TY - JOUR T1 - Human dendritic cells with PD-1+ CD80+ expression from lymph nodes aspirates of sarcoidosis patients JF - European Respiratory Journal JO - Eur Respir J DO - 10.1183/13993003.congress-2021.PA697 VL - 58 IS - suppl 65 SP - PA697 AU - Elżbieta Rutkowska AU - Iwona Kwiecień AU - Rafał Sokołowski AU - Joanna Bednarek AU - Agata Raniszewska AU - Karina Jahnz-Różyk AU - Piotr Rzepecki Y1 - 2021/09/05 UR - http://erj.ersjournals.com/content/58/suppl_65/PA697.abstract N2 - Sarcoidosis (SA) is a systemic granulomatous disorder of unknown etiology, mediastinal lymph nodes (LNs) are the main location. Dendritic cells (DCs) play a pivotal role in homeostasis of the immune system and may play role as integral players in sarcoidosis pathogenesis, but still little is known about the expression of immunosuppressive molecules on these cells and using them as potential therapeutic targets. The immunomodulatory properties of DC in sarcoidosis seem to be interesting.The aim of this study was to determine the DCs subsets and with expression of immunomodulating and costimulatory molecules: PD-1, PD-L1 and CD80 in LNs aspirates and peripheral blood PB in patients with pulmonary SA.LNs aspirates were obtained during EBUS/TBNA procedure of 10 patients with SA. The cells were analysed by flow cytometry.We reported the higher percentage of DCs in EBUS than in PB (0.203% vs 0.113% p<0.05). The conventional and plasmacytoid DCs (pDCs) were not different. pDCs were the dominant population in both EBUS and PB. The proportions of PD-1 and CD80 DCs were higher in EBUS than PB (respectively 7.0% vs 2.8% and 9.9% vs 2.9%, p< 0.05). The proportion of immature DCs (imDCs) and regulatory DCc (DCregs) were not different between EBUS and PB.These findings suggest that the DCs may migrate from PB into the lymph nodes in SA patients. We report for the first time that DCs in EBUS show increased expression of inhibitory molecule: PD-1 and stimulatory CD80, possibly contributing to the regulation of the inflammation.FootnotesCite this article as: European Respiratory Journal 2021; 58: Suppl. 65, PA697.This abstract was presented at the 2021 ERS International Congress, in session “Prediction of exacerbations in patients with COPD”.This is an ERS International Congress abstract. No full-text version is available. Further material to accompany this abstract may be available at www.ers-education.org (ERS member access only). ER -