Recombinant Expression and Immunogenicity Verification of Dabie Bandavirus Proteins Gn and Gc

Xiuyu Lou¹Haiyan Mao¹Yihan Lou¹Yi Sun¹Feng Wang¹Minjie Wang²Lijun Zhang³Zhihan Fang⁴Hao Yan^1*Zhang Huijun^2*

• ¹Zhejiang Center for Disease Control and Prevention (Zhejiang CDC), Hangzhou, China
• ²Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
• ³Fudan University Minhang Hospital, Shanghai, China
• ⁴Yangpu Hospital Affiliated to Tongji University School of Medicine, Shanghai, China

The Dabie bandavirus (DBV) , a newly identified pathogen transmitted to humans via ticks bites, is the etiologic agent of severe fever with thrombocytopenia syndrome (SFTS). This disease is associated with a high mortality rate and constitutes a substantial threat to global public health. In this study, genetic engineering techniques were employed for the recombinantly expression of DBV envelope proteins Gn and Gc, followed by systematic evaluation of their immunogenicity and antigenicity. The recombinant plasmids pET15b-Gn and pET15b-Gc were constructed, expressed, and purified, and a series of experiments were conducted to prepare rabbit anti-rGn-IgG and anti-rGc-IgG antibodies. Additionally, the antigenicity of the recombinant proteins was characterized. The results demonstrated successful induction, expression, and purification of the rGn and rGc proteins with molecular weights consistent with theoretical expectations. Following four rounds of immunization in New Zealand white rabbits, the titers of rGn-IgG and rGc-IgG antibodies reached 1:512,000 and 1:256,000, respectively. The recombinant proteins rGn and rGc exhibited no significant cross-reactivity with prevalent arboviruses. The detection rates of DBV IgM antibody-positive samples using rGn and rGc-coated plates were 84.21% and 89.47%, respectively.This study confirmed that the prokaryotically expressed DBV Gn and Gc proteins possess favorable immunogenicity, addressing the critical knowledge gap in evaluating of the immunogenic efficacy of prokaryotically expressed Gn and Gc. Currently, research on DBV's pathogenic mechanisms, protein structure, and functions remains limited, and this findings provide a foundation for the development of DBV-related vaccines and drugs.