PTAFR and idiopathic pulmonary fibrosis: PAFR and ICAM–1 positive expression in small airways (SA) epithelium and lung parenchyma in IPF and NC are shown in Figure 1A and Figure 2B. PAFR and ICAM–1 were showing strong positive expression in epithelium (in brown) in IPF compared to NC, and similarly more positive expression in type 2 pneumocytes and alveolar macrophages in IPF than in NC.