Expression of a P-selectin ligand in zona pellucida of porcine oocytes and P-selectin on acrosomal membrane of porcine sperm cells. Potential implications for their involvement in sperm-egg interactions.
The selectin family of cell adhesion molecules mediates initial leukocyte adhesion to vascular endothelial cells at sites of inflammation. O-glycan structural similarities between oligosaccharides from human leukocyte P-selectin glycoprotein ligand-1 (PSGL-1) and from zona pellucida glycoproteins of porcine oocytes indicate the possible existence of a P-selectin ligand in the zona pellucida. Here, using biochemical as well as morphological approaches, we demonstrate that a P-selectin ligand is expressed in the porcine zona pellucida. In addition, a search for a specific receptor for this ligand leads to the identification of P-selectin on the acrosomal membrane of porcine sperm cells. In vitro binding of porcine acrosome-reacted sperm cells to oocytes was found to be Ca2+ dependent and inhibitable with either P-selectin, P-selectin receptor-globulin, or leukocyte adhesion blocking antibodies against P-selectin and PSGL-1. Moreover, porcine sperm cells were found to be capable of binding to human promyeloid cell line HL-60. Taken together, our findings implicate a potential role for the oocyte P-selectin ligand and the sperm P-selectin in porcine sperm-egg interactions.
Geng
J G
JG
Cell Biology and Inflammation Research, Pharmacia and Upjohn, Inc., Kalamazoo, Michigan 49001, USA. jian-guo.geng@am.pnu.com
Raub
T J
TJ
Baker
C A
CA
Sawada
G A
GA
Ma
L
L
Elhammer
A P
AP
D000177:Acrosome / Q000378:metabolism*; D000818:Animals; D002118:Calcium / Q000378:metabolism; D002462:Cell Membrane / Q000378:metabolism; D019040:E-Selectin / Q000378:metabolism; D005260:Female; D006801:Humans; D007124:Immunoenzyme Techniques; D008024:Ligands; D008297:Male; D008854:Microscopy, Electron; D009865:Oocytes / Q000378:metabolism*; D019007:P-Selectin / Q000502:physiology*; D011994:Recombinant Proteins; D013084:Sperm-Ovum Interactions; D013552:Swine; D015044:Zona Pellucida / Q000378:metabolism*
D019040:E-Selectin; D008024:Ligands; D019007:P-Selectin; D011994:Recombinant Proteins; D002118:Calcium