FIGURE 7.

Expression of resistin-like molecule-α (RELMα) is restricted to epithelial cells located in the areas of fibrosis. UMAP: uniform manifold approximation and projection; SPC: surfactant protein C. a) UMAP plot demonstrating subclusters of alveolar type II cells. b) UMAP plot and c) bar plot demonstrating composition of the alveolar type II cell subclusters. d) Feature plot demonstrating increased expression of Retnla in alveolar type II cells 14 days after asbestos exposure. e) Cx3cr1^ER-Cre×ZsGreen mice were administered with asbestos intratracheally and treated with tamoxifen at days 14 and 15 after exposure; lungs were harvested for analysis at day 21. Representative fluorescent images showing expression of RELMα (red), SPC (blue) and CX3CR1–green fluorescent protein (green) in lungs from TiO₂- or asbestos-treated animals at day 21 post-exposure. RELMα is detected in the airway epithelial cells and alveolar type II cells in the fibrotic regions in the asbestos model, but not in alveolar type II cells after TiO₂ exposure. Scale bar: 100 µm. f) Enlargement of the box in (e): RELMα-positive epithelial cells (red) and monocyte-derived alveolar macrophages (green) are co-localised with asbestos fibres. Experimental design same as in (e).