title: Altered keratan sulfate epitopes in keratoconus.
abstract: Extracts of normal and keratoconus human corneas were assayed for keratan sulfate (KS) and for the protein core of corneal keratan sulfate proteoglycan (KSPG), using a solid-phase immunoassay. Aliquots from guanidine-HCl extracts of four to six pooled corneas were adsorbed to nitrocellulose membrane and assayed for binding of a monoclonal antibody against KS or of an affinity-purified rabbit polyclonal antibody against the KSPG protein core using 125I-labeled secondary antibodies. The amount of antigen in the extracts was estimated from standard curves with purified bovine KSPG. Extracts from keratoconus corneas contained only an average of 48% as much (P less than 0.001) KS-antigen as normal corneal extracts when assayed with anti-KS monoclonal antibody. There was no significant difference in the amount of KSPG core protein antigens in keratoconus and normal corneal extracts. These results suggest that corneas with keratoconus contain a form of KSPG that contains fewer keratan sulfate chains or in which the keratan sulfate has a modified structure.
authors: Division of Biology, Kansas State University, Manhattan.
authors: J L
authors: JL
authors: Funderburgh
authors: N
authors: N
authors: Panjwani
authors: G W
authors: GW
authors: Conrad
authors: J
authors: J
authors: Baum
mesh_terms: D000911:Antibodies, Monoclonal / Q000276:immunology; D011508:Chondroitin Sulfate Proteoglycans / Q000276:immunology; D003315:Cornea / Q000276:immunology; D000939:Epitopes; D006025:Glycosaminoglycans / Q000276:immunology*; D006801:Humans; D007118:Immunoassay; D007632:Keratan Sulfate / Q000276:immunology*; D007640:Keratoconus / Q000276:immunology*; D000071234:Lumican
chemical_list: D000911:Antibodies, Monoclonal; D011508:Chondroitin Sulfate Proteoglycans; D000939:Epitopes; D006025:Glycosaminoglycans; C000604306:LUM protein, human; D000071234:Lumican; D007632:Keratan Sulfate