Paradigms That Define Lung Epithelial Progenitor Cell Fate in Development and Regeneration
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Purpose of Review
Throughout the lifespan, lung injury impedes the primary critical function essential for life-respiration. To repair quickly and efficiently is critical and is orchestrated by a diverse repertoire of progenitor cells and their niche. This review incorporates knowledge gained from early studies in lung epithelial morphogenesis and cell fate and explores its relevance to more recent findings of lung progenitor and stem cells in development and regeneration.
Cell fate in the lung is organized into an early specification phase and progressive differentiation phase in lung development. The advent of single-cell analysis combined with lineage analysis and projections is uncovering new functional cell types in the lung, providing a topographical atlas for progenitor cell lineage commitment during development, homeostasis, and regeneration.
Lineage commitment of lung progenitor cells is spatiotemporally regulated during development. Single-cell sequencing technologies have significantly advanced our understanding of the similarities and differences between developmental and regenerative cell fate trajectories. Subsequent unraveling of the molecular mechanisms underlying these cell fate decisions will be essential to manipulating progenitor cells for regeneration.
KeywordsLung development Progenitor cells Cell fate Lung regeneration Differentiation
Due to space limitations, we apologize to our scientific colleagues whose work could not be cited. We would like to thank Dr. Jarod Zepp for the critical review of this manuscript.
This work was supported by grants from the National Institutes of Health K08-HL140129 (D.B.F), the Parker B. Francis Foundation (D.B.F.), and the W.W. Smith Charitable Trust.
Compliance with Ethical Standards
Conflict of Interest
Aravind Sivakumar and David B. Frank declare that they have no conflict of interest
Human and Animal Rights and Informed Consent
This manuscript does not contain any original studies involving human or animal subjects.
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