@article {Yickp479, author = {C.Y. Yick and D.S. Ferreira and R. Annoni and P.W. Kunst and E.H. Bel and R. Lutter and T. Mauad and P.J. Sterk}, title = {Structure-function relationship between extracellular matrix in airway smooth muscle and dynamics of lung function in asthma}, volume = {38}, number = {Suppl 55}, elocation-id = {p479}, year = {2011}, publisher = {European Respiratory Society}, abstract = {Rationale: Asthma is characterized by an increased deposition of extracellular matrix (ECM) within the airway smooth muscle (ASM) [Panettieri 2008, Araujo 2008]. We hypothesized that ECM composition within ASM is associated with the dynamics of lung function.Aim: To investigate the fractional areas of collagen I and III within ASM, and their association with spirometry and respiratory resistance Rrs and reactance Xrs in asthmatics and controls.Methods: Atopic mild asthmatics (n=10, no ICS) and controls (n=17) were included in this cross-sectional study. Spirometry, PC20, Rrs and Xrs (forced oscillation technique during tidal breathing and deep inspiration) were measured. Paraffin sections from endobronchial biopsies were stained for collagen I and III by immunohistochemistry, and fractional areas were obtained by image analysis.Results: There was no difference in fractional areas collagen I and III within ASM between asthmatics and controls (p\>0.05). However, ASM collagen III was correlated with the change in Rrs after deep inspiration in asthmatics (r=0.74, p=0.015, Fig.1). ASM collagen I and III were not associated with spirometry or PC20.Figure 1Conclusion: These data show that collagen III composition within ASM is correlated with the dynamics of Rrs after deep inspiration in asthmatics in vivo. This suggests that ECM within ASM is positively associated with impaired airway mechanics in asthma.}, issn = {0903-1936}, URL = {https://erj.ersjournals.com/content/38/Suppl_55/p479}, eprint = {https://erj.ersjournals.com/content}, journal = {European Respiratory Journal} }