title: Specificity of serum anti-A(di) IgG antibodies from patients with gastrointestinal cancer.
abstract: Changes in the glycosylation in cancer may lead to an aberrant expression of A, B incompatible or xenogeneic blood group related antigens. To characterize the specificity of IgG antibodies to A, B, and related glycans in sera of gastrointestinal cancer patients, serum probes and affinity-isolated antibodies were analyzed in the indirect and competitive ELISA using a set of homogenous polyacrylamide (PAA) glycoconjugates. Monoreactive antibodies recognizing A(di) (I) and cross-reactive antibodies to A(di)/B(di)/B(tri) (II) or A(di)/A(tri)/Fs(di)/Core5 (III) were affinity-isolated on A(di)-PAA-Sepharose. The population I showed a higher affinity to A(di)-PAA than cross-reactive antibodies. The antibodies II were more specific to B(di) and may belong to the core alpha-Gal reactive antibodies but are also capable of recognizing A(di). The antibodies III were more specific to A(tri); they agglutinated A-erythrocytes and belong to anti-A isoantibodies reactive to xenogeneic oligosaccharides. The purified antibody samples were non- or faintly reactive to Tn. The IC(50) values of PAA glycoconjugates ranged from 6 × 10(-8) to 7 × 10(-6) M. No or weak binding of antibodies to the unrelated antigens used in the detection of polyreactivity (ferritin, casein, and DNA) was observed.
authors.affiliation: Department of Oncology and Immunology, National Institute for Health Development, Tallinn, Estonia. jevgeni.smorodin@tai.ee
authors.forename: Eugeniy P
authors.initials: EP
authors.lastname: Smorodin
authors.forename: Oleg A
authors.initials: OA
authors.lastname: Kurtenkov
authors.forename: Boris L
authors.initials: BL
authors.lastname: Sergeyev
authors.forename: Jelena S
authors.initials: JS
authors.lastname: Branovets
authors.forename: Jelena G
authors.initials: JG
authors.lastname: Izotova
authors.forename: Andrey A
authors.initials: AA
authors.lastname: Formanovsky
mesh_terms: D000328:Adult; D000368:Aged; D000918:Antibody Specificity / Q000276:immunology*; D002851:Chromatography, High Pressure Liquid; D004797:Enzyme-Linked Immunosorbent Assay; D005500:Follow-Up Studies; D005770:Gastrointestinal Neoplasms / Q000097:blood / Q000276:immunology*; D006801:Humans; D007074:Immunoglobulin G / Q000097:blood / Q000276:immunology* / Q000302:isolation & purification; D008875:Middle Aged
chemical_list: D007074:Immunoglobulin G