TY - JOUR T1 - Aberrant intracellular expression of laminin α-2 and -5 in bronchiolar epithelium of COPD patients JF - European Respiratory Journal JO - Eur Respir J VL - 44 IS - Suppl 58 SP - P3955 AU - Oskar Johansson AU - Jonas Erjefält AU - Leif Bjermer AU - Claes-Göran Löfdahl AU - Gunilla Westergren-Thorsson AU - Oskar Hallgren Y1 - 2014/09/01 UR - http://erj.ersjournals.com/content/44/Suppl_58/P3955.abstract N2 - Laminins constitute fundamental building blocks of basement membranes and have been shown to influence cell behaviour in a laminin-subunit specific manner. One such example is that immune cell diapedesis is facilitated by laminin α-4 compared to laminin α-5. Although changes in laminin expression have been observed in COPD, more in depth studies is needed to unravel the pathophysiological implications of these alterations. This study aimed to examine the abundance and distribution of specific laminin subunits in COPD. Laminin α-2 and α-5 expression were evaluated with immunohistochemistry in peripheral lung tissue from COPD patients (GOLD I-IV), smoker and non-smoker controls.Immunoreactivity for laminin α-5 was found in basal membranes underlying bronchiolar epithelium and endothelium in peribronchiolar blood vessels. Bronchiolar epithelium was found to show a prominent intracellular immunoreactivity for laminin α-5 in COPD-afflicted lungs, in stark contrast to control lung epithelium which lacked this immunoreactivity pattern. Intracellular immunoreactivity was restricted to well-delimited subcellular compartments overlying the nucleus on the luminal side of the columnar epithelial cell. Laminin α-2 were not found in basal membranes of neither control nor COPD lung, while showing an intracellular immunoreactivity pattern similar to that of laminin α-5 in the bronchiolar epithelium of COPD-patients.Our data indicate that COPD pathology is associated with specific changes in expression patterns of laminin α-2 and α-5. Disruption of tissue homeostasis regarding laminin expression might contribute to chronic inflammation and a process of ongoing extracellular matrix remodelling. ER -