PMID: 7592613

 

    Legend: Sugar

Title : Structural analysis of the oligosaccharides derived from glycodelin , a human glycoprotein with potent immunosuppressive and contraceptive activities

Abstract :
  1. Glycodelin , also known as placental protein 14 ( PP14 ) or progesterone-associated endometrial protein ( PAEP ), is a human glycoprotein with potent immunosuppressive and contraceptive activities
  2. In this paper we report the first characterization of glycodelin-derived oligosaccharides
  3. Using strategies based upon fast atom bombardment and electrospray mass spectrometry we have established that glycodelin is glycosylated at Asn-28 and Asn-63
  4. The Asn-28 site carries high mannose, hybrid and complex-type structures , whereas the second site is exclusively occupied by complex-type glycans
  5. The major non-reducing epitopes in the complex-type glycans are: Gal beta 1-4GlcNAc (lacNAc), GalNAc beta 1-4GlcNAc (lacdiNAc), NeuAc alpha 2-6Gal beta 1-4GlcNAc (sialylated lacNAc), NeuAc alpha 2-6Gal beta 1-4GlcNAc (sialylated lacdiNAc), Gal beta 1-4(Fuc alpha 1-3)GlcNAc (Lewisx), and GalNAc beta 1-4(Fuc alpha 1-3)GlcNAc (lacdiNAc analogue of Lewisx).
  6. It is possible that the oligosaccharides the oligosaccharides bearing sialylated lacNAc sialylated lacNAc or lacdiNAc antennae may manifest immunosuppressive effects by specifically blocking adhesive and activation-related events mediated by CD22 , the human B cell associated receptor
  7. Oligosaccharides with fucosylated lacdiNAc antennae have previously been shown to potently block selectin-mediated adhesions and may perform the same function in glycodelin
  8. The potent inhibitory effect of glycodelin on initial human sperm-zona pellucida binding is consistent with our previous suggestion that this cell adhesion event requires a selectin-like adhesion process
  9. This result also raises the possibility that a convergence between immune and gamete recognition processes may have occurred in the types of carbohydrate ligands recognized in the human