CD163 and fibrosis: Importantly, CD163-expressing monocyte-derived macrophages may associate with fibroblasts in the lungs of patients with COVID-19-related ARDS [166] and are implicated in fibrosis progression in idiopathic pulmonary fibrosis (IPF) [167], suggesting CD163-expressing monocyte-derived macrophages may represent a link between ARDS and fibrotic lung disease.