CHEMICAL CHARACTERIZATION AND QUANTIFICATION OF PROTEOGLYCANS IN HUMAN POSTBURN HYPERTROPHIC AND MATURE SCARS

1. Samples of normal skin from four patients, postburn hypertrophic sc ar from five patients and postburn mature scar from six patients were analysed for hydroxyproline, water and uronic acid and extracted with guanidinium chloride to yield the proteoglycan pool, A large chondroit in sulphate proteoglycan and biglycan were purified from one hypertrop hic scar biopsy and decorin from a normal skin biopsy, by ion-exchange chromatography, gel-filtration and hydrophobic interaction chromatogr aphy. These purified proteoglycans were used in an inhibition ELISA as say to estimate the quantities of each in the tissue samples, 2. Sampl es of post-burn hypertrophic scar had on average 30% less hydroxyproli ne, 12% more water and 2.4 times as much uronic acid as normal skin, T hese differences were all statistically significant, whereas the small differences between mature scars and normal skin were not, The conten t of decorin in hypertrophic scars was only 25% of that in normal skin whereas the large chondroitin sulphate proteoglycan and biglycan were each about 6-fold higher, The mature scars had slightly elevated leve ls of large chondroitin sulphate proteoglycan and biglycan and a reduc ed content of decorin compared with normal skin but these differences were not statistically significant, 3. The results suggest that aberra nt proteoglycan metabolism is a significant factor contributing to the altered physical properties of hypertrophic scars and that maturation of post-burn scars is dependent on a return of the relative proportio ns and concentrations of proteoglycans to those characteristic of norm al dermis.