Regenerative Role of Integrin Beta4pos p63pos Distal Lung Stem/Progenitor Cells

整合素 Beta4pos p63pos 远端肺干细胞/祖细胞的再生作用

• 批准号: 8717289
• 负责人: Andrew Vaughan
• 金额: $ 5.51万
• 依托单位: UNIVERSITY OF CALIFORNIA, SAN FRANCISCO
• 依托单位国家: 美国
• 财政年份: 2014
• 资助国家: 美国
• 起止时间: 2014-07-01 至 2015-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8717289
• 关键词: Address; Adopted; Alveolar; Alveolar Cell; Alveolus; Appearance; Basal Cell; Biological Process; Bleomycin; Cell model; Cells; Chronic; Chronic lung disease; Clara cell; Critical Illness; Cytokeratin; Data; Dependence; Development; Disease; Distal; Epithelial; Epithelium; Fibrosis; Future; Gases; Gene Expression Profile; Goals; Homeostasis; Human; Image; In Vitro; Individual; Influenza; Inherited; Injury; Integrins; Knowledge; Lung; Maintenance; Messenger RNA; Modeling; Molecular; Molecular Biology Techniques; Mus; Natural regeneration; Organ; Pathway interactions; Patients; Phenotype; Population; Process; Pulmonary Surfactant-Associated Protein C; Recovery; Reporting; Resolution; Role; Signal Pathway; Site; Slice; Small Interfering RNA; Source; Stem cells; Structure of parenchyma of lung; Testing; Therapeutic; Time; Tissues; Trachea; Transgenic Mice; Type II Epithelial Receptor Cell; Ursidae Family; Work; alveolar epithelium; alveolar type II cell; base; cell motility; cell type; fibrogenesis; in vivo; injured; insight; lung imaging; lung injury; lung regeneration; prevent; progenitor; public health relevance; regenerative; repaired; research study; response; stem; unpublished works

DESCRIPTION (provided by applicant): The epithelium of the distal lung performs critical biological functions including gas exchange and providing a barrier to prevent access of deleterious airborne agents into the body. It is also the target of numerous inherited and acquired diseases, represented by over 10% of the US population suffering from chronic lung disease. Despite the importance of this tissue, there is considerable disagreement as to the cell types important for the maintenance and repair of this organ. In the trachea, basal cells are the key progenitor cell type, while clara cells are thought to be more important progenitors in distal airways, especially in mice which lack basal cells outside the trachea. Alveolar type II cells have been long established as an important progenitor population for alveoli, a paradigm repeatedly confirmed in recent studies. In addition, several groups have identified cells that bear no mature lineage markers as potential progenitors for alveolar cell types. Specifically, distal lung integri ¿4-expressing cells are proposed to contribute to alveolar repair after bleomycin-induced injury, while cytokeratin 5(Krt5)/p63-expressing cells have been implicated in alveolar regeneration after influenza infection. Our unpublished work demonstrates that abundant Krt5pos cells also appear after bleomycin injury, and in both injury models these cells strongly express ¿4. Further characterization of freshly isolated ¿4+ cells from uninjured lungs revealed that these cells express p63, but not Krt5. However, upon expansion ex vivo, Krt5 is upregulated, demonstrating the propensity of these cells to adopt a basal cell-like phenotype. The major goal of this proposal is to determine whether these distal p63+ ¿4+ are in fact the cell-of-origin for expanded post-injury Krt5+ cells and to define the extent to which these cells are responsible for alveolar repair / regeneration. We will address this hypothesis with the following Specific Aims: 1) Determine the in vivo activation response of ¿4+ p63+ cells to lung injury. 2) Test whether regulated expression of p63 is critical to the acquisition of a Krt5+ regenerative phenotype by distal lung ¿4+Krt5+ cells. Several strains of transgenic mice, lung slice culture imaging, and in vitro molecular biology techniques will be used to address these aims experimentally. These studies will result in a better understanding of how lung epithelium responds to injury and will provide insights as to how lung progenitors might be exploited / directed towards therapeutic purposes.

描述（由申请人提供）：远端肺的上皮执行关键的生物学功能，包括气体交换和提供屏障以防止有害的空气传播因子进入体内。它也是许多遗传性和获得性疾病的目标，超过10%的美国人口患有慢性肺病。尽管该组织的重要性，但对于该器官的维持和修复重要的细胞类型存在相当大的分歧。在气管中，基底细胞是关键的祖细胞类型，而clara细胞被认为是远端气道中更重要的祖细胞，特别是在气管外缺乏基底细胞的小鼠中。肺泡II型细胞具有 长期以来被确立为肺泡的重要祖细胞群体，这一范例在最近的研究中反复得到证实。此外，几个研究小组已经鉴定出不携带成熟谱系标记的细胞作为肺泡细胞类型的潜在祖细胞。具体而言，远端肺整合素4表达细胞被认为有助于博来霉素诱导的损伤后的肺泡修复，而细胞角蛋白5（Krt 5）/p63表达细胞被认为与流感感染后的肺泡再生有关。我们未发表的工作表明，博来霉素损伤后也出现了丰富的Krt 5 pos细胞，并且在两种损伤模型中，这些细胞都强烈表达Krt 5 pos 4。对来自未损伤肺的新鲜分离的~ 4+细胞的进一步表征显示，这些细胞表达p63，但不表达Krt 5。然而，在离体扩增后，Krt 5被上调，表明这些细胞倾向于采用基底细胞样表型。该提议的主要目标是确定这些远端p63+<$4+是否实际上是扩增的损伤后Krt 5+细胞的起源细胞，并确定这些细胞负责肺泡修复/再生的程度。我们将通过以下具体目的来解决这一假设：1）确定p63+细胞对肺损伤的体内活化反应。2)测试p63的调节表达是否对远端肺<$4 + Krt 5+细胞获得Krt 5+再生表型至关重要。几个品系的转基因小鼠，肺切片培养成像，并在体外分子生物学技术将被用来解决这些目标的实验。这些研究将导致更好地理解肺上皮细胞如何对损伤作出反应，并将提供关于肺祖细胞如何被开发/定向用于治疗目的的见解。