Candida-streptococcal mucosal biofilms display distinct structural and virulence characteristics depending on growth conditions and hyphal morphotypes

Autor(es)

Bertolini, M. M. ^[1] ; Xu, H. ^[1] ; Sobue, T. ^[1] ; Nobile, C. J. ^[2] ; Del Bel Cury, A. A. ^[3] ; Dongari-Bagtzoglou, A. ^[1]

Afiliação do(s) autor(es)

^[1] Univ Connecticut, Sch Dent Med, Div Periodontol, Farmington, CT 06030 - USA

^[2] Univ Calif, Sch Nat Sci, Merced, CA - USA

^[3] Univ Estadual Campinas, Piracicaba Dent Sch, Div Prosthodont & Periodontol, Piracicaba, SP - Brazil

• Tipo de documento: Artigo Científico
• Fonte: Molecular Oral Microbiology; v. 30, n. 4, p. 307-322, AUG 2015.
• Citações Web of Science: 18

Resumo

Candida albicans and streptococci of the mitis group form communities in multiple oral sites, where moisture and nutrient availability can change spatially or temporally. This study evaluated structural and virulence characteristics of Candida-streptococcal biofilms formed on moist or semidry mucosal surfaces, and tested the effects of nutrient availability and hyphal morphotype on dual-species biofilms. Three-dimensional models of the oral mucosa formed by immortalized keratinocytes on a fibroblast-embedded collagenous matrix were used. Infections were carried out using Streptococcus oralis strain 34, in combination with a C.albicans wild-type strain, or pseudohyphal-forming mutant strains. Increased moisture promoted a homogeneous surface biofilm by C.albicans. Dual biofilms had a stratified structure, with streptococci growing in close contact with the mucosa and fungi growing on the bacterial surface. Under semidry conditions, Candida formed localized foci of dense growth, which promoted focal growth of streptococci in mixed biofilms. Candida biofilm biovolume was greater under moist conditions, albeit with minimal tissue invasion, compared with semidry conditions. Supplementing the infection medium with nutrients under semidry conditions intensified growth, biofilm biovolume and tissue invasion/damage, without changing biofilm structure. Under these conditions, the pseudohyphal mutants and S.oralis formed defective superficial biofilms, with most bacteria in contact with the epithelial surface, below a pseudohyphal mass, resembling biofilms growing in a moist environment. The presence of S.oralis promoted fungal invasion and tissue damage under all conditions. We conclude that moisture, nutrient availability, hyphal morphotype and the presence of commensal bacteria influence the architecture and virulence characteristics of mucosal fungal biofilms. (AU)

• Processo FAPESP: 12/21011-8 - Condições de crescimento influenciam as características estruturais e de virulência de biofilmes de Candida e Streptococcus formados sobre modelos in vitro de mucosa oral humana
• Beneficiário: Martinna de Mendonça e Bertolini
• Modalidade de apoio: Bolsas no Brasil - Doutorado
• Processo FAPESP: 13/00274-3 - Influência do fluconazol na resposta imune a infecção por Candida albicans em modelo in vitro de epitélio oral
• Beneficiário: Altair Antoninha Del Bel Cury
• Modalidade de apoio: Auxílio à Pesquisa - Regular