PLoS ONE (Jan 2017)

Myofibroblasts are increased in the lung parenchyma in asthma.

  • Stacey R Boser,
  • Thais Mauad,
  • Bianca Bergamo de Araújo-Paulino,
  • Ian Mitchell,
  • Grishma Shrestha,
  • Andrea Chiu,
  • John Butt,
  • Margaret M Kelly,
  • Elia Caldini,
  • Alan James,
  • Francis H Y Green

DOI
https://doi.org/10.1371/journal.pone.0182378
Journal volume & issue
Vol. 12, no. 8
p. e0182378

Abstract

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BackgroundIncreased airway smooth muscle is observed in large and small airways in asthma. Semi-quantitative estimates suggest that cells containing alpha smooth muscle actin (α-SMA) are also increased in the lung parenchyma. This study quantified and characterized α-SMA positive cells (α-SMA+) in the lung parenchyma of non-asthmatic and asthmatic individuals.MethodsPost-mortem sections of peripheral lung from cases of fatal asthma (FA), persons with asthma dying of non-respiratory causes (NFA) and non-asthma control subjects (NAC) were stained for α-SMA, quantified using point-counting and normalised to alveolar basement membrane length and interstitial area.Resultsα-SMA+ fractional area was increased in alveolar parenchyma in both FA (14.7 ± 2.8% of tissue area) and NFA (13.0 ± 1.2%), compared with NAC (7.4 ± 2.4%), p ConclusionsWe conclude that in asthma there is a marked increase in α-SMA+ myofibroblasts in the lung parenchyma. The physiologic consequences of this increase are unknown.