Poster (Painel)
823-3Phenotypic switching has effect on virulence factors in clinical isolates of Candida tropicalis
Autores:Alane Tatiana Pereira Moralez (UEL - Universidade Estadual de Londrina) ; Luiz Cláudio dos Santos Ferreira (UEL - Universidade Estadual de Londrina) ; Emanuele Julio Galvão de França (UEL - Universidade Estadual de Londrina) ; Marcia Cristina Furlaneto (UEL - Universidade Estadual de Londrina)


Candida tropicalis is an increasingly important human pathogen. In Latin America, C.tropicalis accounts for the majority of non-albicans Candida species associated with candidemia episodes. However, little is known about its potential to cause disease. Phenotypic switching has been considered as a putative virulence factor in Candida spp. and also seems to promote the differential expression of other virulence factors. The aims of this study were to obtain and characterize stable morphological colony variants (morphotypes) arising by phenotypic switching event from 5 clinical isolates of C. tropicalis and to perform a comparative analysis between morphotypes variants and their parental counterparts for the expression of the following virulence attributes: ability to produce biofilm, production of filamentous forms; potential of agar invasion. Stable morphotypes were identified and characterized as smooth, flower and rough (isolate 49.07), smooth, crater and irregular center (isolate 335.07) fuzzy and mycelial (isolate 46.10); smooth, crepe and flocked (isolate 100.10) and semi-smooth and diffuse (isolate 236.10). Biofilm production data revealed significant differences between morphotypes smooth and flower and smooth and rough (isolate 49.07) and between the smooth and crepe morphotypes (isolate 100.10). Morphotypes variants showed higher percentages of filamentous forms in relation to their respective parental morphotypes. The fracture technique of colony and ultrastructural evaluation revealed that morphotype colonies more structured were more invasive and morphotype variants had a higher density of filamentous cells at the time of invasion compared to their parental morphotypes. The data suggest that phenotypic switching in C. tropicalis may promote differential expression of some virulence factors in this species.

Palavras-chave:  Candida tropicalis, Phenotypic switching, Virulence factors