Bukar Alhaji Modu, Jesse Faez Firdaus Abdullah, Abdullah Che Azurahanim Che, Noordin Mustapha M, Lawan Zaharaddeen, Mangga Hassana Kyari, Balakrishnan Krishnan Nair, Azmi Mohd-Lila Mohd
Department of Pathology and Microbiology, Faculty of Veterinary Medicine, Universiti Putra Malaysia, Serdang 43400, Selangor, Malaysia.
Department of Science Laboratory Technology, School Agriculture and Applied Sciences, Ramat Polytechnic Maiduguri, Maiduguri 1070, Borno, Nigeria.
Vaccines (Basel). 2021 Nov 17;9(11):1341. doi: 10.3390/vaccines9111341.
Orf virus (ORFV), the prototype species of the parapoxvirus genus, is the causative agent of contagious ecthyma, an extremely devastating skin disease of sheep, goats, and humans that causes enormous economic losses in livestock production. ORFV is known for its ability to repeatedly infect both previously infected and vaccinated sheep due to several immunomodulatory genes encoded by the virus that temporarily suppress host immunity. Therefore, the development of novel, safe and effective vaccines against ORFV infection is an important priority. Although, the commercially licensed live-attenuated vaccines have provided partial protection against ORFV infections, the attenuated viruses have been associated with major safety concerns. In addition to safety issues, the persistent reinfection of vaccinated animals warrants the need to investigate several factors that may affect vaccine efficacy. Perhaps, the reason for the failure of the vaccine is due to the long-term adaptation of the virus in tissue culture. In recent years, the development of vaccines against ORFV infection has achieved great success due to technological advances in recombinant DNA technologies, which have opened a pathway for the development of vaccine candidates that elicit robust immunity. In this review, we present current knowledge on immune responses elicited by ORFV, with particular attention to the effects of the viral immunomodulators on the host immune system. We also discuss the implications of strain variation for the development of rational vaccines. Finally, the review will also aim to demonstrate future strategies for the development of safe and efficient vaccines against ORFV infections.
羊口疮病毒（ORFV）是副痘病毒属的原型种，是传染性脓疱性皮炎的病原体，这是一种对绵羊、山羊和人类极具破坏性的皮肤病，会给畜牧业生产造成巨大经济损失。ORFV以其能够反复感染先前感染过和接种过疫苗的绵羊而闻名，这是因为该病毒编码的几个免疫调节基因会暂时抑制宿主免疫力。因此，开发新型、安全有效的抗ORFV感染疫苗是一项重要的优先任务。尽管商业许可的减毒活疫苗已提供了部分抗ORFV感染的保护，但减毒病毒存在重大安全隐患。除安全问题外，接种疫苗动物的持续再感染使得有必要研究可能影响疫苗效力的几个因素。也许，疫苗失败的原因是病毒在组织培养中的长期适应性。近年来，由于重组DNA技术的技术进步，抗ORFV感染疫苗的开发取得了巨大成功，这为开发能引发强大免疫力的候选疫苗开辟了一条途径。在这篇综述中，我们介绍了关于ORFV引发的免疫反应的现有知识，特别关注病毒免疫调节剂对宿主免疫系统的影响。我们还讨论了毒株变异对合理疫苗开发的影响。最后，本综述还旨在展示抗ORFV感染安全高效疫苗开发的未来策略。
