Antigenic landscape of rabies and related lyssaviruses revealed by cryo-EM.

Rabies continues to kill over 60,000 people per year despite life-saving vaccines and post-exposure treatments and costs billions of dollars in prevention and treatment. Preventing rabies deaths and reducing the global economic burden of the virus will require both developing a monoclonal antibody cocktail to replace human serum in treatment and improving rabies vaccines to elicit long-lasting protection. Here, we solve nine cryo-electron microscopy (cryo-EM) structures of neutralizing monoclonal antibodies (mAbs) in complex with the rabies virus glycoprotein (RABV-G). The nine structures span three known antigenic sites plus two additional antigenic sites, not among the five classically identified sites. We find that these antigenic sites, V and VI, are broadly cross-reactive across lyssaviruses, whereas immunodominant sites II/IV and III are rabies specific. Across the mAb panel, fusion inhibition and binding affinity correlate best with neutralization. Together, these results provide a roadmap for structure-guided vaccine and therapeutic antibody design for rabies and related lyssaviruses.