Márquez C, Trigueros C, Franco J M, Ramiro A R, Carrasco Y R, López-Botet M, Toribio M L
Centro de Biología Molecular "Severo Ochoa," Universidad Autónoma de Madrid, Madrid, Spain.
Blood. 1998 Apr 15;91(8):2760-71.
Current data support the notion that the thymus is seeded by a yet uncommitted progenitor cell able to generate T cells, B cells, natural killer (NK) cells, and dendritic cells (DCs). We assess in this report the developmental relationship of DCs and NK cells derived from a small subset of CD34(+) human postnatal thymocytes that, like the earliest precursors in the fetal thymus, display low CD33 surface expression. Culture of these isolated CD34(+) CD33(lo) thymic progenitors with a mixture of cytokines, including interleukin-7 (IL-7), IL-1alpha, IL-6, granulocyte-macrophage colony-stimulating factor, and stem cell factor, results in predominant generation of DCs. However, the addition of IL-2 to the cytokine mixture leads to the simultaneous development of DCs and NK cells. Both developmental pathways progress through a transient population of CD34(+)CD44(bright) CD5(lo/-)CD33(+) large-sized cells, distinct from small-sized T-lineage precursors, that contain bipotential NK/DC progenitors. These data provide evidence of linked pathways of NK cell and DC development from intrathymic precursors and suggest that NK cells and DCs branch off the T lineage through a common intermediate progenitor.
目前的数据支持这样一种观点，即胸腺由一种尚未定向分化的祖细胞播种，这种祖细胞能够产生T细胞、B细胞、自然杀伤（NK）细胞和树突状细胞（DC）。在本报告中，我们评估了源自一小部分CD34(+) 人类产后胸腺细胞的DC和NK细胞的发育关系，这些胸腺细胞与胎儿胸腺中最早的前体细胞一样，CD33表面表达水平较低。将这些分离的CD34(+) CD33(lo) 胸腺祖细胞与包括白细胞介素-7（IL-7）、IL-1α、IL-6、粒细胞-巨噬细胞集落刺激因子和干细胞因子在内的细胞因子混合物一起培养，结果主要产生DC。然而，在细胞因子混合物中添加IL-2会导致DC和NK细胞同时发育。这两条发育途径都通过一群短暂存在的CD34(+)CD44(bright) CD5(lo/-)CD33(+) 大细胞进行，这些大细胞不同于小尺寸的T系前体细胞，它们含有双潜能NK/DC祖细胞。这些数据提供了胸腺内前体细胞NK细胞和DC发育相关途径的证据，并表明NK细胞和DC通过共同的中间祖细胞从T系分支出来。
