Soňa Kucharíková1, Bram Neirinck2, Nidhi Sharma1, Jef Vleugels2, Katrien Lagrou3, Patrick Van Dijck4. 1. Department of Molecular Microbiology, VIB, KU Leuven, Leuven, Belgium Laboratory of Molecular Cell Biology, Institute of Botany and Microbiology, KU Leuven, Kasteelpark Arenberg 31, B-3001 Heverlee-Leuven, Belgium. 2. Department of Materials Engineering, KU Leuven, Kasteelpark Arenberg 44, B-3001 Heverlee-Leuven, Belgium. 3. Department of Microbiology and Immunology, KU Leuven, Leuven, Belgium. 4. Department of Molecular Microbiology, VIB, KU Leuven, Leuven, Belgium Laboratory of Molecular Cell Biology, Institute of Botany and Microbiology, KU Leuven, Kasteelpark Arenberg 31, B-3001 Heverlee-Leuven, Belgium patrick.vandijck@mmbio.vib-kuleuven.be.
Abstract
OBJECTIVES: Biofilm studies have been mostly dedicated to the major human fungal pathogen Candida albicans, whereas much less is known about this virulence factor in Candida glabrata, certainly under in vivo conditions. This study provides a deeper understanding of the biofilm development of C. glabrata, its architecture and susceptibility profile to fluconazole and echinocandins. METHODS: In vitro and in vivo C. glabrata biofilms were developed inside serum-coated triple-lumen catheters placed in 24-well polystyrene plates or implanted subcutaneously in the back of a rat, respectively. Scanning electron microscopy and confocal scanning laser microscopy were used to visualize the biofilm architecture. Quantitative real-time PCR was used to demonstrate the expression profile of EPA1, EPA3, EPA6 and AWP1-AWP7 during in vivo biofilm formation. RESULTS: Mature biofilms were observed within the first 48 h and the amount of biofilm reached its maximum by 6 days. Architecturally, mature C. glabrata biofilms consisted of a thick network of yeast cells embedded in an extracellular matrix. Moreover, in vivo biofilms were susceptible to echinocandin drugs, whereas fluconazole remained ineffective. Gene expression profiling revealed that EPA3, EPA6, AWP2, AWP3 and AWP5 were up-regulated in in vivo biofilms compared with in vitro biofilms. CONCLUSIONS: C. glabrata is a unique microorganism, which, despite the lack of transition to the hyphal form, formed thick biofilms inside foreign bodies in vivo. To our knowledge, this is the first study that has described in vivo C. glabrata biofilm development and its architectural changes in detail and provides an insight into the susceptibility profile, as well as the gene expression machinery, of biofilm-associated infections.
OBJECTIVES: Biofilm studies have been mostly dedicated to the major human fungal pathogen Candida albicans, whereas much less is known about this virulence factor in Candida glabrata, certainly under in vivo conditions. This study provides a deeper understanding of the biofilm development of C. glabrata, its architecture and susceptibility profile to fluconazole and echinocandins. METHODS: In vitro and in vivo C. glabrata biofilms were developed inside serum-coated triple-lumen catheters placed in 24-well polystyrene plates or implanted subcutaneously in the back of a rat, respectively. Scanning electron microscopy and confocal scanning laser microscopy were used to visualize the biofilm architecture. Quantitative real-time PCR was used to demonstrate the expression profile of EPA1, EPA3, EPA6 and AWP1-AWP7 during in vivo biofilm formation. RESULTS: Mature biofilms were observed within the first 48 h and the amount of biofilm reached its maximum by 6 days. Architecturally, mature C. glabrata biofilms consisted of a thick network of yeast cells embedded in an extracellular matrix. Moreover, in vivo biofilms were susceptible to echinocandin drugs, whereas fluconazole remained ineffective. Gene expression profiling revealed that EPA3, EPA6, AWP2, AWP3 and AWP5 were up-regulated in in vivo biofilms compared with in vitro biofilms. CONCLUSIONS:C. glabrata is a unique microorganism, which, despite the lack of transition to the hyphal form, formed thick biofilms inside foreign bodies in vivo. To our knowledge, this is the first study that has described in vivo C. glabrata biofilm development and its architectural changes in detail and provides an insight into the susceptibility profile, as well as the gene expression machinery, of biofilm-associated infections.
Authors: F Jerry Reen; John P Phelan; Lorna Gallagher; David F Woods; Rachel M Shanahan; Rafael Cano; Eoin Ó Muimhneacháin; Gerard P McGlacken; Fergal O'Gara Journal: Antimicrob Agents Chemother Date: 2016-09-23 Impact factor: 5.191
Authors: Caroline B Costa-Orlandi; Janaina C O Sardi; Nayla S Pitangui; Haroldo C de Oliveira; Liliana Scorzoni; Mariana C Galeane; Kaila P Medina-Alarcón; Wanessa C M A Melo; Mônica Y Marcelino; Jaqueline D Braz; Ana Marisa Fusco-Almeida; Maria José S Mendes-Giannini Journal: J Fungi (Basel) Date: 2017-05-10