Proteoglycan synthesis in human skin and burn scar explant cultures

The synthesis of proteoglycans (PG) by normal human skin, and normal and hypertrophic scars were compared using tissue explants in culture. Newly synthesized PG were labelled with [35S]Na2SO4. Significant differences were found in the proportion of [35S]-radio-labelled incorporation of PG in the tissue and accumulation of [35S]PG in culture medium in the different tissues. The rate of PG biosynthesis in all three tissue types occurred in two phases. There was an initial phase of PG synthesis occurring at 0-3 h and a later phase that occurred at 3-18 h [35S]-labelled PG were isolated and characterized by Sepharose CL-6B chromatography and cellulose acetate electrophoresis. The results showed that the hypertrophic scar tissue and its culture medium contained higher proportions of dermatan sulphate (DS), chondroitin sulphate (CS) and DS' PG than the normal skin fractions. These results suggest that abnormal scarring is related to a change in the level of PG synthesis during the burn injury repair process.