Published ahead of print on August 1, 2003, doi:10.1165/rcmb.2003-0198OC
© 2004 American Thoracic Society DOI: 10.1165/rcmb.2003-0198OC Heterogeneity of Heparan Sulfates in Human LungDepartment of Biochemistry, University Medical Center Nijmegen, Nijmegen Center for Molecular Life Sciences, and Department of Pulmonary Diseases, University Medical Center Nijmegen, Nijmegen, The Netherlands Address correspondence to: Toin H. van Kuppevelt, Department of Biochemistry 194, Nijmegen Center for Molecular Life Sciences, University Medical Center Nijmegen, Nijmegen, P.O. Box 9101, 6500 HB Nijmegen, The Netherlands. E-mail: a.vankuppevelt{at}ncmls.kun.nl Heparan sulfates (HS), a class of glycosaminoglycans, are long linear complex polysaccharides covalently attached to a protein core. The HS molecules are made up of repeating disaccharides onto which modification patterns are superimposed. This results in a large structural heterogeneity and forms the basis of specific interactions of HS toward a vast array of proteins, including growth factors and proteases. To study HS heterogeneity in the lung, we used phage display technology to select seven antibodies against human lung HS. Antibodies reacted with HS/heparin, but not with other glycosaminoglycans or polyanions. Sulfate groups were essential for antibody binding. The amino acid sequence of the antibodies was established, the complementarity determining region 3 of the heavy chain containing basic amino acids. The antibodies defined HS epitopes with a characteristic tissue distribution. Antibody EV3A1 primarily stained macrophages. Other antibodies primarily stained basement membranes, but with different preference toward type of basement membrane. Antibody EV3C3 was the only antibody which clearly reacted with bronchiolar epithelial cells. In human lung parenchyma, basic fibroblast growth factor and vascular endothelial growth factor were largely bound by HS. Some antibodies blocked a basic fibroblast growth factorbinding site of HS, and one antibody blocked a vascular endothelial growth factorbinding site of heparin. Taken together, these data suggest a specific role for HS epitopes in human lung. The antibodies obtained may be valuable tools to study HS in pulmonary diseases.
Abbreviations: basic fibroblast growth factor, bFGF bovine serum albumin, BSA enzyme-linked immunosorbent assay, ELISA glycosaminoglycans, GAGs heparan sulfates, HS HS proteoglycans, HSPGs N-deacetylase/N-sulfotransferase-1, NDST-1 phosphate-buffered saline, PBS vascular endothelial growth factor, VEGF-1
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