Induction of castration by immunization of male dogs with recombinant gonadotropin-releasing hormone (GnRH)-canine distemper virus (CDV) T helper cell epitope p35.
Immunocastration is a considerable alternative to a surgical castration method especially in male animal species for alleviating unwanted male behaviors and characteristics. Induction of high titer of antibody specific for gonadotropin-releasing hormone (GnRH) correlates with the regression of testes. Fusion proteins composed of canine GnRH and T helper (Th) cell epitope p35 originated from canine distemper virus (CDV) F protein and goat rotavirus VP6 protein were produced in E. coli. When these fusion proteins were injected to male dogs which were previously immunized with CDV vaccine, the fusion protein of GnRH-CDV Th cell epitope p35 induced much higher antibody than that of GnRH-rotavirus VP6 protein or GnRH alone. The degeneration of spermatogenesis was also verified in the male dogs immunized with the fusion protein of GnRH-CDV Th cell epitope p35. These results indicate that canine GnRH conjugated to CDV Th cell epitope p35 acted as a strong immunogen and the antibody to GnRH specifically neutralized GnRH in the testes. This study also implies a potential application of GnRH-based vaccines for immunocastration of male pets.
Jung
Mi-Jeong
MJ
Department of Infectious Diseases, College of Veterinary Medicine, Konkuk University, Kwangjin-gu, Seoul 143-701, Korea.
Moon
Young-Chan
YC
Cho
Ik-Hyun
IH
Yeh
Jung-Yong
JY
Kim
Sun-Eui
SE
Chang
Wha-Seok
WS
Park
Seung-Young
SY
Song
Chang-Seon
CS
Kim
Hwi-Yool
HY
Park
Keun-Kyu
KK
McOrist
Steven
S
Choi
In-Soo
IS
Lee
Joong-Bok
JB
D000595:Amino Acid Sequence; D000818:Animals; D000906:Antibodies / Q000097:blood; D001483:Base Sequence; D003269:Contraception, Immunologic / Q000379:methods / Q000662:veterinary*; D004217:Distemper Virus, Canine / Q000276:immunology*; D004285:Dogs / Q000276:immunology / Q000502:physiology*; D018984:Epitopes, T-Lymphocyte / Q000276:immunology*; D005298:Fertility / Q000276:immunology; D007987:Gonadotropin-Releasing Hormone / Q000737:chemistry / Q000276:immunology*; D008297:Male; D008969:Molecular Sequence Data; D009929:Organ Size; D011994:Recombinant Proteins / Q000276:immunology; D013091:Spermatogenesis / Q000276:immunology; D006377:T-Lymphocytes, Helper-Inducer / Q000276:immunology; D013737:Testis / Q000276:immunology; D022642:Vaccines, Contraceptive / Q000276:immunology
D000906:Antibodies; D018984:Epitopes, T-Lymphocyte; D011994:Recombinant Proteins; D022642:Vaccines, Contraceptive; D007987:Gonadotropin-Releasing Hormone