A single residue in the Gc protein dictates neutralization sensitivity and virulence in SFTSV.

A single residue, Arg577 in Gc protein, determines SFTSV's neutralization sensitivity, replication fitness, and virulence in different strains.

• Why it matters: Understanding the molecular basis of SFTSV pathogenicity and immune evasion is crucial for developing effective vaccines and therapies against this WHO priority pathogen.
• What they did: Researchers isolated Gc-specific monoclonal antibodies H2, H4, and H12, and used mutational analysis and reverse genetics to identify Arg577 as essential for antibody binding, viral replication, and virulence modulation across strains.
• The result: Mutating Arg577 altered neutralization susceptibility and viral fitness, with the combination of H2 and H12 antibodies providing broad protection, highlighting Arg577 as a key target for therapeutic strategies.