Antibodies against zona pellucida glycoproteins inhibit sperm-egg binding.

2003 AUG 6 - (NewsRx.com & NewsRx.net) -- Antibodies against Escherichia coli-expressed epitopes of zona pellucida glycoproteins inhibit in vitro human sperm-egg binding.

"To minimize ovarian dysfunction subsequent to immunization with zona pellucida (ZP) glycoproteins, synthetic peptides encompassing the antigenic B cell epitopes as immunogens have been proposed.

"In this study, attempts have been made to clone and express a recombinant chimeric protein encompassing the epitopes corresponding to bonnet monkey (Macaca radiata) ZP glycoprotein-1 (bmZP1, amino acid residues 132-147), ZP glycoprotein-2 (bmZP2, amino acid residues 86-113), and ZP glycoprotein-3 (bmZP3, amino acid residues 324-347). The above chimeric recombinant protein (r-bmZP123) was expressed as a polyhistidine fusion protein in Escherichia coli," researchers in India and Japan report.

"Immunoblot with murine monoclonal antibody, MA-813, generated against recombinant bmZP1 revealed a major band of approximately 10 kDa," said Neela Sivapurapu and collaborators at the National Institute of Immunology in New Delhi, India, and the Hyogo College of Medicine in Japan.

The authors continued, "The r-bmZP123 was purified on nickel-nitrilotriacetic acid resin under denaturing conditions. The female rabbits immunized with purified r-bmZP123 conjugated to diphtheria toxoid (DT) generated antibodies that reacted with r-bmZP123 and DT in an ELISA. In addition, the immune sera also reacted with E. coli expressed recombinant bmZP1, bmZP2, and bmZP3."