Photodynamic treatment (PDT) has been proposed as a new approach for inactivation of biofilms associated with medical devices that are resistant to chemical additives or biocides. In this study, we evaluated the antimicrobial activity of merocyanine 540 (MC 540), a photosensitizing dye that is used for purging malignant cells from autologous bone marrow grafts, against Staphylococcus epidermidis biofilms. Effect of the combined photodynamic action of MC 540 and 532 nm laser was investigated on the viability and structure of biofilms of two Staphylococcus epidermidis strains, RP62A and 1457. Significant inactivation of cells was observed when biofilms were exposed to MC 540 and laser simultaneously. The effect was found to be light dose-dependent but S. epidermidis 1457 biofilm proved to be slightly more susceptible than S. epidermidis RP62A biofilm. Furthermore, significant killing of both types of cells was attained even when a fixed light dose was delivered to the biofilms. Confocal laser scanning microscope (CLSM) analysis indicated damage to bacterial cell membranes in photodynamically treated biofilms, while disruption of PDT-treated biofilm was confirmed by scanning electron microscopy (SEM). (Int J Artif Organs 2008; 31: 848–57)
HarraghyN., SeilerS., JacobsK., HannigM., MengerM.D., HerrmannM.Advances in in vitro and in vivo models for studying the staphylococcal factors involved in implant infections. Int J Artif Organs2006; 29: 368–78.
ArciolaC.R., AlviF.I., AnY.H., CampocciaD., MontanaroL.Implant infection and infection resistant materials: a mini review. Int J Artif Organs2005; 28: 1119–25. Review.
5.
VadyvalooV., OttoM.Molecular genetics of Staphylococcus epidermidis biofilms on indwelling medical devices. Int. J Artif Organs2005; 281069–78.
6.
CostertonJ.W., MontanaroL., ArciolaC.R.Bacterial communications in implant infections: a target for an intelligence war. Int J Artif Organs2007; 30: 757–63. Review.
7.
CostertonJ.W., MontanaroL., ArciolaC.R.Biofilm in implant infections: its production and regulation. Int J Artif Organs2005; 28: 1062–8.
8.
VisaiL., ArciolaC.R., PietrocolaG., RindiS., OliveroP., SpezialeP.Staphylococcus biofilm components as targets for vaccines and drugs. Int J Artif Organs2007; 30: 813–9. Review.
9.
ArciolaC.R.Bacterial gangs attack implants. Int J Artif Organs2007; 30: 755–6.
10.
MackD., RohdeH., HarrisL.G., DaviesA.P., HorstkotteM.A., KnoblochJ.K.Biofilm formation in medical device-related infection. Int J Artif Organs2006; 29: 343–59.
11.
von EiffC., ArciolaC.R., MontanaroL., BeckerK., CampocciaD.Emerging Staphylococcus species as new pathogens in implant infections. Int J Artif Organs2006; 29: 360–7.
12.
BaldassarriL., MontanaroL., CretiR., ArciolaC.R.Underestimated collateral effects of antibiotic therapy in prosthesis-associated bacterial infections. Int J Artif Organs2007; 30: 786–91.
13.
ChokrA., WatierD., EleaumeH., PangonB., GhnassiaJ.C., MackD., and JabbouriS.Correlation between biofilm formation and production of polysaccharide intercellular adhesin in clinical isolates of coagulase-negative staphylococci. Int J Med Microbiol2006; 296: 381–8.
14.
MahT.F., and O' TooleG.A.Mechanisms of biofilm resistance to antimicrobial agents. Trends Microbiol2001; 9: 34–9.
15.
CercaN., JeffersonK.K., OliveiraR., PierG.B., AzeredoJ.Comparative Antibody-Mediated Phagocytosis of Staphylococcus epidermidis Cells Grown in a Biofilm or in the Planktonic State. Infect Immun2006; 74: 4849–55.
16.
CostertonJ.W., StewartP.S., and GreenbergE.P.Bacterial biofilms: a common cause of persistent infections. Science1999; 284: 1318–22.
17.
WuJ.A., KusumaC., MondJ.J., Kokai-KunJ.F.Lysostaphin disrupts Staphylococcus aureus and Staphylococcus epidermidis biofilms on artificial surfaces. Antimicrob Agents Chemother2003; 47: 3407–14.
18.
WainwrightM., KentB.C.Photosensitising agents – circumventing resistance and breaking down biofilms: a review. Int Biodeterior Biodegradation2004; 53: 119–26.
19.
JoriG.Photodynamic therapy of microbial infections: state of the art and perspectives. J Environ Pathol Toxicol Oncol2006; 25: 505–19.
20.
WilsonM.Lethal photosensitisation of oral bacteria and its potential application in the photodynamic therapy of oral infections. Photochem Photobiol Sci2004; 3: 412–8.
21.
