Szabolcs P, Ciocon D H, Moore M A, Young J W
Laboratory of Cellular Physiology and Immunology, Rockefeller University, New York, New York 10021, USA.
Adv Exp Med Biol. 1997;417:15-9. doi: 10.1007/978-1-4757-9966-8_3.
Human dendritic cells can be generated from bone marrow CD34+ progenitors in the presence of GM-CSF and TNF alpha. The addition of a factor like c-kit-ligand optimizes the expansion of dendritic cells, as well as the other myeloid progeny grown under the same conditions, and facilitates their identification and characterization. In contrast to cord blood, where dendritic cells account for the majority of the class II MHC positive myeloid progeny, bone marrow CD34(+)-derived dendritic cells are less frequent than macrophages. When mature macrophages are depleted from days 5-6 cultures, terminally differentiated CD14+ HLA-DR dendritic cells as well as non-monocyte/macrophage CD14+ HLA-DR+ cells can be distinguished. The latter are post-CFU, bipotential, intermediate precursors that can terminally differentiate into either dendritic cells or macrophages depending on subsequent cytokine exposure. Human CD34+ progenitors isolated from bone marrow, as well as cord and peripheral blood, include CFU-DC that give rise to pure dendritic cell colonies in the combined presence of GM-CSF and TNF alpha. The different sources of CD34+ progenitors are not equivalent, however, with respect to frequency of CFU-DC growth. Cord blood is relatively enriched for dendritic cell progenitors. The developmental relationship of CFU-DC and CFU-GM, to the early developing dendritic cells and the bipotential intermediates observed in suspension culture, is not yet established.
在粒细胞-巨噬细胞集落刺激因子（GM-CSF）和肿瘤坏死因子α（TNFα）存在的情况下，人树突状细胞可由骨髓CD34+祖细胞生成。添加如c-kit配体这样的因子可优化树突状细胞的扩增，以及在相同条件下生长的其他髓系后代的扩增，并有助于它们的鉴定和表征。与脐带血不同，在脐带血中树突状细胞占II类主要组织相容性复合体（MHC）阳性髓系后代的大多数，而骨髓来源的CD34(+)树突状细胞比巨噬细胞少见。当从第5 - 6天的培养物中去除成熟巨噬细胞时，可区分出终末分化的CD14+ HLA-DR树突状细胞以及非单核细胞/巨噬细胞的CD14+ HLA-DR+细胞。后者是集落形成单位（CFU）后的双能中间前体细胞，根据随后的细胞因子暴露情况，可终末分化为树突状细胞或巨噬细胞。从骨髓以及脐带血和外周血中分离出的人CD34+祖细胞包括在GM-CSF和TNFα共同存在时可产生纯树突状细胞集落的CFU-DC（树突状细胞集落形成单位）。然而，就CFU-DC生长频率而言，不同来源的CD34+祖细胞并不等同。脐带血中树突状细胞祖细胞相对富集。CFU-DC和CFU-GM（粒细胞-巨噬细胞集落形成单位）与在悬浮培养中观察到的早期发育树突状细胞和双能中间体之间的发育关系尚未确定。
