Development of a neutralization assay and bioluminescent imaging mouse model for Dehong virus (DEHV) using a pseudovirus system

Dehong virus (DEHV) is an emerging filamentous virus of considerable interest. However, research involving DEHV remains limited, and no suitable models exist to investigate its pathogenicity or transmission. In this study, we developed an <i>in vitro</i> neutralization assay to detect DEHV-neutralizing antibodies, as well as an <i>in vivo</i> bioluminescent imaging mouse model based on a pseudovirus system. Our results confirmed that DEHV utilizes the Niemann-Pick disease, type C1 (NPC1) receptor for cellular entry. Additionally, the neutralization assay demonstrated that DEHV antiserum does not exhibit neutralizing activity against Mengla or Marburg viruses. This pseudovirus-based system provides a valuable platform for studying DEHV biology and evaluating therapeutic interventions.IMPORTANCEBats serve as natural reservoirs for diverse filoviruses across Africa, Europe, and East Asia; numerous strains circulate within these populations. Recently, Chinese researchers identified Dehong virus (DEHV), a novel filovirus carried by bats in China. However, the mechanisms underlying the pathogenicity and transmission of DEHV remain poorly understood. Similar to Ebola virus and Marburg virus (MARV), DEHV uses the Niemann-Pick disease, type C1 (NPC1) receptor for host cell invasion. In this study, we utilized a well-established in <i>vitro</i> neutralization assay to confirm that DEHV antiserum lacks neutralizing activity against Mengla and MARV pseudoviruses. Furthermore, we developed an innovative in <i>vivo</i> bioluminescent imaging mouse model using DEHV pseudovirus, which offers a visually intuitive and efficient platform for evaluating antiviral therapies and vaccine candidates. This model has considerable potential for advancing research into DEHV pathogenesis and treatment strategies.