title: Low-level laser therapy to the mouse femur enhances the fungicidal response of neutrophils against Paracoccidioides brasiliensis.
abstract: Neutrophils (PMN) play a central role in host defense against the neglected fungal infection paracoccidioidomycosis (PCM), which is caused by the dimorphic fungus Paracoccidioides brasiliensis (Pb). PCM is of major importance, especially in Latin America, and its treatment relies on the use of antifungal drugs. However, the course of treatment is lengthy, leading to side effects and even development of fungal resistance. The goal of the study was to use low-level laser therapy (LLLT) to stimulate PMN to fight Pb in vivo. Swiss mice with subcutaneous air pouches were inoculated with a virulent strain of Pb or fungal cell wall components (Zymosan), and then received LLLT (780 nm; 50 mW; 12.5 J/cm2; 30 seconds per point, giving a total energy of 0.5 J per point) on alternate days at two points on each hind leg. The aim was to reach the bone marrow in the femur with light. Non-irradiated animals were used as controls. The number and viability of the PMN that migrated to the inoculation site was assessed, as well as their ability to synthesize proteins, produce reactive oxygen species (ROS) and their fungicidal activity. The highly pure PMN populations obtained after 10 days of infection were also subsequently cultured in the presence of Pb for trials of protein production, evaluation of mitochondrial activity, ROS production and quantification of viable fungi growth. PMN from mice that received LLLT were more active metabolically, had higher fungicidal activity against Pb in vivo and also in vitro. The kinetics of neutrophil protein production also correlated with a more activated state. LLLT may be a safe and non-invasive approach to deal with PCM infection.
authors: Department of Microbiology and Immunology, Institute of Biomedical Sciences, Federal University of Alfenas (UNIFAL-MG), Alfenas, Minas Gerais, Brazil.
authors: Eva
authors: E
authors: Burger
authors: Department of Microbiology and Immunology, Institute of Biomedical Sciences, Federal University of Alfenas (UNIFAL-MG), Alfenas, Minas Gerais, Brazil.
authors: Ana Carolina S C
authors: AC
authors: Mendes
authors: Department of Microbiology and Immunology, Institute of Biomedical Sciences, Federal University of Alfenas (UNIFAL-MG), Alfenas, Minas Gerais, Brazil.
authors: Giulia M A C
authors: GM
authors: Bani
authors: Department of Biochemistry, Institute of Biomedical Sciences, Federal University of Alfenas (UNIFAL-MG), Alfenas, Minas Gerais, Brazil.
authors: Maísa R P L
authors: MR
authors: Brigagão
authors: Department of Biochemistry, Institute of Biomedical Sciences, Federal University of Alfenas (UNIFAL-MG), Alfenas, Minas Gerais, Brazil.
authors: Gérsika B
authors: GB
authors: Santos
authors: Department of Microbiology and Immunology, Institute of Biomedical Sciences, Federal University of Alfenas (UNIFAL-MG), Alfenas, Minas Gerais, Brazil.
authors: Luiz Cosme C
authors: LC
authors: Malaquias
authors: Department of Microbiology and Immunology, Institute of Biomedical Sciences, Federal University of Alfenas (UNIFAL-MG), Alfenas, Minas Gerais, Brazil.
authors: Jorge Kleber
authors: JK
authors: Chavasco
authors: Department of Structural and Functional Biology, Institute of Biology, State University of Campinas (UNICAMP), Campinas, São Paulo, Brazil.
authors: Liana M
authors: LM
authors: Verinaud
authors: Department of Microbiology, Immunology and Parasitology, Federal University of São Paulo (UNIFESP), São Paulo, São Paulo, Brazil.
authors: Zoilo P
authors: ZP
authors: de Camargo
authors: Wellman Center for Photomedicine, Massachusetts General Hospital, Boston, Massachusetts, United States of America; Department of Dermatology, Harvard Medical School, Boston, Massachusetts, United States of America; Harvard-MIT Division of Health Sciences and Technology, Cambridge, Massachusetts, United States of America.
authors: Michael R
authors: MR
authors: Hamblin
authors: Wellman Center for Photomedicine, Massachusetts General Hospital, Boston, Massachusetts, United States of America; Department of Dermatology, Harvard Medical School, Boston, Massachusetts, United States of America; Department of Pathology and Parasitology, Institute of Biomedical Sciences, Federal University of Alfenas (UNIFAL-MG), Alfenas, Minas Gerais, Brazil.
authors: Felipe F
authors: FF
authors: Sperandio
mesh_terms: D000818:Animals; D001853:Bone Marrow / Q000276:immunology* / Q000528:radiation effects; D005260:Female; D005269:Femur / Q000382:microbiology; D028022:Low-Level Light Therapy / Q000379:methods*; D051379:Mice; D008928:Mitochondria / Q000378:metabolism; D009504:Neutrophils / Q000276:immunology; D010228:Paracoccidioides / Q000276:immunology / Q000528:radiation effects; D010229:Paracoccidioidomycosis / Q000276:immunology* / Q000382:microbiology / Q000628:therapy*; D017382:Reactive Oxygen Species / Q000378:metabolism
chemical_list: D017382:Reactive Oxygen Species