1
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Roosen L, Maes D, Musetta L, Himmelreich U. Preclinical Models for Cryptococcosis of the CNS and Their Characterization Using In Vivo Imaging Techniques. J Fungi (Basel) 2024; 10:146. [PMID: 38392818 PMCID: PMC10890286 DOI: 10.3390/jof10020146] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2023] [Revised: 01/24/2024] [Accepted: 01/30/2024] [Indexed: 02/24/2024] Open
Abstract
Infections caused by Cryptococcus neoformans and Cryptococcus gattii remain a challenge to our healthcare systems as they are still difficult to treat. In order to improve treatment success, in particular for infections that have disseminated to the central nervous system, a better understanding of the disease is needed, addressing questions like how it evolves from a pulmonary to a brain disease and how novel treatment approaches can be developed and validated. This requires not only clinical research and research on the microorganisms in a laboratory environment but also preclinical models in order to study cryptococci in the host. We provide an overview of available preclinical models, with particular emphasis on models of cryptococcosis in rodents. In order to further improve the characterization of rodent models, in particular the dynamic aspects of disease manifestation, development, and ultimate treatment, preclinical in vivo imaging methods are increasingly used, mainly in research for oncological, neurological, and cardiac diseases. In vivo imaging applications for fungal infections are rather sparse. A second aspect of this review is how research on models of cryptococcosis can benefit from in vivo imaging methods that not only provide information on morphology and tissue structure but also on function, metabolism, and cellular properties in a non-invasive way.
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Affiliation(s)
- Lara Roosen
- Biomedical MRI, Department of Imaging and Pathology, KU Leuven, 3000 Leuven, Belgium
| | - Dries Maes
- Biomedical MRI, Department of Imaging and Pathology, KU Leuven, 3000 Leuven, Belgium
| | - Luigi Musetta
- Biomedical MRI, Department of Imaging and Pathology, KU Leuven, 3000 Leuven, Belgium
| | - Uwe Himmelreich
- Biomedical MRI, Department of Imaging and Pathology, KU Leuven, 3000 Leuven, Belgium
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2
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Pinto RM, Yazdani S, Seabra CL, De Jonge M, Izci M, Cruz R, Casal S, Soenen SJ, Reis S, Nunes C, Van Dijck P. Non disseminative nano-strategy against in vivo Staphylococcus aureus biofilms. NPJ Biofilms Microbiomes 2023; 9:39. [PMID: 37328504 DOI: 10.1038/s41522-023-00405-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2023] [Accepted: 06/05/2023] [Indexed: 06/18/2023] Open
Abstract
Staphylococcus aureus is considered a high priority pathogen by the World Health Organization due to its high prevalence and the potential to form biofilms. Currently, the available treatments for S. aureus biofilm-associated infections do not target the extracellular polymeric substances (EPS) matrix. This matrix is a physical barrier to bactericidal agents, contributing to the increase of antimicrobial tolerance. The present work proposes the development of lipid nanoparticles encapsulating caspofungin (CAS) as a matrix-disruptive nanosystem. The nanoparticles were functionalized with D-amino acids to target the matrix. In a multi-target nano-strategy against S. aureus biofilms, CAS-loaded nanoparticles were combined with a moxifloxacin-loaded nanosystem, as an adjuvant to promote the EPS matrix disruption. In vitro and in vivo studies showed biofilm reduction after combining the two nanosystems. Besides, the combinatory therapy showed no signs of bacterial dissemination into vital organs of mice, while dissemination was observed for the treatment with the free compounds. Additionally, the in vivo biodistribution of the two nanosystems revealed their potential to reach and accumulate in the biofilm region, after intraperitoneal administration. Thus, this nano-strategy based on the encapsulation of matrix-disruptive and antibacterial agents is a promising approach to fight S. aureus biofilms.
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Affiliation(s)
- Rita M Pinto
- LAQV, REQUIMTE, Departamento de Ciências Químicas, Faculdade de Farmácia, Universidade do Porto, 4050-313, Porto, Portugal
- Laboratory of Molecular Cell Biology, Institute of Botany and Microbiology, KU Leuven, 3001, Leuven, Belgium
| | - Saleh Yazdani
- Laboratory of Molecular Cell Biology, Institute of Botany and Microbiology, KU Leuven, 3001, Leuven, Belgium
| | - Catarina Leal Seabra
- LAQV, REQUIMTE, Departamento de Ciências Químicas, Faculdade de Farmácia, Universidade do Porto, 4050-313, Porto, Portugal
| | - Martine De Jonge
- Laboratory of Molecular Cell Biology, Institute of Botany and Microbiology, KU Leuven, 3001, Leuven, Belgium
| | - Mukaddes Izci
- NanoHealth and Optical Imaging Group, Translational Cell and Tissue Research Unit, Department of Imaging and Pathology, KU Leuven, Leuven, Belgium
| | - Rebeca Cruz
- LAQV, REQUIMTE, Departamento de Ciências Químicas, Faculdade de Farmácia, Universidade do Porto, 4050-313, Porto, Portugal
| | - Susana Casal
- LAQV, REQUIMTE, Departamento de Ciências Químicas, Faculdade de Farmácia, Universidade do Porto, 4050-313, Porto, Portugal
| | - Stefaan J Soenen
- NanoHealth and Optical Imaging Group, Translational Cell and Tissue Research Unit, Department of Imaging and Pathology, KU Leuven, Leuven, Belgium
| | - Salette Reis
- LAQV, REQUIMTE, Departamento de Ciências Químicas, Faculdade de Farmácia, Universidade do Porto, 4050-313, Porto, Portugal
| | - Cláudia Nunes
- LAQV, REQUIMTE, Departamento de Ciências Químicas, Faculdade de Farmácia, Universidade do Porto, 4050-313, Porto, Portugal.
| | - Patrick Van Dijck
- Laboratory of Molecular Cell Biology, Institute of Botany and Microbiology, KU Leuven, 3001, Leuven, Belgium.
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3
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Brown AJP. Fungal resilience and host-pathogen interactions: Future perspectives and opportunities. Parasite Immunol 2023; 45:e12946. [PMID: 35962618 PMCID: PMC10078341 DOI: 10.1111/pim.12946] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2022] [Revised: 08/08/2022] [Accepted: 08/10/2022] [Indexed: 01/31/2023]
Abstract
We are constantly exposed to the threat of fungal infection. The outcome-clearance, commensalism or infection-depends largely on the ability of our innate immune defences to clear infecting fungal cells versus the success of the fungus in mounting compensatory adaptive responses. As each seeks to gain advantage during these skirmishes, the interactions between host and fungal pathogen are complex and dynamic. Nevertheless, simply compromising the physiological robustness of fungal pathogens reduces their ability to evade antifungal immunity, their virulence, and their tolerance against antifungal therapy. In this article I argue that this physiological robustness is based on a 'Resilience Network' which mechanistically links and controls fungal growth, metabolism, stress resistance and drug tolerance. The elasticity of this network probably underlies the phenotypic variability of fungal isolates and the heterogeneity of individual cells within clonal populations. Consequently, I suggest that the definition of the fungal Resilience Network represents an important goal for the future which offers the clear potential to reveal drug targets that compromise drug tolerance and synergise with current antifungal therapies.
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Affiliation(s)
- Alistair J P Brown
- Medical Research Council Centre for Medical Mycology at the University of Exeter, Exeter, UK
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4
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Resendiz-Sharpe A, Vanhoffelen E, Velde GV. Bioluminescence Imaging, a Powerful Tool to Assess Fungal Burden in Live Mouse Models of Infection. Methods Mol Biol 2023; 2667:197-210. [PMID: 37145286 DOI: 10.1007/978-1-0716-3199-7_15] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/06/2023]
Abstract
Aspergillus fumigatus and Cryptococcus neoformans species infections are two of the most common life-threatening fungal infections in the immunocompromised population. Acute invasive pulmonary aspergillosis (IPA) and meningeal cryptococcosis are the most severe forms affecting patients with elevated associated mortality rates despite current treatments. As many unanswered questions remain concerning these fungal infections, additional research is greatly needed not only in clinical scenarios but also under controlled preclinical experimental settings to increase our understanding concerning their virulence, host-pathogen interactions, infection development, and treatments. Preclinical animal models are powerful tools to gain more insight into some of these needs. However, assessment of disease severity and fungal burden in mouse models of infection are often limited to less sensitive, single-time, invasive, and variability-prone techniques such as colony-forming unit counting. These issues can be overcome by in vivo bioluminescence imaging (BLI). BLI is a noninvasive tool that provides longitudinal dynamic visual and quantitative information on the fungal burden from the onset of infection and potential dissemination to different organs throughout the development of disease in individual animals. Hereby, we describe an entire experimental pipeline from mouse infection to BLI acquisition and quantification, readily available to researchers to provide a noninvasive, longitudinal readout of fungal burden and dissemination throughout the course of infection development, which can be applied for preclinical studies into pathophysiology and treatment of IPA and cryptococcosis in vivo.
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Affiliation(s)
| | - Eliane Vanhoffelen
- KU Leuven, Department of Imaging and Pathology, Biomedical MRI / MoSAIC, Leuven, Belgium
| | - Greetje Vande Velde
- KU Leuven, Department of Imaging and Pathology, Biomedical MRI / MoSAIC, Leuven, Belgium.
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5
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Schrevens S, Torelli R, Sanguinetti M, Sanglard D. Using Bioluminescence to Image Candida glabrata Urinary Tract Infections in Mice. Methods Mol Biol 2023; 2658:239-247. [PMID: 37024707 DOI: 10.1007/978-1-0716-3155-3_17] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/08/2023]
Abstract
The human fungal pathogen Candida glabrata is less virulent compared to the most isolated Candida species including Candida albicans. Its reduced metabolic flexibility, haploidy, and auxotrophies contribute to a "stealth and evasion" infection strategy, resulting in minimal tissue damage in the host. C. glabrata seems to be optimally adapted to infection of the urinary tract (UTI), especially in catheterized patients. UTIs are not well studied and often difficult to treat, given that not all antifungals penetrate in the bladder and that treatments through the catheter are not always possible since maintained catheterization increases the infection risk.In the recent effort to reduce the amount of animals used during scientific experiments, bioluminescence imaging is a useful tool. In this protocol, C. glabrata urinary tract infections were imaged in mice, thus facilitating the testing of possible new antifungals and novel treatment strategies.
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Affiliation(s)
- Sanne Schrevens
- Institute of Microbiology, University of Lausanne and University Hospital, Lausanne, Switzerland
| | - Riccardo Torelli
- Dipartimento di Scienze di Laboratorio e Infettivologiche, Fondazione Policlinico Universitario A. Gemelli IRCCS, Rome, Italy
| | - Maurizio Sanguinetti
- Dipartimento di Scienze di Laboratorio e Infettivologiche, Fondazione Policlinico Universitario A. Gemelli IRCCS, Rome, Italy
- Dipartimento di Scienze Biotecnologiche di Base, Cliniche Intensivologiche e Perioperatorie, Università Cattolica del Sacro Cuore, Rome, Italy
| | - Dominque Sanglard
- Institute of Microbiology, University of Lausanne and University Hospital, Lausanne, Switzerland.
