CD274 and idiopathic pulmonary fibrosis: The fibrotic effect of PDL1 in IPF arises from intricate cellular interactions and signaling pathways, with the following mechanisms assuming paramount significance(Figure 4): firstly, overexpression of PDL1 in lung fibroblasts exerts resistance to myoblast apoptosis and eludes macrophage phagocytosis via the inhibition of p53 pathway or activation of FAK pathway.