title: Sonodynamic inactivation of Gram-positive and Gram-negative bacteria using a Rose Bengal-antimicrobial peptide conjugate.
abstract: Combating antimicrobial resistance is one of the most serious public health challenges facing society today. The development of new antibiotics or alternative techniques that can help combat antimicrobial resistance is being prioritised by many governments and stakeholders across the globe. Antimicrobial photodynamic therapy is one such technique that has received considerable attention but is limited by the inability of light to penetrate through human tissue, reducing its effectiveness when used to treat deep-seated infections. The related technique sonodynamic therapy (SDT) has the potential to overcome this limitation given the ability of low-intensity ultrasound to penetrate human tissue. In this study, a Rose Bengal-antimicrobial peptide conjugate was prepared for use in antimicrobial SDT (ASDT). When Staphylococcus aureus and Pseudomonas aeruginosa planktonic cultures were treated with the conjugate and subsequently exposed to ultrasound, 5 log and 7 log reductions, respectively, in bacterial numbers were observed. The conjugate also displayed improved uptake by bacterial cells compared with a mammalian cell line (P ≤ 0.01), whilst pre-treatment of a P. aeruginosa biofilm with ultrasound resulted in a 2.6-fold improvement in sensitiser diffusion (P ≤ 0.01). A preliminary in vivo experiment involving ASDT treatment of P. aeruginosa-infected wounds in mice demonstrated that ultrasound irradiation of conjugate-treated wounds affects a substantial reduction in bacterial burden. Combined, the results obtained from this study highlight ASDT as a targeted broad-spectrum novel modality with potential for the treatment of deep-seated bacterial infections.
authors.affiliation: Biomedical Sciences Research Institute, University of Ulster, Coleraine BT52 1SA, UK.
authors.forename: David
authors.initials: D
authors.lastname: Costley
authors.affiliation: Biomedical Sciences Research Institute, University of Ulster, Coleraine BT52 1SA, UK.
authors.forename: Heather
authors.initials: H
authors.lastname: Nesbitt
authors.affiliation: Biomedical Sciences Research Institute, University of Ulster, Coleraine BT52 1SA, UK.
authors.forename: Nigel
authors.initials: N
authors.lastname: Ternan
authors.affiliation: Biomedical Sciences Research Institute, University of Ulster, Coleraine BT52 1SA, UK.
authors.forename: James
authors.initials: J
authors.lastname: Dooley
authors.affiliation: Wellman Center for Photomedicine, Massachusetts General Hospital, Boston, MA 02114, USA; Department of Dermatology, Harvard Medical School, Boston, MA 02115, USA.
authors.forename: Ying-Ying
authors.initials: YY
authors.lastname: Huang
authors.affiliation: Wellman Center for Photomedicine, Massachusetts General Hospital, Boston, MA 02114, USA; Department of Dermatology, Harvard Medical School, Boston, MA 02115, USA.
authors.forename: Michael R
authors.initials: MR
authors.lastname: Hamblin
authors.affiliation: Biomedical Sciences Research Institute, University of Ulster, Coleraine BT52 1SA, UK.
authors.forename: Anthony P
authors.initials: AP
authors.lastname: McHale
authors.affiliation: Biomedical Sciences Research Institute, University of Ulster, Coleraine BT52 1SA, UK. Electronic address: j.callan@ulster.ac.uk.
authors.forename: John F
authors.initials: JF
authors.lastname: Callan
mesh_terms: D000818:Animals; D000890:Anti-Infective Agents / Q000494:pharmacology*; D023181:Antimicrobial Cationic Peptides / Q000494:pharmacology*; D058491:Bacterial Load; D004195:Disease Models, Animal; D004203:Disinfection / Q000379:methods; D005456:Fluorescent Dyes / Q000494:pharmacology*; D008807:Mice, Inbred BALB C; D011550:Pseudomonas aeruginosa / Q000187:drug effects / Q000528:radiation effects*; D012395:Rose Bengal / Q000494:pharmacology*; D013211:Staphylococcus aureus / Q000187:drug effects / Q000528:radiation effects*; D000069453:Ultrasonic Waves; D014946:Wound Infection / Q000188:drug therapy / Q000382:microbiology
chemical_list: D000890:Anti-Infective Agents; D023181:Antimicrobial Cationic Peptides; D005456:Fluorescent Dyes; D012395:Rose Bengal
keywords: Antimicrobial; Peptide; Sensitiser; Sonodynamic therapy