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6
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Antibiofilm Combinatory Strategy: Moxifloxacin-Loaded Nanosystems and Encapsulated N-Acetyl-L-Cysteine. Pharmaceutics 2022; 14:pharmaceutics14112294. [PMID: 36365113 PMCID: PMC9699636 DOI: 10.3390/pharmaceutics14112294] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2022] [Revised: 10/20/2022] [Accepted: 10/22/2022] [Indexed: 11/29/2022] Open
Abstract
Bacterial biofilms of Staphylococcus aureus, formed on implants, have a massive impact on the increasing number of antimicrobial resistance cases. The current treatment for biofilm-associated infections is based on the administration of antibiotics, failing to target the biofilm matrix. This work is focused on the development of multiple lipid nanoparticles (MLNs) encapsulating the antibiotic moxifloxacin (MOX). The nanoparticles were functionalized with d-amino acids to target the biofilm matrix. The produced formulations exhibited a mean hydrodynamic diameter below 300 nm, a low polydispersity index, and high encapsulation efficiency. The nanoparticles exhibited low cytotoxicity towards fibroblasts and low hemolytic activity. To target bacterial cells and the biofilm matrix, MOX-loaded MLNs were combined with a nanosystem encapsulating a matrix-disruptive agent: N-acetyl-L-cysteine (NAC). The nanosystems alone showed a significant reduction of both S. aureus biofilm viability and biomass, using the microtiter plate biofilm model. Further, biofilms grown inside polyurethane catheters were used to assess the effect of combining MOX-loaded and NAC-loaded nanosystems on biofilm viability. An increased antibiofilm efficacy was observed when combining the functionalized MOX-loaded MLNs and NAC-loaded nanosystems. Thus, nanosystems as carriers of bactericidal and matrix-disruptive agents are a promising combinatory strategy towards the eradication of S. aureus biofilms.
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7
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Streptomyces: Derived Active Extract Inhibits Candida albicans Biofilm Formation. Curr Microbiol 2022; 79:332. [PMID: 36155861 DOI: 10.1007/s00284-022-03013-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2022] [Accepted: 08/27/2022] [Indexed: 11/03/2022]
Abstract
Candida albicans is an opportunistic pathogen that causes biofilm-associated infections. C. albicans biofilms are known to display reduced susceptibility to antimicrobials and high rates of acquired antibiotic resistance, and biofilm forming in C. albicans further hampers treatment options and highlights the need for new antibiofilm strategies. Identifying active components from desert actinomycetes strains to inhibit the formation of C. albicans biofilms represents an effective treatment strategy. In this study, actinomycetes that can inhibit C. albicans biofilm formation were isolated from the Taklimakan Desert, and the underlying mechanisms were explored. After screening the anti-C.albicans biofilm activities of culture supernatants from 170 Actinomycete strains, six strains showed significant inhibition of C. albicans biofilm formation. Microscopic examination showed a reduction in biofilm formation of C. albicans treated with supernatants from actinomycetes. Scanning electron microscopy showed that the morphological changes in biofilm cells were caused by cell membrane rupture and cell material leakage. Then, C.albicans biofilms were destroyed by changing the content of extracellular polysaccharides or degrading extracellular DNA. Finally, a preliminary study on active substances extracted from a new species (TRM43335) showed that the substances that inhibited the formation of biofilms might be peptides. This study provides preliminary evidence that desert actinomyces strains have inhibitory effects on the biofilm development of C. albicans.
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8
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Bioluminescence imaging in Paracoccidioides spp.: A tool to monitor the infectious processes. Microbes Infect 2022; 24:104975. [DOI: 10.1016/j.micinf.2022.104975] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2021] [Revised: 03/26/2022] [Accepted: 03/28/2022] [Indexed: 12/22/2022]
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9
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Thrombin-Derived C-Terminal Peptide Reduces Candida-Induced Inflammation and Infection In Vitro and In Vivo. Antimicrob Agents Chemother 2021; 65:e0103221. [PMID: 34424043 PMCID: PMC8522777 DOI: 10.1128/aac.01032-21] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023] Open
Abstract
Infections due to the opportunistic fungus Candida have been on the rise in the last decades, especially in immunocompromised individuals and hospital settings. Unfortunately, the treatments available today are limited. Thrombin-derived C-terminal peptide (TCP-25) is an antimicrobial peptide (AMP) with antibacterial and immunomodulatory effects. In this work, we, for the first time, demonstrate the ability of TCP-25 ability to counteract Candidain vitro and in vivo. Using a combination of viable count assay (VCA), radial diffusion assay (RDA), and fluorescence and transmission electron microscopy analyses, TCP-25 was found to exert a direct fungicidal activity. An inhibitory activity of TCP-25 on NF-κB activation induced by both zymosan alone and heat-killed C. albicans was demonstrated in vitro using THP-1 cells, and in vivo using NF-κB reporter mice. Moreover, the immunomodulatory property of TCP-25 was further substantiated in vitro by analyzing cytokine responses in human blood stimulated with zymosan, and in vivo employing a zymosan-induced peritonitis model in C57BL/6 mice. The therapeutic potential of TCP-25 was demonstrated in mice infected with luminescent C. albicans. Finally, the binding between TCP-25 and zymosan was investigated using circular dichroism spectroscopy and intrinsic fluorescence analysis. Taken together, our results show that TCP-25 has a dual function by inhibiting Candida as well as the associated zymosan-induced inflammation. The latter function is accompanied by a change in secondary structure upon binding to zymosan. TCP-25, therefore, shows promise as a novel drug candidate against Candida infections.
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10
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Van Genechten W, Van Dijck P, Demuyser L. Fluorescent toys 'n' tools lighting the way in fungal research. FEMS Microbiol Rev 2021; 45:fuab013. [PMID: 33595628 PMCID: PMC8498796 DOI: 10.1093/femsre/fuab013] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2020] [Accepted: 02/14/2021] [Indexed: 12/13/2022] Open
Abstract
Although largely overlooked compared to bacterial infections, fungal infections pose a significant threat to the health of humans and other organisms. Many pathogenic fungi, especially Candida species, are extremely versatile and flexible in adapting to various host niches and stressful situations. This leads to high pathogenicity and increasing resistance to existing drugs. Due to the high level of conservation between fungi and mammalian cells, it is hard to find fungus-specific drug targets for novel therapy development. In this respect, it is vital to understand how these fungi function on a molecular, cellular as well as organismal level. Fluorescence imaging allows for detailed analysis of molecular mechanisms, cellular structures and interactions on different levels. In this manuscript, we provide researchers with an elaborate and contemporary overview of fluorescence techniques that can be used to study fungal pathogens. We focus on the available fluorescent labelling techniques and guide our readers through the different relevant applications of fluorescent imaging, from subcellular events to multispecies interactions and diagnostics. As well as cautioning researchers for potential challenges and obstacles, we offer hands-on tips and tricks for efficient experimentation and share our expert-view on future developments and possible improvements.
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Affiliation(s)
- Wouter Van Genechten
- VIB-KU Leuven Center for Microbiology, Kasteelpark Arenberg 31, 3001 Leuven-heverlee, Belgium
- Laboratory of Molecular Cell Biology, Institute of Botany and Microbiology, KU Leuven, Kasteelpark Arenberg 31, 3001 Leuven-Heverlee, Belgium
- Laboratory for Nanobiology, Department of Chemistry, KU Leuven, Celestijnenlaan 200g, 3001 Leuven-Heverlee, Belgium
| | - Patrick Van Dijck
- VIB-KU Leuven Center for Microbiology, Kasteelpark Arenberg 31, 3001 Leuven-heverlee, Belgium
- Laboratory of Molecular Cell Biology, Institute of Botany and Microbiology, KU Leuven, Kasteelpark Arenberg 31, 3001 Leuven-Heverlee, Belgium
| | - Liesbeth Demuyser
- VIB-KU Leuven Center for Microbiology, Kasteelpark Arenberg 31, 3001 Leuven-heverlee, Belgium
- Laboratory of Molecular Cell Biology, Institute of Botany and Microbiology, KU Leuven, Kasteelpark Arenberg 31, 3001 Leuven-Heverlee, Belgium
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11
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Vila T, Kong EF, Montelongo-Jauregui D, Van Dijck P, Shetty AC, McCracken C, Bruno VM, Jabra-Rizk MA. Therapeutic implications of C. albicans-S. aureus mixed biofilm in a murine subcutaneous catheter model of polymicrobial infection. Virulence 2021; 12:835-851. [PMID: 33682623 PMCID: PMC7946022 DOI: 10.1080/21505594.2021.1894834] [Citation(s) in RCA: 34] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
Biofilm-associated polymicrobial infections tend to be challenging to treat. Candida albicans and Staphylococcus aureus are leading pathogens due to their ability to form biofilms on medical devices. However, the therapeutic implications of their interactions in a host is largely unexplored. In this study, we used a mouse subcutaneous catheter model for in vivo-grown polymicrobial biofilms to validate our in vitro findings on C. albicans-mediated enhanced S. aureus tolerance to vancomycin in vivo. Comparative assessment of S. aureus recovery from catheters with single- or mixed-species infection demonstrated failure of vancomycin against S. aureus in mice with co-infected catheters. To provide some mechanistic insights, RNA-seq analysis was performed on catheter biofilms to delineate transcriptional modulations during polymicrobial infections. C. albicans induced the activation of the S. aureus biofilm formation network via down-regulation of the lrg operon, repressor of autolysis, and up-regulation of the ica operon and production of polysaccharide intercellular adhesin (PIA), indicating an increase in eDNA production, and extracellular polysaccharide matrix, respectively. Interestingly, virulence factors important for disseminated infections, and superantigen-like proteins were down-regulated during mixed-species infection, whereas capsular polysaccharide genes were up-regulated, signifying a strategy favoring survival, persistence and host immune evasion. In vitro follow-up experiments using DNA enzymatic digestion, lrg operon mutant strains, and confocal scanning microscopy confirmed the role of C. albicans-mediated enhanced eDNA production in mixed-biofilms on S. aureus tolerance to vancomycin. Combined, these findings provide mechanistic insights into the therapeutic implications of interspecies interactions, underscoring the need for novel strategies to overcome limitations of current therapies.
