101
|
Galleria mellonella Larvae as an Infection Model for Penicillium marneffei. Mycopathologia 2015; 180:159-64. [PMID: 26003722 DOI: 10.1007/s11046-015-9897-y] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2014] [Accepted: 05/02/2015] [Indexed: 10/23/2022]
Abstract
Penicillium marneffei, the only known dimorphic and pathogenic species in the genus of Penicillium, is responsible for severe to deadly infection in immunocompromised patients. In this study, P. marneffei was able to infect the greater wax moth Galleria mellonella. The increasing inoculum doses of P. marneffei cells resulted in greater larval mortality, and the larval mortality rate also depended on the incubation temperature after P. marneffei infection and different P. marneffei strains. Moreover, the phagocytosis of hemocytes to P. marneffei was investigated, and it showed that the phagocytosis was increasing during the infection. These results demonstrated that G. mellonella can be effectively used to facilitate the in vivo study of P. marneffei infection and hemocytes are the key component of the larvae's immune defenses.
Collapse
|
102
|
Amorim-Vaz S, Delarze E, Ischer F, Sanglard D, Coste AT. Examining the virulence of Candida albicans transcription factor mutants using Galleria mellonella and mouse infection models. Front Microbiol 2015; 6:367. [PMID: 25999923 PMCID: PMC4419840 DOI: 10.3389/fmicb.2015.00367] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2015] [Accepted: 04/10/2015] [Indexed: 01/08/2023] Open
Abstract
The aim of the present study was to identify Candida albicans transcription factors (TFs) involved in virulence. Although mice are considered the gold-standard model to study fungal virulence, mini-host infection models have been increasingly used. Here, barcoded TF mutants were first screened in mice by pools of strains and fungal burdens (FBs) quantified in kidneys. Mutants of unannotated genes which generated a kidney FB significantly different from that of wild-type were selected and individually examined in Galleria mellonella. In addition, mutants that could not be detected in mice were also tested in G. mellonella. Only 25% of these mutants displayed matching phenotypes in both hosts, highlighting a significant discrepancy between the two models. To address the basis of this difference (pool or host effects), a set of 19 mutants tested in G. mellonella were also injected individually into mice. Matching FB phenotypes were observed in 50% of the cases, highlighting the bias due to host effects. In contrast, 33.4% concordance was observed between pool and single strain infections in mice, thereby highlighting the bias introduced by the "pool effect." After filtering the results obtained from the two infection models, mutants for MBF1 and ZCF6 were selected. Independent marker-free mutants were subsequently tested in both hosts to validate previous results. The MBF1 mutant showed impaired infection in both models, while the ZCF6 mutant was only significant in mice infections. The two mutants showed no obvious in vitro phenotypes compared with the wild-type, indicating that these genes might be specifically involved in in vivo adapt.
Collapse
Affiliation(s)
- Sara Amorim-Vaz
- Institute of Microbiology, University of Lausanne and University Hospital of Lausanne Lausanne, Switzerland
| | - Eric Delarze
- Institute of Microbiology, University of Lausanne and University Hospital of Lausanne Lausanne, Switzerland
| | - Françoise Ischer
- Institute of Microbiology, University of Lausanne and University Hospital of Lausanne Lausanne, Switzerland
| | - Dominique Sanglard
- Institute of Microbiology, University of Lausanne and University Hospital of Lausanne Lausanne, Switzerland
| | - Alix T Coste
- Institute of Microbiology, University of Lausanne and University Hospital of Lausanne Lausanne, Switzerland
| |
Collapse
|
103
|
Desbois AP, McMillan S. Paving the way to acceptance of Galleria mellonella as a new model insect. Virulence 2015; 6:410-1. [PMID: 25906067 DOI: 10.1080/21505594.2015.1036218] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022] Open
Affiliation(s)
- Andrew P Desbois
- a Marine Biotechnology Research Group; Institute of Aquaculture; School of Natural Sciences; University of Stirling ; Stirling , UK
| | | |
Collapse
|
104
|
Kaur J, Duan SY, Vaas LAI, Penesyan A, Meyer W, Paulsen IT, Nevalainen H. Phenotypic profiling of Scedosporium aurantiacum, an opportunistic pathogen colonizing human lungs. PLoS One 2015; 10:e0122354. [PMID: 25811884 PMCID: PMC4374879 DOI: 10.1371/journal.pone.0122354] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2014] [Accepted: 02/13/2015] [Indexed: 12/25/2022] Open
Abstract
Genotyping studies of Australian Scedosporium isolates have revealed the strong prevalence of a recently described species: Scedosporium aurantiacum. In addition to occurring in the environment, this fungus is also known to colonise the respiratory tracts of cystic fibrosis (CF) patients. A high throughput Phenotype Microarray (PM) analysis using 94 assorted substrates (sugars, amino acids, hexose-acids and carboxylic acids) was carried out for four isolates exhibiting different levels of virulence, determined using a Galleria mellonella infection model. A significant difference was observed in the substrate utilisation patterns of strains displaying differential virulence. For example, certain sugars such as sucrose (saccharose) were utilised only by low virulence strains whereas some sugar derivatives such as D-turanose promoted respiration only in the more virulent strains. Strains with a higher level of virulence also displayed flexibility and metabolic adaptability at two different temperature conditions tested (28 and 37°C). Phenotype microarray data were integrated with the whole-genome sequence data of S. aurantiacum to reconstruct a pathway map for the metabolism of selected substrates to further elucidate differences between the strains.
Collapse
Affiliation(s)
- Jashanpreet Kaur
- Department of Chemistry and Biomolecular Sciences, Macquarie University, Sydney, Australia
- Biomolecular Frontiers Research Centre, Macquarie University, Sydney, Australia
| | - Shu Yao Duan
- Molecular Mycology Research Laboratory, Centre for Infectious Diseases and Microbiology, Marie Bashir Institute for Infectious Diseases and Biosecurity, Sydney Medical School—Westmead Hospital, The University of Sydney, Westmead Millennium Institute, Sydney, Australia
| | - Lea A. I. Vaas
- Molecular Mycology Research Laboratory, Centre for Infectious Diseases and Microbiology, Marie Bashir Institute for Infectious Diseases and Biosecurity, Sydney Medical School—Westmead Hospital, The University of Sydney, Westmead Millennium Institute, Sydney, Australia
- Bioinformatics Group, Centralbureau voor Schimmelculturen—Fungal Biodiversity Centre, Utrecht, The Netherlands
| | - Anahit Penesyan
- Department of Chemistry and Biomolecular Sciences, Macquarie University, Sydney, Australia
- Biomolecular Frontiers Research Centre, Macquarie University, Sydney, Australia
| | - Wieland Meyer
- Molecular Mycology Research Laboratory, Centre for Infectious Diseases and Microbiology, Marie Bashir Institute for Infectious Diseases and Biosecurity, Sydney Medical School—Westmead Hospital, The University of Sydney, Westmead Millennium Institute, Sydney, Australia
| | - Ian T. Paulsen
- Department of Chemistry and Biomolecular Sciences, Macquarie University, Sydney, Australia
- Biomolecular Frontiers Research Centre, Macquarie University, Sydney, Australia
| | - Helena Nevalainen
- Department of Chemistry and Biomolecular Sciences, Macquarie University, Sydney, Australia
- Biomolecular Frontiers Research Centre, Macquarie University, Sydney, Australia
- * E-mail:
| |
Collapse
|
105
|
Brunke S, Quintin J, Kasper L, Jacobsen ID, Richter ME, Hiller E, Schwarzmüller T, d'Enfert C, Kuchler K, Rupp S, Hube B, Ferrandon D. Of mice, flies--and men? Comparing fungal infection models for large-scale screening efforts. Dis Model Mech 2015; 8:473-86. [PMID: 25786415 PMCID: PMC4415897 DOI: 10.1242/dmm.019901] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2015] [Accepted: 03/17/2015] [Indexed: 12/14/2022] Open
Abstract
Studying infectious diseases requires suitable hosts for experimental in vivo infections. Recent years have seen the advent of many alternatives to murine infection models. However, the use of non-mammalian models is still controversial because it is often unclear how well findings from these systems predict virulence potential in humans or other mammals. Here, we compare the commonly used models, fruit fly and mouse (representing invertebrate and mammalian hosts), for their similarities and degree of correlation upon infection with a library of mutants of an important fungal pathogen, the yeast Candida glabrata. Using two indices, for fly survival time and for mouse fungal burden in specific organs, we show a good agreement between the models. We provide a suitable predictive model for estimating the virulence potential of C. glabrata mutants in the mouse from fly survival data. As examples, we found cell wall integrity mutants attenuated in flies, and mutants of a MAP kinase pathway had defective virulence in flies and reduced relative pathogen fitness in mice. In addition, mutants with strongly reduced in vitro growth generally, but not always, had reduced virulence in flies. Overall, we demonstrate that surveying Drosophila survival after infection is a suitable model to predict the outcome of murine infections, especially for severely attenuated C. glabrata mutants. Pre-screening of mutants in an invertebrate Drosophila model can, thus, provide a good estimate of the probability of finding a strain with reduced microbial burden in the mouse host. Summary: Can the fitness of deletion mutants in a murine model be predicted by their virulence in Drosophila melanogaster? For a fungal pathogen, the answer is, mostly, yes.
