Antimicrobial Blue Light Inactivation of Polymicrobial Biofilms

Polymicrobial biofilms, in which mixed microbial species are present, play a significant role in persistent infections. Furthermore, polymicrobial biofilms promote antibiotic resistance by allowing interspecies transfer of antibiotic resistance genes. In the present study, we investigated the effectiveness of antimicrobial blue light (aBL; 405 nm), an innovative non-antibiotic approach, for the inactivation of polymicrobial biofilms. Dual-species biofilms with Pseudomonas aeruginosa and methicillin-resistant Staphylococcus aureus (MRSA) as well as with P. aeruginosa and Candida albicans were reproducibly grown in 96-well microtiter plates or in the CDC biofilm reactor for 24 or 48 h. The effectiveness of aBL inactivation of polymicrobial biofilms was determined through colony forming assay and compared with that of monomicrobial biofilms of each species. aBL-induced morphological changes of biofilms were analyzed with confocal laser scanning microscopy (CLSM) and scanning electron microscopy (SEM). For 24-h old monomicrobial biofilms formed in 96-well microtiter plates, 6.30-log10 CFU inactivation of P. aeruginosa, 2.33-log10 CFU inactivation of C. albicans and 3.48-log10 CFU inactivation of MRSA were observed after an aBL exposure of 500 J/cm2. Under the same aBL exposure, 6.34-log10 CFU inactivation of P. aeruginosa and 3.11-log10 CFU inactivation of C. albicans were observed, respectively, in dual-species biofilms. In addition, 2.37- and 3.40-log10 CFU inactivation were obtained in MRSA and P. aeruginosa, dual-species biofilms. The same aBL treatment of the biofilms developed in the CDC-biofilm reactor for 48 h significantly decreased the viability of P. aeruginosa monomicrobial and polymicrobial biofilm when cocultured with MRSA (3.70- and 3.56-log10 CFU inactivation, respectively). 2.58-log10 CFU inactivation and 0.86-log10 CFU inactivation was detected in MRSA monomicrobial and polymicrobial biofilm when cocultured with P. aeruginosa. These findings were further supported by the CLSM and SEM experiments. Phototoxicity studies revealed a no statistically significant loss of viability in human keratinocytes after an exposure to 216 J/cm2 and a statistically significant loss of viability after 500 J/cm2. aBL is potentially an alternative treatment against polymicrobial biofilm-related infections. Future studies will aim to improve the efficacy of aBL and to investigate aBL treatment of polymicrobial biofilm-related infections in vivo.

[1]  D. Raoult,et al.  The polymicrobial nature of biofilm infection. , 2013, Clinical microbiology and infection : the official publication of the European Society of Clinical Microbiology and Infectious Diseases.

[2]  R. Hancock,et al.  Broad-Spectrum Anti-biofilm Peptide That Targets a Cellular Stress Response , 2014, PLoS pathogens.

[3]  Chuan Wang,et al.  460nm visible light irradiation eradicates MRSA via inducing prophage activation. , 2017, Journal of photochemistry and photobiology. B, Biology.

[4]  T. Dahl,et al.  Comparison of killing of gram-negative and gram-positive bacteria by pure singlet oxygen , 1989, Journal of bacteriology.

[5]  Tianhong Dai,et al.  Antimicrobial Blue Light Inactivation of Gram-Negative Pathogens in Biofilms: In Vitro and In Vivo Studies. , 2016, The Journal of infectious diseases.

[6]  G. Im,et al.  In vitro Multi-Species Biofilms of Methicillin-Resistant Staphylococcus aureus and Pseudomonas aeruginosa and Their Host Interaction during In vivo Colonization of an Otitis Media Rat Model , 2017, Front. Cell. Infect. Microbiol..

[7]  K. Rumbaugh,et al.  Synergistic Interactions of Pseudomonas aeruginosa and Staphylococcus aureus in an In Vitro Wound Model , 2014, Infection and Immunity.

[8]  John G. Anderson,et al.  Lethal effects of high-intensity violet 405-nm light on Saccharomyces cerevisiae, Candida albicans, and on dormant and germinating spores of Aspergillus niger. , 2013, Fungal biology.

[9]  J. Pemán,et al.  Activity of Amphotericin B and Anidulafungin Combined with Rifampicin, Clarithromycin, Ethylenediaminetetraacetic Acid, N-Acetylcysteine, and Farnesol against Candida tropicalis Biofilms , 2017, Journal of fungi.

[10]  G. Klug,et al.  Singlet oxygen stress in microorganisms. , 2011, Advances in microbial physiology.

[11]  T. Maisch Resistance in antimicrobial photodynamic inactivation of bacteria , 2015, Photochemical & photobiological sciences : Official journal of the European Photochemistry Association and the European Society for Photobiology.

[12]  S. Encarnación,et al.  Interspecies competition triggers virulence and mutability in Candida albicans–Pseudomonas aeruginosa mixed biofilms , 2014, The ISME Journal.

