TY - JOUR T1 - Exhausted T lymphocytes in chronic obstructive pulmonary disease: single-cell analysis of human lung tissue JF - European Respiratory Journal JO - Eur Respir J DO - 10.1183/13993003.congress-2021.PA870 VL - 58 IS - suppl 65 SP - PA870 AU - Sun Hye Shin AU - Kyu-Tae Kim AU - Kyung Yeon Han AU - Jiseon Kim AU - Donghyun Park AU - Na Hyun Kim AU - Chang-Ho Shon AU - Jin-Young Huh AU - Sei Won Lee AU - Hye Yun Park Y1 - 2021/09/05 UR - http://erj.ersjournals.com/content/58/suppl_65/PA870.abstract N2 - Introduction: Emerging evidence suggests that chronic obstructive pulmonary disease (COPD) patients have increased CD8+ T cells in their lungs and these T cells show increased expression of exhausted markers, using flow cytometry. This study aimed to confirm the increased level of exhausted CD8+ T cells in lung tissue of COPD patients, by using single-cell analysis.Methods: We prospectively recruited 22 COPD patients (grade 1, n =9; grade 2, n = 13) and 10 non-COPD patients with non-small cell lung cancer undergoing surgical resection. Non-tumor adjacent lung tissues were obtained and dissected into single cells. Single-cell RNA sequencing was performed to determine the heterogeneity of CD8+ T cell between patients with and without COPD.Results: Gene-expression profiles of 127,844 cells were clustered and annotated by established marker genes. We next explored the dynamic immune states and cell transitions in CD8+ T cells by inferring the state trajectories, and could finally reach an exhausted state. We also determined the proportion of exhausted T cells according to smoking exposure and COPD patients with grade 2 showed a significant association between smoking burden and increased level of exhausted T cells. Furthermore, we observed a greater ratio of progenitor-like exhausted T cells in COPD patients with grade 2 in comparison with non-COPD and COPD patients with grade 1.Conclusion: In COPD patients with moderate severity, increased level of exhausted T cell was associated with smoking burden, while those exhausted T cells were more likely to be potentially reverted.FootnotesCite this article as: European Respiratory Journal 2021; 58: Suppl. 65, PA870.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 -