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Affiliation(s)
- Taissa Vila
- Department of Oncology and Diagnostic Sciences, School of Dentistry, University of Maryland, Baltimore, MD, USA
| | - Eric F Kong
- Department of Oncology and Diagnostic Sciences, School of Dentistry, University of Maryland, Baltimore, MD, USA
| | - Daniel Montelongo-Jauregui
- Department of Oncology and Diagnostic Sciences, School of Dentistry, University of Maryland, Baltimore, MD, USA
| | - Patrick Van Dijck
- Laboratory of Molecular Cell Biology, Institute of Botany and Microbiology, KU Leuven, Leuven-Heverlee, Belgium.,VIB-KU Leuven Center for Microbiology, Flanders, Belgium
| | - Amol C Shetty
- Institute for Genome Sciences, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Carrie McCracken
- Institute for Genome Sciences, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Vincent M Bruno
- Institute for Genome Sciences, University of Maryland School of Medicine, Baltimore, MD, USA.,Department of Microbiology and Immunology, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Mary Ann Jabra-Rizk
- Department of Oncology and Diagnostic Sciences, School of Dentistry, University of Maryland, Baltimore, MD, USA.,Department of Microbiology and Immunology, University of Maryland School of Medicine, Baltimore, MD, USA
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12
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D’Hollander A, Vande Velde G, Jans H, Vanspauwen B, Vermeersch E, Jose J, Struys T, Stakenborg T, Lagae L, Himmelreich U. Assessment of the Theranostic Potential of Gold Nanostars-A Multimodal Imaging and Photothermal Treatment Study. NANOMATERIALS 2020; 10:nano10112112. [PMID: 33114177 PMCID: PMC7690792 DOI: 10.3390/nano10112112] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/31/2020] [Revised: 10/19/2020] [Accepted: 10/21/2020] [Indexed: 12/13/2022]
Abstract
Gold nanoparticles offer the possibility to combine both imaging and therapy of otherwise difficult to treat tumors. To validate and further improve their potential, we describe the use of gold nanostars that were functionalized with a polyethyleneglycol-maleimide coating for in vitro and in vivo photoacoustic imaging (PAI), computed tomography (CT), as well as photothermal therapy (PTT) of cancer cells and tumor masses, respectively. Nanostar shaped particles show a high absorption coefficient in the near infrared region and have a hydrodynamic size in biological medium around 100 nm, which allows optimal intra-tumoral retention. Using these nanostars for in vitro labeling of tumor cells, high intracellular nanostar concentrations could be achieved, resulting in high PAI and CT contrast and effective PTT. By injecting the nanostars intratumorally, high contrast could be generated in vivo using PAI and CT, which allowed successful multi-modal tumor imaging. PTT was successfully induced, resulting in tumor cell death and subsequent inhibition of tumor growth. Therefore, gold nanostars are versatile theranostic agents for tumor therapy.
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Affiliation(s)
- Antoine D’Hollander
- Biomedical MRI, Department of Imaging and Pathology, Faculty of Medicine, KU Leuven, Herestraat 49, 3000 Leuven, Belgium; (A.D.); (G.V.V.); (E.V.)
- Molecular Small Animal Imaging Center (MoSAIC), KU Leuven, Herestraat 49, 3000 Leuven, Belgium
- Department of Life Science Technology, IMEC, Kapeldreef 75, 3001 Leuven, Belgium; (H.J.); (B.V.); (T.S.); (L.L.)
| | - Greetje Vande Velde
- Biomedical MRI, Department of Imaging and Pathology, Faculty of Medicine, KU Leuven, Herestraat 49, 3000 Leuven, Belgium; (A.D.); (G.V.V.); (E.V.)
- Molecular Small Animal Imaging Center (MoSAIC), KU Leuven, Herestraat 49, 3000 Leuven, Belgium
| | - Hilde Jans
- Department of Life Science Technology, IMEC, Kapeldreef 75, 3001 Leuven, Belgium; (H.J.); (B.V.); (T.S.); (L.L.)
| | - Bram Vanspauwen
- Department of Life Science Technology, IMEC, Kapeldreef 75, 3001 Leuven, Belgium; (H.J.); (B.V.); (T.S.); (L.L.)
| | - Elien Vermeersch
- Biomedical MRI, Department of Imaging and Pathology, Faculty of Medicine, KU Leuven, Herestraat 49, 3000 Leuven, Belgium; (A.D.); (G.V.V.); (E.V.)
- Molecular Small Animal Imaging Center (MoSAIC), KU Leuven, Herestraat 49, 3000 Leuven, Belgium
| | - Jithin Jose
- Fujifilm Visualsonics, Joop Geesinkweg140, 1114 AB Amsterdam, The Netherlands;
| | - Tom Struys
- Lab of Histology, Biomedical Research Institute, Hasselt University, Agora Laan Gebouw C, 3590 Diepenbeek, Belgium;
| | - Tim Stakenborg
- Department of Life Science Technology, IMEC, Kapeldreef 75, 3001 Leuven, Belgium; (H.J.); (B.V.); (T.S.); (L.L.)
| | - Liesbet Lagae
- Department of Life Science Technology, IMEC, Kapeldreef 75, 3001 Leuven, Belgium; (H.J.); (B.V.); (T.S.); (L.L.)
- Department of Physics, Faculty of Sciences, Laboratory of Soft Matter and Biophysics, KU Leuven, Celestijnenlaan 200D, 3001 Leuven, Belgium
| | - Uwe Himmelreich
- Biomedical MRI, Department of Imaging and Pathology, Faculty of Medicine, KU Leuven, Herestraat 49, 3000 Leuven, Belgium; (A.D.); (G.V.V.); (E.V.)
- Molecular Small Animal Imaging Center (MoSAIC), KU Leuven, Herestraat 49, 3000 Leuven, Belgium
- Correspondence: ; Tel.: +32-16-330925
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13
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Dimond A, Van de Pette M, Fisher AG. Illuminating Epigenetics and Inheritance in the Immune System with Bioluminescence. Trends Immunol 2020; 41:994-1005. [PMID: 33036908 DOI: 10.1016/j.it.2020.09.001] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2020] [Revised: 09/08/2020] [Accepted: 09/08/2020] [Indexed: 12/25/2022]
Abstract
The remarkable process of light emission by living organisms has fascinated mankind for thousands of years. A recent expansion in the repertoire of catalytic luciferase enzymes, coupled with the discovery of the genes and pathways that encode different luciferin substrates, means that bioluminescence imaging (BLI) is set to revolutionize longitudinal and dynamic studies of gene control within biomedicine, including the regulation of immune responses. In this review article, we summarize recent advances in bioluminescence-based imaging approaches that promise to enlighten our understanding of in vivo gene and epigenetic control within the immune system.
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Affiliation(s)
- Andrew Dimond
- Lymphocyte Development Group, MRC London Institute of Medical Sciences, Imperial College London, Hammersmith Hospital Campus, Du Cane Road, London, W12 0NN, UK
| | - Mathew Van de Pette
- Epigenetic Mechanisms of Toxicity, MRC Toxicology Unit, University of Cambridge, Downing Street, Cambridge, CB2 3EH, UK
| | - Amanda G Fisher
- Lymphocyte Development Group, MRC London Institute of Medical Sciences, Imperial College London, Hammersmith Hospital Campus, Du Cane Road, London, W12 0NN, UK.
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14
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Ryan LK, Hise AG, Hossain CM, Ruddick W, Parveen R, Freeman KB, Weaver DG, Narra HP, Scott RW, Diamond G. A Novel Immunocompetent Mouse Model for Testing Antifungal Drugs Against Invasive Candida albicans Infection. J Fungi (Basel) 2020; 6:E197. [PMID: 33007818 PMCID: PMC7712810 DOI: 10.3390/jof6040197] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2020] [Revised: 09/22/2020] [Accepted: 09/28/2020] [Indexed: 12/12/2022] Open
Abstract
Disseminated infection by Candida species represents a common, often life-threatening condition. Increased resistance to current antifungal drugs has led to an urgent need to develop new antifungal drugs to treat this pathogen. However, in vivo screening of candidate antifungal compounds requires large numbers of animals and using immunosuppressive agents to allow for fungal dissemination. To increase the efficiency of screening, to use fewer mice, and to remove the need for immunosuppressive agents, which may interfere with the drug candidates, we tested the potential for a novel approach using in vivo imaging of a fluorescent strain of Candida albicans, in a mouse strain deficient in the host defense peptide, murine β-defensin 1 (mBD-1). We developed a strain of C. albicans that expresses red fluorescent protein (RFP), which exhibits similar infectivity to the non-fluorescent parent strain. When this strain was injected into immunocompetent mBD-1-deficient mice, we observed a non-lethal disseminated infection. Further, we could quantify its dissemination in real time, and observe the activity of an antifungal peptide mimetic drug by in vivo imaging. This novel method will allow for the rapid in vivo screening of antifungal drugs, using fewer mice, and increase the efficiency of testing new antifungal agents.
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Affiliation(s)
- Lisa K. Ryan
- Division of Infectious Disease and Global Medicine, Department of Medicine, University of Florida College of Medicine, Gainesville, FL 32610, USA;
| | - Amy G Hise
- Department of Pathology, Case Western Reserve University School of Medicine, Cleveland, OH 44106, USA;
- Medicine Service, Louis Stokes Cleveland VA Medical Center, Cleveland, OH 44106, USA
| | - Chowdhury Mobaswar Hossain
- Department of Oral Biology, University of Florida College of Dentistry, Gainesville, FL 32610, USA; (C.M.H.); (W.R.); (R.P.)
| | - William Ruddick
- Department of Oral Biology, University of Florida College of Dentistry, Gainesville, FL 32610, USA; (C.M.H.); (W.R.); (R.P.)
| | - Rezwana Parveen
- Department of Oral Biology, University of Florida College of Dentistry, Gainesville, FL 32610, USA; (C.M.H.); (W.R.); (R.P.)
| | - Katie B. Freeman
- Fox Chase Chemical Diversity Center, Inc., Pennsylvania Biotechnology Center, Doylestown, PA 18902, USA; (K.B.F.); (D.G.W.); (R.W.S.)
| | - Damian G. Weaver
- Fox Chase Chemical Diversity Center, Inc., Pennsylvania Biotechnology Center, Doylestown, PA 18902, USA; (K.B.F.); (D.G.W.); (R.W.S.)
| | - Hema P. Narra
- Department of Pathology, University of Texas Medical Branch, Galveston, TX 77555, USA;
| | - Richard W. Scott
- Fox Chase Chemical Diversity Center, Inc., Pennsylvania Biotechnology Center, Doylestown, PA 18902, USA; (K.B.F.); (D.G.W.); (R.W.S.)
| | - Gill Diamond
- Department of Oral Biology, University of Florida College of Dentistry, Gainesville, FL 32610, USA; (C.M.H.); (W.R.); (R.P.)
- Department of Oral Immunology and Infectious Diseases, University of Louisville School of Dentistry, Louisville, KY 40902, USA
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15
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The Added Value of Longitudinal Imaging for Preclinical In Vivo Efficacy Testing of Therapeutic Compounds against Cerebral Cryptococcosis. Antimicrob Agents Chemother 2020; 64:AAC.00070-20. [PMID: 32284382 DOI: 10.1128/aac.00070-20] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2020] [Accepted: 04/04/2020] [Indexed: 02/07/2023] Open
Abstract
Brain infections with Cryptococcus neoformans are associated with significant morbidity and mortality. Cryptococcosis typically presents as meningoencephalitis or fungal mass lesions called cryptococcomas. Despite frequent in vitro discoveries of promising novel antifungals, the clinical need for drugs that can more efficiently treat these brain infections remains. A crucial step in drug development is the evaluation of in vivo drug efficacy in animal models. This mainly relies on survival studies or postmortem analyses in large groups of animals, but these techniques only provide information on specific organs of interest at predefined time points. In this proof-of-concept study, we validated the use of noninvasive preclinical imaging to obtain longitudinal information on the therapeutic efficacy of amphotericin B or fluconazole monotherapy in meningoencephalitis and cryptococcoma mouse models. Bioluminescence imaging enabled the rapid in vitro and in vivo evaluation of drug efficacy, while complementary high-resolution anatomical information obtained by magnetic resonance imaging of the brain allowed a precise assessment of the extent of infection and lesion growth rates. We demonstrated a good correlation between both imaging readouts and the fungal burden in various organs. Moreover, we identified potential pitfalls associated with the interpretation of therapeutic efficacy based solely on postmortem studies, demonstrating the added value of this noninvasive dual imaging approach compared to standard mortality curves or fungal load endpoints. This novel preclinical imaging platform provides insights in the dynamic aspects of the therapeutic response and facilitates a more efficient and accurate translation of promising antifungal compounds from bench to bedside.
