TY - JOUR T1 - Systemic characterization of macrophage phenotypes in allergic airway inflammation JF - European Respiratory Journal JO - Eur Respir J VL - 44 IS - Suppl 58 SP - P1019 AU - Wilhelm Bertrams AU - Kerstin Seidel AU - Alexandra Sittka AU - Annalisa Marsico AU - Stefanie Hagner-Benes AU - Holger Garn AU - Harald Renz AU - Martin Vingron AU - Bernd Schmeck Y1 - 2014/09/01 UR - http://erj.ersjournals.com/content/44/Suppl_58/P1019.abstract N2 - Macrophages are central players in lung pathology. Besides the M1 subtype (classic activation), alternatively activated M2 macrophages have been described. Recently, microRNAs (miRNAs) have emerged as a regulatory network with great impact on cellular organization. We investigate the role of miRNAs in macrophage polarization and associated diseases. Here, we analyzed the systemic RNA phenotype of murine lung macrophages in allergic airway inflammation. We aim to compare these findings to prototypical in vitro polarized human blood-derived macrophages to assess the disease-associated polarization status in the mouse model.Different macrophage subsets were purified by FACS sorting. In vitro polarized human macrophages were isolated by CD80 (M1) or CD23 (M2) positive selection. Macrophages from the bronchoalveolar lavage fluid (BALF) and lung homogenate of mice with acute eosinophilic airway inflammation were sorted on the basis of CD11 and SiglecF. We investigated the global miRNA profile of the alveolar and interstitial macrophages by Taqman Low Density Array (TLDA). A principal component analysis (PCA) of these data was used to define the macrophage status in the lungs of healthy and asthmatic mice. Differential miRNA expression could be observed that seems to be tissue- and asthma dependent. We validated individual miRNAs that were significantly regulated in the context of asthma as determined. Up-regulation of miR-21a-5p and down-regulation of miR-126-3p, as well as down-regulation of the M1-associated miR-146a-5p was observed in interstitial macrophages. This signature suggests a M2-like polarization profile, which is in line with the TH2-skewed environment in eosinophilic airway inflammation. ER -