Department of Genetic Medicine, Weill Cornell Medical College, New York, NY 10065, USA.
Blood. 2012 Aug 9;120(6):1344-7. doi: 10.1182/blood-2011-12-398115. Epub 2012 Jun 18.
Transplantation of ex vivo expanded human umbilical cord blood cells (hCB) only partially enhances the hematopoietic recovery after myelosuppressive therapy. Incubation of hCB with optimal combinations of cytokines and niche cells, such as endothelial cells (ECs), could augment the efficiency of hCB expansion. We have devised an approach to cultivate primary human ECs (hECs) in serum-free culture conditions. We demonstrate that coculture of CD34(+) hCB in direct cellular contact with hECs and minimal concentrations of thrombopoietin/Kit-ligand/Flt3-ligand resulted in a 400-fold expansion of total hematopoietic cells, 150-fold expansion of CD45(+)CD34(+) progenitor cells, and 23-fold expansion of CD45(+) Lin(-)CD34(hi+)CD45RA(-)CD49f(+) stem and progenitor cells over a 12-day period. Compared with cytokines alone, coculture of hCB with hECs permitted greater expansion of cells capable of multilineage engraftment and serial transplantation, hallmarks of long-term repopulating hematopoietic stem cells. Therefore, hECs establish a cellular platform for expansion of hematopoietic stem and progenitor cells and treatment of hematologic disorders.
体外扩增的人脐带血细胞（hCB）移植仅能部分增强骨髓抑制治疗后的造血恢复。用最佳组合的细胞因子和龛细胞（如内皮细胞（ECs））孵育 hCB，可以提高 hCB 扩增的效率。我们设计了一种在无血清培养条件下培养原代人 ECs（hECs）的方法。我们证明，CD34(+) hCB 与 hECs 直接细胞接触，并在最低浓度的血小板生成素/Kit 配体/Flt3 配体存在的情况下共培养，可使总造血细胞扩增 400 倍，CD45(+)CD34(+)祖细胞扩增 150 倍，CD45(+)Lin(-)CD34(hi+)CD45RA(-)CD49f(+)干细胞和祖细胞扩增 23 倍，共 12 天。与细胞因子单独培养相比，hCB 与 hECs 共培养可使能够多谱系植入和连续移植的细胞（长期重建造血干细胞的标志）得到更大程度的扩增。因此，hECs 为造血干细胞和祖细胞的扩增以及血液疾病的治疗建立了一个细胞平台。