Collapse
Affiliation(s)
- Sascha Brunke
- Integrated Research and Treatment Center, Center for Sepsis Control and Care (CSCC), University Hospital, 07747 Jena, Germany Department of Microbial Pathogenicity Mechanisms, Hans Knöll Institute, 07745 Jena, Germany
| | - Jessica Quintin
- Equipe Fondation Recherche Médicale, Unité Propre de Recherche 9022 du Centre National de la Recherche Scientifique (CNRS), Institut de Biologie Moléculaire et Cellulaire (IBMC), Université de Strasbourg, 67084 Strasbourg, France
| | - Lydia Kasper
- Department of Microbial Pathogenicity Mechanisms, Hans Knöll Institute, 07745 Jena, Germany
| | - Ilse D Jacobsen
- Research Group Microbial Immunology, Hans Knöll Institute, 07745 Jena, Germany Friedrich Schiller University, 07743 Jena, Germany
| | - Martin E Richter
- Integrated Research and Treatment Center, Center for Sepsis Control and Care (CSCC), University Hospital, 07747 Jena, Germany Institute for Clinical Chemistry and Laboratory Medicine, Jena University Hospital, 07747 Jena, Germany
| | - Ekkehard Hiller
- Department of Molecular Biotechnology, Fraunhofer Institute for Interfacial Engineering and Biotechnology, 70569 Stuttgart, Germany
| | - Tobias Schwarzmüller
- Department of Medical Biochemistry, Max F. Perutz Laboratories, Medical University Vienna, 1030 Vienna, Austria
| | - Christophe d'Enfert
- Institut Pasteur, Unité Biologie et Pathogénicité Fongiques, Département Génomes et Génétique, 75015 Paris, France INRA, USC2019, 75015 Paris, France
| | - Karl Kuchler
- Department of Medical Biochemistry, Max F. Perutz Laboratories, Medical University Vienna, 1030 Vienna, Austria
| | - Steffen Rupp
- Department of Molecular Biotechnology, Fraunhofer Institute for Interfacial Engineering and Biotechnology, 70569 Stuttgart, Germany
| | - Bernhard Hube
- Integrated Research and Treatment Center, Center for Sepsis Control and Care (CSCC), University Hospital, 07747 Jena, Germany Department of Microbial Pathogenicity Mechanisms, Hans Knöll Institute, 07745 Jena, Germany Friedrich Schiller University, 07743 Jena, Germany
| | - Dominique Ferrandon
- Equipe Fondation Recherche Médicale, Unité Propre de Recherche 9022 du Centre National de la Recherche Scientifique (CNRS), Institut de Biologie Moléculaire et Cellulaire (IBMC), Université de Strasbourg, 67084 Strasbourg, France
| |
Collapse
|
106
|
Browne N, Surlis C, Maher A, Gallagher C, Carolan JC, Clynes M, Kavanagh K. Prolonged pre-incubation increases the susceptibility of Galleria mellonella larvae to bacterial and fungal infection. Virulence 2015; 6:458-65. [PMID: 25785635 DOI: 10.1080/21505594.2015.1021540] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
Galleria mellonella larvae are widely used for assessing the virulence of microbial pathogens and for measuring the in vivo activity of antimicrobial agents and produce results comparable to those that can be obtained using mammals. The aim of the work described here was to ascertain the effect of pre-incubation at 15°C for 1, 3, 6 or 10 weeks on the susceptibility of larvae to infection with Candida albicans and Staphylococcus aureus. Larvae infected with C. albicans after 1 week pre-incubation at 15°C showed 73.3 ± 3.3% survival at 24 hours post-infection while those infected after 10 weeks pre-incubation showed 30 ± 3.3% survival (P < 0.01). Larvae infected with S. aureus after 1 week pre-incubation showed 65.5 ± 3.3% survival after 24 hours while those infected after 10 weeks pre-incubation showed 13.3 ± 3.3% (P < 0.001). Analysis of the haemocyte density in larvae pre-incubated for 3-10 weeks showed a reduction in haemocytes over time but a proportionate increase in the density of granular haemocytes in the population as determined by FACS analysis. Proteomic analysis revealed decreased abundance of proteins associated with metabolic pathways (e.g. malate dehydrogenase, fructose-1,6-bisphosphatase, glyceraldehyde-3-phosphate dehydrogenase) and prophenoloxidase. G. mellonella larvae are a useful in vivo model system but the duration of the pre-incubation stage significantly affects their susceptibility to microbial pathogens possibly as a result of altered metabolism.
Collapse
Affiliation(s)
- Niall Browne
- a Department of Biology; Maynooth University ; Maynooth , Kildare , Ireland
| | | | | | | | | | | | | |
Collapse
|
107
|
Trevijano-Contador N, Herrero-Fernández I, García-Barbazán I, Scorzoni L, Rueda C, Rossi SA, García-Rodas R, Zaragoza O. Cryptococcus neoformans induces antimicrobial responses and behaves as a facultative intracellular pathogen in the non mammalian model Galleria mellonella. Virulence 2015; 6:66-74. [PMID: 25531532 PMCID: PMC4603429 DOI: 10.4161/21505594.2014.986412] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2014] [Revised: 10/05/2014] [Accepted: 11/06/2014] [Indexed: 11/19/2022] Open
Abstract
Cryptococcus neoformans is an encapsulated opportunistic fungal pathogen that is found in multiple niches in the environment and that can cause fatal meningoencephalitis in susceptible patients, mainly HIV+ individuals. Cryptococcus also infects environmental hosts such as nematodes, insects and plants. In particular, C. neoformans can kill the lepidopteran Galleria mellonella, which offers a useful tool to study microbial virulence and drug efficacy. Galleria mellonella immunity relies on innate responses based on melanization, accumulation of antimicrobial peptides, and cellular responses as phagocytosis or multicellular encapsulation. In this work we have investigated the immune response of G. mellonella during cryptococcal infection. We found that G. mellonella infected with C. neoformans had a high lytic activity in their hemolymph. This response was temperature- and capsule-dependent. During interaction with phagocytic cells, C. neoformans behaved as an intracellular pathogen since it could replicate within hemocytes. Non-lytic events were also observed. In contrast to Candida species, C. neoformans did not induce melanization of G. mellonella after infection. Finally, passage of C. neoformans through G. mellonella resulted in changes in capsule structure as it has been also reported during infection in mammals. Our results highlight that G. mellonella is an optimal model to investigate innate immune responses against C. neoformans.
Collapse
Affiliation(s)
- Nuria Trevijano-Contador
- Mycology Reference Laboratory; National Center for Microbiology; Instituto de Salud Carlos III; Carretera Majadahonda-Pozuelo, Km2; Majadahonda, 28220, Madrid, Spain
| | - Inés Herrero-Fernández
- Mycology Reference Laboratory; National Center for Microbiology; Instituto de Salud Carlos III; Carretera Majadahonda-Pozuelo, Km2; Majadahonda, 28220, Madrid, Spain
| | - Irene García-Barbazán
- Mycology Reference Laboratory; National Center for Microbiology; Instituto de Salud Carlos III; Carretera Majadahonda-Pozuelo, Km2; Majadahonda, 28220, Madrid, Spain
| | - Liliana Scorzoni
- Mycology Reference Laboratory; National Center for Microbiology; Instituto de Salud Carlos III; Carretera Majadahonda-Pozuelo, Km2; Majadahonda, 28220, Madrid, Spain
- Laboratório de Micologia Clínica; Faculdade de Ciências Farmacêuticas; R. Expedicionários do Brasil, 1621, CEP. 14801–902, Araraquara, São Paulo, Brazil
| | - Cristina Rueda
- Mycology Reference Laboratory; National Center for Microbiology; Instituto de Salud Carlos III; Carretera Majadahonda-Pozuelo, Km2; Majadahonda, 28220, Madrid, Spain
| | - Suélen Andreia Rossi
- Mycology Reference Laboratory; National Center for Microbiology; Instituto de Salud Carlos III; Carretera Majadahonda-Pozuelo, Km2; Majadahonda, 28220, Madrid, Spain
- Laboratório de Micologia Clínica; Faculdade de Ciências Farmacêuticas; R. Expedicionários do Brasil, 1621, CEP. 14801–902, Araraquara, São Paulo, Brazil
| | - Rocío García-Rodas
- Mycology Reference Laboratory; National Center for Microbiology; Instituto de Salud Carlos III; Carretera Majadahonda-Pozuelo, Km2; Majadahonda, 28220, Madrid, Spain
| | - Oscar Zaragoza
- Mycology Reference Laboratory; National Center for Microbiology; Instituto de Salud Carlos III; Carretera Majadahonda-Pozuelo, Km2; Majadahonda, 28220, Madrid, Spain
| |
Collapse
|
108
|
Suwunnakorn S, Cooper CR, Kummasook A, Pongpom M, Vanittanakom P, Vanittanakom N. Role of the rttA gene in morphogenesis, stress response, and virulence in the human pathogenic fungus Penicillium marneffei. Med Mycol 2014; 53:119-31. [DOI: 10.1093/mmy/myu063] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
|
109
|
Vargas G, Rocha JDB, Oliveira DL, Albuquerque PC, Frases S, Santos SS, Nosanchuk JD, Gomes AMO, Medeiros LCAS, Miranda K, Sobreira TJP, Nakayasu ES, Arigi EA, Casadevall A, Guimaraes AJ, Rodrigues ML, Freire-de-Lima CG, Almeida IC, Nimrichter L. Compositional and immunobiological analyses of extracellular vesicles released by Candida albicans. Cell Microbiol 2014; 17:389-407. [PMID: 25287304 DOI: 10.1111/cmi.12374] [Citation(s) in RCA: 198] [Impact Index Per Article: 19.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2013] [Revised: 09/08/2014] [Accepted: 09/22/2014] [Indexed: 12/14/2022]
Abstract
The release of extracellular vesicles (EV) by fungal organisms is considered an alternative transport mechanism to trans-cell wall passage of macromolecules. Previous studies have revealed the presence of EV in culture supernatants from fungal pathogens, such as Cryptococcus neoformans, Histoplasma capsulatum, Paracoccidioides brasiliensis, Sporothrix schenckii, Malassezia sympodialis and Candida albicans. Here we investigated the size, composition, kinetics of internalization by bone marrow-derived murine macrophages (MO) and dendritic cells (DC), and the immunomodulatory activity of C. albicans EV. We also evaluated the impact of EV on fungal virulence using the Galleria mellonella larvae model. By transmission electron microscopy and dynamic light scattering, we identified two populations ranging from 50 to 100 nm and 350 to 850 nm. Two predominant seroreactive proteins (27 kDa and 37 kDa) and a group of polydispersed mannoproteins were observed in EV by immunoblotting analysis. Proteomic analysis of C. albicans EV revealed proteins related to pathogenesis, cell organization, carbohydrate and lipid metabolism, response to stress, and several other functions. The major lipids detected by thin-layer chromatography were ergosterol, lanosterol and glucosylceramide. Short exposure of MO to EV resulted in internalization of these vesicles and production of nitric oxide, interleukin (IL)-12, transforming growth factor-beta (TGF-β) and IL-10. Similarly, EV-treated DC produced IL-12p40, IL-10 and tumour necrosis factor-alpha. In addition, EV treatment induced the up-regulation of CD86 and major histocompatibility complex class-II (MHC-II). Inoculation of G. mellonella larvae with EV followed by challenge with C. albicans reduced the number of recovered viable yeasts in comparison with infected larvae control. Taken together, our results demonstrate that C. albicans EV were immunologically active and could potentially interfere with the host responses in the setting of invasive candidiasis.
