Identification of Tissue Specific Stem Cells

我们的具体目标是继续探索干细胞的生物学。特定目标1使用简化的渐变 分离以分离干细胞。我们计划进行研究，根据功能特征分离干细胞。 我们认为，最原始的静止干细胞可能不表达可归因于 长期移植细胞。我们有证据表明多潜能干细胞可以增殖和分化。 分化成不同胚层的细胞。我们计划进行额外的克隆分析来评估细胞的植入能力。 纯干细胞群体。我们将检查非造血细胞(上皮)植入我们的富集物 骨髓来源的干细胞群体。我们计划研究已知的调节 小鼠成体和胚胎干细胞群体的增殖和分化。最后，在具体目标上 1，我们将确定通过梯度分离技术分离的干细胞是否具有转化能力 作为对损伤信号的反应，骨髓细胞进入上皮组织。在第二个目标中，重要的是，我们将 试图区分组织特异性干细胞的存在和多能性的存在 驻留在骨髓中的干细胞，当受到外部损伤信号刺激时，将通过 动员到损伤部位，转化为新的细菌层，并帮助修复损伤。 相关性 骨髓移植已被用于治疗血液系统衰竭或恶性疾病，并日益增多。 成功。最近的动物模型和一些临床试验已经使用干细胞群体通过 移植。我们正在尝试定义可用于这种修复的细胞类型，开发简单的 以及分离这些细胞并确定微环境中的哪些因素的通用方法 负责干细胞的自我更新和分化。

Our Specific aims continue to explore the biology of stem cells. Specific aim 1 uses simplified gradient separation to isolate stem cells. We plan studies which will isolate stem cells by functional characteristics. We believe that the most primitive quiescent stem cell may not express cell surface antigens attributable to long term engrafting cells. We have evidence that mul tipotential stem cells can proliferate and differentiate into cells of different germ layers. We plan additional clonal a nalysis to evaluate the engraftment capacity of pure stem cell populations. We will examine the nonhematopoieitc (epithelial) engraftment of our enriched populations of marrow derived stem cells. We plan to examine the factors which are known to regulate the proliferation and differentiation of mouse adult and embryonic stem cell populations. Finally, in specific aim 1, we will determine if stem cells isolated by gradient separation technology have the capacity to convert marrow cells into epithelial tissues in response to injury signals. In the second aim, importantly, we will attempt to distinguish between the presence of tissue specific stem cells and the existence of a pluripotent stem cell which resides in the bone marrow which, when stimulated by external injury signals, will respond by mobilization to the site of injury, convert into a new germ layer, and aid in repair of the injury. Relevance Bone marrow transplantation has been utilized for hematological failure or malignancy with increasing success. Recent animal models and a few clinical trials have used stem cell populations to repair injury via transplantation. We are attempting to define the cell types which can be used for such repair, develop simple and universal methods for isolating those cells and determining what factors in the microenvironment are responsible for stem cell self renewal and differentiation.