title: Incorporation of secretory immunoglobulin A into biofilms can decrease their resistance to ciprofloxacin.
abstract: Extracellular matrices utilized by biofilms growing on inert surfaces are generally produced entirely by the bacteria growing within those biofilms, whereas symbiotic (mutualistic) biofilms growing in or on a wide range of plants and animals utilize host-derived macromolecules, such as mucoid substances, as components of their extracellular matrix. Incorporation of host-derived molecules may have a profound effect on the resistance to antibiotics of symbiotic biofilms, which may have important implications for medicine and biology. As an initial probe of the potential effects of host-derived molecules in the extracellular matrix on the sensitivity of biofilms to antibiotics, an in vitro model was used to evaluate the effects of ciprofloxacin on biofilms grown in the presence and absence of SIgA, a host-derived glycoprotein associated with biofilms in the mammalian gut. In five out of six strains of Escherichia coli tested, the incorporation of SIgA into the biofilms apparently reduced the resistance of the bacteria to ciprofloxacin. On the other hand, SIgA generally increased the resistance of planktonic bacteria to ciprofloxacin, perhaps due in part to the SIgA-mediated aggregation of the bacteria. These findings suggest that incorporation of host-derived molecules into the extracellular matrix of symbiotic biofilms might profoundly alter the properties of those biofilms, including the resistance of those biofilms to antibiotics.
authors.affiliation: Department of Surgery, Duke University Medical Center, Durham, North Carolina 27710, USA.
authors.forename: Yu-Huei
authors.initials: YH
authors.lastname: Lee
authors.forename: Kuei-Ying
authors.initials: KY
authors.lastname: Su
authors.forename: Aaron
authors.initials: A
authors.lastname: Wyse
authors.forename: Andrew
authors.initials: A
authors.lastname: Barbas
authors.forename: Daniel
authors.initials: D
authors.lastname: Palestrandt
authors.forename: Karl
authors.initials: K
authors.lastname: Shieh
authors.forename: Mary Lou
authors.initials: ML
authors.lastname: Everett
authors.forename: Aditya
authors.initials: A
authors.lastname: Devalapalli
authors.forename: Paul E
authors.initials: PE
authors.lastname: Orndorff
authors.forename: R Randal
authors.initials: RR
authors.lastname: Bollinger
authors.forename: William
authors.initials: W
authors.lastname: Parker
mesh_terms: D000818:Animals; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D018441:Biofilms / Q000187:drug effects*; D002939:Ciprofloxacin / Q000494:pharmacology*; D003470:Culture Media / Q000737:chemistry; D024881:Drug Resistance, Bacterial / Q000187:drug effects* / Q000276:immunology*; D004926:Escherichia coli / Q000187:drug effects / Q000502:physiology; D006801:Humans; D007071:Immunoglobulin A, Secretory / Q000494:pharmacology*; D051379:Mice; D008892:Milk / Q000276:immunology
chemical_list: D000900:Anti-Bacterial Agents; D003470:Culture Media; D007071:Immunoglobulin A, Secretory; D002939:Ciprofloxacin