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16
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Vanherp L, Ristani A, Poelmans J, Hillen A, Lagrou K, Janbon G, Brock M, Himmelreich U, Vande Velde G. Sensitive bioluminescence imaging of fungal dissemination to the brain in mouse models of cryptococcosis. Dis Model Mech 2019; 12:dmm.039123. [PMID: 31101657 PMCID: PMC6602310 DOI: 10.1242/dmm.039123] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2019] [Accepted: 05/08/2019] [Indexed: 12/18/2022] Open
Abstract
Cryptococcus neoformans is a leading cause of fungal brain infection, but the mechanism of dissemination and dynamics of cerebral infection following pulmonary disease are poorly understood. To address these questions, non-invasive techniques that can study the dynamic processes of disease development and progression in living animal models or patients are required. As such, bioluminescence imaging (BLI) has emerged as a powerful tool to evaluate the spatial and temporal distribution of infection in living animals. We aimed to study the time profile of the dissemination of cryptococcosis from the lung to the brain in murine models by engineering the first bioluminescent C. neoformans KN99α strain, expressing a sequence-optimized red-shifted luciferase. The high pathogen specificity and sensitivity of BLI was complemented by the three-dimensional anatomical information from micro-computed tomography (μCT) of the lung and magnetic resonance imaging (MRI) of the brain. These non-invasive imaging techniques provided longitudinal readouts on the spatial and temporal distribution of infection following intravenous, intranasal or endotracheal routes of inoculation. Furthermore, the imaging results correlated strongly with the fungal load in the respective organs. By obtaining dynamic and quantitative information about the extent and timing of brain infections for individual animals, we found that dissemination to the brain after primary infection of the lung is likely a late-stage event with a timeframe that is variable between animals. This novel tool in Cryptococcus research can aid the identification of host and pathogen factors involved in this process, and supports development of novel preventive or therapeutic approaches. Summary: A novel combination of bioluminescence and anatomical imaging non-invasively identified the timeframe and extent of Cryptococcus neoformans dissemination to the brain in animal models of systemic and pulmonary fungal infection.
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Affiliation(s)
- Liesbeth Vanherp
- Biomedical MRI, Department of Imaging and Pathology, KU Leuven, 3000 Leuven, Belgium.,Molecular Small Animal Imaging Center (MoSAIC), KU Leuven, 3000 Leuven, Belgium
| | - Alexandra Ristani
- Biomedical MRI, Department of Imaging and Pathology, KU Leuven, 3000 Leuven, Belgium.,Molecular Small Animal Imaging Center (MoSAIC), KU Leuven, 3000 Leuven, Belgium
| | - Jennifer Poelmans
- Biomedical MRI, Department of Imaging and Pathology, KU Leuven, 3000 Leuven, Belgium.,Molecular Small Animal Imaging Center (MoSAIC), KU Leuven, 3000 Leuven, Belgium
| | - Amy Hillen
- Biomedical MRI, Department of Imaging and Pathology, KU Leuven, 3000 Leuven, Belgium.,Molecular Small Animal Imaging Center (MoSAIC), KU Leuven, 3000 Leuven, Belgium
| | - Katrien Lagrou
- Laboratory of Clinical Bacteriology and Mycology, Department of Microbiology and Immunology, KU Leuven, 3000 Leuven, Belgium
| | - Guilhem Janbon
- RNA Biology of Fungal Pathogens, Department of Mycology, Pasteur Institute, Paris 75015, France
| | - Matthias Brock
- Fungal Biology Group, School of Life Sciences, University of Nottingham, Nottingham NG7 2RD, UK
| | - Uwe Himmelreich
- Biomedical MRI, Department of Imaging and Pathology, KU Leuven, 3000 Leuven, Belgium.,Molecular Small Animal Imaging Center (MoSAIC), KU Leuven, 3000 Leuven, Belgium
| | - Greetje Vande Velde
- Biomedical MRI, Department of Imaging and Pathology, KU Leuven, 3000 Leuven, Belgium .,Molecular Small Animal Imaging Center (MoSAIC), KU Leuven, 3000 Leuven, Belgium
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17
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Salinas B, Guembe M, Cussó L, Kestler M, Guinea J, Desco M, Muñoz P, Bouza E. Assessment of the anti-biofilm effect of micafungin in an animal model of catheter-related candidemia. Med Mycol 2019; 57:496-503. [DOI: 10.1093/mmy/myy065] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2018] [Revised: 06/22/2018] [Accepted: 07/16/2018] [Indexed: 11/14/2022] Open
Affiliation(s)
- Beatriz Salinas
- Instituto de Investigación Sanitaria Gregorio Marañón, Madrid, Spain
- Centro Nacional de Investigaciones Cardiovasculares Carlos III (CNIC), Madrid, Spain
| | - María Guembe
- Instituto de Investigación Sanitaria Gregorio Marañón, Madrid, Spain
- Servicio de Microbiología y Enfermedades Infecciosas, Hospital General Universitario Gregorio Marañón, Madrid, Spain
| | - Lorena Cussó
- Instituto de Investigación Sanitaria Gregorio Marañón, Madrid, Spain
- Departamento de Bioingeniería e Ingeniería Aeroespacial, Universidad Carlos III de Madrid, Madrid, Spain
- Centro Nacional de Investigaciones Cardiovasculares Carlos III (CNIC), Madrid, Spain
- Centro de Investigación Biomédica en Red de Salud Mental (CIBERSAM), Spain
| | - Martha Kestler
- Instituto de Investigación Sanitaria Gregorio Marañón, Madrid, Spain
| | - Jesús Guinea
- Instituto de Investigación Sanitaria Gregorio Marañón, Madrid, Spain
- Servicio de Microbiología y Enfermedades Infecciosas, Hospital General Universitario Gregorio Marañón, Madrid, Spain
- Departamento de Medicina, Facultad de Medicina, Universidad Complutense de Madrid, Madrid, Spain
| | - Manuel Desco
- Instituto de Investigación Sanitaria Gregorio Marañón, Madrid, Spain
- Departamento de Bioingeniería e Ingeniería Aeroespacial, Universidad Carlos III de Madrid, Madrid, Spain
- Centro Nacional de Investigaciones Cardiovasculares Carlos III (CNIC), Madrid, Spain
- Centro de Investigación Biomédica en Red de Salud Mental (CIBERSAM), Spain
| | - Patricia Muñoz
- Instituto de Investigación Sanitaria Gregorio Marañón, Madrid, Spain
- Servicio de Microbiología y Enfermedades Infecciosas, Hospital General Universitario Gregorio Marañón, Madrid, Spain
- Departamento de Medicina, Facultad de Medicina, Universidad Complutense de Madrid, Madrid, Spain
- CIBER Enfermedades Respiratorias-CIBERES (CB06/06/0058), Madrid, Spain
| | - Emilio Bouza
- Instituto de Investigación Sanitaria Gregorio Marañón, Madrid, Spain
- Servicio de Microbiología y Enfermedades Infecciosas, Hospital General Universitario Gregorio Marañón, Madrid, Spain
- Departamento de Medicina, Facultad de Medicina, Universidad Complutense de Madrid, Madrid, Spain
- CIBER Enfermedades Respiratorias-CIBERES (CB06/06/0058), Madrid, Spain
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18
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Monitoring of Fluconazole and Caspofungin Activity against In Vivo Candida glabrata Biofilms by Bioluminescence Imaging. Antimicrob Agents Chemother 2019; 63:AAC.01555-18. [PMID: 30420485 DOI: 10.1128/aac.01555-18] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2018] [Accepted: 10/27/2018] [Indexed: 12/25/2022] Open
Abstract
Candida glabrata can attach to various medical implants and forms thick biofilms despite its inability to switch from yeast to hyphae. The current in vivo C. glabrata biofilm models only provide limited information about colonization and infection and usually require animal sacrifice. To gain real-time information from individual BALB/c mice, we developed a noninvasive imaging technique to visualize C. glabrata biofilms in catheter fragments that were subcutaneously implanted on the back of mice. Bioluminescent C. glabrata reporter strains (luc OPT 7/2/4 and luc OPT 8/1/4), free of auxotrophic markers, expressing a codon-optimized firefly luciferase were generated. A murine subcutaneous model was used to follow real-time in vivo biofilm formation in the presence and absence of fluconazole and caspofungin. The fungal load in biofilms was quantified by CFU counts and by bioluminescence imaging (BLI). C. glabrata biofilms formed within the first 24 h, as documented by the increased number of device-associated cells and elevated bioluminescent signal compared with adhesion at the time of implant. The in vivo model allowed monitoring of the antibiofilm activity of caspofungin against C. glabrata biofilms through bioluminescent imaging from day four after the initiation of treatment. Contrarily, signals emitted from biofilms implanted in fluconazole-treated mice were similar to the light emitted from control-treated mice. This study gives insights into the real-time development of C. glabrata biofilms under in vivo conditions. BLI proved to be a dynamic, noninvasive, and sensitive tool to monitor continuous biofilm formation and activity of antifungal agents against C. glabrata biofilms formed on abiotic surfaces in vivo.
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19
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Seleem D, Freitas-Blanco VS, Noguti J, Zancope BR, Pardi V, Murata RM. In Vivo Antifungal Activity of Monolaurin against Candida albicans Biofilms. Biol Pharm Bull 2018; 41:1299-1302. [PMID: 30068882 DOI: 10.1248/bpb.b18-00256] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Monolaurin is a natural compound that has been known for its broad antimicrobial activities. We evaluate the antifungal activity of monolaurin against Candida albicans biofilms in vivo using a novel bioluminescent model to longitudinally monitor oral fungal infection. Oral fungal infection in vivo was performed using bioluminescent engineered C. albicans (SKCa23-ActgLUC) biofilms on Balb/c mice. The antifungal activity of monolaurin was determined by comparing three groups of mice (n=5/group): monolaurin, vehicle control, and positive control (nystatin). All mice were immunosuppressed with cortisone acetate and oral topical treatments were applied for 5 d. In vivo imaging system (IVIS) imaging was used to monitor the progression of infection over a 5-d period. Total photon flux and ex vivo microbiological analysis of the excised tongues were used to determine the overall fungal burden. Oral topical treatments of monolaurin have resulted in a significant decrease (p<0.05) in the total photon flux over 4 and 5 d post-infection in comparison to the vehicle control group. Furthermore, monolaurin treated group had a significant decrease in colony formation unit of tongue tissue compared to the vehicle control. Our findings support monolaurin as a promising antifungal compound in vivo, which may translate to its future use in the treatment of oral candidiasis.
