Action of DNase produced by Paracoccidioides Brasiliensis on nets (neutrophil extracellular traps) released by human neutrophils in response to the fungus

• Grant number: 17/26230-3
• Support Opportunities: Scholarships in Brazil - Master
• Start date: April 01, 2018
• End date: February 29, 2020
• Field of knowledge: Biological Sciences - Immunology - Applied Immunology
• Agreement: Coordination of Improvement of Higher Education Personnel (CAPES)
• Principal Investigator: Luciane Alarcão Dias-Melicio
• Grantee: Yohan Ricci Zonta
• Host Institution: Faculdade de Medicina (FMB). Universidade Estadual Paulista (UNESP). Campus de Botucatu. Botucatu , SP, Brazil

Abstract

The paracoccidioidiomycosis (PCM) is a systemic disease considered endemic in Latin America. Its etiological agentes, fungi of the paracoccidioides complex, can be classified as dimorphic fungi. Its infectant phase is conidios that have restricted geographical habitats. This fungal infection occurs due the inhalation of conidios, which leads to a strong immunological response in the lungs. Granulomatous lesion are common of infection, and in a dependancy of the clinical forms, the fungus can disseminate for other parts of the human body. Neutrophils, phagocytic cells of innate immunity, are the main responsible for defensive response called NETosis, that´s result in Neutrophil Extracellular Traps (NETs) production. The NETs are capable of trapping and destroying the fungus. However, studies already showed the capability of some fungi to produce certain proteins, such as DNAse or DNAse like protein, as a escape mechanisms from NETs. In this way, the general objective of this work will be to identify the production, release and different patterns of NETs in response to the different strains of the fungus in the human neutrophil cultures challenged with Pb18 (virulent) and Pb265 (avirulent) strains, correlating with ability of these strains to produce DNAse in these cultures. To do so, the following steps will be taken: (1) Isolation of neutrophils from peripheral blood of 15 healthy individuals and challenge with different strains of fungi. (3) Analysis of production of different NET patterns during challenge using Confocal Microscopy, Electronic Scanning Microscopy and High Content analysis. (4) Quantification of NETs by fluorimetric kit Quant-iT PicoGreen. (5) Finally, quantification of the fungal DNAse gene encoded, by mRNA expression performed by RT-PCR. (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)

ZONTA, YOHAN RICCI; DEZEN, ANA LAURA ORTEGA; DELLA COLETTA, AMANDA MANOEL; YU, KAIO SHU TSYR; CARVALHO, LARISSA; SANTOS, LEANDRO ALVES DOS; DEPRA, IGOR DE CARVALHO; KRATOFIL, RACHEL M.; WILLSON, MICHELLE ELIZABETH; ZBYTNUIK, LORI; et al. Paracoccidioides brasiliensis Releases a DNase-Like Protein That Degrades NETs and Allows for Fungal Escape. FRONTIERS IN CELLULAR AND INFECTION MICROBIOLOGY, v. 10, FEB 10 2021. (18/09706-7, 17/26230-3)

Academic Publications

(References retrieved automatically from State of São Paulo Research Institutions)

ZONTA, Yohan Ricci. DNAse action produced by Paracoccidioides brasiliensis on NETs (Neutrophil Extracellular Traps) released by human neutrophils in response to the fungus. 2020. Master's Dissertation - Universidade Estadual Paulista (Unesp). Faculdade de Medicina. Botucatu Botucatu.