Collapse
Affiliation(s)
- Gabriele Vargas
- Instituto de Microbiologia Paulo de Góes, Universidade Federal do Rio de Janeiro (UFRJ), Rio de Janeiro, RJ, Brazil
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
110
|
Suwunnakorn S, Cooper CR, Kummasook A, Vanittanakom N. Role of the yakA gene in morphogenesis and stress response in Penicillium marneffei. Microbiology (Reading) 2014; 160:1929-1939. [DOI: 10.1099/mic.0.080689-0] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Penicillium marneffei is a thermally dimorphic fungus and a highly significant pathogen of immunocompromised individuals living in or having travelled in south-east Asia. At 25 °C, P. marneffei grows filamentously. Under the appropriate conditions, these filaments (hyphae) produce conidiophores bearing chains of conidia. Yet, when incubated at 37 °C, or upon infecting host tissue, P. marneffei grows as a yeast that divides by binary fission. Previously, an Agrobacterium-mediated transformation system was used to randomly mutagenize P. marneffei, resulting in the isolation of a mutant defective in normal patterns of morphogenesis and conidiogenesis. The interrupted gene was identified as yakA. In the current study, we demonstrate that the yakA mutant produced fewer conidia at 25 °C than the wild-type and a complemented strain. In addition, disruption of the yakA gene resulted in early conidial germination and perturbation of cell wall integrity. The yakA mutant exhibited abnormal chitin distribution while growing at 25 °C, but not at 37 °C. Interestingly, at both temperatures, the yakA mutant possessed increased chitin content, which was accompanied by amplified transcription of two chitin synthase genes, chsB and chsG. Moreover, the expression of yakA was induced during post-exponential-phase growth as well as by heat shock. Thus, yakA is required for normal patterns of development, cell wall integrity, chitin deposition, appropriate chs expression and heat stress response in P. marneffei.
Collapse
Affiliation(s)
- Sumanun Suwunnakorn
- Center for Applied Chemical Biology and Department of Biological Sciences, Youngstown State University, One University Plaza, Youngstown, OH 44555, USA
- Department of Microbiology, Faculty of Medicine, Chiang Mai University, Chiang Mai 50200, Thailand
| | - Chester R. Cooper
- Center for Applied Chemical Biology and Department of Biological Sciences, Youngstown State University, One University Plaza, Youngstown, OH 44555, USA
| | - Aksarakorn Kummasook
- Division of Clinical Microbiology, Department of Medical Technology, School of Allied Health Sciences, University of Phayao, Phayao 56000, Thailand
| | - Nongnuch Vanittanakom
- Department of Microbiology, Faculty of Medicine, Chiang Mai University, Chiang Mai 50200, Thailand
| |
Collapse
|
111
|
Alghoribi MF, Gibreel TM, Dodgson AR, Beatson SA, Upton M. Galleria mellonella infection model demonstrates high lethality of ST69 and ST127 uropathogenic E. coli. PLoS One 2014; 9:e101547. [PMID: 25061819 PMCID: PMC4111486 DOI: 10.1371/journal.pone.0101547] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2014] [Accepted: 06/09/2014] [Indexed: 01/09/2023] Open
Abstract
Galleria mellonella larvae are an alternative in vivo model for investigating bacterial pathogenicity. Here, we examined the pathogenicity of 71 isolates from five leading uropathogenic E. coli (UPEC) lineages using G. mellonella larvae. Larvae were challenged with a range of inoculum doses to determine the 50% lethal dose (LD50) and for analysis of survival outcome using Kaplan-Meier plots. Virulence was correlated with carriage of a panel of 29 virulence factors (VF). Larvae inoculated with ST69 and ST127 isolates (104 colony-forming units/larvae) showed significantly higher mortality rates than those infected with ST73, ST95 and ST131 isolates, killing 50% of the larvae within 24 hours. Interestingly, ST131 isolates were the least virulent. We observed that ST127 isolates are significantly associated with a higher VF-score than isolates of all other STs tested (P≤0.0001), including ST69 (P<0.02), but one ST127 isolate (strain EC18) was avirulent. Comparative genomic analyses with virulent ST127 strains revealed an IS1 mediated deletion in the O-antigen cluster in strain EC18, which is likely to explain the lack of virulence in the larvae infection model. Virulence in the larvae was not correlated with serotype or phylogenetic group. This study illustrates that G. mellonella are an excellent tool for investigation of the virulence of UPEC strains. The findings also support our suggestion that the incidence of ST127 strains should be monitored, as these isolates have not yet been widely reported, but they clearly have a pathogenic potential greater than that of more widely recognised clones, including ST73, ST95 or ST131.
Collapse
Affiliation(s)
- Majed F. Alghoribi
- Microbiology and Virology Unit, School of Medicine, University of Manchester, Manchester, United Kingdom
- King Abdullah International Medical Research Center, King Saud bin Abdulaziz University for Health Sciences, Riyadh, Saudi Arabia
| | - Tarek M. Gibreel
- Microbiology and Virology Unit, School of Medicine, University of Manchester, Manchester, United Kingdom
| | | | - Scott A. Beatson
- Australian Infectious Disease Centre, School of Chemistry & Molecular Biosciences, University of Queensland, Queensland, Australia
| | - Mathew Upton
- Microbiology and Virology Unit, School of Medicine, University of Manchester, Manchester, United Kingdom
- School of Biomedical and Healthcare Science, Plymouth University Peninsula Schools of Medicine and Dentistry, Plymouth, United Kingdom
- * E-mail:
| |
Collapse
|
112
|
Assessment of in vivo antimicrobial activity of the carbene silver(I) acetate derivative SBC3 using Galleria mellonella larvae. Biometals 2014; 27:745-52. [DOI: 10.1007/s10534-014-9766-z] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2014] [Accepted: 06/19/2014] [Indexed: 10/25/2022]
|
113
|
Sherry L, Rajendran R, Lappin DF, Borghi E, Perdoni F, Falleni M, Tosi D, Smith K, Williams C, Jones B, Nile CJ, Ramage G. Biofilms formed by Candida albicans bloodstream isolates display phenotypic and transcriptional heterogeneity that are associated with resistance and pathogenicity. BMC Microbiol 2014; 14:182. [PMID: 24996549 PMCID: PMC4105547 DOI: 10.1186/1471-2180-14-182] [Citation(s) in RCA: 106] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2014] [Accepted: 06/24/2014] [Indexed: 12/21/2022] Open
Abstract
BACKGROUND Candida albicans infections have become increasingly recognised as being biofilm related. Recent studies have shown that there is a relationship between biofilm formation and poor clinical outcomes in patients infected with biofilm proficient strains. Here we have investigated a panel of clinical isolates in an attempt to evaluate their phenotypic and transcriptional properties in an attempt to differentiate and define levels of biofilm formation. RESULTS Biofilm formation was shown to be heterogeneous; with isolates being defined as either high or low biofilm formers (LBF and HBF) based on different biomass quantification. These categories could also be differentiated using a cell surface hydrophobicity assay with 24 h biofilms. HBF isolates were more resistance to amphotericin B (AMB) treatment than LBF, but not voriconazole (VRZ). In a Galleria mellonella model of infection HBF mortality was significantly increased in comparison to LBF. Histological analysis of the HBF showed hyphal elements intertwined indicative of the biofilm phenotype. Transcriptional analysis of 23 genes implicated in biofilm formation showed no significant differential expression profiles between LBF and HBF, except for Cdr1 at 4 and 24 h. Cluster analysis showed similar patterns of expression for different functional classes of genes, though correlation analysis of the 4 h biofilms with overall biomass at 24 h showed that 7 genes were correlated with high levels of biofilm, including Als3, Eap1, Cph1, Sap5, Plb1, Cdr1 and Zap1. CONCLUSIONS Our findings show that biofilm formation is variable amongst C. albicans isolates, and categorising isolates depending on this can be used to predict how pathogenic the isolate will behave clinically. We have shown that looking at individual genes in less informative than looking at multiple genes when trying to categorise isolates at LBF or HBF. These findings are important when developing biofilm-specific diagnostics as these could be used to predict how best to treat patients infected with C. albicans. Further studies are required to evaluate this clinically.
