Activities of the matrix metalloproteinase stromelysin-2 (MMP-10) in matrix degradation and keratinocyte organization in wounded skin

• Published in: Molecular biology of the cell Vol. 15; no. 12; pp. 5242 - 5254
• Main Authors: Krampert, Monika, Bloch, Wilhelm, Sasaki, Takako, Bugnon, Philippe, Rülicke, Thomas, Wolf, Eckhard, Aumailley, Monique, Parks, William C, Werner, Sabine
• Format: Journal Article
• Language: English
• Published: United States The American Society for Cell Biology 01.12.2004
• Subjects: Animals; Apoptosis; Cell Adhesion Molecules - metabolism; Cell Movement; Cells, Cultured; Epithelium - pathology; Extracellular Matrix - enzymology; Extracellular Matrix - pathology; Female; Focal Adhesion Kinase 1; Focal Adhesion Protein-Tyrosine Kinases; Gene Expression; Humans; Integrin beta1 - metabolism; Kalinin; Keratinocytes - enzymology; Keratinocytes - pathology; Male; Matrix Metalloproteinase 10; Metalloendopeptidases - genetics; Metalloendopeptidases - metabolism; Mice; Mice, Transgenic; Mutation - genetics; Phosphorylation; Protein Serine-Threonine Kinases - metabolism; Protein-Tyrosine Kinases - metabolism; Proto-Oncogene Proteins - metabolism; Proto-Oncogene Proteins c-akt; Signal Transduction; Skin - cytology; Skin - enzymology; Skin - pathology; Skin Diseases - enzymology; Skin Diseases - genetics; Skin Diseases - pathology; Wound Healing; Wounds and Injuries - enzymology; Wounds and Injuries - genetics; Wounds and Injuries - pathology
• ISSN: 1059-1524; 1939-4586
• DOI: 10.1091/mbc.E04-02-0109

The matrix metalloproteinase stromelysin-2 is expressed in keratinocytes of the epithelial tongue of skin wounds, suggesting a role in keratinocyte migration. Here, we show that stromelysin-2 enhances migration of cultured keratinocytes. To gain insight into the in vivo activities of stromelysin-2 in epithelial repair, we generated transgenic mice expressing a constitutively active stromelysin-2 mutant in keratinocytes. These animals had no alterations in skin architecture, and the healing rate of skin wounds was normal. Histologically, however, we found abnormalities in the organization of the wound epithelium. Keratinocytes at the migrating epidermal tip were scattered in most sections of mice with high expression level, and there was a reduced deposition of new matrix. In particular, the staining pattern of laminin-5 at the wound site was altered. This may be due to proteolytic processing of laminin-5 by stromelysin-2, because degradation of laminin-5 by this enzyme was observed in vitro. The inappropriate matrix contact of keratinocytes was accompanied by aberrant localization of beta1-integrins and phosphorylated focal adhesion kinase, as well as by increased apoptosis of wound keratinocytes. These results suggest that a tightly regulated expression level of stromelysin-2 is required for limited matrix degradation at the wound site, thereby controlling keratinocyte migration.