Contraceptive Vaccines Based on the Zona Pellucida Glycoproteins for Dogs and Other Wildlife Population Management

Abstract

Citation Gupta SK, Srinivasan VA, Suman P, Rajan S, Nagendrakumar SB, Gupta N, Shrestha A, Joshi P, Panda AK. Contraceptive vaccines based on the zona pellucida glycoproteins for dogs and other wildlife population management. Am J Reprod Immunol 2011; 66: 51–62 Zona pellucida (ZP) glycoproteins, by virtue of their critical role in fertilization, have been proposed as candidate antigens for the development of contraceptive vaccines. In this review, the potential of a ZP‐based contraceptive vaccine for the management of wildlife population, with special reference to street dogs, is discussed. Immunization of various animal species, including female dogs, with native porcine ZP led to inhibition of fertility, which was associated with the ovarian dysfunction. Immunization of female dogs with Escherichia coli‐expressed recombinant dog ZP glycoprotein‐3 (ZP3) either coupled to diphtheria toxoid or expressed as fusion protein with ‘promiscuous’ T non‐B‐cell epitope of tetanus toxoid also led to inhibition of fertility. To improve the contraceptive efficacy of ZP‐based contraceptive vaccine, various groups are working on improving the immunogen, use of DNA vaccine as prime‐boost strategy, and delivering the zona proteins/peptides presented on either virus‐like particles or entrapped in microsphere. Host‐specific live vectors such as ectromelia virus and cytomegalovirus have also been used to deliver mouse ZP3 in mice. Various studies show the enormous potential of the ZP‐based vaccine for the management of wildlife population, where permanent sterilization may be desirable.

Suppression of Fertility in Adult Dogs

“…The principle of ZP vaccine is that antibodies against ZP proteins would block the binding of the sperm preventing all the foresee events and maybe it will also affect folliculogenesis (Gupta et al. ).…”

“…Even though ZP3 vaccination had good results, the most appropriate method of vaccine delivery to target dog population remains to be addressed (Gupta et al. ).…”

“…All of these glycoproteins were able to induce immune responses; however, the self-immunization with canine ZP proteins produces a weak response. The principle of ZP vaccine is that antibodies against ZP proteins would block the binding of the sperm preventing all the foresee events and maybe it will also affect folliculogenesis (Gupta et al 2011).…”

“…The negative impact on reproduction of using selfimmunization ZP vaccines seems to depend on the glycoprotein used. Immunization against ZP2 failed to prevent pregnancy in mated bitches; therefore, canine ZP2 is not a good candidate for developing contraceptive vaccine (Gupta et al 2011). The same research group had a 75% success rate, three of four female dogs immunized with the recombinant dog ZP3-DT (diphtheria toxoid) failed to conceive suggesting that the dog ZP3 can be a potential candidate for the development of the contraceptive vaccine for controlling dog population.…”

“…The same research group had a 75% success rate, three of four female dogs immunized with the recombinant dog ZP3-DT (diphtheria toxoid) failed to conceive suggesting that the dog ZP3 can be a potential candidate for the development of the contraceptive vaccine for controlling dog population. Even though ZP3 vaccination had good results, the most appropriate method of vaccine delivery to target dog population remains to be addressed (Gupta et al 2011).…”