Collapse
Affiliation(s)
| | | | | | | | | | | | | | | | | | | | | | - Gordon Ramage
- Infection and Immunity Research Group, Glasgow Dental School, School of Medicine, College of Medical, Veterinary and Life Sciences, University of Glasgow, 378 Sauchiehall Street, Glasgow G2 3JZ, UK.
| |
Collapse
|
114
|
Trevijano-Contador N, Zaragoza O. Expanding the use of alternative models to investigate novel aspects of immunity to microbial pathogens. Virulence 2014; 5:454-6. [PMID: 24717215 PMCID: PMC4063805 DOI: 10.4161/viru.28775] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Affiliation(s)
- Nuria Trevijano-Contador
- Mycology Reference Laboratory; National Centre for Microbiology; Instituto de Salud Carlos III; Madrid, Spain
| | - Oscar Zaragoza
- Mycology Reference Laboratory; National Centre for Microbiology; Instituto de Salud Carlos III; Madrid, Spain
| |
Collapse
|
115
|
Browne N, Surlis C, Kavanagh K. Thermal and physical stresses induce a short-term immune priming effect in Galleria mellonella larvae. JOURNAL OF INSECT PHYSIOLOGY 2014; 63:21-26. [PMID: 24561359 DOI: 10.1016/j.jinsphys.2014.02.006] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/08/2013] [Revised: 02/11/2014] [Accepted: 02/12/2014] [Indexed: 06/03/2023]
Abstract
Exposure of larvae of Galleria mellonella larvae to mild physical (i.e. shaking) or thermal stress for 24h increased their ability to survive infection with Aspergillus fumigatus conidia however larvae stressed in a similar manner but incubated for 72h prior to infection showed no elevation in their resistance to infection with A. fumigatus. Stressed larvae demonstrated an elevated haemocyte density 24h after initiation of the stress event but this declined at 48 and 72h. Larval proteins such as apolipophorin, arylophorin and prophenoloxidase demonstrated elevated expression at 24h but not at 72h. Larvae maintained at 37°C showed increased expression of a range of antimicrobial and immune-related proteins at 24h but these decreased in expression thereafter. The results presented here indicate that G. mellonella larvae are capable of altering their immune response following exposure to mild thermal or physical stress to mount a response capable of counteracting microbial infection which reaches a peak 24h after the initiation of the priming event and then declines by 72h. A short-term immune priming effect may serve to prevent infection but maintaining an immune priming effect for longer periods may be metabolically costly and unnecessary while living within the colony of another insect.
Collapse
Affiliation(s)
- Niall Browne
- Department of Biology, NUI Maynooth, Co. Kildare, Ireland
| | - Carla Surlis
- Department of Biology, NUI Maynooth, Co. Kildare, Ireland
| | - Kevin Kavanagh
- Department of Biology, NUI Maynooth, Co. Kildare, Ireland.
| |
Collapse
|
116
|
Essential functional modules for pathogenic and defensive mechanisms in Candida albicans infections. BIOMED RESEARCH INTERNATIONAL 2014; 2014:136130. [PMID: 24757665 PMCID: PMC3976935 DOI: 10.1155/2014/136130] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/17/2013] [Accepted: 02/10/2014] [Indexed: 12/24/2022]
Abstract
The clinical and biological significance of the study of fungal pathogen Candida albicans (C. albicans) has markedly increased. However, the explicit pathogenic and invasive mechanisms of such host-pathogen interactions have not yet been fully elucidated. Therefore, the essential functional modules involved in C. albicans-zebrafish interactions were investigated in this study. Adopting a systems biology approach, the early-stage and late-stage protein-protein interaction (PPI) networks for both C. albicans and zebrafish were constructed. By comparing PPI networks at the early and late stages of the infection process, several critical functional modules were identified in both pathogenic and defensive mechanisms. Functional modules in C. albicans, like those involved in hyphal morphogenesis, ion and small molecule transport, protein secretion, and shifts in carbon utilization, were seen to play important roles in pathogen invasion and damage caused to host cells. Moreover, the functional modules in zebrafish, such as those involved in immune response, apoptosis mechanisms, ion transport, protein secretion, and hemostasis-related processes, were found to be significant as defensive mechanisms during C. albicans infection. The essential functional modules thus determined could provide insights into the molecular mechanisms of host-pathogen interactions during the infection process and thereby devise potential therapeutic strategies to treat C. albicans infection.
Collapse
|
117
|
Sowa-Jasiłek A, Zdybicka-Barabas A, Stączek S, Wydrych J, Mak P, Jakubowicz T, Cytryńska M. Studies on the role of insect hemolymph polypeptides: Galleria mellonella anionic peptide 2 and lysozyme. Peptides 2014; 53:194-201. [PMID: 24472857 DOI: 10.1016/j.peptides.2014.01.012] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/19/2013] [Revised: 01/10/2014] [Accepted: 01/10/2014] [Indexed: 11/26/2022]
Abstract
The lysozymes are well known antimicrobial polypeptides exhibiting antibacterial and antifungal activities. Their antibacterial potential is related to muramidase activity and non-enzymatic activity resembling the mode of action of cationic defense peptides. However, the mechanisms responsible for fungistatic and/or fungicidal activity of lysozyme are still not clear. In the present study, the anti-Candida albicans activity of Galleria mellonella lysozyme and anionic peptide 2 (AP2), defense factors constitutively present in the hemolymph, was examined. The lysozyme inhibited C. albicans growth in a dose-dependent manner. The decrease in the C. albicans survival rate caused by the lysozyme was accompanied by a considerable reduction of the fungus metabolic activity, as revealed by LIVE/DEAD staining. In contrast, although AP2 reduced C. albicans metabolic activity, it did not influence its survival rate. Our results suggest fungicidal action of G. mellonella lysozyme and fungistatic activity of AP2 toward C. albicans cells. In the presence of AP2, the anti-C. albicans activity of G. mellonella lysozyme increased. Moreover, when the fungus was incubated with both defense factors, true hyphae were observed besides pseudohyphae and yeast-like C. albicans cells. Atomic force microscopy analysis of the cells exposed to the lysozyme and/or AP2 revealed alterations in the cell surface topography and properties in comparison with the control cells. The results indicate synergistic action of G. mellonella AP2 and lysozyme toward C. albicans. The presence of both factors in the hemolymph of naive larvae suggests their important role in the early stages of immune response against fungi in G. mellonella.
Collapse
Affiliation(s)
- Aneta Sowa-Jasiłek
- Department of Immunobiology, Faculty of Biology and Biotechnology, Maria Curie-Skłodowska University, Akademicka 19 St., 20-033 Lublin, Poland
| | - Agnieszka Zdybicka-Barabas
- Department of Immunobiology, Faculty of Biology and Biotechnology, Maria Curie-Skłodowska University, Akademicka 19 St., 20-033 Lublin, Poland
| | - Sylwia Stączek
- Department of Immunobiology, Faculty of Biology and Biotechnology, Maria Curie-Skłodowska University, Akademicka 19 St., 20-033 Lublin, Poland
| | - Jerzy Wydrych
- Department of Comparative Anatomy and Anthropology, Faculty of Biology and Biotechnology, Maria Curie-Skłodowska University, Akademicka 19 St., 20-033 Lublin, Poland
| | - Paweł Mak
- Department of Analytical Biochemistry, Faculty of Biochemistry, Biophysics and Biotechnology, Jagiellonian University, Gronostajowa 7 St., 30-387 Krakow, Poland
| | - Teresa Jakubowicz
- Department of Immunobiology, Faculty of Biology and Biotechnology, Maria Curie-Skłodowska University, Akademicka 19 St., 20-033 Lublin, Poland
| | - Małgorzata Cytryńska
- Department of Immunobiology, Faculty of Biology and Biotechnology, Maria Curie-Skłodowska University, Akademicka 19 St., 20-033 Lublin, Poland.
| |
Collapse
|
118
|
|
119
|
Affiliation(s)
- Ilse D Jacobsen
- Research Group Microbial Immunology; Leibniz Institute for Natural Product Research and Infection Biology; Hans Knoell Institute; Jena, Germany
| |
Collapse
|
120
|
Rueda C, Cuenca-Estrella M, Zaragoza O. Paradoxical growth of Candida albicans in the presence of caspofungin is associated with multiple cell wall rearrangements and decreased virulence. Antimicrob Agents Chemother 2013; 58:1071-83. [PMID: 24295973 PMCID: PMC3910852 DOI: 10.1128/aac.00946-13] [Citation(s) in RCA: 68] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2013] [Accepted: 11/12/2013] [Indexed: 01/01/2023] Open
Abstract
In the last decade, echinocandins have emerged as an important family of antifungal drugs because of their fungicidal activity against Candida spp. Echinocandins inhibit the enzyme β-1,3-d-glucan synthase, encoded by the FKS genes, and resistance to echinocandins is associated with mutations in this gene. In addition, echinocandin exposure can produce paradoxical growth, defined as the ability to grow at high antifungal concentrations but not at intermediate concentrations. In this work, we have demonstrated that paradoxical growth of Candida albicans in the presence of caspofungin is not due to antifungal degradation or instability. Media with high caspofungin concentrations recovered from wells where C. albicans showed paradoxical growth inhibited the growth of a Candida krusei reference strain. Cells exhibiting paradoxical growth at high caspofungin concentrations showed morphological changes such as enlarged size, abnormal septa, and absence of filamentation. Chitin content increased from the MIC to high caspofungin concentrations. Despite the high chitin levels, around 23% of cells died after treatment with caspofungin, indicating that chitin is required but not sufficient to protect the cells from the fungicidal effect of caspofungin. Moreover, we found that after paradoxical growth, β-1,3-glucan was exposed at the cell wall surface. Cells grown at high caspofungin concentrations had decreased virulence in the invertebrate host Galleria mellonella. Cells grown at high caspofungin concentrations also induced a proinflammatory response in murine macrophages compared to control cells. Our work highlights important aspects about fungal adaptation to caspofungin, and although this adaptation is associated with reduced virulence, the clinical implications remain to be elucidated.
