Murine hematopoietic stem cells change their surface phenotype during ex vivo expansion
Murine hematopoietic stem cells change their surface phenotype during ex vivo expansion
复制标题
DOI：
10.1182/blood-2004-11-4418
复制
发表时间：
2005-06-01
期刊：
影响因子：
20.3
通讯作者：
Lodish, HF
中科院分区：
文献类型：
--
作者：
Zhang, CC;Lodish, HF
造血干细胞（hsc）的体外扩增对许多临床应用都很重要，了解体外扩增的造血干细胞的表面表型对其纯化和分析至关重要。在这里，我们开发了一种简单的骨髓造血干细胞培养系统，在无血清培养基中使用低水平的干细胞因子（SCF）、血小板生成素（TPO）、胰岛素样生长因子2 （IGF-2）和成纤维细胞生长因子-1 （FGF-1）。通过竞争性再种群分析，在总BM细胞培养10天后，长期(LT)- hsc的数量增加了20倍以上。BM“侧群”（SP）细胞（一种高度富集的干细胞群）培养10天后，再生的hsc扩增了大约8倍。与新鲜分离的造血干细胞类似，培养后重新填充的造血干细胞对干细胞标记物Sca-1、Kit和CD31以及IGF-2受体呈阳性。令人惊讶的是，新分离的造血干细胞中存在的朊蛋白和Tie-2在培养的造血干细胞中没有。另外两种HSC标志物，Endoglin和Mpl仅在部分培养的HSC上表达。因此，体外扩增的造血干细胞表面表型与新鲜分离的造血干细胞不同，但这种表面表型的可塑性并没有显著改变其再种群能力。
Ex vivo expansion of hematopoietic stem cells (HSCs) is important for many clinical applications, and knowledge of the surface phenotype of ex vivo-expanded HSCs will be critical to their purification and analysis. Here, we developed a simple culture system for bone marrow (BM) HSCs using low levels of stem cell factor (SCF), thrombopoietin (TPO), insulin-like growth factor 2 (IGF-2), and fibroblast growth factor-1 (FGF-1) in serum-free medium. As measured by competitive re-population analyses, there was a more than 20-fold increase in numbers of long-term (LT)-HSCs after a 10-day culture of total BM cells. Culture of BM "side population" (SP) cells, a highly enriched stem cell population, for 10 days resulted in an approximate 8-fold expansion of repopulating HSCs. Similar to freshly isolated HSCs, repopulating HSCs after culture were positive for the stem cell markers Sca-1, Kit, and CD31 and receptors for IGF-2. Surprisingly, prion protein and Tie-2, which are present on freshly isolated HSCs, were not on cultured HSCs. Two other HSC markers, Endoglin and Mpl, were expressed only on a portion of cultured HSCs. Therefore, the surface phenotype of ex vivo-expanded HSCs is different from that of freshly isolated HSCs, but this plasticity of surface phenotype does not significantly alter their re-population capability.