EVALUATION OF BIOFILM FORMATION of Paracoccidioides brasiliensis IN A THREE-DIMENSIONAL SPHEROID MODEL IN REGARD TO THE ROLE OF ADHESINS 14-3-3 AND METHODS OF CONTROL.

• Grant number: 24/03014-7
• Support Opportunities: Scholarships in Brazil - Master
• Effective date (Start): September 01, 2024
• Effective date (End): January 31, 2026
• Field of knowledge: Health Sciences - Pharmacy
• Principal Investigator: Maria José Soares Mendes Giannini
• Grantee: Henrique Gomes Martins
• Host Institution: Faculdade de Ciências Farmacêuticas (FCFAR). Universidade Estadual Paulista (UNESP). Campus de Araraquara. Araraquara , SP, Brazil

Abstract

Paracoccidioidomycosis is a systemic mycosis caused by the thermodimorphic pathogenic fungus ofthe genus Paracoccidioides. It is considered a neglected tropical disease of great importance in Latin American countries, mainly affecting rural workers. Several factors determining virulence, such as dimorphism, changes in cell wall composition, adhesins, and biofilm formation, have been reported and may play a relevant role in its pathogenesis. Studies suggest that silencing the 14-3-3 protein (adhesin) altered the ability to form biofilm and its metabolism. When comparing the silenced strain for the 14-3-3 adhesin with the wild strain, an increase in the expression of the enolase, GAPDH, and 14-3-3 genes in biofilms was found with the wild strain, indicating that gene silencing can influence the expression of other genes, as well as being involved in biofilm formation. Polysaccharides predominate in this fungus's extracellular matrix, and the main component, such as 1,3 ²-glucan, may play a crucial role in biofilm formation and its genesis. The relevance of biofilms to human infections needs to be better studied in the context of in vitro, ex-vivo, and in vivo models, focusing on factors related to their formation, virulence and antibiofilm drugs. Three-dimensional (3D) cell culture models are more faithful to what is observed in in vitro models and can range from spheroids in monoculture or co-culture of various cell types to those that demonstrate the unctionality of organs in vivo, representedby in vitro stratified tissues. In this context, the importance of evaluating the role of 14-3-3 adhesin and 1,3 ²-glucan in P. brasiliensis biofilm formation is essential, comparing strains with mutation with the wild-type strain of Pb18 in skin keratinocytes human (HaCat) and human dermal fibroblast (HDFa) in a three-dimensional (3D) model with an emphasis on cutaneous paracoccidioidomycosis and application of control strategies.