Collapse
Affiliation(s)
- Cristina Rueda
- Mycology Reference Laboratory, National Center for Microbiology, Instituto de Salud Carlos III, Majadahonda, Madrid, Spain
| | | | | |
Collapse
|
121
|
Abstract
Does cell age matter in virulence? The emergence of persister cells during chronic infections is critical for persistence of infection, but little is known how this occurs. Here, we demonstrate for the first time that the replicative age of the fungal pathogen Cryptococcus neoformans contributes to persistence during chronic meningoencephalitis. Generationally older C. neoformans cells are more resistant to hydrogen peroxide stress, macrophage intracellular killing, and antifungal agents. Older cells accumulate in both experimental rat infection and in human cryptococcosis. Mathematical modeling supports the concept that the presence of older C. neoformans cells emerges from in vivo selection pressures. We propose that advanced replicative aging is a new unanticipated virulence trait that emerges during chronic fungal infection and facilitates persistence. Therapeutic interventions that target old cells could help in the clearance of chronic infections. Our findings that the generational age of Cryptococcus neoformans cells matters in pathogenesis introduces a novel concept to eukaryotic pathogenesis research. We propose that emerging properties of aging C. neoformans cells and possibly also other fungal pathogens contribute to persistence and virulence. Whereas the replicative life span of strains may not matter for virulence per se, age-related resilience and thus the generational age of individual C. neoformans cells within a pathogen population could greatly affect persistence of the pathogen population and therefore impact outcome.
Collapse
|
122
|
LPS structure and PhoQ activity are important for Salmonella Typhimurium virulence in the Galleria mellonella infection model [corrected]. PLoS One 2013; 8:e73287. [PMID: 23951347 PMCID: PMC3738532 DOI: 10.1371/journal.pone.0073287] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2013] [Accepted: 07/18/2013] [Indexed: 11/19/2022] Open
Abstract
The larvae of the wax moth, Galleria mellonella, have been used experimentally to host a range of bacterial and fungal pathogens. In this study we evaluated the suitability of G. mellonella as an alternative animal model of Salmonella infection. Using a range of inoculum doses we established that the LD₅₀ of SalmonellaTyphimurium strain NCTC 12023 was 3.6 × 10³ bacteria per larva. Further, a set of isogenic mutant strains depleted of known virulence factors was tested to identify determinants essential for S. Typhimurium pathogenesis. Mutants depleted of one or both of the type III secretion systems encoded by Salmonella Pathogenicity Islands 1 and 2 showed no virulence defect. In contrast, we observed reduced pathogenic potential of a phoQ mutant indicating an important role for the PhoPQ two-component signal transduction system. Lipopolysaccharide (LPS) structure was also shown to influence Salmonella virulence in G. mellonella. A waaL(rfaL) mutant, which lacks the entire O-antigen (OAg), was virtually avirulent, while a wzz(ST)/wzz(fepE) double mutant expressing only a very short OAg was highly attenuated for virulence. Furthermore, shortly after infection both LPS mutant strains showed decreased replication when compared to the wild type in a flow cytometry-based competitive index assay. In this study we successfully established a G. mellonella model of S. Typhimurium infection. By identifying PhoQ and LPS OAg length as key determinants of virulence in the wax moth larvae we proved that there is an overlap between this and other animal model systems, thus confirming that the G. mellonella infection model is suitable for assessing aspects of Salmonella virulence function.
Collapse
|
123
|
Junqueira JC. Galleria mellonella as a model host for human pathogens: recent studies and new perspectives. Virulence 2013; 3:474-6. [PMID: 23211681 PMCID: PMC3524145 DOI: 10.4161/viru.22493] [Citation(s) in RCA: 65] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The number of studies using G. mellonella as a model host for human pathogens has increased significantly in the last few years. Important studies were published from different countries for evaluating the pathogenesis of bacterial and fungal infections and for exploring the host defenses against pathogens. Therefore, standardized conditions for the use of G. melonella larvae need to be established. Recent research showed that the deprivation of G. mellonella larvae of food during the experiment caused a reduction in immune responses and an increased susceptibility to infection, suggesting that incubating of larvae in the presence or absence of nutrition may affect the results and comparisons among different laboratories.
Collapse
Affiliation(s)
- Juliana Campos Junqueira
- Department of Biosciences and Oral Diagnosis, São José dos Campos Dental School, Universidade Estadual Paulista/UNESP, São Paulo, Brazil.
| |
Collapse
|
124
|
Abstract
Virulence has been proposed to be an emergent property, which by definition implies that it is not reducible to its components, but this application of a philosophical concept to the host-microbe interaction has not been experimentally tested. The goals of our study were to analyze the correlation of the phenotype with the ability to cause disease and to determine the dynamics of an experimental cryptococcal infection in Galleria mellonella and Acanthamoeba castellanii. By studying the outcome of infection as host death, we showed that the dynamics of virulence in the G. mellonella/Cryptococcus neoformans interaction follow a predictable pattern. We also found that the experimental temperature and not the presence of virulence factors was a critical parameter defining the pathogenic potential of cryptococcal species. Our results established that cryptococcal species not considered pathogenic could be pathogens given suitable conditions. Our results support the idea that virulence is an emergent property that cannot be easily predicted by a reductionist approach and yet it behaves as a deterministic system in a lepidopteran cryptococcal infection. These findings provide a road map for evaluating whether host-microbe interactions in other systems are chaotic, deterministic, or stochastic, including those with public health importance. Virulence is a complex phenotype that cannot be easily studied by analyzing its individual components in isolation. By studying the outcome of infection as the death of the host, we found that a given microbial phenotype does not necessarily correlate with its ability to cause disease and that the presence of so-called virulence factors does not predict pathogenicity, consistent with the notion that virulence is an emergent property. This paper reports that the dynamics of virulence in Galleria mellonella larvae infected with the fungus Cryptococcus neoformans follows a predictable pattern. Establishing that virulence is an emergent property is important because it implies that it is not reducible to its components, and consequently, this phenomenon needs to be studied by a holistic approach.
Collapse
|
125
|
Browne N, Kavanagh K. Developing the potential of using Galleria mellonella larvae as models for studying brain infection by Listeria monocytogenes. Virulence 2013; 4:271-2. [PMID: 23552811 PMCID: PMC3710329 DOI: 10.4161/viru.24174] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
|
126
|
Scorzoni L, de Lucas MP, Mesa-Arango AC, Fusco-Almeida AM, Lozano E, Cuenca-Estrella M, Mendes-Giannini MJ, Zaragoza O. Antifungal efficacy during Candida krusei infection in non-conventional models correlates with the yeast in vitro susceptibility profile. PLoS One 2013; 8:e60047. [PMID: 23555877 PMCID: PMC3610750 DOI: 10.1371/journal.pone.0060047] [Citation(s) in RCA: 113] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2012] [Accepted: 02/20/2013] [Indexed: 12/28/2022] Open
Abstract
The incidence of opportunistic fungal infections has increased in recent decades due to the growing proportion of immunocompromised patients in our society. Candida krusei has been described as a causative agent of disseminated fungal infections in susceptible patients. Although its prevalence remains low among yeast infections (2-5%), its intrinsic resistance to fluconazole makes this yeast important from epidemiologic aspects. Non mammalian organisms are feasible models to study fungal virulence and drug efficacy. In this work we have used the lepidopteran Galleria mellonella and the nematode Caenorhabditis elegans as models to assess antifungal efficacy during infection by C. krusei. This yeast killed G. mellonella at 25, 30 and 37°C and reduced haemocytic density. Infected larvae melanized in a dose-dependent manner. Fluconazole did not protect against C. krusei infection, in contrast to amphotericin B, voriconazole or caspofungin. However, the doses of these antifungals required to obtain larvae protection were always higher during C. krusei infection than during C. albicans infection. Similar results were found in the model host C. elegans. Our work demonstrates that non mammalian models are useful tools to investigate in vivo antifungal efficacy and virulence of C. krusei.
