title: Influence of arginine-glycine-aspartic acid (RGD), integrins (alphaV and alpha5) and osteopontin on bovine sperm-egg binding, and fertilization in vitro.
abstract: Osteopontin (OPN), a phosphoprotein containing an arginine-glycine-aspartic acid (RGD) sequence, has been identified in cow oviduct epithelium and fluid. To investigate the potential role OPN in fertilization, we evaluated the ability of RGD peptide (arginine-glycine-aspartic), RGE peptide (arginine-glycine-glutamic acid), integrins alphaV and alpha5 antibodies and OPN antibody to influence bovine in vitro sperm-egg binding and fertilization. Treatment of sperm or oocytes with the RGD peptide prior fertilization significantly decreased in vitro sperm-egg binding and fertilization compared to the non-treated controls or those treated with RGE peptide. Binding and fertilization were also significantly decreased when in vitro matured bovine oocytes or sperm were pre-incubated with integrins alphaV and alpha5 antibodies at concentration ranging from 5 to 20 microg/mL. Addition of a rabbit polyclonal IgG antibody against purified bovine milk OPN with sperm or/and oocytes decreased (P<0.05) fertilization compared to the in vitro-fertilized control. These data provided evidence that integrin ligands existed on bovine oocytes and spermatozoa that contained RGD recognition sequences, and that antibody to OPN, a protein that contains that RGD sequence, was capable of reducing sperm-egg binding and fertilization in vitro.
authors.affiliation: The John O. Almquist Research Center, Department of Dairy and Animal Science, The Pennsylvania State University, University Park, PA, USA.
authors.forename: R F
authors.initials: RF
authors.lastname: Gonçalves
authors.forename: C D
authors.initials: CD
authors.lastname: Wolinetz
authors.forename: G J
authors.initials: GJ
authors.lastname: Killian
mesh_terms: D000818:Animals; D000906:Antibodies / Q000378:metabolism / Q000494:pharmacology; D002417:Cattle / Q000502:physiology*; D005260:Female; D005307:Fertilization in Vitro / Q000662:veterinary; D039482:Integrin alpha5 / Q000276:immunology / Q000378:metabolism; D039564:Integrin alphaV / Q000276:immunology / Q000378:metabolism; D008297:Male; D009842:Oligopeptides / Q000494:pharmacology*; D053495:Osteopontin / Q000276:immunology / Q000378:metabolism; D011506:Proteins / Q000276:immunology / Q000378:metabolism*; D013084:Sperm-Ovum Interactions / Q000187:drug effects* / Q000502:physiology*
chemical_list: D000906:Antibodies; D039482:Integrin alpha5; D039564:Integrin alphaV; D009842:Oligopeptides; D011506:Proteins; C112658:arginyl-glycyl-glutamic acid; D053495:Osteopontin; C047981:arginyl-glycyl-aspartic acid