GROWTH-INHIBITION OF CULTURED FIBROBLASTS BY EXTRACTS FROM HUMAN DERMIS

In incised wounds and deep partial thickness burns the resident fibrob lasts in the dermis remain inactive. The fibroblasts responsible for r epair at the dermal level come from the subdermal layer. The hypothesi s is that the inactivity of the dermal fibroblasts is due to an inhibi tory substance in the dermis. To test this hypothesis extracts were ma de of normal dermis and of mature scar tissue and these extracts were applied to fibroblasts growing in monolayer culture. Both extracts and cells were obtained from human tissue. It was shown that extracts, pa rticularly the extract made with citric acid/citrate buffer, pH 3.5, c aused inhibition of fibroblast growth. Present evidence suggests that the active principle may be a proteoglycan.