Collapse
Affiliation(s)
- Liliana Scorzoni
- Mycology Reference Laboratory, National Centre for Microbiology, Instituto de Salud Carlos III, Madrid, Spain
- Laboratório de Micologia Clínica, Faculdade de Ciências Farmacêuticas, Universidade Estadual Paulista de São Paulo, Araraquara, Brazil
| | - Maria Pilar de Lucas
- Department of Cellular Biology, National Centre for Microbiology, Instituto de Salud Carlos III, Madrid, Spain
| | - Ana Cecilia Mesa-Arango
- Mycology Reference Laboratory, National Centre for Microbiology, Instituto de Salud Carlos III, Madrid, Spain
- Group of Investigative Dermatology, University of Antioquia, Medellín, Colombia
| | - Ana Marisa Fusco-Almeida
- Laboratório de Micologia Clínica, Faculdade de Ciências Farmacêuticas, Universidade Estadual Paulista de São Paulo, Araraquara, Brazil
| | - Encarnación Lozano
- Department of Cellular Biology, National Centre for Microbiology, Instituto de Salud Carlos III, Madrid, Spain
| | - Manuel Cuenca-Estrella
- Mycology Reference Laboratory, National Centre for Microbiology, Instituto de Salud Carlos III, Madrid, Spain
| | - Maria Jose Mendes-Giannini
- Laboratório de Micologia Clínica, Faculdade de Ciências Farmacêuticas, Universidade Estadual Paulista de São Paulo, Araraquara, Brazil
- * E-mail: (MJMG); (OZ)
| | - Oscar Zaragoza
- Mycology Reference Laboratory, National Centre for Microbiology, Instituto de Salud Carlos III, Madrid, Spain
- * E-mail: (MJMG); (OZ)
| |
Collapse
|
127
|
Arvanitis M, Glavis-Bloom J, Mylonakis E. Invertebrate models of fungal infection. Biochim Biophys Acta Mol Basis Dis 2013; 1832:1378-83. [PMID: 23517918 DOI: 10.1016/j.bbadis.2013.03.008] [Citation(s) in RCA: 85] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2012] [Revised: 03/07/2013] [Accepted: 03/11/2013] [Indexed: 10/27/2022]
Abstract
The morbidity, mortality and economic burden associated with fungal infections, together with the emergence of fungal strains resistant to current antimicrobial agents, necessitate broadening our understanding of fungal pathogenesis and discovering new agents to treat these infections. Using invertebrate hosts, especially the nematode Caenorhabditis elegans and the model insects Drosophila melanogaster and Galleria mellonella, could help achieve these goals. The evolutionary conservation of several aspects of the innate immune response between invertebrates and mammals makes the use of these simple hosts an effective and fast screening method for identifying fungal virulence factors and testing potential antifungal compounds. The purpose of this review is to compare several model hosts that have been used in experimental mycology to-date and to describe their different characteristics and contribution to the study of fungal virulence and the detection of compounds with antifungal properties. This article is part of a Special Issue entitled: Animal Models of Disease.
Collapse
Affiliation(s)
- Marios Arvanitis
- Department of Medicine, Warren Alpert Medical School of Brown University, Providence, RI 02903, USA
| | | | | |
Collapse
|
128
|
Epidemiology, antifungal susceptibility, and pathogenicity of Candida africana isolates from the United Kingdom. J Clin Microbiol 2013; 51:967-72. [PMID: 23303503 DOI: 10.1128/jcm.02816-12] [Citation(s) in RCA: 61] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Candida africana was previously proposed as a new species within the Candida albicans species complex, together with C. albicans and C. dubliniensis, although further phylogenetic analyses better support its status as an unusual variant within C. albicans. Here we show that C. africana can be distinguished from C. albicans and C. dubliniensis by pyrosequencing of a short region of ITS2, and we have evaluated its occurrence in clinical samples by pyrosequencing all presumptive isolates of C. albicans submitted to the Mycology Reference Laboratory over a 9-month period. The C. albicans complex constituted 826/1,839 (44.9%) of yeast isolates received over the study period and included 783 isolates of C. albicans, 28 isolates of C. dubliniensis, and 15 isolates of C. africana. In agreement with previous reports, C. africana was isolated exclusively from genital specimens, in women in the 18-to-35-year age group. Indeed, C. africana constituted 15/251 (6%) of "C. albicans" isolates from female genital specimens during the study period. C. africana isolates were germ tube positive, grew significantly more slowly than C. albicans and C. dubliniensis on conventional mycological media, could be distinguished from the other members of the C. albicans complex by appearance on chromogenic agar, and were incapable of forming chlamydospores. Here we present the detailed evaluation of epidemiological, phenotypic, and clinical features and antifungal susceptibility profiles of United Kingdom isolates of C. africana. Furthermore, we demonstrate that C. africana is significantly less pathogenic than C. albicans and C. dubliniensis in the Galleria mellonella insect systemic infection model.
Collapse
|
129
|
Thomaz L, García-Rodas R, Guimarães AJ, Taborda CP, Zaragoza O, Nosanchuk JD. Galleria mellonella as a model host to study Paracoccidioides lutzii and Histoplasma capsulatum. Virulence 2013; 4:139-46. [PMID: 23302787 DOI: 10.4161/viru.23047] [Citation(s) in RCA: 60] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Non-mammalian models have been used to investigate fungal virulence. In this work we have explored the use of Galleria mellonella as an infection model for the pathogenic dimorphic fungi Histoplasma capsulatum and Paracoccidioides lutzii. In mammalian models these fungi cause similar infections, and disease outcomes are influenced by the quantity of the infective inocula. We describe a similar aspect in a G. mellonella model and characterize the pathogenesis features in this system. Infection with P. lutzii or H. capsulatum, in all inoculum used, killed larvae at 25 and 37°C. However, there was a lack of correlation between the number of yeast cells used for infection and the time to larvae death, which may indicate that the fungi induce protective responses in a dynamic manner as the lowest concentrations of fungi induced the most rapid death. For both fungi, the degree of larvae melanization was directly proportional to the inocula size, and this effect was visibly more apparent at 37°C. Histological evaluation of the larvae showed a correlation between the inoculum and granuloma-like formation. Our results suggest that G. mellonella is a potentially useful model to study virulence of dimorphic fungi.
Collapse
Affiliation(s)
- Luciana Thomaz
- Institute of Biomedical Science, Department of Microbiology, University of São Paulo, São Paulo, Brazil.
| | | | | | | | | | | |
Collapse
|
130
|
Utility of insects for studying human pathogens and evaluating new antimicrobial agents. ADVANCES IN BIOCHEMICAL ENGINEERING/BIOTECHNOLOGY 2013; 135:1-25. [PMID: 23604210 DOI: 10.1007/10_2013_194] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/06/2022]
Abstract
Insect models, such as Galleria mellonella and Drosophila melanogaster have significant ethical, logistical, and economic advantages over mammalian models for the studies of infectious diseases. Using these models, various pathogenic microbes have been studied and many novel virulence genes have been identified. Notably, because insects are susceptible to a wide variety of human pathogens and have immune responses similar to those of mammals, they offer the opportunity to understand innate immune responses against human pathogens better. It is important to note that insect pathosystems have also offered a simple strategy to evaluate the efficacy and toxicity of many antimicrobial agents. Overall, insect models provide a rapid, inexpensive, and reliable way as complementary hosts to conventional vertebrate animal models to study pathogenesis and antimicrobial agents.
Collapse
|
131
|
Mesa-Arango AC, Forastiero A, Bernal-Martínez L, Cuenca-Estrella M, Mellado E, Zaragoza O. The non-mammalian host Galleria mellonella can be used to study the virulence of the fungal pathogen Candida tropicalis and the efficacy of antifungal drugs during infection by this pathogenic yeast. Med Mycol 2012; 51:461-72. [PMID: 23170962 DOI: 10.3109/13693786.2012.737031] [Citation(s) in RCA: 90] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
Although Candida tropicalis is a frequent cause of invasive fungal diseases, its interaction with the host remains poorly studied. Galleria mellonella is a Lepidoptera model which offers a useful tool to study virulence of different microorganisms and drug efficacy. In this work we investigated the virulence of C. tropicalis in G. mellonella at different temperatures and the efficacy of antifungal drugs in this infection model. When larvae were infected with yeast inocula suspensions of different concentrations (4 × 10(6), 2 × 10(6), 10(6) and 5 × 10(5) cells/larva), we observed a dose-dependent effect on the killing of the insect (50% survival ranging from 1.4 ± 0.8 to 8.8 ± 1.2 days with the higher and lower inocula, respectively). Candida tropicalis killed G. mellonella larvae at both 30°C and 37°C, although at 37°C the virulence was more evident. Haemocytes phagocytosed C. tropicalis cells after 2 hours of infection, although the phagocytosis rate was lower when compared with other fungal pathogens, such as Cryptococcus neoformans. Moreover, the haemocyte density in the haemolymph decreased during infection and the yeast formed pseudohyphae in G. mellonella. The efficacy of amphotericin B, caspofungin, fluconazole and voriconazole was tested at different concentrations, and a protective effect was observed with all the drugs at concentrations equivalent to therapeutic dose. Fungal burden increased in infected larvae during time of infection and amphotericin B and fluconazole reduced the number of colony-forming units in the worms. Moreover, antifungal treatment was associated with the presence of cell aggregates around infected areas. We conclude that G. mellonella offers a simple and feasible model to study C. tropicalis virulence and drug efficacy.
Collapse
Affiliation(s)
- Ana Cecilia Mesa-Arango
- Mycology Reference Laboratory, National Centre for Microbiology, Instituto de Salud Carlos III, Majadahonda, Madrid, Spain
| | | | | | | | | | | |
Collapse
|
132
|
Banville N, Browne N, Kavanagh K. Effect of nutrient deprivation on the susceptibility of Galleria mellonella larvae to infection. Virulence 2012; 3:497-503. [PMID: 23076277 DOI: 10.4161/viru.21972] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Larvae of Galleria mellonella are widely used to study the virulence of microbial pathogens and for assessing the potency of antimicrobial agents. This work examined the effect of nutritional deprivation on the ability of larvae to withstand infection in order to establish standardized conditions for the treatment of larvae for in vivo testing. Larvae deprived of food for seven days demonstrated an increased susceptibility to infection by the yeast Candida albicans. These larvae displayed a lower density of hemocytes compared with controls but hemocytes from starved and control larvae demonstrated the same ability to kill yeast cells. Hemolymph from starved larvae demonstrated reduced expression of a range of antimicrobial peptides (e.g., lipocalin) and immune proteins (e.g., apolipophorin and arylphorin). Deprivation of G. mellonella larvae of food leads to a reduction in the cellular and immune responses and an increased susceptibility to infection. Researchers utilizing these larvae should ensure adequate food is provided to larvae in order to allow valid comparisons to be made between results from different laboratories.
