Author(s): Frazão, Stefânia de Oliveira ; Sousa, Herdson Renney de ; Silva, Lenise Gonçalves da ; Folha, Jéssica dos Santos ; Gorgonha, Kaio César de Melo ; Oliveira Júnior, Getúlio Pereira de ; Felipe, Maria Sueli Soares ; Pereira, Ildinete Silva ; Casadevall, Arturo ; Nicola, André Moraes ; Andrade, Patrícia Albuquerque de
Date: 2021
Origin: Oasisbr
Subject(s): Cryptococcus neoformans; Leveduras; Enzimas de fungos; Macrófagos; Exocitose não-lítica
Nonlytic exocytosis is a process in which previously ingested microbes are expelled from host phagocytes with the concomitant survival of both cell types. This process has been observed in the interaction of Cryptococcus spp. and other fungal cells with phagocytes as distant as mammalian, bird, and fish macrophages and ameboid predators. Despite a great amount of research dedicated to unraveling this process, there are still many questions about its regulation and its final benefits for host or fungal cells. During a study to characterize the virulence attributes of Brazilian clinical isolates of C. neoformans, we observed great variability in their rates of nonlytic exocytosis and noted a correlation between this process and fungal melanin production/laccase activity. Flow cytometry experiments using melanized cells, nonmelanized cells, and lac1Δ mutants revealed that laccase has a role in the process of nonlytic exocytosis that seems to be independent of melanin production. These results identify a role for laccase in virulence, independent of its role in pigment production, that represents a new variable in the regulation of nonlytic exocytosis.
