Impact of lung remodelling on respiratory mechanics in a model of severe allergic inflammation.
We developed a model of severe allergic inflammation and investigated the impact of airway and lung parenchyma remodelling on in vivo and in vitro respiratory mechanics. BALB/c mice were sensitized and challenged with ovalbumin in severe allergic inflammation (SA) group. The control group (C) received saline using the same protocol. Light and electron microscopy showed eosinophil and neutrophil infiltration and fibrosis in airway and lung parenchyma, mucus gland hyperplasia, and airway smooth muscle hypertrophy and hyperplasia in SA group. These morphological changes led to in vivo (resistive and viscoelastic pressures, and static elastance) and in vitro (tissue elastance and resistance) lung mechanical alterations. Airway responsiveness to methacholine was markedly enhanced in SA as compared with C group. Additionally, IL-4, IL-5, and IL-13 levels in the bronchoalveolar lavage fluid were higher in SA group. In conclusion, this model of severe allergic lung inflammation enabled us to directly assess the role of airway and lung parenchyma inflammation and remodelling on respiratory mechanics.
Laboratory of Pulmonary Investigation, Carlos Chagas Filho Biophysics Institute, Federal University of Rio de Janeiro, Centro de Ciências da Saúde, Ilha do Fundão, Rio de Janeiro, Brazil.
Pedro L
PL
Silva
Caroline P
CP
Passaro
Viviane R
VR
Cagido
Marcelo
M
Bozza
Marisa
M
Dolhnikoff
Elnara M
EM
Negri
Maina M B
MM
Morales
Vera L
VL
Capelozzi
Walter A
WA
Zin
Patricia R M
PR
Rocco
D000818:Animals; D001249:Asthma / Q000139:chemically induced / Q000473:pathology* / Q000503:physiopathology*; D004195:Disease Models, Animal; D004305:Dose-Response Relationship, Drug; D006965:Hyperplasia / Q000473:pathology; D006984:Hypertrophy / Q000473:pathology; D016210:Methacholine Chloride / Q000494:pharmacology; D051379:Mice; D008807:Mice, Inbred BALB C; D008854:Microscopy, Electron / Q000379:methods; D018721:Muscarinic Agonists / Q000494:pharmacology; D009130:Muscle, Smooth / Q000473:pathology / Q000648:ultrastructure; D010047:Ovalbumin / Q000009:adverse effects; D011650:Pulmonary Alveoli / Q000187:drug effects / Q000473:pathology / Q000648:ultrastructure; D011657:Pulmonary Eosinophilia / Q000473:pathology; D012130:Respiratory Hypersensitivity / Q000139:chemically induced / Q000473:pathology* / Q000503:physiopathology*; D015656:Respiratory Mechanics / Q000187:drug effects / Q000502:physiology*
D018721:Muscarinic Agonists; D016210:Methacholine Chloride; D010047:Ovalbumin