The top upregulated DE genes in IPF macrophage (Fig. 4b), such as FN1, CCL18 and SPP1, were previously reported to be upregulated in IPF and related to IPF pathogenesis in macrophages [17, 18, 44, 45, 47, 48, 51]. This evidence concerns the gene SPP1 and idiopathic pulmonary fibrosis.