Antibody recognition of epitopes on wild-type and mutant β-(1⃗4)-galactosyltransferase-1

• Published in: Carbohydrate research Vol. 313; no. 1; pp. 37 - 48
• Main Authors: Keusch, Jeremy, Panayotou, George, Malissard, Martine, Berger, Eric G., Appert, Hubert E., Lydyard, Peter M., Delves, Peter J.
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier Ltd 01.11.1998
• Subjects: Antibodies, Monoclonal; beta-N-Acetylglucosaminylglycopeptide beta-1,4-Galactosyltransferase - genetics; beta-N-Acetylglucosaminylglycopeptide beta-1,4-Galactosyltransferase - immunology; Catalysis; Epitope Mapping; Galactosyltransferase; Glycosyltransferase; Golgi; Humans; Monoclonal antibodies; Mutation; N-Acetyllactosamine Synthase - genetics; N-Acetyllactosamine Synthase - immunology; Surface plasmon resonance; Synergistic antibody binding; UDP-galactose: β- N-acetylglucosamine β-(1⃗4)-galactosyltransferase ( β4Gal-T, EC 2.4.1.38/90); rh β4Gal-T1, recombinant human β4Gal-T1; GlcNAc, N-acetylglucosamine; Glycosyltransferase; mAbs, monoclonal antibodies; Monoclonal antibodies; Galactosyltransferase; PNPP, p-nitrophenyl phosphate; Golgi; Surface plasmon resonance; SPR, surface plasmon resonance; Synergistic antibody binding; β4Gal-T
• ISSN: 0008-6215; 1873-426X
• DOI: 10.1016/S0008-6215(98)00247-X

The epitopes present on β-(1⃗4)-galactosyltransferase-1 ( β4Gal-T1) have been explored using a panel of monoclonal antibodies (mAbs) raised against the soluble form of the human enzyme. Reactivity of the antibodies with site-specific and truncated mutants of human β4Gal-T1 suggests the presence of a major immunogenic epitope cluster consisting of four epitopes within the stem region and mapping between amino acids 42 and 115. The catalytic activity of the enzyme is increased in the presence of stem region-specific antibody. Two of the epitopes were further localized to a region between amino acids 42 and 77, sequences which are not shared with the recently cloned β4Gal-T2 and β4Gal-T3 enzymes. An epitope located close to or within the catalytic domain is also identified, and the mAb to this region binds synergistically with antibodies to the stem region.