Complement regulator C4BP binds to Staphylococcus aureus surface proteins SdrE and Bbp inhibiting bacterial opsonization and killing.

Staphylococcus aureus is a premier human pathogen and the most common cause of osteoarticular, wound, and implanted device infections. We recently demonstrated S. aureus efficiently binds the classical complement regulator C4b-binding protein (C4BP) inhibiting antibody-initiated complement-mediated opsonization.