A chondroitin/dermatan sulfate form of CD44 is a receptor for collagen XIV (undulin).
Collagen XIV, a fibril-associated collagen with interrupted triple helices, is expressed in differentiated soft connective tissues and in cartilage. However, a cellular receptor for this protein has not been identified. Here we show that human placental collagen XIV, isolated by a mild and simple two-step method, serves as adhesive protein for a variety of mesenchymal and some epithelial cells. Cell adhesion could be inhibited by preincubation of the collagen XIV substrate with heparin or with the chondroitin/dermatan sulfate proteoglycan decorin and by pretreatment of cells with chondroitinase ABC or heparinase III, suggesting a cell membrane proteoglycan as receptor. Affinity chromatography of 125I-labeled fibroblast cell surface proteins on collagen XIV-Sepharose yielded a chondroitin/dermatan sulfate proteoglycan with a molecular mass of 97-105 kDa after chondroitinase ABC digestion and of 60-70 kDa after further treatment with N-glycosidase F. The eluates contained also some high-molecular-weight material that was susceptible to digestion with heparinase but no detectable integrins. Immunoprecipitation with a specific monoclonal antibody identified the prominent chondroitin/dermatan sulfate proteoglycan as a member of the CD44 family. The interaction between collagen XIV and cells appears to be finely tuned, since matrix-associated glycosaminoglycans, and particularly proteoglycans like decorin, could compete with cells for the binding site(s) on collagen XIV under physiological conditions.
Ehnis
T
T
Klinikum Benjamin Franklin, Department of Gastroenterology, Free University of Berlin, Hindenburgdamm 30, Berlin, D-12200, Germany.
Dieterich
W
W
Bauer
M
M
Lampe
B
B
Schuppan
D
D
D002448:Cell Adhesion; D002460:Cell Line; D002808:Chondroitin Lyases; D002809:Chondroitin Sulfates / Q000302:isolation & purification / Q000378:metabolism*; D002846:Chromatography, Affinity; D003094:Collagen / Q000378:metabolism*; D003871:Dermatan Sulfate / Q000302:isolation & purification / Q000378:metabolism*; D005260:Female; D005347:Fibroblasts / Q000378:metabolism; D006023:Glycoproteins / Q000378:metabolism*; D006801:Humans; D018960:Hyaluronan Receptors / Q000737:chemistry* / Q000378:metabolism*; D066298:In Vitro Techniques; D016023:Integrins / Q000737:chemistry* / Q000378:metabolism*; D010920:Placenta / Q000378:metabolism; D011247:Pregnancy; D038981:Receptors, Collagen
C054447:COL14A1 protein, human; D006023:Glycoproteins; D018960:Hyaluronan Receptors; D016023:Integrins; D038981:Receptors, Collagen; D003871:Dermatan Sulfate; D002809:Chondroitin Sulfates; D003094:Collagen; D002808:Chondroitin Lyases