Monitoring the effect of photodynamic therapy oral infection with Candida albicans in immunosuppressed mice by bioluminescence imaging

• Grant number: 14/25772-9
• Support type: Scholarships abroad - Research Internship - Doctorate
• Effective date (Start): July 01, 2015
• Effective date (End): December 31, 2015
• Field of knowledge: Health Sciences - Dentistry
• Principal Investigator: Antonio Olavo Cardoso Jorge
• Grantee: Fernanda Freire
• Supervisor abroad: Michael R. Hamblin
• Home Institution: Instituto de Ciência e Tecnologia (ICT). Universidade Estadual Paulista (UNESP). Campus de São José dos Campos. São José dos Campos , SP, Brazil
• Local de pesquisa : Massachusetts General Hospital, United States
• Associated to the scholarship: 13/22897-2 - Antimicrobial action of photodynamic therapy in gene expression in Candida albicans biofilms, BP.DR

Abstract

Species of the genus Candida express virulence factors that, associated with immunosuppression and other risk factors, can cause different manifestations of oral candidiasis. The treatment of mucosal infections causedby Candida and the elucidation of the disease process have proven challenging.Therefore, the study of experimentally induced oral candidiasis in mice is usefulto clarify the etiopathology of this condition, to improve diagnosis, and to identifynew therapeutic options, since the disease process in these animals is similar tothat seen in human candidiasis lesions. Although many researchers have usedphotodynamic therapy (PDT) to kill fungi in vitro and the use of this approach invivo in animal models of infection has seldom been reported. This study willevaluate the effects of PDT on oral candidiasis in immunosuppressed mice bybioluminescence imaging. A luciferase-expressing Candida albicans strain (CEC749) will be used. This yeast is engineered to emit light, permitting the progressof infection to be monitored in both space and time with a low light imagingcharge-coupled device (CCD) camera. In order to facilitate the monitoringprocess, a procedure that uses genetically engineered bioluminescent yeast anda light-sensitive imaging system was developed to permit real-time visualizationof infections. The phenothiazinium salts toluidine blue O (TBO) (T3260- 5G;Sigma, St. Louis, MO), methylene blue (MB) (M9140-25G; Sigma), and newmethylene blue (NMB) (556416-1G; Sigma) will be used as the photosensitizers(PS) in the study. Eighty immunosuppressed adult male BALB/c mice (CharlesRiver Laboratories, Wilmington, MA) with oral candidiasis will be used and dividedinto four groups: a) P+L+: sensitization with PS and light irradiation (n=30); b)P+L-: only treatment with PS (n=30); c) P-L+: only light irradiation (n=10), and d)P-L-: control group not submitted to sensitization with PS or light irradiation(n=10). Ten mice per PS will be used for the P+L+ and P+L- groups. After treatment, the effects of PDT will be analyzed in the yeast strain bybioluminescence imaging. (AU)

Scientific publications

(References retrieved automatically from Web of Science and SciELO through information on FAPESP grants and their corresponding numbers as mentioned in the publications by the authors)

FREIRE, FERNANDA; FERRARESI, CLEBER; JORGE, ANTONIO OLAVO C.; HAMBLIN, MICHAEL R. Photodynamic therapy of oral Candida infection in a mouse model. JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY B-BIOLOGY, v. 159, p. 161-168, JUN 2016. Web of Science Citations: 26.