Collapse
Affiliation(s)
- Nessa Banville
- Department of Biology, National University of Ireland, Maynooth, Ireland
| | | | | |
Collapse
|
133
|
Coughlan A, Breed SM, Ashraf C, Cardinale JA, Hall MM, Towler MR. Does elevating silver content in zinc-based glass polyalkenoate cements increase their antibacterial efficacy against two common bacteria using the agar gel diffusion method? J Biomater Appl 2012; 27:840-7. [DOI: 10.1177/0885328211427775] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
The authors have previously shown that it is possible to incorporate silver into a soda-zinc-silicate glass and subsequently form a glass polyalkenoate cement from it. The objective of the research described herein is to determine if incremental increases in the silver content of these glass polyalkenoate cements will increase their antibacterial efficacy against gram-positive and gram-negative bacteria using the accepted spread plate method. Four glass polyalkenoate cements were formulated; three contained increasing amounts of silver incorporated into them (cements A, B, and C, containing 0.33 mol%, 0.66 mol%, and 0.99 mol% silver, respectively) and a fourth contained no silver, which acted as a control (control cement). The handling properties of the glass polyalkenoate cements were evaluated, where working times were around 2 min and setting times ranged from 1 h 17 min to 2 h 41 min. Inductively coupled plasma atomic emission spectroscopy was employed to determine silver ion release with cement maturation for up to 14 days. The majority of silver ions were released within the first 24 h, with up to 2 mg/L cumulative ion release recorded up to 14 days. The antibacterial properties of the coatings were evaluated against Staphylococcus aureus and Pseudomonas aeruginosa bacteria. The silver-glass polyalkenoate cements exhibited antibacterial effect against both bacterial strains. The maximum inhibition zones recorded against S. aureus was 14.8 mm (SD ± 1.11) and against P. aeruginosa was 20.6 mm (SD ± 0.81). Cement B had a greater antibacterial effect compared to cement A, however, cements B and C had comparable antibacterial effects after 14 days even though cement C contained 0.33 mol% more silver than B. This indicates that by increasing the silver content in these cements, the antibacterial efficacy increases to a point, but there is a threshold where further silver ion release does not increase the antibacterial effect.
Collapse
Affiliation(s)
- A Coughlan
- Inamori School of Engineering, Alfred University, Alfred, NY, USA
| | - SM Breed
- Inamori School of Engineering, Alfred University, Alfred, NY, USA
| | - C Ashraf
- Inamori School of Engineering, Alfred University, Alfred, NY, USA
| | - JA Cardinale
- College of Liberal Arts and Sciences, Alfred University, Alfred, NY, USA
| | - MM Hall
- Inamori School of Engineering, Alfred University, Alfred, NY, USA
| | - MR Towler
- Inamori School of Engineering, Alfred University, Alfred, NY, USA
- Material Surface Science Institute, University of Limerick, Limerick, Ireland
| |
Collapse
|
134
|
Of model hosts and man: using Caenorhabditis elegans, Drosophila melanogaster and Galleria mellonella as model hosts for infectious disease research. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2012; 710:11-7. [PMID: 22127881 DOI: 10.1007/978-1-4419-5638-5_2] [Citation(s) in RCA: 72] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
The use of invertebrate model hosts has increased in popularity due to numerous advantages of invertebrates over mammalian models, including ethical, logistical and budgetary features. This review provides an introduction to three model hosts, the nematode Caenorhabditis elegans, the fruit fly Drosophila melanogaster and the larvae of Galleria mellonella, the greater wax moth. It highlights principal experimental advantages of each model, for C. elegans the ability to run high-throughput assays, for D. melanogaster the evolutionarily conserved innate immune response, and for G. mellonella the ability to conduct experiments at 37°C and easily inoculate a precise quantity of pathogen. It additionally discusses recent research that has been conducted with each host to identify pathogen virulence factors, study the immune response, and evaluate potential antimicrobial compounds, focusing principally on fungal pathogens.
Collapse
|
135
|
Abstract
Insects are convenient models for assessing the virulence of microbial pathogens or for assessing the -efficacy of antimicrobial drugs and give results comparable to those that can be obtained using mammals. Galleria mellonella larvae are easy to purchase and inoculate and provide results within 48 h. Various parameters may be used to monitor the effect of a pathogen on the insect and, as a consequence, measure its relative virulence. Larval death, changes in immune cells (haemocytes) numbers, or the extent of proliferation of the pathogen within the insect haemocoel are good indicators of virulence and of the insect's immune response. Analysing the humoral immune response also gives insight into the interaction of the pathogen with the insect. Changes in gene expression or the expression of key antimicrobial peptides provide data on this element of the insect's response and, through extrapolation, how the mammalian immune system might respond. G. mellonella larvae, therefore, provide a quick and convenient means of measuring microbial virulence and are a useful alternative to the use of mammals for this type of screening.
Collapse
|
136
|
MacCallum DM. Hosting infection: experimental models to assay Candida virulence. Int J Microbiol 2011; 2012:363764. [PMID: 22235206 PMCID: PMC3253448 DOI: 10.1155/2012/363764] [Citation(s) in RCA: 62] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2011] [Accepted: 10/13/2011] [Indexed: 02/01/2023] Open
Abstract
Although normally commensals in humans, Candida albicans, Candida tropicalis, Candida parapsilosis, Candida glabrata, and Candida krusei are capable of causing opportunistic infections in individuals with altered physiological and/or immunological responses. These fungal species are linked with a variety of infections, including oral, vaginal, gastrointestinal, and systemic infections, with C. albicans the major cause of infection. To assess the ability of different Candida species and strains to cause infection and disease requires the use of experimental infection models. This paper discusses the mucosal and systemic models of infection available to assay Candida virulence and gives examples of some of the knowledge that has been gained to date from these models.
Collapse
Affiliation(s)
- Donna M. MacCallum
- Aberdeen Fungal Group, School of Medical Sciences, Institute of Medical Sciences, University of Aberdeen, Foresterhill, Aberdeen, AB25 2ZD, UK
| |
Collapse
|
137
|
Junqueira JC, Fuchs BB, Muhammed M, Coleman JJ, Suleiman JMAH, Vilela SFG, Costa ACBP, Rasteiro VMC, Jorge AOC, Mylonakis E. Oral Candida albicans isolates from HIV-positive individuals have similar in vitro biofilm-forming ability and pathogenicity as invasive Candida isolates. BMC Microbiol 2011; 11:247. [PMID: 22053894 PMCID: PMC3217868 DOI: 10.1186/1471-2180-11-247] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2011] [Accepted: 11/04/2011] [Indexed: 11/10/2022] Open
Abstract
Background Candida can cause mucocutaneous and/or systemic infections in hospitalized and immunosuppressed patients. Most individuals are colonized by Candida spp. as part of the oral flora and the intestinal tract. We compared oral and systemic isolates for the capacity to form biofilm in an in vitro biofilm model and pathogenicity in the Galleria mellonella infection model. The oral Candida strains were isolated from the HIV patients and included species of C. albicans, C. glabrata, C. tropicalis, C. parapsilosis, C. krusei, C. norvegensis, and C. dubliniensis. The systemic strains were isolated from patients with invasive candidiasis and included species of C. albicans, C. glabrata, C. tropicalis, C. parapsilosis, C. lusitaniae, and C. kefyr. For each of the acquired strains, biofilm formation was evaluated on standardized samples of silicone pads and acrylic resin. We assessed the pathogenicity of the strains by infecting G. mellonella animals with Candida strains and observing survival. Results The biofilm formation and pathogenicity in Galleria was similar between oral and systemic isolates. The quantity of biofilm formed and the virulence in G. mellonella were different for each of the species studied. On silicone pads, C. albicans and C. dubliniensis produced more biofilm (1.12 to 6.61 mg) than the other species (0.25 to 3.66 mg). However, all Candida species produced a similar biofilm on acrylic resin, material used in dental prostheses. C. albicans, C. dubliniensis, C. tropicalis, and C. parapsilosis were the most virulent species in G. mellonella with 100% of mortality, followed by C. lusitaniae (87%), C. novergensis (37%), C. krusei (25%), C. glabrata (20%), and C. kefyr (12%). Conclusions We found that on silicone pads as well as in the Galleria model, biofilm formation and virulence depends on the Candida species. Importantly, for C. albicans the pathogenicity of oral Candida isolates was similar to systemic Candida isolates, suggesting that Candida isolates have similar biofilm-forming ability and virulence regardless of the infection site from which it was isolated.
Collapse
Affiliation(s)
- Juliana C Junqueira
- Department of Biosciences and Oral Diagnosis, Univ Estadual Paulista/UNESP, Eng, Francisco José Longo, São José dos Campos, Brazil.
| | | | | | | | | | | | | | | | | | | |
Collapse
|
138
|
Lionakis MS. Drosophila and Galleria insect model hosts: new tools for the study of fungal virulence, pharmacology and immunology. Virulence 2011; 2:521-7. [PMID: 22186764 PMCID: PMC3260546 DOI: 10.4161/viru.2.6.18520] [Citation(s) in RCA: 92] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2011] [Accepted: 10/25/2011] [Indexed: 11/19/2022] Open
Abstract
Over recent years we have witnessed the emergence of several non-vertebrate mini-hosts as alternative pathosystems for the study of fungal disease. These heterologous organisms have unique advantages, as they are economical, ethically expedient, and facile to use. Hence, they are amenable to high-throughput screening studies of fungal genomes for identification of novel virulence genes and of chemical libraries for discovery of new antifungal compounds. In addition, because they have evolutionarily conserved immunity they offer the opportunity to better understand innate immune responses against medically important fungi. In this review, we discuss how the insects Drosophila melanogaster and Galleria mellonella can be employed for the study of various facets of host-fungal interactions as complementary hosts to conventional vertebrate animal models.
