Fig. 1

Reduced cytokine release upon arachidonic acid challenge in COPD versus non-COPD. Pulmonary fibroblasts from COPD (n = 11–19) and non-COPD patients (n = 12–36) were unstimulated (control) or challenged with ω-6 PUFA arachidonic acid (AA) in 0.1% BSA-DMEM (10 and 100 μM) for 48 h. Cell free supernatants were collected and CXCL8 (a), IL-6 (b) and PGE2 (c) release was measured using ELISA or enzyme immunoassay. Other cells from COPD (n = 6–7) and non-COPD (n = 6–7) patients were pre-treated with indomethacin (1 μM) (d, e) or celecoxib (0.01-1 μM) (f, g) for 60 min prior to challenge with AA (100 μM) in 0.1% BSA-DMEM for 48 h. Cell free supernatants were collected and CXCL8 (d, f) and IL-6 (e, g) release was measured using ELISA. Data are expressed as mean ± standard error of the mean (a-c) or as % of AA-induced cytokine release ± standard error of the mean (d-g). Two-way ANOVA with Bonferroni post-hoc testing was used to determine statistical significance. Significance is represented as *** (p < 0.001)