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Affiliation(s)
- Dalia Seleem
- Western University of Health Sciences, College of Dental Medicine
| | | | - Juliana Noguti
- Ostrow School of Dentistry, University of Southern California
| | - Bruna Raquel Zancope
- Department of Physiological Sciences, Piracicaba Dental School, University of Campinas
| | - Vanessa Pardi
- Ostrow School of Dentistry, University of Southern California
| | - Ramiro Mendonça Murata
- Department of Foundational Sciences, School of Dental Medicine, East Carolina University.,Department of Microbiology and Immunology, Brody School of Medicine, East Carolina University
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20
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Pericolini E, Colombari B, Ferretti G, Iseppi R, Ardizzoni A, Girardis M, Sala A, Peppoloni S, Blasi E. Real-time monitoring of Pseudomonas aeruginosa biofilm formation on endotracheal tubes in vitro. BMC Microbiol 2018; 18:84. [PMID: 30107778 PMCID: PMC6092828 DOI: 10.1186/s12866-018-1224-6] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2018] [Accepted: 07/30/2018] [Indexed: 11/24/2022] Open
Abstract
Background Pseudomonas aeruginosa is an opportunistic bacterial pathogen responsible for both acute and chronic infections in humans. In particular, its ability to form biofilm, on biotic and abiotic surfaces, makes it particularly resistant to host’s immune defenses and current antibiotic therapies as well. Innovative antimicrobial materials, like hydrogel, silver salts or nanoparticles have been used to cover new generation catheters with promising results. Nevertheless, biofilm remains a major health problem. For instance, biofilm produced onto endotracheal tubes (ETT) of ventilated patients plays a relevant role in the onset of ventilation-associated pneumonia. Most of our knowledge on Pseudomonas aeruginosa biofilm derives from in vitro studies carried out on abiotic surfaces, such as polystyrene microplates or plastic materials used for ETT manufacturing. However, these approaches often provide underestimated results since other parameters, in addition to bacterial features (i.e. shape and material composition of ETT) might strongly influence biofilm formation. Results We used an already established biofilm development assay on medically-relevant foreign devices (CVC catheters) by a stably transformed bioluminescent (BLI)-Pseudomonas aeruginosa strain, in order to follow up biofilm formation on ETT by bioluminescence detection. Our results demonstrated that it is possible: i) to monitor BLI-Pseudomonas aeruginosa biofilm development on ETT pieces in real-time, ii) to evaluate the three-dimensional structure of biofilm directly on ETT, iii) to assess metabolic behavior and the production of microbial virulence traits of bacteria embedded on ETT-biofilm. Conclusions Overall, we were able to standardize a rapid and easy-to-perform in vitro model for real-time monitoring Pseudomonas aeruginosa biofilm formation directly onto ETT pieces, taking into account not only microbial factors, but also ETT shape and material. Our study provides a rapid method for future screening and validation of novel antimicrobial drugs as well as for the evaluation of novel biomaterials employed in the production of new classes of ETT. Electronic supplementary material The online version of this article (10.1186/s12866-018-1224-6) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Eva Pericolini
- Department of Surgical, Medical, Dental and Morphological Sciences with interest in Transplant, Oncological and Regenerative Medicine, University of Modena and Reggio Emilia, Modena, Italy.
| | - Bruna Colombari
- Department of Surgical, Medical, Dental and Morphological Sciences with interest in Transplant, Oncological and Regenerative Medicine, University of Modena and Reggio Emilia, Modena, Italy
| | - Gianmarco Ferretti
- Department of Surgical, Medical, Dental and Morphological Sciences with interest in Transplant, Oncological and Regenerative Medicine, University of Modena and Reggio Emilia, Modena, Italy
| | - Ramona Iseppi
- Department of Life Sciences, University of Modena and Reggio Emilia, Modena, Italy
| | - Andrea Ardizzoni
- Department of Surgical, Medical, Dental and Morphological Sciences with interest in Transplant, Oncological and Regenerative Medicine, University of Modena and Reggio Emilia, Modena, Italy
| | - Massimo Girardis
- Department of Surgical, Medical, Dental and Morphological Sciences with interest in Transplant, Oncological and Regenerative Medicine, University of Modena and Reggio Emilia, Modena, Italy
| | - Arianna Sala
- Department of Surgical, Medical, Dental and Morphological Sciences with interest in Transplant, Oncological and Regenerative Medicine, University of Modena and Reggio Emilia, Modena, Italy
| | - Samuele Peppoloni
- Department of Surgical, Medical, Dental and Morphological Sciences with interest in Transplant, Oncological and Regenerative Medicine, University of Modena and Reggio Emilia, Modena, Italy
| | - Elisabetta Blasi
- Department of Surgical, Medical, Dental and Morphological Sciences with interest in Transplant, Oncological and Regenerative Medicine, University of Modena and Reggio Emilia, Modena, Italy
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21
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Vande Velde G, Kucharíková S, Van Dijck P, Himmelreich U. Bioluminescence imaging increases in vivo screening efficiency for antifungal activity against device-associated Candida albicans biofilms. Int J Antimicrob Agents 2018; 52:42-51. [DOI: 10.1016/j.ijantimicag.2018.03.007] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2017] [Revised: 03/01/2018] [Accepted: 03/11/2018] [Indexed: 11/29/2022]
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22
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Van Dijck P, Sjollema J, Cammue BPA, Lagrou K, Berman J, d’Enfert C, Andes DR, Arendrup MC, Brakhage AA, Calderone R, Cantón E, Coenye T, Cos P, Cowen LE, Edgerton M, Espinel-Ingroff A, Filler SG, Ghannoum M, Gow NA, Haas H, Jabra-Rizk MA, Johnson EM, Lockhart SR, Lopez-Ribot JL, Maertens J, Munro CA, Nett JE, Nobile CJ, Pfaller MA, Ramage G, Sanglard D, Sanguinetti M, Spriet I, Verweij PE, Warris A, Wauters J, Yeaman MR, Zaat SA, Thevissen K. Methodologies for in vitro and in vivo evaluation of efficacy of antifungal and antibiofilm agents and surface coatings against fungal biofilms. MICROBIAL CELL (GRAZ, AUSTRIA) 2018; 5:300-326. [PMID: 29992128 PMCID: PMC6035839 DOI: 10.15698/mic2018.07.638] [Citation(s) in RCA: 66] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/07/2018] [Accepted: 05/24/2018] [Indexed: 12/13/2022]
Abstract
Unlike superficial fungal infections of the skin and nails, which are the most common fungal diseases in humans, invasive fungal infections carry high morbidity and mortality, particularly those associated with biofilm formation on indwelling medical devices. Therapeutic management of these complex diseases is often complicated by the rise in resistance to the commonly used antifungal agents. Therefore, the availability of accurate susceptibility testing methods for determining antifungal resistance, as well as discovery of novel antifungal and antibiofilm agents, are key priorities in medical mycology research. To direct advancements in this field, here we present an overview of the methods currently available for determining (i) the susceptibility or resistance of fungal isolates or biofilms to antifungal or antibiofilm compounds and compound combinations; (ii) the in vivo efficacy of antifungal and antibiofilm compounds and compound combinations; and (iii) the in vitro and in vivo performance of anti-infective coatings and materials to prevent fungal biofilm-based infections.
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Affiliation(s)
- Patrick Van Dijck
- VIB-KU Leuven Center for Microbiology, Leuven, Belgium
- KU Leuven Laboratory of Molecular Cell Biology, Leuven, Belgium
| | - Jelmer Sjollema
- University of Groningen, University Medical Center Groningen, Department of BioMedical Engineering, Groningen, The Netherlands
| | - Bruno P. A. Cammue
- Centre for Microbial and Plant Genetics, KU Leuven, Leuven, Belgium
- Department of Plant Systems Biology, VIB, Ghent, Belgium
| | - Katrien Lagrou
- Department of Microbiology and Immunology, KU Leuven, Leuven, Belgium
- Clinical Department of Laboratory Medicine and National Reference Center for Mycosis, UZ Leuven, Belgium
| | - Judith Berman
- School of Molecular Cell Biology and Biotechnology, Faculty of Life Sciences, Tel Aviv University, Ramat Aviv, Israel
| | - Christophe d’Enfert
- Institut Pasteur, INRA, Unité Biologie et Pathogénicité Fongiques, Paris, France
| | - David R. Andes
- Department of Medical Microbiology and Immunology, University of Wisconsin-Madison, Madison, Wisconsin, USA
- Department of Medicine, University of Wisconsin-Madison, Madison, Wisconsin, USA
| | - Maiken C. Arendrup
- Unit of Mycology, Statens Serum Institut, Copenhagen, Denmark
- Department of Clinical Microbiology, Rigshospitalet, Copenhagen, Denmark
- Department of Clinical Medicine, University of Copenhagen, Copenhagen, Denmark
| | - Axel A. Brakhage
- Leibniz Institute for Natural Product Research and Infection Biology - Hans Knoell Institute (HKI), Dept. Microbiology and Molecular Biology, Friedrich Schiller University Jena, Institute of Microbiology, Jena, Germany
| | - Richard Calderone
- Department of Microbiology & Immunology, Georgetown University Medical Center, Washington DC, USA
| | - Emilia Cantón
- Severe Infection Research Group: Medical Research Institute La Fe (IISLaFe), Valencia, Spain
| | - Tom Coenye
- Laboratory of Pharmaceutical Microbiology, Ghent University, Ghent, Belgium
- ESCMID Study Group for Biofilms, Switzerland
| | - Paul Cos
- Laboratory for Microbiology, Parasitology and Hygiene (LMPH), University of Antwerp, Belgium
| | - Leah E. Cowen
- Department of Molecular Genetics, University of Toronto, Toronto, Ontario, Canada
| | - Mira Edgerton
- Department of Oral Biology, School of Dental Medicine, University at Buffalo, Buffalo, NY USA
| | | | - Scott G. Filler
- Division of Infectious Diseases, Los Angeles Biomedical Research Institute at Harbor-UCLA Medical Center, Torrance, CA, USA
| | - Mahmoud Ghannoum
- Center for Medical Mycology, Department of Dermatology, University Hospitals Cleveland Medical Center and Case Western Re-serve University, Cleveland, OH, USA
| | - Neil A.R. Gow
- MRC Centre for Medical Mycology, Institute of Medical Sciences, University of Aberdeen, Aberdeen, UK
| | - Hubertus Haas
- Biocenter - Division of Molecular Biology, Medical University Innsbruck, Innsbruck, Austria
| | - Mary Ann Jabra-Rizk
- Department of Oncology and Diagnostic Sciences, School of Dentistry; Department of Microbiology and Immunology, School of Medicine, University of Maryland, Baltimore, USA
| | - Elizabeth M. Johnson
- National Infection Service, Public Health England, Mycology Reference Laboratory, Bristol, UK
| | | | | | - Johan Maertens
- Department of Microbiology and Immunology, KU Leuven, Leuven, Belgium and Clinical Department of Haematology, UZ Leuven, Leuven, Belgium
| | - Carol A. Munro
- MRC Centre for Medical Mycology, Institute of Medical Sciences, University of Aberdeen, Aberdeen, UK
| | - Jeniel E. Nett
- University of Wisconsin-Madison, Departments of Medicine and Medical Microbiology & Immunology, Madison, WI, USA
