title: Modification at C6 of the terminal galactosyl residues of cobra venom factor abolishes anti-alpha-Gal antibody immunoreactivity without affecting functional activity.
abstract: The N-linked oligosaccharides of cobra venom factor (CVF) contain unique terminal alpha-galactosylated Lewis X structures. We have previously shown that CVF immobilized on nylon membranes binds naturally occurring human anti-alpha-Gal antibody. The present study shows that soluble CVF can effectively inhibit the binding of anti-alpha-Gal antibody to CVF-coated microtiter plates, indicating that the terminal alpha-galactosyl residues of the functionally active CVF are accessible to anti-alpha-Gal antibody binding. Modification of the terminal galactosyl residues of CVF by treatment with galactose oxidase and in situ derivatization of the generated aldehyde groups with hydrazides abolished the human anti-alpha-Gal antibody immunoreactivity without affecting the complement-activating activity.
authors.affiliation: Department of Biochemistry and Molecular Biology, Georgetown University Medical Center, Washington, DC, 20007, USA.
authors.forename: D C
authors.initials: DC
authors.lastname: Gowda
mesh_terms: D000818:Animals; D000906:Antibodies / Q000276:immunology / Q000378:metabolism; D004546:Elapid Venoms / Q000737:chemistry* / Q000276:immunology; D005690:Galactose / Q000276:immunology*; D005692:Galactose Oxidase / Q000378:metabolism; D006023:Glycoproteins / Q000737:chemistry / Q000276:immunology; D006168:Guinea Pigs; D006461:Hemolysis / Q000187:drug effects; D006801:Humans; D006834:Hydrazines / Q000378:metabolism; D016256:Lewis X Antigen / Q000276:immunology
chemical_list: D000906:Antibodies; D004546:Elapid Venoms; D006023:Glycoproteins; D006834:Hydrazines; D016256:Lewis X Antigen; C016310:cobra venom factor; D005692:Galactose Oxidase; D005690:Galactose