Wound fluids and the pathogenesis of chronic wounds

To describe two areas of ongoing investigation into analysis of wound fluids that may eventually lead to better understanding of pathophysiology of chronic wounds and to improved care and treatment.

Studies used Lowry protein assay, sodium dodecyl sulfate-polyacrylamide gel electrophoresis, Western blotting, and zymography to analyze fluids from acute and chronic wounds and serum samples collected from healthy and affected volunteers.

Thirty-one subjects with ages ranging from 32 to 79 years participated in the research; fluid was collected from chronic wounds in 10 patients (two female, four male, and four unrecorded), fluid was collected from acute mastectomy wounds in 15 patients (all female); blister fluid and blood were collected from two volunteers (one male, one female); and blood for serum preparation was collected from four volunteers (two female, two male).

(1) Fibronectin degradation and (2) expression of matrix metalloproteinases.

Fibronectin can be degraded in fluid from chronic wounds but remains intact in blood-derived serum, plasma-derived serum, blister fluid, and mastectomy wound fluid. Matrix metalloproteinases are overexpressed in fluid from chronic wounds compared with mastectomy wound fluid, blood-derived serum, and plasma-derived serum. Matrix metalloproteinases are also expressed of somewhat higher levels in mastectomy fluid than in blood-derived and plasma-derived serum.

These studies identified two factors that may contribute to delayed healing of chronic wound: fibronectin degradation and overexpression of matrix metalioproteinases.