造血干细胞生物学——研究与展望

造血干细胞（hematopoietic stem cell，HSC）是目前研究方法最为多样、研究技术手段最为成熟的一类组织干细胞，并且已经被成功运用于临床上对白血病以及先天性免疫缺陷等疾病的治疗。近年来，通过对一系列“转基因”与“基因敲除”小鼠模型的分析，人们对造血干细胞在胚胎早期发育过程中的发生与起源、造血干细胞“自我更新”与“定向分化”的调节机制、骨髓中造血干细胞的微环境（niche）对造血干细胞功能维持的调控，以及造血干细胞与白血病干细胞之间的相互关系等诸多方面都取得了很大的进展。如何实现造血干细胞的体外长期培养与扩增，实现胚胎干细胞（embryonic stem cell，ESC）或诱导多能干细胞（induced pluripotent stem cell，iPS细胞）向造血干细胞进行有效的定向分化，以及探索造血干细胞在病理状态（如癌症、贫血、衰老等）或应激状态下（如炎症与感染、组织损伤、代谢异常等）的功能变化，都将会是今后造血干细胞研究的重要方向。

The biology of hematopoietic stem cells---recent advances and future

The hematopoietic stem cell （HSC） is one of the best-characterized tissue stem cell and has been successfully applied in clinical application in the treatment of diseases such as leukemia and congenital immunodeficiencies. Recent studies using a number of transgenic and gene-targeted mouse models have begun to unveil the origin of HSC during early embryogenesis, and the key cell-intrinsic regulators and the extrinsic signals from the bone marrow niches that control HSC self-renewal and lineage commitment, as well as the relationship of normal HSC and leukemic stem cells. Future studies will focus on optimizing the ex vivo culture conditions for HSC and direct differentiation of hES/iPS into HSC, and HSC responses to pathological or stressful conditions.