Antibodies against the DNABII protein integration host factor (IHF) inhibit sinus implant biofilms

Objectives Chronic rhinosinusitis is a common, costly condition often treated with endoscopic sinus surgery and intraoperative placement of intranasal sinus implant materials. Whereas these materials aid in postoperative healing, they also support bacterial biofilm formation and thus contribute to negative outcomes. This study examined pretreatment of sinus implant materials with antibody against an essential bacterial biofilm structural component, the DNABII family of DNA-binding proteins, as a strategy to prevent biofilm formation. Methods Sinus implant materials were equilibrated in immunoglobulin G (IgG)-enriched antiserum against the DNABII protein integration host factor (IHF), individually or in combination with amoxicillin-clavulanate prior to inoculation with nontypeable Haemophilus influenzae (NTHI), a predominant pathogen of chronic rhinosinusitis. After 16 hours, the bacterial burden was quantitated and compared to pretreatment with saline, IgG-enriched naive serum, or amoxicillin-clavulanate alone. Results NTHI readily formed biofilms on all three materials in vitro. However, pretreatment of each material with IgG-enriched anti-IHF resulted in a significant decrease in bacterial burden compared to controls (P <= 0.05). Moreover, a significant and synergistic outcome was achieved with a cocktail of anti-IHF plus amoxicillin-clavulanate (P <= 0.05) with complete inhibition of NTHI biofilm formation on all three materials. Conclusions Biofilm formation was well supported in vitro on three sinus implant materials that vary in composition and resorption characteristics; however, pretreatment of each with DNABII protein targeted antibodies in combination with a previously ineffective antibiotic was highly effective to prevent the formation NTHI biofilms. These data demonstrate the potential for clinical utility of pretreatment of sinus implant and additional surgical materials with anti-DNABII antibodies. Level of Evidence NA Laryngoscope, 2019