Asghar Naveed, Jaafar Rita, Valko Anna, Merinder Olivia, Ljungberg Karl, Lindqvist Carl Mårten, Johansson Magnus
School of Medical Sciences, Faculty of Medicine and Health, Örebro University, Örebro, Sweden.
Scantox Sweden, Solna, Sweden.
Npj Viruses. 2025 May 23;3(1):44. doi: 10.1038/s44298-025-00129-6.
Tick-borne encephalitis (TBE) is one of the most important tick-transmitted diseases in Europe and Asia. With no specific antiviral treatment available, vaccination remains the most effective protective strategy for TBE. Unlike currently available inactivated TBE vaccines that require repeated boosters, live-attenuated vaccines could offer lifelong immunity with a single dose. Langat virus (LGTV) is a naturally attenuated strain of TBE virus (TBEV). In this study, we engineered and rescued four infectious clones (ICs) of LGTV using RNA- and DNA-based reverse genetics methods. The ICs rescued by DNA-based method showed higher genetic stability in cell culture. One of the ICs rescued by DNA-based method was further evaluated in vitro and in vivo, which exhibited growth kinetics and immune profile comparable to the LGTV strain in our laboratory. This reverse genetics platform will be utilized to introduce targeted mutations within the LGTV genome to develop a live-attenuated TBE vaccine.
蜱传脑炎（TBE）是欧亚大陆最重要的蜱传疾病之一。由于没有可用的特异性抗病毒治疗方法，疫苗接种仍然是预防TBE最有效的保护策略。与目前需要多次加强接种的灭活TBE疫苗不同，减毒活疫苗单剂量即可提供终身免疫。兰加特病毒（LGTV）是蜱传脑炎病毒（TBEV）的一种自然减毒株。在本研究中，我们使用基于RNA和DNA的反向遗传学方法构建并拯救了四个LGTV感染性克隆（IC）。基于DNA的方法拯救的IC在细胞培养中显示出更高的遗传稳定性。对基于DNA的方法拯救的其中一个IC进行了进一步的体外和体内评估，其生长动力学和免疫特性与我们实验室中的LGTV毒株相当。这个反向遗传学平台将用于在LGTV基因组中引入靶向突变，以开发一种减毒活TBE疫苗。
