title: Monoclonal antibody c262 counteracts the stimulatory effect of progesterone on sperm-oocyte fusion.
abstract: Some evidence suggests that the non-genomic effects exerted by progesterone (P) on human spermatozoa are mediated by membrane receptor(s) displaying the C-terminal domain, but not the N-terminal domain of the genomic P receptor (PR). This study aimed at determining whether the monoclonal antibody (mAb) c-262, directed against the C-terminal domain of the genomic PR, counteracts the stimulatory effect of P on the human sperm ability to fuse with oocytes. Sperm/oocyte fusion was evaluated by means of the hamster egg penetration test. The brief exposure of capacitated spermatozoa to P produced a stimulatory effect on sperm/oocyte fusion. mAb c262 counteracted this stimulatory effect in a dose-dependent manner. No counteraction was observed when capacitated spermatozoa were pre-exposed to PGR-312, a mAb directed against the N-terminal domain of the genomic PR. These results reinforce the hypothesis that the non-genomic effects exerted by P on human spermatozoa are mediated by membrane receptor(s) displaying the C-terminal domain, but not the N-terminal domain of the genomic PR.
authors.affiliation: Andrologic Unit, Department of Internal Medicine, University of L'Aquila, 76100 L'Aquila, Italy.
authors.forename: C
authors.initials: C
authors.lastname: Pandolfi
authors.forename: B
authors.initials: B
authors.lastname: Macerola
authors.forename: A
authors.initials: A
authors.lastname: Zugaro
authors.forename: R
authors.initials: R
authors.lastname: Santucci
authors.forename: S
authors.initials: S
authors.lastname: Francavilla
authors.forename: F
authors.initials: F
authors.lastname: Francavilla
mesh_terms: D000911:Antibodies, Monoclonal / Q000276:immunology*; D006801:Humans; D008297:Male; D011374:Progesterone / Q000037:antagonists & inhibitors*; D013084:Sperm-Ovum Interactions / Q000187:drug effects / Q000276:immunology*
chemical_list: D000911:Antibodies, Monoclonal; D011374:Progesterone