Immunization of female rabbits with heat‐solubilized bovine zonae: Production of anti‐zona antibody and inhibition of fertility

Abstract

Bovine zonae were solubilized by heating t o 80°C in buffered saline. On injection of female rabbits with this solution, zona-specific antisera were produced that could be assayed on bovine eggs in vitro by immunofluorescence, coating, and inhibition of sperm-binding. When the latter was complete, the rabbits were found to be infertile. Immunofluorescence assays showed that the rabbit anti-bovine zona serum reacted as strongly with rabbit and rhesus monkey zonae as with homologous zonae. Strong cross-reaction was also observed with marmoset and dog zonae, but with hamster zonae the reaction was relatively weak. Key words: zona pellucida, contraception I N TRODU CTI ONIn previous experiments we demonstrated that the sperm receptor in the zona pellucida of the hamster egg is inactivated by certain proteases, although it is resistant t o others, eg, collagenase [Gwatkin, 19781 . On heating t o 65°C the zonae dissolve and on cooling they remain in solution. The solutions retain receptor activity that can be assayed by the ability of the zona material t o bind t o capacitated hamster spermatozoa [Gwatkin, 19781 and to block the fertilization of hamster eggs in vitro [Gwatkin and Williams, 19771. When used as a vaccine t o immunize mice, hamster zona solutions elicit the production of anti-zona antibody and produce a complete block t o fertility [Gwatkin, Williams, and Carlo, 19771. In order to study further the nature of the mammalian sperm receptor and of the contraceptive antigen, we are isolating a number of zona components in relatively large quantities from calf ovaries (see Gwatkin et a1 [ 19781 ). As part of this program we have also physically isolated calf zonae from follicular eggs, determined their heat solubility,

Localization of the mRNA encoding the zona protein ZP3α in the porcine ovary, oocyte and embryo by non-radioactivein situ hybridization

“…After fertilization, the porcine zona pellucida remains intact up to day 7 post ovulationem, supporting the cell contact of the cleaving blastomeres and protecting the embryo during its transit to the uterus (Dunbar et al, 1989). Antibodies directed against zona pellucida components can prevent sperm binding to the zona resulting in temporary infertility (Gwatkin et al, 1977;Gwatkin & Williams, 1978;Sacco, 1979;Gwatkin et al, 1980;Aitken & Richardson, 1981a,b;Tsunoda et al, 1981, Wood et al, 1981. This effect is not species specific, since the zonae pellucidae of different species share common antigen determinants.…”

Immunoelectrophoretic analysis of the porcine zona pellucida

“…22 (Dunbar & Raynor, 1980) (Dunbar & Raynor, 1980). Consequently, antiserum produced against SIZP is zona specific (Gwatkin & Williams, 1978;Gwatkin, Anderson & Williams, 1980;Dunbar & Raynor, 1980). The zona specificity of the remaining two antisera used in this investigation, anti-IZP and anti-PPZA, has previously been demonstrated (Palm et al, 1979;Subramanian et al, 1981).…”

Characterization of equine zona pellucida glycoproteins by polyacrylamide gel electrophoresis and immunological techniques

“…It is well known that disturbing ZP function by active immunization with heterologous ZP antigens alters fertility in rabbits (Gwatkin & Williams, 1978;Gwatkin et ai, 1980;Wood et al, 1981), dogs (Mahi-Brown et ai, 1982), primates (Gulyas et ai, 1983;Sacco et ai, 1989), horses (Liu et al, 1989;Kirkpatrick et ai, 1990) and mice (Gwatkin et al, 1977). Clinical application of this knowledge to provide methods of immunocontraception for domestic and feral equine populations will ultimately rely upon recombinant techniques (Tyndale-Biscoe, 1991).…”