Zijlmans J M, Visser J W, Laterveer L, Kleiverda K, Heemskerk D P, Kluin P M, Willemze R, Fibbe W E
Department of Hematology, Leiden University Medical Center, The Netherlands.
Proc Natl Acad Sci U S A. 1998 Jan 20;95(2):725-9. doi: 10.1073/pnas.95.2.725.
Blood cells transplantation is largely replacing bone marrow transplantation because engraftment is more rapid. This accelerated engraftment is thought to be mediated by relatively mature committed hematopoietic progenitor cells. Herein, we have used a modified rhodamine (Rho) staining procedure to identify and purify Rho+/++ (dull/bright) and Rho- (negative) subpopulations of hematopoietic progenitor cells in murine cytokine-mobilized blood. The Rho+/++ cell population contained > 99% of committed progenitor cells with in vitro colony-forming ability. The Rho- cell population contained the majority of hematopoietic stem cells with in vivo marrow repopulating ability. The rate of hematopoietic reconstitution was identical in recipients of grafts containing only purified Rho- stem cells or purified Rho- stem cells in combination with large numbers of Rho+/++ committed progenitor cells. In contrast, transplantation of 3-fold more hematopoietic stem cells resulted in accelerated reconstitution, indicating that the reconstitution rate was determined by the absolute numbers of Rho- stem cells in the graft. In addition, we observed a 5- to 8-fold reduced frequency of the subset of hematopoietic stem cells with long-term repopulating ability in cytokine-mobilized blood in comparison to steady-state bone marrow. Our results indicate that hematopoietic stem cells and not committed progenitor cells mediate early hematopoietic reconstitution after blood cell transplantation and that relative to bone marrow, the frequency of stem cells with long-term repopulating ability is reduced in mobilized blood.
由于植入更快，血细胞移植正在很大程度上取代骨髓移植。这种加速植入被认为是由相对成熟的定向造血祖细胞介导的。在此，我们使用了一种改良的罗丹明（Rho）染色程序来鉴定和纯化小鼠细胞因子动员血液中造血祖细胞的Rho+/++（暗淡/明亮）和Rho-（阴性）亚群。Rho+/++细胞群包含>99%具有体外集落形成能力的定向祖细胞。Rho-细胞群包含大多数具有体内骨髓重建能力的造血干细胞。在接受仅含有纯化的Rho-干细胞或纯化的Rho-干细胞与大量Rho+/++定向祖细胞组合的移植物的受体中，造血重建速率是相同的。相比之下，移植多3倍的造血干细胞导致重建加速，这表明重建速率由移植物中Rho-干细胞的绝对数量决定。此外，我们观察到与稳态骨髓相比，细胞因子动员血液中具有长期重建能力的造血干细胞亚群的频率降低了5至8倍。我们的结果表明，造血干细胞而非定向祖细胞介导血细胞移植后的早期造血重建，并且相对于骨髓，动员血液中具有长期重建能力的干细胞频率降低。
