Immunohistochemical studies on proteoglycan expression in normal skin and chronic ulcers

Background Proteoglycans (PGs) represent a large family of complex molecule s. They are found either as integral membrane components or constituents of the extracellular matrix. Their protein backbones are linked to different glycosaminoglycans, such as dermatan-, chondroitin-, keratan- or heparan su lphate. The molecules have specific functions during developmental processe s as well as in diseases, such as cancer and inflammation. Objectives The expression patterns of various cell-associated heparan and c hondroitin/dermatan-sulphate PGs in human skin and chronic venous ulcers we re investigated, Methods Tissue sections from 11 patients with chronic venous ulcers were us ed in this study Monoclonal antibodies were used for detection of the prote oglycans syndecan-1, -2 and -4, glypican, CD44 and perlecan. Results The different PGs exhibited individual staining patterns. Syndecan- 1 and -4 and glypican expression in chronic ulcers differed from the staini ng in normal skin. Whereas the expression of syndecan-4 and glypican in int act skin was mostly in the pericellular regions of keratinocytes, the epide rmal cells from the wound edge contained mostly intracellular PGs. In the w ound edge, syndecan-4 was predominantly expressed by epidermal basal layer cells. Syndecan-1 was less expressed at the epidermal wound margins. PGs bi nd growth factors, regulate proteolytic activity and act as matrix receptor s. Conclusions The altered expression patterns of glypican and syndecan-1 and -4 in chronic ulcers reflect their possible roles during inflammation and c ell proliferation, Hence, analysis of PG expression should be of interest i n future studies on normal as well as defective wound healing.