Bacterial biofilms, especially those associated with implanted medical devices, are difficult to eradicate. Curli amyloid fibers are important components of the biofilms formed by the Enterobacteriaceae family. Here, we show that a human monoclonal antibody with pan-amyloid-binding activity (mAb 3H3) can disrupt biofilms formed by *Salmonella enterica* serovar Typhimurium *in vitro* and *in vivo*. The antibody disrupts the biofilm structure, enhancing biofilm eradication by antibiotics and immune cells. In mice, 3H3 injections allow antibiotic-mediated clearance of catheter-associated *S. Typhimurium* biofilms. Thus, monoclonal antibodies that bind a pan-amyloid epitope have potential to prevent or eradicate bacterial biofilms.

Sarah A. Tursi, Rama Devudu Puligedda, Paul Szabo, Lauren K. Nicastro, Amanda L. Miller, Connie Qiu, Stefania Gallucci, Norman R. Relkin, Bettina A. Buttaro, Scott K. Dessain, Çagla Tükel