Increased gene expression of matrix metalloproteinase-3 (stromelysin) in skin fibroblasts from patients with severe recessive dystrophic epidermolysis bullosa

Gene expression of matrix metalloproteinase 3 (MMP-3=stromelysin) was examined in the skin fibroblasts obtained from patients with severe recessive dystrophic epidermolysis bullosa (RDEB). Steady-state mRNA level of MMP-3 was selectively increased in the unstimulated RDEB cells by a post-transcriptional mechanism. A parallel study on the susceptibility of type VII collagen to MMPs revealed that this type of collagen is degraded by MMP-3, but not by MMP-1(collagenase). These data suggest that MMP-3 may play an important role in the blister formation of the skin in RDEB patients by the degradation of anchoring fibrils consisting of type VII collagen.