MMP1 and COVID-19: In a follow-up study of hospitalized patients with moderate and severe COVID-19, Safont and others (2022) reported that half of them exhibited impaired pulmonary diffusion, and the computed tomography (CT) scan from severe patients displayed fibrotic lesions and elevated serum PF biomarkers such as MMP1 and MMP7, both previously described as blood biomarkers in idiopathic PF (IPF) (Rosas and others 2008).