development of a next generation pzp vaccine · 2018-05-10 · development of a next generation pzp...
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Development of a next generation PZP vaccine
Harm HogenEsch, DVM, PhD
Ideal fertility control strategy(John W. Turner, Jr.)
• Highly effective• Multi-year duration• Reversible• No loss of basic social structure or sexual
behavior• No effect on existing pregnancy• No toxicity to recipient or applicator• Cannot pass through food chain• Can be delivered remotely• Cost effective
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Immunocontraception
• Induction of an immune response that inhibits fertility
• Potential targets:
– Hormones
• Gonadotropin releasing hormone (GnRH)
– Oocyte
• Zona pellucida proteins
– Sperm
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Porcine Zona Pellucida (PZP) vaccine
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Antibodies against ZP prevent binding of sperm and fertilization
Gupta et al., J Reprod Immunol 2009
PZP vaccine
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Oocyte
ZP2
ZP3
ZP4
ona pellucida
The immune responseto vaccines
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CD4+
B
lymph
dendritic cells
plasma cells
Types of vaccines
• Modified live vaccines - MMR
• Inactivated vaccines - polio
• Subunit vaccines:
– Viral proteins - hepatitis B
– Bacterial proteins - DTP
– Bacterial polysaccharides - Pneumococcus
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Subunit vaccines have two essential components
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Antigen*
Adjuvant
immuneresponse
protection
vaccine
Gaston Ramon
• 1886 – 1963
• 1906-1910 – l'Ecole NationaleVétérinaire d'Alfort
• Institut Pasteur – serum production in horses against diphtheria and tetanus
• Developed method to enhance antibody production.
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Adjuvants
Adjuvants
• Increase the magnitude of the immune response;
• Induce a specific type of immune response;
• Decrease the antigen dose and number of injections;
• Increase duration of immunity.
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PZP vaccines• Zonastat-H and Zonastat-D
– Protein extract from swine ovaries– 1st dose – modified complete Freund’s adjuvant
2nd dose – incomplete Freund’s adjuvant– Approved by the EPA for use in wildlife – Induces about 1 year of infertility
• PZP-22– Protein extract from swine ovaries– Slow release pellet (poly(lactide co-glycolide), PLGA)– QS-21 adjuvant– 2 years of infertility when combined with primer
• Spayvac®– Protein extract from swine ovaries– Liposome formulation
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Zonastat and PZP-22
• Porcine ovary proteins– poorly defined– immune response damages ovaries
• Adjuvants:– Freund’s adjuvant:
• Difficult to mix• Painful• Can cause abscesses• Not compatible with controlled release formulations
– QS-21• Unstable• Release profile from pellets is unknown
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Next generation PZP vaccine
• Effective long-lasting immune response after single injection;
• Easy to administer;
• Safe for the animals and environment;
• Well characterized and consistent among batches.
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Experimental approach
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Improved adjuvant• Potent• Safe• Compatible with
controlled release formulation
Recombinant PZP• Well characterized• Consistent
Controlled release
• Reproducible • Administered
in darts
Next generation PZP vaccine
Nano-11
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sweet corn variant – sugary-1
phytoglycogen
Nano-11
+ OSA and CHPTAC
Nano-11 enhances the antibody response
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Combination adjuvant
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Testing combination adjuvants in vitro
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PBMC + 5% serum
24 h
ELISA for IL-1β, TNF, CXCL10
Effect of combination adjuvants on cytokines production by equine PBMCs
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Recombinant PZP proteins
20http://www.amsbio.com/bacterial-protein-expression-services.aspx
Zona pellucida proteins
ZP1 ZP2 ZP3 ZP4
Human + + + +
Mouse + + + −
Horse + + + +
Pig − + + +
Cow − + + +
Dog − + + +
Cat − + + +
Hamster + + + +
Rat + + + +
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Acknowledgments
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Purdue University
Yung-Yi MosleyAnisa DunhamFangjia Lu
Laurent CouetilCarla Olave
Kinam Park
University of Toledo
John Turner
Bakers Trust
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Combination adjuvants
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Recent study – Joone et al. Equine Vet. J. 2015
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Group 1st dose Booster(5 weeks)
Pregnancy Abnormalovarian function
I 100 ugPZP/MFA
100 ugPZP/IFA
0/7 6/7
II 500 ugrPZP/MFA
500 ugrPZP/IFA
4/7 1/7
III MFA IFA 7/7 1/7
20/21 mares with local reactions, 3 with abscesses