TY - JOUR
T1 - Effect of Virulence Factors on the Photodynamic Inactivation of Cryptococcus neoformans
AU - Prates, Renato A.
AU - Fuchs, Beth Burgwyn
AU - Mizuno, Kazue
AU - Naqvi, Qurat
AU - Kato, Ilka T.
AU - Ribeiro, Martha S.
AU - Mylonakis, Eleftherios
AU - Tegos, George P.
AU - Hamblin, Michael R.
PY - 2013/1/18
Y1 - 2013/1/18
N2 - Opportunistic fungal pathogens may cause an array of superficial infections or serious invasive infections, especially in immunocompromised patients. Cryptococcus neoformans is a pathogen causing cryptococcosis in HIV/AIDS patients, but treatment is limited due to the relative lack of potent antifungal agents. Photodynamic inactivation (PDI) uses the combination of non-toxic dyes called photosensitizers and harmless visible light, which produces singlet oxygen and other reactive oxygen species that produce cell inactivation and death. We report the use of five structurally unrelated photosensitizers (methylene blue, Rose Bengal, selenium derivative of a Nile blue dye, a cationic fullerene and a conjugate between poly-L-lysine and chlorin(e6)) combined with appropriate wavelengths of light to inactivate C. neoformans. Mutants lacking capsule and laccase, and culture conditions that favoured melanin production were used to probe the mechanisms of PDI and the effect of virulence factors. The presence of cell wall, laccase and melanin tended to protect against PDI, but the choice of the appropriate photosensitizers and dosimetry was able to overcome this resistance.
AB - Opportunistic fungal pathogens may cause an array of superficial infections or serious invasive infections, especially in immunocompromised patients. Cryptococcus neoformans is a pathogen causing cryptococcosis in HIV/AIDS patients, but treatment is limited due to the relative lack of potent antifungal agents. Photodynamic inactivation (PDI) uses the combination of non-toxic dyes called photosensitizers and harmless visible light, which produces singlet oxygen and other reactive oxygen species that produce cell inactivation and death. We report the use of five structurally unrelated photosensitizers (methylene blue, Rose Bengal, selenium derivative of a Nile blue dye, a cationic fullerene and a conjugate between poly-L-lysine and chlorin(e6)) combined with appropriate wavelengths of light to inactivate C. neoformans. Mutants lacking capsule and laccase, and culture conditions that favoured melanin production were used to probe the mechanisms of PDI and the effect of virulence factors. The presence of cell wall, laccase and melanin tended to protect against PDI, but the choice of the appropriate photosensitizers and dosimetry was able to overcome this resistance.
UR - http://www.scopus.com/inward/record.url?scp=84872546513&partnerID=8YFLogxK
U2 - 10.1371/journal.pone.0054387
DO - 10.1371/journal.pone.0054387
M3 - Article
C2 - 23349872
AN - SCOPUS:84872546513
SN - 1932-6203
VL - 8
JO - PLoS ONE
JF - PLoS ONE
IS - 1
M1 - e54387
ER -
