Differences in glycosylation and sperm-egg binding inhibition of pregnancy-related glycodelin

Biol Reprod. 2003 Nov;69(5):1545-51. doi: 10.1095/biolreprod.103.017830. Epub 2003 Jun 25.

Abstract

Glycodelin is a glycoprotein produced in many glands, particularly those of reproductive tissues. It appears as different glycoforms in amniotic fluid (glycodelin-A) and seminal plasma (glycodelin-S), but only glycodelin-A inhibits gamete adhesion. In the present study, glycodelin from secretory-phase endometrium, first-trimester pregnancy decidua, and midtrimester amniotic fluid was studied with respect to physicochemical properties, including glycosylation patterns and inhibitory activity of sperm-egg binding. Purified glycodelins from all these sources were similar in isoelectric focusing and in lectin immunoassays using lectins from Wisteria floribunda and Sambucus nigra. Likewise, the glycodelins inhibited sperm-egg binding in a dose-dependent manner, as measured by hemizona-binding assay. However, subtle quantitative physicochemical and biological differences were found between glycodelins from different sources as well as within the same tissue/fluid between different individuals. Differences were most pronounced between endometrial glycodelins from nonpregnancy and first-trimester pregnancy. The glycan structures studied by fast-atom bombardment mass spectrometry of individual amniotic fluid glycodelin-A samples also showed interindividual quantitative differences. In conclusion, glycodelins from different female reproductive tract tissues and amniotic fluid share substantial similarity, allowing all of them to be called glycodelin-A. However, these glycodelins exhibit quantitative physicochemical and functional differences between different sources and individuals.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Blotting, Western
  • Electrophoresis, Polyacrylamide Gel
  • Female
  • Glycodelin
  • Glycoproteins / chemistry
  • Glycoproteins / metabolism
  • Glycoproteins / physiology*
  • Glycosylation
  • Humans
  • Immunoassay
  • Isoelectric Focusing
  • Lectins
  • Polysaccharides / metabolism
  • Pregnancy / physiology*
  • Pregnancy Proteins / chemistry
  • Pregnancy Proteins / metabolism
  • Pregnancy Proteins / physiology*
  • Silver Staining
  • Spectrometry, Mass, Fast Atom Bombardment
  • Sperm-Ovum Interactions / physiology*

Substances

  • Glycodelin
  • Glycoproteins
  • Lectins
  • PAEP protein, human
  • Polysaccharides
  • Pregnancy Proteins