Stem and Progenitor Cells of the Airway Epithelium

  • Susan D. ReynoldsEmail author
  • Moumita Ghosh
  • Heather M. Brechbuhl
  • Shama Ahmad
  • Carl W. White
Part of the Stem Cell Biology and Regenerative Medicine book series (STEMCELL)


This chapter argues that the hierarchical stem cell model should be adapted to reflect the specialized progenitor cell types that maintain the conducing airway epithelium. The conducting airway epithelium serves as the interface between the lung and the environment. Basic epithelial functions, such as barrier maintenance, are characteristic of all airway regions. However, other epithelial activities that are necessary to protect the lung from the environment vary along the proximal to distal axis of the airway. These adaptive modifications are manifest as differences in cellular composition and in the structure/function of specific cell types. Studies in humans and mice suggest that this specialization is a consequence of distinct progenitor cell pools. Each pool includes a tissue-specific stem cell and one or more facultative progenitor cell types. Facultative progenitors perform differentiated functions in the steady state but maintain the ability to proliferate in response to cellular injury. We propose that the facultative progenitor cells comprise a unique tier(s) within distinct stem cell hierarchies that maintain the proximal and distal conducing airway epithelium


Mouse Lung Clara Basal Facultative progenitor Label retention Differentiation potential 



The authors were supported by awards R01HL075585 (S.D.R.), RO1 HL075585-04S1 (S.D.R.), and RC1 HL099461 (S.D.R., C.W.W.) from the National Heart, Lung, and Blood Institute. The content is solely the responsibility of the authors and does not necessarily represent the official views of the National Heart, Lung, and Blood Institute or the National Institutes of Health. This research was also supported by a Cystic Fibrosis Foundation Research and Pilot Project grant (S.D.R.). M.G. was supported by a T32 award to the Division of Pulmonary Science and Critical Care Medicine, University of Colorado-Denver. S.A. was supported by K12 award to the University of Colorado. H.M.B. was supported by an Easton Scholarship through the Department of Pediatrics, National Jewish Health.


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Copyright information

© Springer Science+Business Media, LLC 2010

Authors and Affiliations

  • Susan D. Reynolds
    • 1
    Email author
  • Moumita Ghosh
    • 1
  • Heather M. Brechbuhl
    • 2
  • Shama Ahmad
    • 2
  • Carl W. White
    • 2
  1. 1.Division of Cell Biology, Department of PediatricsNational Jewish HealthDenverUSA
  2. 2.Department of PediatricsNational Jewish HealthDenverUSA

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