XXI ALAM
Resumo:353-1


Poster (Painel)
353-1PDR1 GENE EXPRESSION QUANTIFICATION IN Cryptococcus neoformans BIOFILM.
Autores:Fernanda Campos de Medeiros (FCFAR - Faculdade de Ciências Farmacêuticas, UNESP Araraquara) ; Tatiane Benaducci (FCFAR - Faculdade de Ciências Farmacêuticas, UNESP Araraquara) ; Suelen Andréia Rossi (FCFAR - Faculdade de Ciências Farmacêuticas, UNESP Araraquara) ; Caroline Barcelos Costa Orlandi (FCFAR - Faculdade de Ciências Farmacêuticas, UNESP Araraquara) ; Ana Marisa Fusco Almeida (FCFAR - Faculdade de Ciências Farmacêuticas, UNESP Araraquara) ; Maria José Soares Mendes Giannini (FCFAR - Faculdade de Ciências Farmacêuticas, UNESP Araraquara)

Resumo

The Cryptococcosis is a disease with high mortality, especially in HIV positive patients, caused by the encapsulated yeast Cryptococcus neoformans and Cryptococcus gattii. Biofilm formation in Cryptococcus sp. influences the fungal infection and is associated with the persistent infection, since it increases the resistance to the host immune mechanisms and antimicrobial therapy. The efflux pumps are important factors in determining the resistance of biofilms to antifungal azoles. The PDR1 gene was described in Candida albicans as regulator of CDR1 and CDR2 genes, already related to the efflux pump. The deletion of the gene in question results in the reduction or loss of resistance to antifungals. Thus, this study aimed to quantify PDR1 gene expression in biofilm in two strains of Cryptococcus neoformans, one of them sensitive (ATCC 90012) and other resistant to fluconazole (30). The biofilm of both strains was formed, and cell viability was confirmed by the Cell Viability Assay (XTT). The RNA was obtained from the biofilm for to be quantified by Real Time PCR, in order to quantify PDR1 gene expression. It was also performed using scanning microscopy to verify the formation and biofilm thickness. The strain resistant to fluconazole (30) had a higher PDR1 gene expression in relation to the ATCC sensitive. Furthermore, the observation by scanning microscopy revealed that the biofilm formed by the resistant strain was thicker and denser than the biofilm formed by the sensitive strain. The results suggest that, also in Cryptococcus neoformans, PDR1 gene can be linked to the biofilm formation. The molecular bases of biofilm formation and resistance to antifungals have been little studied in Cryptococcus sp, however the understanding of the molecular mechanism for the biofilm formation of C. neoformans requires further investigation.


Palavras-chave:  Biofilm, Cryptococcus neoformans, PDR1, Resistance