Patients with RA-ILD+ and SSc-ILD+ showed lower serum levels of MMP-7 and MMP-10 than those with IPF (RA: p < 0.0001, p = 0.0113, Fig. 2A; and SSc: p = 0.0126, p = 0.0057, Fig. 2B; respectively). Here, MMP7 is linked to idiopathic pulmonary fibrosis.