Lung Biology Group, Regenerative Medicine Institute, National Centre for Biomedical Engineering Science, National University of Ireland, University Road, Galway, Ireland.
Stem Cell Res Ther. 2011 Oct 20;2(5):41. doi: 10.1186/scrt82.
The ideal cell type to regenerate an acutely injured or chronically diseased lung would be a stem cell population from the patient's own lung. Consequently, extensive research efforts have focused on identifying and characterizing endogenous lung stem cells. Advances in techniques to facilitate cell isolation, labelling and tracking in vivo to determine their fate have led to the identification of several putative stem cell niches. Recently, convincing evidence has emerged for a novel stem/progenitor cell population in the submucous glands of the cartilaginous airways. These findings support the concept that there is no classical stem cell 'hierarchy' but that different progenitor populations within spatially distinct lung regions regenerate the lung epithelium adjacent to its niche. Intriguingly, recent findings challenge this concept; it was reported that the human lung may contain a primitive stem cell capable of differentiating into multiple cells of both endodermal and mesodermal lineage and of regenerating the injured lung. This suggests that a classical stem cell hierarchy may, in fact, exist in the lung. Although caution is needed in interpreting these emerging findings, the implications for our current concepts regarding lung stem cells, the insights into lung repair and regeneration, and the potential therapeutic implications are considerable.
理想的用于再生急性损伤或慢性疾病肺部的细胞类型将是来自患者自身肺部的干细胞群体。因此，大量的研究工作集中在鉴定和描述内源性肺干细胞上。为了确定它们的命运，促进细胞分离、标记和体内跟踪的技术的进步已经导致了几个假定的干细胞龛的识别。最近，在软骨气道的粘膜下腺中出现了一种新型的干细胞/祖细胞群体的令人信服的证据。这些发现支持这样一种概念，即没有经典的干细胞“等级”，而是不同的祖细胞群体在空间上不同的肺区域中再生邻近其龛的肺上皮。有趣的是，最近的发现挑战了这一概念；据报道，人类肺部可能含有一种原始的干细胞，能够分化为内胚层和中胚层谱系的多种细胞，并能再生受损的肺部。这表明在肺部实际上可能存在经典的干细胞等级。尽管在解释这些新出现的发现时需要谨慎，但这些发现对我们目前关于肺干细胞的概念、对肺修复和再生的深入了解以及潜在的治疗意义都具有重要意义。
