Characterization of a monoclonal antibody that recognizes an arabinosylated (1-->6)-beta-D-galactan epitope in plant complex carbohydrates

Carbohydr Res. 1995 Oct 2;275(2):295-307. doi: 10.1016/0008-6215(95)00174-r.

Abstract

Monoclonal antibody CCRC-M7 is representative of a group of antibodies with similar binding specificity that were generated using the plant cell-wall pectic polysaccharide, rhamnogalacturonan I, as immunogen. The epitope recognized by CCRC-M7 is present in several plant polysaccharides and membrane glycoproteins. Selective enzymatic or chemical removal of arabinosyl residues from rhamnogalacturonan I reduced, but did not abolish, the ability of CCRC-M7 to bind to the polysaccharide. In contrast, enzymatic removal of both arabinosyl and galactosyl residues from rhamnogalacturonan I completely abolished binding of CCRC-M7 to the resulting polysaccharide. Competitive ELISAs using chemically defined oligosaccharides to compete for the CCRC-M7 binding site showed that oligosaccharides containing (1-->6)-linked beta-D-galactosyl residues were the best competitors among those tested, with the tri-, penta-, and hexa-saccharides being equally effective. The combined results from indirect and competitive ELISAs suggest that the minimal epitope recognized by CCRC-M7 encompasses a (1-->6)-linked beta-galactan containing at least three galactosyl residues with at least one arabinosyl residue attached.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Antibodies, Monoclonal / immunology*
  • Binding Sites, Antibody
  • Binding, Competitive
  • Cell Wall / chemistry*
  • Cells, Cultured
  • Chromatography, High Pressure Liquid
  • Enzyme-Linked Immunosorbent Assay
  • Epitopes / chemistry
  • Epitopes / immunology*
  • Galactans / chemistry
  • Galactans / immunology*
  • Hydrolysis
  • Molecular Structure
  • Pectins / chemistry
  • Pectins / immunology*
  • Plants / chemistry*

Substances

  • Antibodies, Monoclonal
  • Epitopes
  • Galactans
  • rhamnogalacturonan I
  • Pectins
  • arabinogalactan