While secreted osteopontin (OPN) levels were lower in cultures of IPF and PASC-F myeloid cells (Figure 3D), the levels of this cytokine were positively correlated with the phagocytic activity of myeloid cells from healthy donor and fibrotic lung samples (Figure 3E; p = 0.046). Here, SPP1 is linked to idiopathic pulmonary fibrosis.