Punzel M, Ho A D
Medizinische Poliklinik, University of Heidelberg, Hospital Str. 3, 69115 Heidelberg, Germany.
Ann N Y Acad Sci. 2001 Jun;938:72-81; discussion 81-2. doi: 10.1111/j.1749-6632.2001.tb03576.x.
To maintain self-renewal and multilineage differentiation capacity, hematopoietic stem cell (HSC) proliferation requires both symmetric and asymmetric cell divisions. We have applied a time-lapse camera system and our single-cell culture to correlate early replication behavior with short- and long-term function. Using five-dimensional flow cytometry to purify subpopulations of fetal liver (FLV), fetal bone marrow (FBM), umbilical cord blood (UCB), adult bone marrow (ABM), and mobilized peripheral blood (MPB), we studied the relationship between colony efficiency (CE) growth pattern and ontogenic age. The highest CE was found among HSC candidates from FLV, FBM, and UCB and the lowest from ABM. Relating the divisional behavior with functional readouts, we demonstrated that although mitotic rate, colony efficiency, and percent of asymmetric divisions all decreased with ontogenic age, the fraction of cells undergoing asymmetric divisions was consistently at 45%. After 10 days of culture, 60.6 +/- 9.8% of the PKH bright cells gave rise to colonies (15.8 +/- 7.8% dispersed) compared to 15.9 +/- 11.1% of the PKH dim cells (2.5 +/- 2.5% dispersed). In addition, the much more primitive Myeloid-Lymphoid Initiating Cells (ML-IC) are predominantly found in the PKH-bright population. Thus, primitive function of individual candidate HSCs closely related to their divisional behavior.
为维持自我更新和多谱系分化能力，造血干细胞（HSC）增殖需要对称和不对称细胞分裂。我们应用了延时摄像系统和单细胞培养方法，将早期复制行为与短期和长期功能相关联。使用五维流式细胞术纯化胎儿肝脏（FLV）、胎儿骨髓（FBM）、脐带血（UCB）、成人骨髓（ABM）和动员外周血（MPB）的亚群，我们研究了集落效率（CE）生长模式与个体发育年龄之间的关系。在来自FLV、FBM和UCB的HSC候选细胞中发现最高的CE，而在ABM中最低。将分裂行为与功能读数相关联，我们证明，尽管有丝分裂率、集落效率和不对称分裂百分比均随个体发育年龄而降低，但经历不对称分裂的细胞比例始终为45%。培养10天后，60.6±9.8%的PKH亮细胞形成集落（15.8±7.8%分散），而PKH暗细胞为15.9±11.1%（2.5±2.5%分散）。此外，更为原始的髓系-淋巴系起始细胞（ML-IC）主要存在于PKH亮群体中。因此，单个候选HSC的原始功能与其分裂行为密切相关。