| | - Clarissa J. Nobile
- Department of Molecular and Cell Biology, School of Natural Sciences, University of California, Merced, Merced, USA
| | - Michael A. Pfaller
- Departments of Pathology and Epidemiology, University of Iowa, Iowa, USA
- JMI Laboratories, North Liberty, Iowa, USA
| | - Gordon Ramage
- ESCMID Study Group for Biofilms, Switzerland
- College of Medical, Veterinary and Life Sciences, University of Glasgow, UK
| | - Dominique Sanglard
- Institute of Microbiology, University of Lausanne and University Hospital, CH-1011 Lausanne
| | - Maurizio Sanguinetti
- Institute of Microbiology, Università Cattolica del Sacro Cuore, IRCCS-Fondazione Policlinico "Agostino Gemelli", Rome, Italy
| | - Isabel Spriet
- Pharmacy Dpt, University Hospitals Leuven and Clinical Pharmacology and Pharmacotherapy, Dpt. of Pharmaceutical and Pharma-cological Sciences, KU Leuven, Belgium
| | - Paul E. Verweij
- Center of Expertise in Mycology Radboudumc/CWZ, Radboud University Medical Center, Nijmegen, the Netherlands (omit "Nijmegen" in Radboud University Medical Center)
| | - Adilia Warris
- MRC Centre for Medical Mycology, Aberdeen Fungal Group, University of Aberdeen, Foresterhill, Aberdeen, UK
| | - Joost Wauters
- KU Leuven-University of Leuven, University Hospitals Leuven, Department of General Internal Medicine, Herestraat 49, B-3000 Leuven, Belgium
| | - Michael R. Yeaman
- Geffen School of Medicine at the University of California, Los Angeles, Divisions of Molecular Medicine & Infectious Diseases, Har-bor-UCLA Medical Center, LABioMed at Harbor-UCLA Medical Center
| | - Sebastian A.J. Zaat
- Department of Medical Microbiology, Amsterdam Infection and Immunity Institute, Academic Medical Center, University of Am-sterdam, Netherlands
| | - Karin Thevissen
- Centre for Microbial and Plant Genetics, KU Leuven, Leuven, Belgium
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Antifungal Potential of Host Defense Peptide Mimetics in a Mouse Model of Disseminated Candidiasis. J Fungi (Basel) 2018; 4:jof4010030. [PMID: 29495524 PMCID: PMC5872333 DOI: 10.3390/jof4010030] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2018] [Revised: 02/21/2018] [Accepted: 02/24/2018] [Indexed: 12/14/2022] Open
Abstract
Invasive candidiasis caused by Candida albicans and non-albicansCandida (NAC) present a serious disease threat. Although the echinocandins are recommended as the first line of antifungal drug class, resistance to these agents is beginning to emerge, demonstrating the need for new antifungal agents. Host defense peptides (HDP) exhibit potent antifungal activity, but as drugs they are difficult to manufacture efficiently, and they are often inactivated by serum proteins. HDP mimetics are low molecular weight non-peptide compounds that can alleviate these problems and were shown to be membrane-active against C. albicans and NAC. Here, we expand upon our previous works to describe the in vitro and in vivo activity of 11 new HDP mimetics that are active against C. albicans and NAC that are both sensitive and resistant to standard antifungal drugs. These compounds exhibit minimum inhibitory/fungicidal concentration (MIC/MFC) in the µg/mL range in the presence of serum and are inhibited by divalent cations. Rapid propidium iodide influx into the yeast cells following in vitro exposure suggested that these HDP mimetics were also membrane active. The lead compounds were able to kill C. albicans in an invasive candidiasis CD-1 mouse model with some mimetic candidates decreasing kidney burden by 3–4 logs after 24 h in a dose-dependent manner. The data encouraged further development of this new anti-fungal drug class for invasive candidiasis.
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Avci P, Karimi M, Sadasivam M, Antunes-Melo WC, Carrasco E, Hamblin MR. In-vivo monitoring of infectious diseases in living animals using bioluminescence imaging. Virulence 2017; 9:28-63. [PMID: 28960132 PMCID: PMC6067836 DOI: 10.1080/21505594.2017.1371897] [Citation(s) in RCA: 39] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
Traditional methods of localizing and quantifying the presence of pathogenic microorganisms in living experimental animal models of infections have mostly relied on sacrificing the animals, dissociating the tissue and counting the number of colony forming units. However, the discovery of several varieties of the light producing enzyme, luciferase, and the genetic engineering of bacteria, fungi, parasites and mice to make them emit light, either after administration of the luciferase substrate, or in the case of the bacterial lux operon without any exogenous substrate, has provided a new alternative. Dedicated bioluminescence imaging (BLI) cameras can record the light emitted from living animals in real time allowing non-invasive, longitudinal monitoring of the anatomical location and growth of infectious microorganisms as measured by strength of the BLI signal. BLI technology has been used to follow bacterial infections in traumatic skin wounds and burns, osteomyelitis, infections in intestines, Mycobacterial infections, otitis media, lung infections, biofilm and endodontic infections and meningitis. Fungi that have been engineered to be bioluminescent have been used to study infections caused by yeasts (Candida) and by filamentous fungi. Parasitic infections caused by malaria, Leishmania, trypanosomes and toxoplasma have all been monitored by BLI. Viruses such as vaccinia, herpes simplex, hepatitis B and C and influenza, have been studied using BLI. This rapidly growing technology is expected to continue to provide much useful information, while drastically reducing the numbers of animals needed in experimental studies.
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Affiliation(s)
- Pinar Avci
- a Wellman Center for Photomedicine, Massachusetts General Hospital , Boston , MA , USA.,b Department of Dermatology , Harvard Medical School , Boston , MA , USA
| | - Mahdi Karimi
- a Wellman Center for Photomedicine, Massachusetts General Hospital , Boston , MA , USA.,c Department of Medical Nanotechnology , School of Advanced Technologies in Medicine, Iran University of Medical Sciences , Tehran , Iran.,d Cellular and Molecular Research Center, Iran University of Medical Sciences , Tehran , Iran
| | - Magesh Sadasivam
- a Wellman Center for Photomedicine, Massachusetts General Hospital , Boston , MA , USA.,e Amity Institute of Nanotechnology, Amity University Uttar Pradesh , Noida , India
| | - Wanessa C Antunes-Melo
- a Wellman Center for Photomedicine, Massachusetts General Hospital , Boston , MA , USA.,f University of Sao Paulo , Sao Carlos-SP , Brazil
| | - Elisa Carrasco
- a Wellman Center for Photomedicine, Massachusetts General Hospital , Boston , MA , USA.,g Department of Biosciences , Durham University , Durham , United Kingdom
| | - Michael R Hamblin
- a Wellman Center for Photomedicine, Massachusetts General Hospital , Boston , MA , USA.,b Department of Dermatology , Harvard Medical School , Boston , MA , USA.,h Harvard-MIT Division of Health Sciences and Technology , Cambridge , MA , USA
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Abstract
Candida albicans is among the most prevalent fungal species of the human microbiota and asymptomatically colonizes healthy individuals. However, it is also an opportunistic pathogen that can cause severe, and often fatal, bloodstream infections. The medical impact of C. albicans typically depends on its ability to form biofilms, which are closely packed communities of cells that attach to surfaces, such as tissues and implanted medical devices. In this Review, we provide an overview of the processes involved in the formation of C. albicans biofilms and discuss the core transcriptional network that regulates biofilm development. We also consider some of the advantages that biofilms provide to C. albicans in comparison with planktonic growth and explore polymicrobial biofilms that are formed by C. albicans and certain bacterial species.
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Dorsaz S, Coste AT, Sanglard D. Red-Shifted Firefly Luciferase Optimized for Candida albicans In vivo Bioluminescence Imaging. Front Microbiol 2017; 8:1478. [PMID: 28824601 PMCID: PMC5541039 DOI: 10.3389/fmicb.2017.01478] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2017] [Accepted: 07/21/2017] [Indexed: 12/13/2022] Open
Abstract
Candida albicans is a major fungal pathogen causing life-threatening diseases in immuno-compromised patients. The efficacy of current drugs to combat C. albicans infections is limited, as these infections have a 40–60% mortality rate. There is a real need for novel therapeutic approaches, but such advances require a detailed knowledge of C. albicans and its in vivo pathogenesis. Additionally, any novel antifungal drugs against C. albicans infections will need to be tested for their in vivo efficacy over time. Fungal pathogenesis and drug-mediated resolution studies can both be evaluated using non-invasive in vivo imaging technologies. In the work presented here, we used a codon-optimized firefly luciferase reporter system for detecting C. albicans in mice. We adapted the firefly luciferase in order to improve its maximum emission intensity in the red light range (600–700 nm) as well as to improve its thermostability in mice. All non-invasive in vivo imaging of experimental animals was performed with a multimodal imaging system able to detect luminescent reporters and capture both reflectance and X-ray images. The modified firefly luciferase expressed in C. albicans (Mut2) was found to significantly increase the sensitivity of bioluminescence imaging (BLI) in systemic infections as compared to unmodified luciferase (Mut0). The same modified bioluminescence reporter system was used in an oropharyngeal candidiasis model. In both animal models, fungal loads could be correlated to the intensity of emitted light. Antifungal treatment efficacies were also evaluated on the basis of BLI signal intensity. In conclusion, BLI with a red-shifted firefly luciferase was found to be a powerful tool for testing the fate of C. albicans in various mice infection models.
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Affiliation(s)
- Stephane Dorsaz
- Institute of Microbiology, University of LausanneLausanne, Switzerland
| | - Alix T Coste
- Institute of Microbiology, University of LausanneLausanne, Switzerland
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Mezzanotte L, van 't Root M, Karatas H, Goun EA, Löwik CWGM. In Vivo Molecular Bioluminescence Imaging: New Tools and Applications. Trends Biotechnol 2017; 35:640-652. [PMID: 28501458 DOI: 10.1016/j.tibtech.2017.03.012] [Citation(s) in RCA: 199] [Impact Index Per Article: 28.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2016] [Revised: 03/07/2017] [Accepted: 03/27/2017] [Indexed: 12/19/2022]
Abstract
in vivo bioluminescence imaging (BLi) is an optical molecular imaging technique used to visualize molecular and cellular processes in health and diseases and to follow the fate of cells with high sensitivity using luciferase-based gene reporters. The high sensitivity of this technique arises from efficient photon production, followed by the reaction between luciferase enzymes and luciferin substrates. Novel discoveries and developments of luciferase reporters, substrates, and gene-editing techniques, and emerging fields of applications, promise a new era of deeper and more sensitive molecular imaging.
