Melanocyte Stem Cells in Regenerative Medicine

描述(由申请人提供)： 这项拟议的研究旨在确定我们已经鉴定的黑素细胞干细胞(MSCs)的不同亚群如何在干细胞状态下被调节和维持，并对神经沟来源的细胞再生做出贡献。这项研究的基本原理是基于我们的发现，间充质干细胞不仅分布在小鼠毛囊(HF)中称为隆起的区域，也是毛囊的角质形成干细胞(KcSCs)的位置，而且还存在于次级毛胚(SHG)，这是一种位于毛乳头附近的端原或静止毛囊的临时结构。我们的实验室已经开发出结合独特的转基因小鼠系统和荧光激活细胞分类(FACS)的方法来分离和研究这两个存活状态的细胞亚群。我们研究的目的是发现这些干细胞亚群的特异性标记，并确定小鼠的CD34+MSCs和它们的细胞类似物是否可以再生功能强大的胶质细胞和神经细胞，正如初步数据所表明的那样。我们还将在体外和体内确定CD34+MSC亚群与CD34-MSCs相比显示出更大的发育潜力，是否可以再生神经嵴来源的神经胶质细胞和神经细胞。从小鼠实验中获得的信息将被用于从人类皮肤中识别可比的干细胞群体。这些研究将由我们开发的独特的双转基因小鼠品系DCT-H2BGFPki与FACS设施和其他核心资源相结合来完成，这些资源与我位于马里兰大学医学院生物化学和分子生物学系的研究实验室相关。这些研究的结果应该会对退伍军人的医疗保健产生积极的影响。我们发现CD34+MSC亚群选择性地表达神经胶质和神经元标记，这可能为使用从人类皮肤轻松获得的细胞来支持退伍军人从神经损伤和神经退行性疾病中恢复提供一种策略。

DESCRIPTION (provided by applicant): The proposed study is designed to determine how distinct subsets of melanocyte stem cells (MSCs) we have identified are regulated and maintained in the stem cell state and contribute to neural crest-derived cell regeneration. The rationale for the study is based upon our discovery that MSCs not only populate a region of the murine hair follicle (HF) termed the bulge, also the site of keratinocyte stem cells (KcSCs) of the HF, but also the secondary hair germ (SHG), a transient structure at the base of the telogen, or resting, HF adjacent to the dermal papilla. Our laboratory has developed methods to separate and study these two cell subsets in the viable state using a combination of a unique transgenic mouse system and fluorescence-activated cell sorting (FACS).The objectives of our studies are to discover specific markers of these stem cell subsets and to determine whether CD34+ MSCs in mice, and their cellular analogs in humans, can regenerate functional glial and neuronal cells, as suggested by preliminary data. We will also determine both in vitro and in vivo whether the CD34+ MSC subset, which exhibits an expanded developmental potential compared to CD34- MSCs, can regenerate neural crest- derived glial and neuronal cells. Information obtained from murine experiments will be used to identify comparable stem cell populations from human skin. These studies will be accomplished a unique, bitransgenic mouse line we have developed, Dct-H2BGFPki, in combination with the FACS facility and other core resources associated with my research laboratory located in the Department of Biochemistry and Molecular Biology at the University of Maryland School of Medicine. The results of these studies should have a positive impact on the health care of Veterans. Our discovery that the CD34+ MSC subset selectively expresses glial and neuronal markers may provide a strategy for using cells easily obtained from human skin to be used to support Veteran recovery from neurological injury and neurodegenerative disease.