PATTERNS OF MATRIX METALLOPROTEINASE AND TIMP-1 EXPRESSION IN CHRONICAND NORMALLY HEALING HUMAN CUTANEOUS WOUNDS

The present study was carried out to characterize the patterns of expr ession of matrix metalloproteinases or their tissue inhibitor (TIMP-1) in normally healing, acute vs, chronic, skin wounds. In situ hybridiz ation was performed to localize collagenase, stromelysin-l, stromelysi n-2, matrilysin, urokinase plasminogen activator (uPA) and TIMP-1 mRNA s in 14 chronic venous ulcers and 10 normally healing wounds, represen ting different time points after wounding. Surgical wounds, made in pi glets harvested at several time points, were studied as controls. Coll agenase, stromelysin-l and -2, as well as uPa, were expressed in kerat inocytes in both acute and chronic wounds, while epithelial TIMP-1 mRN A was not detected in any chronic wound biopsies studied. However, TIM P-1 was expressed at the epithelial edges of both acute human and pig wounds. Our results suggest that the balance between metalloenzymes an d their inhibitor TIMP-1, is disturbed, in poorly healing wounds.