REGULATION OF HUMAN HEMATOPOIETIC STEM CELL CYCLE INDUCTION

该项目的目标是确定诱导原始的、静止的人类造血干细胞（HSC）进入细胞周期的方法，并确定在体外和体内发生的相关表型和分子变化。在免疫缺陷小鼠体内和体外，我们将对CD45+/CD34+/lin-和CD45+/CD34-/lin细胞的细胞周期诱导进行评估。长期移植米色/裸色/黄色（bnx）小鼠细胞表面CD34的骨髓恢复。我们推测，移植到bnx小鼠骨髓中的人造血干细胞在体内亚致死照射后，会因人干细胞的激活而丢失。我们已经证明，亚致死照射导致免疫缺陷小鼠骨髓微环境中人CD34+细胞数量增加。我们假设来自亚致死照射细胞的诱导信号将导致CD34+/lin-和CD34 -/lin-细胞的细胞周期诱导。我们将使用植入bnx和NOD/SCID小鼠的人类干细胞来验证这一假设。我们之前已经证明，这种水平的降低现在扩展了这些研究，以确定在体外诱导人类CD34-/lin-干细胞进入细胞周期的方法，以促进个体人类CD34+/lin-和CD34-/lin-细胞是否可以在体外转导，并保留在体外产生多系造血的能力。利用我们开发的CD34+/lin和CD34-/lin- pcr方法追踪个体标记的人类HSC。计划中的研究将建立体内相关性。促进两种类型干细胞快速细胞周期进入和转导的人类技术之间的关系，并将证明哪一种造血谱系可以从来自每个群体的单个转导的干细胞中获得。

The goals of this project are to define methods to induce primitive, quiescent human hematopoietic stem cells (HSC) to enter cell cycle, and to determine the associated phenotyping and molecular changes that occur in vitro and in vivo. Cell cycle induction of both CD45+/CD34+/lin- and CD45+/CD34-/lin cells will be evaluated in side-by-side comparisons in vitro and in vivo in immune deficient mice. Bone marrow recovered from long-term engrafted beige/nude/xid (bnx) mice CD34 at the cell surface. We hypothesize that the human HSC engrafted in the bone marrow of bnx mice lose by activation of the human stem cells in vivo, following sublethal irradiation of the mice. We have demonstrated that sublethal irradiation leads to an increase in the number of human CD34+ cells in the marrow of immune deficient murine marrow microenvironment. We hypothesize that the inductive signals from the sublethally irradiated cells and will result in cell cycle induction in both CD34+/lin- and Cd34-/lin- cells We will use human stem cells engrafted in bnx and NOD/SCID mice to test this hypothesis. We have previously demonstrated that reduction that reduction in levels now extend those studies to define in vitro methods to induce cell cycle entry in human CD34-/lin-stem cells, to facilitate whether individual human CD34+/lin- and CD34-/lin- cells can be transduced in vitro and retain the capacity to give rise to multi-lineage hematopoiesis in vitro. Tracking of individual, marked human HSC from the CD34+/lin and CD34-/lin-PCR method that we developed. The planned studies will establish an in vivo correlation. between human techniques to promote rapid cell cycle entry and transduction of both types of stem cells, and will demonstrate which hematopoietic lineages can be derived from individual, transduced stem cells from each population.