title: Antibodies directed against integration host factor mediate biofilm clearance from Nasopore.
abstract: OBJECTIVE
  Intranasal resorbable packing, such as Nasopore, is commonly used during sinus surgery despite a paucity of evidence that demonstrates clinical benefit. We theorized that Nasopore supports bacterial growth and biofilm formation. The DNABII family of bacterial nucleic acid binding proteins stabilizes the extracellular polymeric substance of the biofilm, thus protecting bacteria from host defenses and traditional antibiotics. We tested the hypothesis that use of anti-IHF antibodies in conjunction with antibiotics would enhance biofilm eradication from Nasopore.
  
  
  METHODS
  In vitro experiments.
  
  
  METHODS
  Nontypeable Haemophilus influenzae (NTHI) biofilms were grown on Nasopore. Following 24-hour incubation, biofilms were incubated for an additional 16 hours with either medium alone, naïve rabbit serum, rabbit anti-IHF serum, amoxicillin/clavulanate, or anti-IHF serum + amoxicillin/clavulanate. Computer statistics (COMSTAT) analysis was performed on images of biofilms obtained via confocal microscopy.
  
  
  RESULTS
  NTHI readily formed a biofilm on Nasopore. Treatment with amoxicillin/clavulanate alone mediated an increase in biomass by 92% to 6.63 μ(2) /μ(3) compared to incubation in sterile medium alone (3.46 μ(2) /μ(3)). Treatment with anti-IHF alone reduced the biomass by 77% to 1.29 μ(2) /μ(3) compared to incubation with naïve rabbit serum (5.53 μ(2) /μ(3)). Anti-IHF + amoxicillin/clavulanate reduced biomass by 88% to 0.66 μ(2) /μ(3) (P <0.02) compared to incubation with naïve rabbit serum.
  
  
  CONCLUSIONS
  Antibiotics alone were ineffective in eradicating NTHI biofilms that had formed on Nasopore in vitro. Anti-IHF antibodies plus amoxicillin/clavulanate therapy synergistically reduced biofilm biomass by 88%. These data support clinical studies for the use of anti-IHF combined with antibiotics to reduce biofilm formation on intranasal packing.
authors.affiliation: Department of Otolaryngology-Head and Neck Surgery, The Ohio State University, The Research Institute at Nationwide Children's Hospital, Columbus, Ohio, U.S.A.
authors.forename: Kathleyn A
authors.initials: KA
authors.lastname: Brandstetter
authors.forename: Joseph A
authors.initials: JA
authors.lastname: Jurcisek
authors.forename: Steven D
authors.initials: SD
authors.lastname: Goodman
authors.forename: Lauren O
authors.initials: LO
authors.lastname: Bakaletz
authors.forename: Subinoy
authors.initials: S
authors.lastname: Das
mesh_terms: D019980:Amoxicillin-Potassium Clavulanate Combination / Q000494:pharmacology*; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D000906:Antibodies / Q000276:immunology*; D018441:Biofilms / Q000187:drug effects*; D006193:Haemophilus influenzae / Q000187:drug effects* / Q000276:immunology / Q000502:physiology*; D034982:Integration Host Factors / Q000187:drug effects* / Q000276:immunology*; D013630:Tampons, Surgical / Q000382:microbiology*
chemical_list: D000900:Anti-Bacterial Agents; D000906:Antibodies; D034982:Integration Host Factors; D019980:Amoxicillin-Potassium Clavulanate Combination
keywords: Nasopore; anti-IHF; antibiotics; biofilms; nontypeable Haemophilus influenzae