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Affiliation(s)
- Laura Mezzanotte
- Optical Molecular imaging, Department of Radiology, Erasmus MC, Rotterdam, The Netherlands.
| | - Moniek van 't Root
- Optical Molecular imaging, Department of Radiology, Erasmus MC, Rotterdam, The Netherlands
| | - Hacer Karatas
- Laboratory of Bioorganic Chemistry and Molecular Imaging, Institute of Chemical Sciences and Engineering (ISIC), Swiss Federal Institute of Technology Lausanne (EPFL), 1015 Lausanne, Switzerland
| | - Elena A Goun
- Laboratory of Bioorganic Chemistry and Molecular Imaging, Institute of Chemical Sciences and Engineering (ISIC), Swiss Federal Institute of Technology Lausanne (EPFL), 1015 Lausanne, Switzerland
| | - Clemens W G M Löwik
- Optical Molecular imaging, Department of Radiology, Erasmus MC, Rotterdam, The Netherlands
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Assessment and Optimizations of Candida albicans In Vitro Biofilm Assays. Antimicrob Agents Chemother 2017; 61:AAC.02749-16. [PMID: 28289028 DOI: 10.1128/aac.02749-16] [Citation(s) in RCA: 45] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2016] [Accepted: 03/03/2017] [Indexed: 01/07/2023] Open
Abstract
Candida albicans biofilms have a significant medical impact due to their rapid growth on implanted medical devices, their resistance to antifungal drugs, and their ability to seed disseminated infections. Biofilm assays performed in vitro allow for rapid, high-throughput screening of gene deletion libraries or antifungal compounds and typically serve as precursors to in vivo studies. Here, we compile and discuss the protocols for several recently published C. albicansin vitro biofilm assays. We also describe improved versions of these protocols as well as novel in vitro assays. Finally, we consider some of the advantages and disadvantages of these different types of assays.
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29
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Herwig L, Rice AJ, Bedbrook CN, Zhang RK, Lignell A, Cahn JKB, Renata H, Dodani SC, Cho I, Cai L, Gradinaru V, Arnold FH. Directed Evolution of a Bright Near-Infrared Fluorescent Rhodopsin Using a Synthetic Chromophore. Cell Chem Biol 2017; 24:415-425. [PMID: 28262559 DOI: 10.1016/j.chembiol.2017.02.008] [Citation(s) in RCA: 51] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2016] [Revised: 11/28/2016] [Accepted: 02/01/2017] [Indexed: 12/16/2022]
Abstract
By engineering a microbial rhodopsin, Archaerhodopsin-3 (Arch), to bind a synthetic chromophore, merocyanine retinal, in place of the natural chromophore all-trans-retinal (ATR), we generated a protein with exceptionally bright and unprecedentedly red-shifted near-infrared (NIR) fluorescence. We show that chromophore substitution generates a fluorescent Arch complex with a 200-nm bathochromic excitation shift relative to ATR-bound wild-type Arch and an emission maximum at 772 nm. Directed evolution of this complex produced variants with pH-sensitive NIR fluorescence and molecular brightness 8.5-fold greater than the brightest ATR-bound Arch variant. The resulting proteins are well suited to bacterial imaging; expression and stability have not been optimized for mammalian cell imaging. By targeting both the protein and its chromophore, we overcome inherent challenges associated with engineering bright NIR fluorescence into Archaerhodopsin. This work demonstrates an efficient strategy for engineering non-natural, tailored properties into microbial opsins, properties relevant for imaging and interrogating biological systems.
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Affiliation(s)
- Lukas Herwig
- Division of Chemistry and Chemical Engineering, California Institute of Technology, 1200 East California Boulevard, Pasadena, CA 91125, USA
| | - Austin J Rice
- Division of Chemistry and Chemical Engineering, California Institute of Technology, 1200 East California Boulevard, Pasadena, CA 91125, USA
| | - Claire N Bedbrook
- Division of Chemistry and Chemical Engineering, California Institute of Technology, 1200 East California Boulevard, Pasadena, CA 91125, USA; Division of Biology and Biological Engineering, California Institute of Technology, 1200 East California Boulevard, Pasadena, CA 91125, USA
| | - Ruijie K Zhang
- Division of Chemistry and Chemical Engineering, California Institute of Technology, 1200 East California Boulevard, Pasadena, CA 91125, USA
| | - Antti Lignell
- Division of Chemistry and Chemical Engineering, California Institute of Technology, 1200 East California Boulevard, Pasadena, CA 91125, USA
| | - Jackson K B Cahn
- Division of Chemistry and Chemical Engineering, California Institute of Technology, 1200 East California Boulevard, Pasadena, CA 91125, USA
| | - Hans Renata
- Division of Chemistry and Chemical Engineering, California Institute of Technology, 1200 East California Boulevard, Pasadena, CA 91125, USA
| | - Sheel C Dodani
- Division of Chemistry and Chemical Engineering, California Institute of Technology, 1200 East California Boulevard, Pasadena, CA 91125, USA
| | - Inha Cho
- Division of Chemistry and Chemical Engineering, California Institute of Technology, 1200 East California Boulevard, Pasadena, CA 91125, USA
| | - Long Cai
- Division of Chemistry and Chemical Engineering, California Institute of Technology, 1200 East California Boulevard, Pasadena, CA 91125, USA
| | - Viviana Gradinaru
- Division of Biology and Biological Engineering, California Institute of Technology, 1200 East California Boulevard, Pasadena, CA 91125, USA
| | - Frances H Arnold
- Division of Chemistry and Chemical Engineering, California Institute of Technology, 1200 East California Boulevard, Pasadena, CA 91125, USA; Division of Biology and Biological Engineering, California Institute of Technology, 1200 East California Boulevard, Pasadena, CA 91125, USA.
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Click beetle luciferases as dual reporters of gene expression in Candida albicans. Microbiology (Reading) 2016; 162:1310-1320. [DOI: 10.1099/mic.0.000329] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
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Abstract
In humans, microbial cells (including bacteria, archaea, and fungi) greatly outnumber host cells. Candida albicans is the most prevalent fungal species of the human microbiota; this species asymptomatically colonizes many areas of the body, particularly the gastrointestinal and genitourinary tracts of healthy individuals. Alterations in host immunity, stress, resident microbiota, and other factors can lead to C. albicans overgrowth, causing a wide range of infections, from superficial mucosal to hematogenously disseminated candidiasis. To date, most studies of C. albicans have been carried out in suspension cultures; however, the medical impact of C. albicans (like that of many other microorganisms) depends on its ability to thrive as a biofilm, a closely packed community of cells. Biofilms are notorious for forming on implanted medical devices, including catheters, pacemakers, dentures, and prosthetic joints, which provide a surface and sanctuary for biofilm growth. C. albicans biofilms are intrinsically resistant to conventional antifungal therapeutics, the host immune system, and other environmental perturbations, making biofilm-based infections a significant clinical challenge. Here, we review our current knowledge of biofilms formed by C. albicans and closely related fungal species.
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Affiliation(s)
- Clarissa J Nobile
- Department of Molecular and Cell Biology, School of Natural Sciences, University of California, Merced, California 95343;
| | - Alexander D Johnson
- Department of Microbiology and Immunology, University of California, San Francisco, California 94143;
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Seleem D, Benso B, Noguti J, Pardi V, Murata RM. In Vitro and In Vivo Antifungal Activity of Lichochalcone-A against Candida albicans Biofilms. PLoS One 2016; 11:e0157188. [PMID: 27284694 PMCID: PMC4902220 DOI: 10.1371/journal.pone.0157188] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2016] [Accepted: 05/25/2016] [Indexed: 11/18/2022] Open
Abstract
Oral candidiasis (OC) is an opportunistic fungal infection with high prevalence among immunocompromised patients. Candida albicans is the most common fungal pathogen responsible for OC, often manifested in denture stomatitis and oral thrush. Virulence factors, such as biofilms formation and secretion of proteolytic enzymes, are key components in the pathogenicity of C. albicans. Given the limited number of available antifungal therapies and the increase in antifungal resistance, demand the search for new safe and effective antifungal treatments. Lichochalcone-A is a polyphenol natural compound, known for its broad protective activities, as an antimicrobial agent. In this study, we investigated the antifungal activity of lichochalcone-A against C. albicans biofilms both in vitro and in vivo. Lichochalcone-A (625 μM; equivalent to 10x MIC) significantly reduced C. albicans (MYA 2876) biofilm growth compared to the vehicle control group (1% ethanol), as indicated by the reduction in the colony formation unit (CFU)/ml/g of biofilm dry weight. Furthermore, proteolytic enzymatic activities of proteinases and phospholipases, secreted by C. albicans were significantly decreased in the lichochalcone-A treated biofilms. In vivo model utilized longitudinal imaging of OC fungal load using a bioluminescent-engineered C. albicans (SKCa23-ActgLUC) and coelenterazine substrate. Mice treated with lichochalcone-A topical treatments exhibited a significant reduction in total photon flux over 4 and 5 days post-infection. Similarly, ex vivo analysis of tongue samples, showed a significant decrease in CFU/ml/mg in tongue tissue sample of lichochalcone-A treated group, which suggest the potential of lichochalcone-A as a novel antifungal agent for future clinical use.
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Affiliation(s)
- Dalia Seleem
- Herman Ostrow School of Dentistry, Division of Periodontology Diagnostic Sciences, Dental Hygiene and Biomedical Sciences, University of Southern California, Los Angeles, CA, United States of America
| | - Bruna Benso
- School of Dentistry, Faculty of Medicine, Universidad Austral de Chile, Campus Isla Teja, Valdivia, Chile
| | - Juliana Noguti
- Herman Ostrow School of Dentistry, Division of Periodontology Diagnostic Sciences, Dental Hygiene and Biomedical Sciences, University of Southern California, Los Angeles, CA, United States of America
| | - Vanessa Pardi
- Herman Ostrow School of Dentistry, Division of Periodontology Diagnostic Sciences, Dental Hygiene and Biomedical Sciences, University of Southern California, Los Angeles, CA, United States of America
| | - Ramiro Mendonça Murata
- Herman Ostrow School of Dentistry, Division of Periodontology Diagnostic Sciences, Dental Hygiene and Biomedical Sciences, University of Southern California, Los Angeles, CA, United States of America
- * E-mail:
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Longitudinal, in vivo assessment of invasive pulmonary aspergillosis in mice by computed tomography and magnetic resonance imaging. J Transl Med 2016; 96:692-704. [PMID: 27019389 DOI: 10.1038/labinvest.2016.45] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2015] [Revised: 02/09/2016] [Accepted: 02/23/2016] [Indexed: 11/09/2022] Open
Abstract
Invasive aspergillosis is an emerging threat to public health due to the increasing use of immune suppressive drugs and the emergence of resistance against antifungal drugs. To deal with this threat, research on experimental disease models provides insight into the pathogenesis of infections caused by susceptible and resistant Aspergillus strains and by assessing their response to antifungal drugs. However, standard techniques used to evaluate infection in a preclinical setting are severely limited by their invasive character, thereby precluding evaluation of disease extent and therapy effects in the same animal. To enable non-invasive, longitudinal monitoring of invasive pulmonary aspergillosis in mice, we optimized computed tomography (CT) and magnetic resonance imaging (MRI) techniques for daily follow-up of neutropenic BALB/c mice intranasally infected with A. fumigatus spores. Based on the images, lung parameters (signal intensity, lung tissue volume and total lung volume) were quantified to obtain objective information on disease onset, progression and extent for each animal individually. Fungal lung lesions present in infected animals were successfully visualized and quantified by both CT and MRI. By using an advanced MR pulse sequence with ultrashort echo times, pathological changes within the infected lung became visually and quantitatively detectable at earlier disease stages, thereby providing valuable information on disease onset and progression with high sensitivity. In conclusion, these non-invasive imaging techniques prove to be valuable tools for the longitudinal evaluation of dynamic disease-related changes and differences in disease severity in individual animals that might be readily applied for rapid and cost-efficient drug screening in preclinical models in vivo.
