While MMP12 functions in SSc-ILD have not been defined, MMP12 downregulated expression of collagenase MMP13 in a Schistosoma mansoni Th2-driven model of lung fibrosis (Madala et al., 2010), providing a crucial example of MMP-dependent regulation of other metalloproteinases. The gene discussed is MMP13; the disease is systemic sclerosis.