WoodS., NattressB., KirkhamJ., ShoreR., BrookesS., GriffithsJ., RobinsonC.An in vitro study of the use of photodynamic therapy for the treatment of natural oral plaque biofilms formed in vivo. J Photochem Photobiol B;1999; 50: 1–7.
22.
WoodS., MetcalfD., DevineD., RobinsonC.Erythrosine is a potential photosensitizer for the photodynamic therapy of oral plaque biofilms. J Antimicrob Chemother2006; 57: 680–4.
GadF., ZahraT., HasanT., HamblinM.R.Effects of growth phase and extracellular slime on photodynamic inactivation of gram-positive pathogenic bacteria. Antimicrob Agents Chemother2004; 48: 2173–8.
25.
FeixJ.B., KalyanaramaB., ChignellC.D., HallR.D.Direct observation of singlet oxygen production by merocyanine 540 associated with phosphatidylcholine liposomes. J Biol Chem1998; 263: 17247–50.
26.
KalyanaramanB., FeixJ.F., SiebertF., ThomasJ.P., GirottiA.W.Photodynamic action of merocyanine 540 on artificial and natural cell membranes: Involvement of singlet molecular oxygen. Proc Natl Acad Sci USA1987; 84: 2999–3003.
27.
GaffneyD.K., SieberF.Merocyanine 540-sensitized photoinactivation of soluble and membrane-bound enzymes in L1210 leukemia cells. Cancer Res1990; 50: 7765–9.
28.
MeagherR.C., SieberF., SpivakJ.L.Susceptibility to merocyanine 540-mediated photosensitization: a differentiation marker on murine hematopoietic progenitor cells. J Cell Physiol1983; 116: 118–24.
29.
SieberF.Marrow purging by merocyanine 540-mediated photolysis. Bone Marrow Transplant1987; 2: 29–33.
30.
SieberF., SpivakJ.L., SutcliffeA.M.Selective killing of leukemic cells by merocyanine 540-mediated photosensitization. Proc Natl Acad Sci USA1984; 81: 7584–7.
31.
MartinL.S., GruegerG.J., OrloffS.L., SieberF.Dyemediated photolysis of HIV-1 and HIV-infected cells. J Cell Biochem Suppl1989; 13B: 282.
LinH.Y., ChenC.T., HuangC.T.Use of merocyanine 540 for photodynamic inactivation of Staphylococcus aureus planktonic and biofilm cells. Appl Environ Microbiol2004; 70: 6453–8.
34.
DunneW.M.Jr., SlaterW.A.Antimicrobial activity of merocyanine 540: a photosensitizing dye. Diagn Microbiol Infect Dis1998; 32: 101–5.
35.
FreemanD.J., FalkinerF.R., and KeaneC.T.New method for detecting slime production by coagulase negative staphylococci. J Clin Pathol1989; 42: 872–4.
36.
ChristensenG.D., SimpsonW.A., YoungerJ.J., BaddourL.M., BarrettF.F., MeltonD.M., and BeacheyE.H.Adherence of coagulase negative staphylococci to plastic tissue culture plates: a quantitative model for the adherence of staphylococci to medical devices. J Clin Microbiol1985; 22: 996–1006.
37.
PervaizS.Reactive oxygen-dependent production of novel photochemotherapeutic agents. FASEB J2001; 15: 612–7.
CostertonW., VeehR., ShirtliffM., PasmoreM., PostC., EhrlichG.The application of biofilm science to the study and control of chronic bacterial infections. J Clin Invest2003; 112: 1466–77.
40.
ZimmerliW., TrampuzA., and OchsnerP.E.Prosthetic-joint infections. N Engl J Med2004; 351: 1645–54.
41.
GillS.R., FoutsD.E., ArcherG.L.Insights on evolution of virulence and resistance from the complete genome analysis of an early methicillin-resistant Staphylococcus aureus strain and a biofilm-producing methicillin-resistant Staphylococcus epidermidis strain. J Bacteriol2005; 187: 2426–38.
42.
RuppM.E., UlphaniJ.S., FeyP.D., MackD.Characterization of Staphylococcus epidermidis polysaccharide intercellular adhesin/hemagglutinin in the pathogenesis of intravascular catheter-associated infection in a rat model. Infect Immun1999; 67: 2656–9.
43.
Boyle-VavraS., LabischinskiH., EbertC.C., EhlertK., and DaumR.S.A spectrum of changes occurs in peptidoglycan composition of glyco-peptide-intermediate clinical Staphylococcus aureus isolates. Antimicrob Agents Chemother2001; 45: 280–7.
44.
GulliyaK.S., PervaizS., DowbenR.M., and MatthewsJ.L.Tumor cell specific dark cytotoxicity of light-exposed merocyanine 540: implications for systemic therapy without light. Photochem Photobiol1990; 52: 831–8.
45.
PervaizS.Reactive oxygen-dependent production of novel photochemotherapeutic agents. FASEB J2001; 15: 612–7.
