TY - JOUR T1 - 3D mapping of blood vessel networks and cells in COPD and non-COPD lung tissue samples using micro-computed tomography and immunofluorescence JF - ERJ Open Research JO - erjor DO - 10.1183/23120541.LSC-2020.21 VL - 6 IS - suppl 5 SP - 21 AU - M Lawson AU - O Katsamenis AU - M Olding AU - O Larkin AU - B Smit AU - I Haig AU - P Schneider AU - P Lackie AU - J Warner Y1 - 2020/03/05 UR - http://openres.ersjournals.com/content/6/suppl_5/21.abstract N2 - Micro-computed tomography (µCT) is a non-destructive 3D imaging technique used to map tissue microstructure at typical resolutions of 1-10 µm. Correlated with 2D immunofluorescence (IF) microscopy pathophysiologically relevant cells can be identified in 3D.We aimed to investigate 3D networks of small blood vessels (<2mm) and the distribution of immune cells in mild-moderate COPD patients.FFPE peripheral lung samples from 5 non-COPD and 5 COPD patients were scanned using µCT. IF staining for smooth muscle actin, airway epithelium, mast cells and macrophages was digitised, and co-registered with 3D µCT scans. Blood vessels, airways and infiltrating cells were identified semi-automatically by IF in the µCT volume (Fig 1).Quantitative estimates of blood vessel thickness were made, initial modal thickness values were lower in non-COPD (12-25µm) compared to COPD samples (40-60µm). Thousands of macrophages (2100-7200) and mast cells (1700-9000) were localised by IF per tissue section with fewer mast cells (<1500) detected in COPD tissue sections. Combined with the 3D vasculature network the distribution of macrophages and mast cells were found to be similar in both COPD and non-COPD with 70-80% of cells within 2mm of a blood vessel.In summary, we demonstrate an approach to identify, localise and analyse lung networks in 3D and relevant infiltrating cells in human lung disease.FootnotesCite this article as: ERJ Open Research 2020; 6: Suppl. 5, 21.This is an ERS Lung Science Conference 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 -