。
