Nicklin Amanda M, McEntee Margaret C, Ledbetter Eric C
Cornell University, College of Veterinary Medicine, Department of Clinical Sciences, Ithaca, NY 14853, United States.
Cornell University, College of Veterinary Medicine, Department of Clinical Sciences, Ithaca, NY 14853, United States.
Vet Microbiol. 2014 Dec 5;174(3-4):433-437. doi: 10.1016/j.vetmic.2014.10.029. Epub 2014 Nov 3.
Latent canine herpesvirus-1 (CHV-1) infections are common in domestic dogs, but stimuli causing viral reactivation and recrudescent disease are poorly understood. Immunosuppressive pharmaceuticals are currently the only experimentally established triggers for recurrent ocular CHV-1 infection in dogs; however, ocular CHV-1 shedding has been reported clinically following strontium-90 beta radiotherapy of the ocular surface and it has been speculated that radiotherapy can directly induce viral reactivation. Strontium-90 is used as a beta radiation source for the treatment of a variety of neoplastic and immune-mediated canine ocular surface diseases. In the present study, the effects of ocular surface strontium-90 beta radiotherapy in dogs latently infected with CHV-1 were evaluated. Ten mature dogs with experimentally induced latent CHV-1 infections were randomly divided into two groups: one group received a single fraction 50 Gy radiation dose in one application from a strontium-90 ophthalmic applicator and the second group received sham radiotherapy. Dogs were then monitored for 45 days for recurrent ocular CHV-1 infection using clinical and virological outcome measures. Clinical ophthalmic examinations, ocular sample CHV-1 PCR assays, and serum CHV-1 virus neutralizing antibody assays were performed at specified intervals. No abnormalities suggestive of recurrent CHV-1 ocular disease were observed on clinical examination in any dog during the study. Ocular viral shedding was not detected and CHV-1 virus neutralizing titers remained stable in all dogs. A single fraction 50 Gy radiation dose administered to the ocular surface by strontium-90 beta radiotherapy did not result in detectable recurrent ocular CHV-1 infection in mature dogs with experimentally induced latent infection.
犬疱疹病毒1型（CHV-1）潜伏感染在犬类中很常见，但导致病毒重新激活和复发疾病的刺激因素却知之甚少。免疫抑制药物是目前唯一经实验证实可引发犬复发性眼部CHV-1感染的诱因；然而，临床报告显示，眼部表面进行锶-90β放射治疗后会出现眼部CHV-1脱落，据推测放射治疗可直接诱导病毒重新激活。锶-90用作β辐射源，用于治疗多种犬类眼部肿瘤和免疫介导性疾病。在本研究中，评估了眼部表面锶-90β放射治疗对潜伏感染CHV-1的犬的影响。十只经实验诱导发生CHV-1潜伏感染的成年犬被随机分为两组：一组使用锶-90眼科敷贴器一次性给予50 Gy的单剂量辐射，另一组接受假放射治疗。然后，使用临床和病毒学结果指标对犬进行45天的监测，以观察是否发生复发性眼部CHV-1感染。在特定时间间隔进行临床眼科检查、眼部样本CHV-1 PCR检测和血清CHV-1病毒中和抗体检测。在研究期间，任何犬的临床检查均未观察到提示CHV-1眼部疾病复发的异常情况。未检测到眼部病毒脱落，所有犬的CHV-1病毒中和滴度保持稳定。对于经实验诱导发生潜伏感染的成年犬，通过锶-90β放射治疗对眼部表面给予50 Gy的单剂量辐射，并未导致可检测到的复发性眼部CHV-1感染。
