PT  - JOURNAL ARTICLE
AU  - yuanling liu
AU  - Xinglin Gao
AU  - Minzhen Lu
AU  - Jianan Chen
AU  - Siqi Li
TI  - Exosomes from Intermittent Hypoxia Treated Lung Adenocarcinoma Cell Line Up-regulate Programmed Death Ligand 1 Expression through HIF-1a Pathway in Macrophages
AID  - 10.1183/13993003.congress-2020.3945
DP  - 2020 Sep 07
TA  - European Respiratory Journal
PG  - 3945
VI  - 56
IP  - suppl 64
4099  - http://erj.ersjournals.com/content/56/suppl_64/3945.short
4100  - http://erj.ersjournals.com/content/56/suppl_64/3945.full
SO  - Eur Respir J2020 Sep 07; 56
AB  - Rationale: Intermittent hypoxia (IH), a hallmark of Obstructive sleep apnea (OSA), compromises immune surveillance through the upregulation of the programmed cell death-1 ligand (PD-L1). Exosomes released by cancer cells may cause immunosuppression, however, it is unknown whether IH can alter the expression of PD-L1 in macrophage by tumor-derived exosomes.Methods: Adenocarcinoma cell line A549 cells were exposed to condition of normoxia (21% O2, 5% CO2, and balance N2) or IH (48 cycles of 5 min of hypoxia [1% O2, 5% CO2 and balance N2] followed by 5 min of normoxia. Exosomes were isolated from the cell supernatant of A549 cells cultured in normoxia condition (Exo-con) or A549 cells exposed to IH (Exo-IH). Macrophages differentiated from THP-1 cells respectively were co-cultured with Exo-con, Exo-IH or Exo-IH (10 ug/ml) combined with BAY87-2243(HIF-1α inhibitor, 10μM)] and PBS for 48 hours before evaluation of PD-L1 and hypoxia-inducible factor-1(HIF-1α) expression.Result: Exosomes from IH treated A549 cells can upregulate PD-L1 and HIF-1α expression in macrophages. Specific HIF-1α inhibitor BAY87-2243 inhibited the upregulation of PD-L1 expression in the Exo-IH Group.Conclusion: Exosomes from intermittent hypoxia treated lung adenocarcinoma cell line up-regulate PD-L1 expression through HIF-1α pathway in macrophages. FootnotesCite this article as: European Respiratory Journal 2020; 56: Suppl. 64, 3945.This abstract was presented at the 2020 ERS International Congress, in session “Respiratory viruses in the "pre COVID-19" era”.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).