[13]  Tianhong Dai,et al.  Photodynamic therapy for localized infections--state of the art. , 2009, Photodiagnosis and photodynamic therapy.

[14]  P. Stewart,et al.  Antimicrobial activity of synthetic cationic peptides and lipopeptides derived from human lactoferricin against Pseudomonas aeruginosa planktonic cultures and biofilms , 2015, BMC Microbiology.

[15]  J. Costerton,et al.  Bacterial biofilms: a common cause of persistent infections. , 1999, Science.

[16]  Philipp Stiefel,et al.  Critical aspects of using bacterial cell viability assays with the fluorophores SYTO9 and propidium iodide , 2015, BMC Microbiology.

[17]  Deborah A. Hogan,et al.  Medically important bacterial–fungal interactions , 2010, Nature Reviews Microbiology.

[18]  Tianhong Dai,et al.  Antimicrobial blue light inactivation of pathogenic microbes: State of the art. , 2017, Drug resistance updates : reviews and commentaries in antimicrobial and anticancer chemotherapy.

[19]  S. Macgregor,et al.  Photoinactivation of Bacteria Attached to Glass and Acrylic Surfaces by 405 nm Light: Potential Application for Biofilm Decontamination , 2013, Photochemistry and photobiology.

[20]  Steven D. Brown,et al.  Reference method for broth dilution antifungal susceptibility testing of yeasts : Third informational supplement , 2008 .

[21]  Alistair J. P. Brown,et al.  A Multifunctional, Synthetic Gaussia princeps Luciferase Reporter for Live Imaging of Candida albicans Infections , 2009, Infection and Immunity.

[22]  J. Albertyn,et al.  Candida albicans and Pseudomonas aeruginosa Interaction, with Focus on the Role of Eicosanoids , 2016, Front. Physiol..

[23]  B. Peters,et al.  Polymicrobial Interactions: Impact on Pathogenesis and Human Disease , 2012, Clinical Microbiology Reviews.

[24]  Mei X. Wu,et al.  Bactericidal Property of Oregano Oil Against Multidrug-Resistant Clinical Isolates , 2018, Front. Microbiol..

[25]  Luke McNally,et al.  The biogeography of polymicrobial infection , 2015, Nature Reviews Microbiology.

[26]  Angela T. Nguyen,et al.  Interactions between Pseudomonas aeruginosa and Staphylococcus aureus during co-cultivations and polymicrobial infections , 2016, Applied Microbiology and Biotechnology.

[27]  N. Høiby,et al.  Modelling of ciprofloxacin killing enhanced by hyperbaric oxygen treatment in Pseudomonas aeruginosa PAO1 biofilms , 2018, PloS one.

[28]  Itumeleng Phyllis Molobela,et al.  Impact of bacterial biofilms: the importance of quantitative biofilm studies , 2011, Annals of Microbiology.

[29]  T. Dougherty Photodynamic therapy. , 1993, Photochemistry and photobiology.

[30]  D. Masson-Meyers,et al.  Spectrally resolved infrared microscopy and chemometric tools to reveal the interaction between blue light (470nm) and methicillin-resistant Staphylococcus aureus. , 2017, Journal of photochemistry and photobiology. B, Biology.

[31]  Maurice P. Gallagher,et al.  Light as a Broad-Spectrum Antimicrobial , 2018, Front. Microbiol..

[32]  Anália Lourenço,et al.  Critical review on biofilm methods , 2017, Critical reviews in microbiology.

[33]  T. Kielian,et al.  Infectious Dose Dictates the Host Response during Staphylococcus aureus Orthopedic-Implant Biofilm Infection , 2016, Infection and Immunity.

[34]  Clinical,et al.  Reference method for broth dilution antifungal susceptibility testing of yeasts : Approved standard , 2008 .

[35]  J. M. Goodson,et al.  Phototargeting human periodontal pathogens in vivo , 2015, Lasers in Medical Science.

[36]  W. Dunne,et al.  Bacterial Adhesion: Seen Any Good Biofilms Lately? , 2002, Clinical Microbiology Reviews.

[37]  Michael R Hamblin,et al.  Visible Blue Light is Capable of Inactivating Candida albicans and Other Fungal Species. , 2017, Photomedicine and laser surgery.

[38]  Clsi Performance Standards for Antimicrobial Susceptibility Testing: Twenty-First Informational Supplement , 2010 .

[39]  S. Rice,et al.  Biofilms: an emergent form of bacterial life , 2016, Nature Reviews Microbiology.

[40]  Tianhong Dai,et al.  Blue light for infectious diseases: Propionibacterium acnes, Helicobacter pylori, and beyond? , 2012, Drug resistance updates : reviews and commentaries in antimicrobial and anticancer chemotherapy.

[41]  M. Harriott,et al.  Importance of Candida-bacterial polymicrobial biofilms in disease. , 2011, Trends in microbiology.