Biomedical Sciences Department, Defence Science and Technology Laboratory, Porton Down, Salisbury, Wiltshire, SP4 0JQ, UK.
Virol J. 2009 Nov 19;6:206. doi: 10.1186/1743-422X-6-206.
There is currently a requirement for antiviral therapies capable of protecting against infection with Venezuelan equine encephalitis virus (VEEV), as a licensed vaccine is not available for general human use. Monoclonal antibodies are increasingly being developed as therapeutics and are potential treatments for VEEV as they have been shown to be protective in the mouse model of disease. However, to be truly effective, the antibody should recognise multiple strains of VEEV and broadly reactive monoclonal antibodies are rarely and only coincidentally isolated using classical hybridoma technology.
In this work, methods were developed to reliably derive broadly reactive murine antibodies. A phage library was created that expressed single chain variable fragments (scFv) isolated from mice immunised with multiple strains of VEEV. A broadly reactive scFv was identified and incorporated into a murine IgG2a framework. This novel antibody retained the broad reactivity exhibited by the scFv but did not possess virus neutralising activity. However, the antibody was still able to protect mice against VEEV disease induced by strain TrD when administered 24 h prior to challenge.
A monoclonal antibody possessing reactivity to a wide range of VEEV strains may be of benefit as a generic antiviral therapy. However, humanisation of the murine antibody will be required before it can be tested in humans.
目前需要能够预防委内瑞拉马脑炎病毒（VEEV）感染的抗病毒疗法，因为目前尚无许可的疫苗供一般人群使用。单克隆抗体作为治疗药物越来越受到关注，并且可能是 VEEV 的治疗方法，因为它们已被证明在疾病的小鼠模型中具有保护作用。然而，为了真正有效，抗体应该识别多种 VEEV 株，而使用经典的杂交瘤技术很少且仅偶然分离出广泛反应性的单克隆抗体。
在这项工作中，开发了可靠地衍生广泛反应性鼠抗体的方法。创建了一个噬菌体文库，该文库表达了从小鼠免疫多种 VEEV 株中分离出的单链可变片段（scFv）。鉴定出一种广泛反应的 scFv，并将其整合到鼠 IgG2a 框架中。该新型抗体保留了 scFv 表现出的广泛反应性，但没有病毒中和活性。然而，当在挑战前 24 小时给予该抗体时，该抗体仍能保护小鼠免受由 TrD 株引起的 VEEV 疾病。
具有广泛反应性的单克隆抗体可能作为通用抗病毒疗法有益。然而，在对人类进行测试之前，需要对鼠抗体进行人源化。
