title: Mapping of epitopes relevant for induction of acrosome reaction on human zona pellucida glycoprotein-4 using monoclonal antibodies.
abstract: OBJECTIVE
  To decipher structural and functional aspects of human zona pellucida glycoprotein-4 (ZP4), the epitopes recognized by monoclonal antibodies (MAbs) have been mapped.
  
  
  METHODS
  Recombinant human ZP4-mediated induction of acrosome reaction in human sperm was studied in the absence and presence of ZP4-specific MAbs. The epitopes of MAbs were mapped using recombinant peptides expressed in Escherichia coli.
  
  
  RESULTS
  Monoclonal antibodies (MA-1662, MA-1671) against human ZP4 showed specific binding to ZP matrix of human eggs in an indirect immunofluorescence assay. Both the antibodies showed significant (P < 0.05) inhibition in the baculovirus-expressed recombinant ZP4-mediated acrosome reaction. MA-1671 recognized N-terminal fragment of ZP4 and minimal epitope mapped to amino acid residues 126-130 (PARDR), whereas MA-1662 reacted to C-terminal fragment and minimal epitope mapped to amino acid residues 256-260 (ENELV).
  
  
  CONCLUSIONS
  The epitopes corresponding to both N- and C-terminal parts of human ZP4 may be relevant for its biological activity.
authors.affiliation: Department of Reproductive Biology, Shanghai Institute of Planned Parenthood Research, Shanghai 200032, China.
authors.forename: Wan-Xiang
authors.initials: WX
authors.lastname: Xu
authors.forename: Beena
authors.initials: B
authors.lastname: Bhandari
authors.forename: Ya-Ping
authors.initials: YP
authors.lastname: He
authors.forename: Hai-Ping
authors.initials: HP
authors.lastname: Tang
authors.forename: Sanchita
authors.initials: S
authors.lastname: Chaudhary
authors.forename: Pankaj
authors.initials: P
authors.lastname: Talwar
authors.forename: Satish K
authors.initials: SK
authors.lastname: Gupta
authors.forename: Jian
authors.initials: J
authors.lastname: Wang
mesh_terms: D020101:Acrosome Reaction; D000595:Amino Acid Sequence; D000911:Antibodies, Monoclonal / Q000276:immunology; D004527:Egg Proteins / Q000737:chemistry / Q000276:immunology* / Q000502:physiology*; D018604:Epitope Mapping; D000939:Epitopes / Q000276:immunology*; D006801:Humans; D008297:Male; D008562:Membrane Glycoproteins / Q000737:chemistry / Q000276:immunology* / Q000502:physiology*; D008969:Molecular Sequence Data; D011994:Recombinant Proteins; D016415:Sequence Alignment; D013094:Spermatozoa / Q000276:immunology; D015044:Zona Pellucida / Q000276:immunology*; D000072216:Zona Pellucida Glycoproteins
chemical_list: D000911:Antibodies, Monoclonal; D004527:Egg Proteins; D000939:Epitopes; D008562:Membrane Glycoproteins; D011994:Recombinant Proteins; C082833:ZP4 protein, human; D000072216:Zona Pellucida Glycoproteins