Engineered antibodies for the inhibition of PRRSV entry

Porcine reproductive and respiratory syndrome virus (PRRSV) remains a major threat to the swine industry. Owing to its high genetic variability and ability to induce immune suppression, current prevention strategies, such as vaccination, offer only limited cross-protection. Other interventions, such as inactivated vaccines and passive immunization, have shown only modest, context dependent, or mainly adjunctive efficacy against PRRSV, highlighting the urgent need for more effective interventions. Viral entry is the earliest step in PRRSV infection; determining whether a productive infection can be established is important, and viral entry is considered an attractive intervention target. Owing to their high specificity, design flexibility, and engineering accessibility, antibody-based approaches are expected to enable precise blockade of viral entry across diverse PRRSV strains. This review summarizes the main entry-related targets of PRRSV and recent progress in antibody strategies for blocking viral entry. These advances support the development of more precise and adaptable antibody-based tools for PRRSV control.