Therapeutic potential of an anti-Gn glycoprotein antibody against severe fever with thrombocytopenia syndrome virus infection in A129 mice.

Abstract

Severe fever with thrombocytopenia syndrome (SFTS) is a tick-borne infectious disease transmitted by SFTS virus (also called Dabie bandavirus). This disease is endemic to East Asia, characterized by high fever, thrombocytopenia, leukopenia, and multi-organ failure, with a case fatality rate of 10% to 30%. Although SFTS virus poses a significant public health threat, no vaccines or targeted antiviral treatments are currently available. In this study, we investigated the therapeutic potential of Ab10, an antibody derived from an SFTS virus-infected patient, through a series of in vitro and in vivo experiments. Initially, we confirmed Ab10's ability to cross-neutralize SFTS viruses with multiple genotypes in vitro, followed by an in vivo efficacy assessment. Utilizing the A129 mouse model, we evaluated survival rates and viral titers following challenge with SFTSV and subsequent post-infection treatment with the anti-Gn monoclonal antibody Ab10. Our findings demonstrate a 100% survival rate in Ab10-treated groups, supporting its protective effect. Furthermore, Ab10 administration significantly decreased viral RNA levels in major target organs such as the liver, lungs, spleen, and lymph nodes compared to untreated controls. These results suggest that Ab10 could serve as a promising therapeutic option for SFTS and contribute to the development of effective antiviral treatments.