Lee Yong Jae, Jo Eun Jung, Lee Hye Won, Hwang Bo Ram, Kim Yong Hyun, Park Byoung Joo, Cho Yoon Ju, Lee Young Ah, Choi In Soo, Han Jin Soo
Department of Laboratory Animal Medicine, College of Veterinary Medicine, Konkuk University, Seoul 05029, Korea.
Department of Infectious Diseases, College of Veterinary Medicine, Konkuk University, Seoul 05029, Korea.
J Vet Sci. 2019 May;20(3):e30. doi: 10.4142/jvs.2019.20.e30.
Gonadotropin-releasing hormone (GnRH) is secreted from the hypothalamus and anti-GnRH antibodies are not formed under normal conditions. However, administration an excess of recombinant GnRH protein results in the formation of anti-GnRH. We evaluated the efficacy of the recombinant typhimurium flagellin fljB (STF2)-GnRH vaccine in inducing infertility in 17 intact male cats. The first vaccination and a boosting vaccine was injected for examination. Serum was obtained from blood collected at monthly intervals and anti-GnRH antibodies and testosterone concentrations were determined. Six months after the vaccination, testicular samples are obtained and used for histological examination. Compared with sham control group, the injection groups showed an increase in anti-GnRH antibody titers and testosterone concentrations tended to be reduced in the injection groups and increased in the control group. Histological evaluations and Johnsen's testicular biopsy scores revealed testicular hypoplasia in the 2 injection groups. Consequently, normal sexual maturation with sperm production was observed in the control group. In contrast, the cats that received the GnRH vaccine showed weak (2 of 7 cats) or moderate (4 out of 7 cats) dose-dependent infertility effects. On the basis of the results, the STF2-GnRH vaccine was identified to be effective in inducing infertility in male cats. The results of this study thus indicate the possibility of immunological castration targeting feral cats.
促性腺激素释放激素（GnRH）由下丘脑分泌，在正常情况下不会形成抗GnRH抗体。然而，过量给予重组GnRH蛋白会导致抗GnRH的形成。我们评估了重组鼠伤寒鞭毛蛋白fljB（STF2）-GnRH疫苗对17只未阉割雄性猫诱导不育的效果。注射了初次疫苗和加强疫苗用于检测。每月从采集的血液中获取血清，测定抗GnRH抗体和睾酮浓度。接种疫苗6个月后，获取睾丸样本用于组织学检查。与假手术对照组相比，注射组抗GnRH抗体滴度升高，注射组睾酮浓度有降低趋势，而对照组睾酮浓度升高。组织学评估和约翰森睾丸活检评分显示，两个注射组均出现睾丸发育不全。因此，对照组观察到正常的性成熟和精子生成。相比之下，接受GnRH疫苗的猫表现出较弱（7只猫中有2只）或中度（7只猫中有4只）的剂量依赖性不育效应。基于这些结果，确定STF2-GnRH疫苗对诱导雄性猫不育有效。因此，本研究结果表明了针对野猫进行免疫去势的可能性。
