TY - JOUR T1 - LSC 2014 abstract - Chemerin/ChemR23 pathway in diesel exhaust particles-induced pulmonary inflammation JF - European Respiratory Journal JO - Eur Respir J VL - 44 IS - Suppl 58 SP - P1009 AU - Sharen Provoost AU - Katrien De Grove AU - Graeme Fraser AU - Kurt Tournoy AU - Guy Brusselle AU - Tania Maes AU - Guy Joos Y1 - 2014/09/01 UR - http://erj.ersjournals.com/content/44/Suppl_58/P1009.abstract N2 - Introduction: Inhalation of diesel exhaust particles (DEP) is associated with increased inflammatory reactions in the lung. We have previously shown that DEP exposure has a great impact on the monocyte-derived dendritic cell (DC) biology (Provoost, S. et al.; J Allergy Clin Immunol. 2012; 129(2): 483-91).ChemR23 is a G-protein coupled receptor that is expressed by monocytes and immature DC. Its ligand, chemerin, is secreted by the epithelium as an inactive precursor (prochemerin) which is converted by neutrophil proteases into bioactive chemerin.Here, we investigated whether the Chemerin/ChemR23 axis is involved in the DEP-induced DC modulation and inflammation.Methods: Wild type (WT) and ChemR23 knock out (KO) mice were intratracheally instilled with saline or 100 µg DEP on day 1, 4 and 7. On day 9, we assessed the DEP-induced chemerin expression and inflammatory response in bronchoalveolar lavage (BAL) and lung tissue.Results: Exposure to DEP decreased the (pro-)chemerin staining in airway epithelial cells. This was associated with elevated (pro-)chemerin levels in BAL, suggesting an increased release of chemerin upon DEP exposure.In chemR23 KO mice, DEP-induced monocyte and monocyte-derived DC recruitment was greatly attenuated in the BAL and lung tissue when compared with WT mice. In contrast, the numbers of conventional DC in lung tissue and alveolar DC were similar between DEP-exposed chemR23 KO and WT mice.Conclusions: These data suggest that the chemerin/ChemR23 axis is involved in the DEP-induced monocyte-derived DC recruitment.Funding: FWO Vlaanderen; Belgian IUAP P7/30; Concerted Research Initiative – Ghent University. ER -