Matrix metalloproteinase activity correlates with blastema formation in the regenerating MRL mouse ear hole model
Article first published online: 14 JAN 2003
Copyright © 2003 Wiley-Liss, Inc.
Special Issue: Regeneration Special Issue
Volume 226, Issue 2, pages 377–387, February 2003
How to Cite
Gourevitch, D., Clark, L., Chen, P., Seitz, A., Samulewicz, S. J. and Heber-Katz, E. (2003), Matrix metalloproteinase activity correlates with blastema formation in the regenerating MRL mouse ear hole model. Dev. Dyn., 226: 377–387. doi: 10.1002/dvdy.10243
- Issue published online: 28 JAN 2003
- Article first published online: 14 JAN 2003
- Manuscript Accepted: 7 NOV 2002
- Manuscript Received: 15 AUG 2002
- NIH. Grant Numbers: AI42395, AI07518, DE13359
- NIH training grant
- collagen type I and IV;
- MRL mice;
The MRL mouse was proposed as a model of mammalian regeneration because it can close ear holes completely with the restoration of normal tissue. This regeneration process involves the formation of a blastema during healing, the re-appearance of cartilage and hair follicles, and healing without scarring. Such a process requires extensive tissue remodeling. To characterize differences in ear wounding responses between regenerating and nonregenerating mice, we examined and compared the extracellular matrix remodeling and the matrix metalloproteinase (MMP) and tissue inhibitor of metalloproteinase (TIMP) response in the MRL and C57BL/6 mouse strains after injury. We found a correlation between the MRL's ability to break down the basement membrane, form a blastema, and close ear hole wounds and an inflammatory response with neutrophils and macrophages seen in the ear after injury. These cells were positive for MMP-2 and MMP-9 as well as TIMP-2 and TIMP-3. Clear differences between the MRL and B6 response to injury were seen that could explain the differences in healing and blastema formation in the MRL and lack of it in the B6 mice. This finding was further supported by enzyme activity as determined by gelatin zymography. Developmental Dynamics 226:377–387, 2003. © 2003 Wiley-Liss, Inc.