MMP9 and systemic sclerosis: Although fewer studies have been conducted on other MMPs, some reports also reached the same results as ours showing elevated levels of MMP-9 (Guiot et al. 2020; Kim et al. 2005) and MMP-12 (Bonhomme et al. 2019; Manetti et al. 2012) in patients with SSc-ILD+.