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Chauhan A, Ghigo JM, Beloin C. Study of in vivo catheter biofilm infections using pediatric central venous catheter implanted in rat. Nat Protoc 2016; 11:525-41. [DOI: 10.1038/nprot.2016.033] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
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Gulati M, Nobile CJ. Candida albicans biofilms: development, regulation, and molecular mechanisms. Microbes Infect 2016; 18:310-21. [PMID: 26806384 DOI: 10.1016/j.micinf.2016.01.002] [Citation(s) in RCA: 372] [Impact Index Per Article: 46.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2015] [Revised: 01/15/2016] [Accepted: 01/15/2016] [Indexed: 01/22/2023]
Abstract
A major virulence attribute of Candida albicans is its ability to form biofilms, densely packed communities of cells adhered to a surface. These biofilms are intrinsically resistant to conventional antifungal therapeutics, the host immune system, and other environmental factors, making biofilm-associated infections a significant clinical challenge. Here, we review current knowledge on the development, regulation, and molecular mechanisms of C. albicans biofilms.
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Affiliation(s)
- Megha Gulati
- Department of Molecular and Cell Biology, School of Natural Sciences, University of California, Merced, Merced, CA, USA
| | - Clarissa J Nobile
- Department of Molecular and Cell Biology, School of Natural Sciences, University of California, Merced, Merced, CA, USA.
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Abstract
The label-free detection of microbial cells attached to a surface is an active field of research. The field is driven by the need to understand and control the growth of biofilms in a number of applications, including basic research in natural environments, industrial facilities, and clinical devices, to name a few. Despite significant progress in the ability to monitor the growth of biofilms and related living cells, the sensitivity and selectivity of such sensors are still a challenge. We believe that among the many different technologies available for monitoring biofilm growth, optical techniques are the most promising, as they afford direct imaging and offer high sensitivity and specificity. Furthermore, as each technique offers different insights into the biofilm growth mechanism, our analysis allows us to provide an overview of the biological processes at play. In addition, we use a set of key parameters to compare state-of-the-art techniques in the field, including a critical assessment of each method, to identify the most promising types of sensors. We highlight the challenges that need to be overcome to improve the characteristics of current biofilm sensor technologies and indicate where further developments are required. In addition, we provide guidelines for selecting a suitable sensor for detecting microbial cells on a surface.
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Krappmann S. Lightning up the worm: How to probe fungal virulence in an alternative mini-host by bioluminescence. Virulence 2015; 6:727-9. [PMID: 26537579 PMCID: PMC4826133 DOI: 10.1080/21505594.2015.1103428] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022] Open
Affiliation(s)
- Sven Krappmann
- a Mikrobiologisches Institut - Klinische Mikrobiologie; Immunologie und Hygiene; Universitätsklinikum Erlangen; Friedrich-Alexander-Universität Erlangen-Nürnberg ; Erlangen , Germany.,b Medical Immunology Campus Erlangen; Friedrich-Alexander University Erlangen-Nürnberg ; Erlangen , Germany
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Kucharíková S, Vande Velde G, Himmelreich U, Van Dijck P. Candida albicans biofilm development on medically-relevant foreign bodies in a mouse subcutaneous model followed by bioluminescence imaging. J Vis Exp 2015:52239. [PMID: 25651138 DOI: 10.3791/52239] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022] Open
Abstract
Candida albicans biofilm development on biotic and/or abiotic surfaces represents a specific threat for hospitalized patients. So far, C. albicans biofilms have been studied predominantly in vitro but there is a crucial need for better understanding of this dynamic process under in vivo conditions. We developed an in vivo subcutaneous rat model to study C. albicans biofilm formation. In our model, multiple (up to 9) Candida-infected devices are implanted to the back part of the animal. This gives us a major advantage over the central venous catheter model system as it allows us to study several independent biofilms in one animal. Recently, we adapted this model to study C. albicans biofilm development in BALB/c mice. In this model, mature C. albicans biofilms develop within 48 hr and demonstrate the typical three-dimensional biofilm architecture. The quantification of fungal biofilm is traditionally analyzed post mortem and requires host sacrifice. Because this requires the use of many animals to perform kinetic studies, we applied non-invasive bioluminescence imaging (BLI) to longitudinally follow up in vivo mature C. albicans biofilms developing in our subcutaneous model. C. albicans cells were engineered to express the Gaussia princeps luciferase gene (gLuc) attached to the cell wall. The bioluminescence signal is produced by the luciferase that converts the added substrate coelenterazine into light that can be measured. The BLI signal resembled cell counts obtained from explanted catheters. Non-invasive imaging for quantifying in vivo biofilm formation provides immediate applications for the screening and validation of antifungal drugs under in vivo conditions, as well as for studies based on host-pathogen interactions, hereby contributing to a better understanding of the pathogenesis of catheter-associated infections.
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Affiliation(s)
- Soňa Kucharíková
- Department of Molecular Microbiology, Laboratory of Molecular Cell Biology, Institute of Botany and Microbiology, VIB, KU Leuven
| | | | - Uwe Himmelreich
- Biomedical MRI Unit/ MoSAIC, Department of Imaging & Pathology, KU Leuven
| | - Patrick Van Dijck
- Department of Molecular Microbiology, Laboratory of Molecular Cell Biology, Institute of Botany and Microbiology, VIB, KU Leuven;
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Kucharíková S, Neirinck B, Sharma N, Vleugels J, Lagrou K, Van Dijck P. In vivo Candida glabrata biofilm development on foreign bodies in a rat subcutaneous model. J Antimicrob Chemother 2014; 70:846-56. [PMID: 25406296 DOI: 10.1093/jac/dku447] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
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.
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Affiliation(s)
- Soňa Kucharíková
- 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
| | - Bram Neirinck
- Department of Materials Engineering, KU Leuven, Kasteelpark Arenberg 44, B-3001 Heverlee-Leuven, Belgium
| | - Nidhi Sharma
- 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
| | - Jef Vleugels
- Department of Materials Engineering, KU Leuven, Kasteelpark Arenberg 44, B-3001 Heverlee-Leuven, Belgium
| | - Katrien Lagrou
- Department of Microbiology and Immunology, KU Leuven, Leuven, Belgium
| | - Patrick Van Dijck
- 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
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Jacobsen ID, Lüttich A, Kurzai O, Hube B, Brock M. In vivo imaging of disseminated murine Candida albicans infection reveals unexpected host sites of fungal persistence during antifungal therapy. J Antimicrob Chemother 2014; 69:2785-96. [PMID: 24951534 DOI: 10.1093/jac/dku198] [Citation(s) in RCA: 54] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
OBJECTIVES Candida albicans is an important fungal pathogen that can cause life-threatening disseminated infections. To determine the efficacy of therapy in murine models, a determination of renal fungal burden as cfu is commonly used. However, this approach provides only a snapshot of the current situation in an individual animal and cryptic sites of infection may easily be missed. Thus, we aimed to develop real-time non-invasive imaging to monitor infection in vivo. METHODS Bioluminescent C. albicans reporter strains were developed based on a bioinformatical approach for codon optimization. The reporter strains were analysed in vitro and in vivo in the murine model of systemic candidiasis. RESULTS Reporter strains allowed the in vivo monitoring of infection and a determination of fungal burden, with a high correlation between bioluminescence and cfu count. We confirmed the kidney as the main target organ but additionally observed the translocation of C. albicans to the urinary bladder. The treatment of infected mice with caspofungin and fluconazole significantly improved the clinical outcome and clearance of C. albicans from the kidneys; however, unexpectedly, viable fungal cells persisted in the gall bladder. Fungi were secreted with bile and detected in the faeces, implicating the gall bladder as a reservoir for colonization by C. albicans after antifungal therapy. Bile extracts significantly decreased the susceptibility of C. albicans to various antifungals in vitro, thereby probably contributing to its persistence. CONCLUSIONS Using in vivo imaging, we identified cryptic sites of infection and persistence of C. albicans in the gall bladder during otherwise effective antifungal treatment. Bile appears to directly interfere with antifungal activity.
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Affiliation(s)
- Ilse D Jacobsen
- Microbial Immunology, Hans Knoell Institute, Leibniz Institute for Natural Product Research and Infection Biology, Beutenbergstrasse 11a, 07745 Jena, Germany
| | - Anja Lüttich
- Microbial Pathogenicity Mechanisms, Hans Knoell Institute, Leibniz Institute for Natural Product Research and Infection Biology, Beutenbergstrasse 11a, 07745 Jena, Germany
| | - Oliver Kurzai
- Septomics Research Center, Friedrich-Schiller University Jena and Leibniz Institute for Natural Product Research and Infection Biology, Albert-Einstein Strasse 10, 07745 Jena, Germany
| | - Bernhard Hube
- Microbial Pathogenicity Mechanisms, Hans Knoell Institute, Leibniz Institute for Natural Product Research and Infection Biology, Beutenbergstrasse 11a, 07745 Jena, Germany Friedrich Schiller University, Jena, Germany Center for Sepsis Control and Care, Universitätsklinikum Jena, Jena, Germany
| | - Matthias Brock
- Friedrich Schiller University, Jena, Germany Microbial Biochemistry and Physiology, Hans Knoell Institute, Leibniz Institute for Natural Product Research and Infection Biology, Beutenbergstrasse 11a, 07745 Jena, Germany
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Demuyser L, Jabra-Rizk MA, Van Dijck P. Microbial cell surface proteins and secreted metabolites involved in multispecies biofilms. Pathog Dis 2014; 70:219-30. [PMID: 24376219 DOI: 10.1111/2049-632x.12123] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2013] [Revised: 12/16/2013] [Accepted: 12/16/2013] [Indexed: 12/15/2022] Open
Abstract
A considerable number of infectious diseases involve multiple microbial species coexisting and interacting in a host. Only recently however the impact of these polymicrobial diseases has been appreciated and investigated. Often, the causative microbial species are embedded in an extracellular matrix forming biofilms, a form of existence that offers protection against chemotherapeutic agents and host immune defenses. Therefore, recent efforts have focused on developing novel therapeutic strategies targeting biofilm-associated polymicrobial infections, a task that has proved to be challenging. One promising approach to inhibit the development of such complex infections is to impede the interactions between the microbial species via inhibition of adhesion. To that end, studies have focused on identifying specific cell wall adhesins and receptors involved in the interactions between the various bacterial species and the most pathogenic human fungal species Candida albicans. This review highlights the important findings from these studies and describes the available tools and techniques that have provided insights into the role of secreted molecules orchestrating microbial interactions in biofilms. Specifically, we focus on the interactions that take place in oral biofilms and the implications of these interactions on oral health and therapeutic strategies.
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Affiliation(s)
- Liesbeth Demuyser
- VIB Department of Molecular Microbiology, KU Leuven, Leuven, Belgium; Laboratory of Molecular Cell Biology, KU Leuven, Leuven, Belgium
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