Monoclonal antibodies raised against the Junín virus glycoprotein show broad reactivity and provide protection in vivo.

Monoclonal antibodies against JUNV GPC show broad reactivity and protect in vivo, with five reducing viral loads in a mouse challenge model.

• Why it matters: JUNV causes Argentine hemorrhagic fever with high fatality rates, and current therapies are limited and often ineffective after early symptoms, highlighting the need for effective antibody-based treatments.
• What they did: Thirty mouse monoclonal antibodies were generated against JUNV GPC, with 26 cross-binding various arenaviruses, nine potently neutralizing in vitro, and five significantly reducing viral loads in a mouse model; humanized versions were also produced and tested in guinea pigs.
• The result: The identified antibodies demonstrate potential for therapeutic development and vaccine design, with key amino acid sites in GPC linked to escape mutations, informing future strategies against JUNV.