Myofibroblasts are increased in the lung parenchyma in asthma.
Ontology highlight
ABSTRACT: Background
Increased airway smooth muscle is observed in large and small airways in asthma. Semi-quantitative estimates suggest that cells containing alpha smooth muscle actin (?-SMA) are also increased in the lung parenchyma. This study quantified and characterized ?-SMA positive cells (?-SMA+) in the lung parenchyma of non-asthmatic and asthmatic individuals.Methods
Post-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 ?-SMA, quantified using point-counting and normalised to alveolar basement membrane length and interstitial area.Results
?-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 < 0.05 The difference was greater in upper lobes compared with lower lobes (p < 0.01) in both asthma groups. Similar changes were observed in alveolar ducts and alveolar walls. The electron microscopic features of the ?-SMA+ cells were characteristic of myofibroblasts.Conclusions
We conclude that in asthma there is a marked increase in ?-SMA+ myofibroblasts in the lung parenchyma. The physiologic consequences of this increase are unknown.
SUBMITTER: Boser SR
PROVIDER: S-EPMC5546673 | biostudies-literature | 2017
REPOSITORIES: biostudies-literature
Publications
Myofibroblasts are increased in the lung parenchyma in asthma.
Boser Stacey R SR Mauad Thais T Araújo-Paulino Bianca Bergamo de BB Mitchell Ian I Shrestha Grishma G Chiu Andrea A Butt John J Kelly Margaret M MM Caldini Elia E James Alan A Green Francis H Y FHY
PloS one 20170807 8
<h4>Background</h4>Increased 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.<h4>Methods</h4>Post-mortem sections of peripheral lung from cases of fatal asthma (FA), persons with asthma dying of non-respira ...[more]
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