CA-125 of fetal origin can act as a ligand for dendritic cell-specific ICAM-3-grabbing non-integrin

Cell Mol Biol Lett. 2014 Jun;19(2):249-61. doi: 10.2478/s11658-014-0194-4. Epub 2014 Apr 24.

Abstract

CA-125 (coelomic epithelium-related antigen) forms the extracellular portion of transmembrane mucin 16 (MUC16). It is shed after proteolytic degradation. Due to structural heterogeneity, CA-125 ligand capacity and biological roles are not yet understood. In this study, we assessed CA-125 as a ligand for dendritic cell-specific ICAM-3-grabbing non-integrin (DC-SIGN), which is a C-type lectin showing specificity for mannosylated and fucosylated structures. It plays a role as a pattern recognition molecule for viral and bacterial glycans or as an adhesion receptor. We probed a human DC-SIGN-Fc chimera with CA-125 of fetal or cancer origin using solid- or fluid-phase binding and inhibition assays. The results showed that DC-SIGN binds to CA-125 of fetal origin and that this interaction is carbohydrate-dependent. By contrast, cancer-derived CA-125 displayed negligible binding. Inhibition assays indicated differences in the potency of CA-125 to interfere with DC-SIGN binding to pathogen-related glycoconjugates, such as mannan and Helicobacter pylori antigens. The differences in ligand properties between CA-125 of fetal and cancer origin may be due to specificities of glycosylation. This might influence various functions of dendritic cells based on their subset diversity and maturation-related functional capacity.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • CA-125 Antigen / chemistry
  • CA-125 Antigen / isolation & purification
  • CA-125 Antigen / metabolism*
  • Cell Adhesion Molecules / chemistry
  • Cell Adhesion Molecules / genetics
  • Cell Adhesion Molecules / metabolism*
  • Cell Line, Tumor
  • Fetus / metabolism*
  • Glycoconjugates / chemistry
  • Glycoconjugates / metabolism
  • Humans
  • Immobilized Proteins / chemistry
  • Immobilized Proteins / metabolism
  • Lectins, C-Type / chemistry
  • Lectins, C-Type / genetics
  • Lectins, C-Type / metabolism*
  • Ligands
  • Protein Binding
  • Protein Structure, Tertiary
  • Receptors, Cell Surface / chemistry
  • Receptors, Cell Surface / genetics
  • Receptors, Cell Surface / metabolism*
  • Recombinant Fusion Proteins / biosynthesis
  • Recombinant Fusion Proteins / chemistry
  • Recombinant Fusion Proteins / genetics

Substances

  • CA-125 Antigen
  • Cell Adhesion Molecules
  • DC-specific ICAM-3 grabbing nonintegrin
  • Glycoconjugates
  • Immobilized Proteins
  • Lectins, C-Type
  • Ligands
  • Receptors, Cell Surface
  • Recombinant Fusion Proteins