Collapse
Affiliation(s)
- Michail S Lionakis
- Clinical Mycology Unit, Laboratory of Molecular Immunology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA.
| |
Collapse
|
139
|
Coleman JJ, Muhammed M, Kasperkovitz PV, Vyas JM, Mylonakis E. Fusarium pathogenesis investigated using Galleria mellonella as a heterologous host. Fungal Biol 2011; 115:1279-89. [PMID: 22115447 DOI: 10.1016/j.funbio.2011.09.005] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2011] [Revised: 09/21/2011] [Accepted: 09/22/2011] [Indexed: 10/16/2022]
Abstract
Members of the fungal genus Fusarium are capable of manifesting in a multitude of clinical infections, most commonly in immunocompromised patients. In order to better understand the interaction between the fungus and host, we have developed the larvae of the greater wax moth, Galleria mellonella, as a heterologous host for fusaria. When conidia are injected into the haemocoel of this Lepidopteran system, both clinical and environmental isolates of the fungus are able to kill the larvae at 37 °C, although killing occurs more rapidly when incubated at 30 °C. This killing was dependent on several other factors besides temperature, including the Fusarium strain, the number of conidia injected, and the conidia morphology, where macroconidia are more virulent than their microconidia counterpart. There was a correlation in the killing rate of Fusarium spp. when evaluated in G. mellonella and a murine model. In vivo studies indicated G. mellonella haemocytes were capable of initially phagocytosing both conidial morphologies. The G. mellonella system was also used to evaluate antifungal agents, and amphotericin B was able to confer a significant increase in survival to Fusarium-infected larvae. The G. mellonella-Fusarium pathogenicity system revealed that virulence of Fusarium spp. is similar, regardless of the origin of the isolate, and that mammalian endothermy is a major deterrent for Fusarium infection and therefore provides a suitable alternative to mammalian models to investigate the interaction between the host and this increasingly important fungal pathogen.
Collapse
Affiliation(s)
- Jeffrey J Coleman
- Harvard Medical School, Massachusetts General Hospital, Division of Infectious Diseases, Boston, MA 02114, USA.
| | | | | | | | | |
Collapse
|
140
|
Dermatophyte virulence factors: identifying and analyzing genes that may contribute to chronic or acute skin infections. Int J Microbiol 2011; 2012:358305. [PMID: 21977036 PMCID: PMC3185252 DOI: 10.1155/2012/358305] [Citation(s) in RCA: 59] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2011] [Accepted: 08/09/2011] [Indexed: 01/15/2023] Open
Abstract
Dermatophytes are prevalent causes of cutaneous mycoses and, unlike many other fungal pathogens, are able to cause disease in immunocompetent individuals. They infect keratinized tissue such as skin, hair, and nails, resulting in tinea infections, including ringworm. Little is known about the molecular mechanisms that underlie the ability of these organisms to establish and maintain infection. The recent availability of genome sequence information and improved genetic manipulation have enabled researchers to begin to identify and study the role of virulence factors of dermatophytes. This paper will summarize our current understanding of dermatophyte virulence factors and discuss future directions for identifying and testing virulence factors.
Collapse
|
141
|
Adaptation, adhesion and invasion during interaction of Candida albicans with the host – Focus on the function of cell wall proteins. Int J Med Microbiol 2011; 301:384-9. [DOI: 10.1016/j.ijmm.2011.04.004] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
|
142
|
Andrejko M, Mizerska-Dudka M. Elastase B of Pseudomonas aeruginosa stimulates the humoral immune response in the greater wax moth, Galleria mellonella. J Invertebr Pathol 2011; 107:16-26. [DOI: 10.1016/j.jip.2010.12.015] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2010] [Revised: 12/20/2010] [Accepted: 12/31/2010] [Indexed: 11/16/2022]
|
143
|
Olsen RJ, Watkins ME, Cantu CC, Beres SB, Musser JM. Virulence of serotype M3 Group A Streptococcus strains in wax worms (Galleria mellonella larvae). Virulence 2011; 2:111-9. [PMID: 21258213 DOI: 10.4161/viru.2.2.14338] [Citation(s) in RCA: 74] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
Group A Streptococcus (GAS) causes human infections that range in severity from pharyngitis ("strep-throat") to necrotizing fasciitis ("flesh-eating disease"). To facilitate investigation of the molecular basis of host-pathogen interactions, infection models capable of rapidly screening for differences in GAS strain virulence are needed. To this end, we developed a Galleria mellonella larvae (wax worm) model of invasive GAS infection and used it to compare the virulence of serotype M3 GAS strains. We found that GAS causes severe tissue damage and kills wax worms in a dose-dependent manner. The virulence of genetically distinct GAS strains was compared by Kaplan-Meier survival analysis and determining 50% lethal doses (LD 50). Host-pathogen interactions were further characterized using quantitative culture, histopathology and TaqMan assays. GAS strains known to be highly pathogenic in mice and monkeys caused significantly lower survival and had significantly lower LD 50s in wax worms than GAS strains associated with attenuated virulence or asymptomatic carriage. Furthermore, isogenic inactivation of proven virulence factors resulted in a significantly increased LD 50 and decreased lesion size compared to the wild-type strain, a finding that also strongly correlates with animal studies. Importantly, survival analysis and LD 50 determination in wax worms supported our hypothesis that a newly emerged GAS subclone that is epidemiologically associated with more human necrotizing fasciitis cases than its progenitor lineage has significantly increased virulence. We conclude that GAS virulence in wax worms strongly correlates with the data obtained in vertebrate models, and thus, the Galleria mellonella larva is a useful host organism to study GAS pathogenesis.
Collapse
Affiliation(s)
- Randall J Olsen
- The Methodist Hospital Research Institute, Houston, TX, USA.
| | | | | | | | | |
Collapse
|
144
|
Fallon JP, Reeves EP, Kavanagh K. The Aspergillus fumigatus toxin fumagillin suppresses the immune response of Galleria mellonella larvae by inhibiting the action of haemocytes. MICROBIOLOGY-SGM 2011; 157:1481-1488. [PMID: 21349977 DOI: 10.1099/mic.0.043786-0] [Citation(s) in RCA: 57] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Larvae of Galleria mellonella are widely used to evaluate microbial virulence and to assess the in vivo efficacy of antimicrobial agents. The aim of this work was to examine the ability of an Aspergillus fumigatus toxin, fumagillin, to suppress the immune response of larvae. Administration of fumagillin to larvae increased their susceptibility to subsequent infection with A. fumigatus conidia (P = 0.0052). It was demonstrated that a dose of 2 µg fumagillin ml⁻¹ reduced the ability of insect immune cells (haemocytes) to kill opsonized cells of Candida albicans (P = 0.039) and to phagocytose A. fumigatus conidia (P = 0.016). Fumagillin reduced the oxygen uptake of haemocytes and decreased the translocation of a p47 protein which is homologous to p47(phox), a protein essential for the formation of a functional NADPH oxidase complex required for superoxide production. In addition, toxin-treated haemocytes showed reduced levels of degranulation as measured by the release of a protein showing reactivity to an anti-myeloperoxidase antibody (P<0.049) that was subsequently identified by liquid chromatography-MS analysis as prophenoloxidase. This work demonstrates that fumagillin suppresses the immune response of G. mellonella larvae by inhibiting the action of haemocytes and thus renders the larvae susceptible to infection. During growth of the fungus in the larvae, this toxin, along with others, may facilitate growth by suppressing the cellular immune response.
Collapse
Affiliation(s)
- John P Fallon
- Medical Mycology Unit, Department of Biology, National Institute for Cellular Biotechnology, National University of Ireland Maynooth, Co. Kildare, Ireland
| | - Emer P Reeves
- Respiratory Research Division, Department of Medicine, Royal College of Surgeons in Ireland, Beaumont Hospital, Dublin 9, Ireland
| | - Kevin Kavanagh
- Medical Mycology Unit, Department of Biology, National Institute for Cellular Biotechnology, National University of Ireland Maynooth, Co. Kildare, Ireland
| |
Collapse
|
145
|
Kelly J, Kavanagh K. Caspofungin primes the immune response of the larvae of Galleria mellonella and induces a non-specific antimicrobial response. J Med Microbiol 2011; 60:189-196. [DOI: 10.1099/jmm.0.025494-0] [Citation(s) in RCA: 57] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The echinocandins (e.g. caspofungin) function by inhibiting the synthesis of 1,3-β-glucan in the fungal cell wall. While the potent antifungal activity of caspofungin has been well characterized in mammals, this study investigated the in vivo antifungal effect of caspofungin using larvae of the insect Galleria mellonella. Caspofungin was successful in increasing the survival of larvae that were inoculated with Candida albicans 1 h before the drug was administered, particularly when a concentration of 0.19 μg ml−1 was used. Pre-injecting larvae with caspofungin also increased their survival when they were inoculated with either Staphylococcus aureus or C. albicans. Caspofungin administration resulted in an increase in the number of circulating immune cells (haemocytes), an increase in the expression of the genes encoding IMPI and transferrin, and an increase in the expression of a number of proteins (identified by liquid chromatography–mass spectrometry) some of which have immune functions. This work indicates that administration of caspofungin can increase the survival of infected G. mellonella larvae, and this is due to the antifungal properties of caspofungin and also to the ability of caspofungin to prime the insect's immune response.
Collapse
Affiliation(s)
- Judy Kelly
- Medical Mycology Unit, Department of Biology, National Institute for Cellular Biotechnology, NUI Maynooth, County Kildare, Ireland
| | - Kevin Kavanagh
- Medical Mycology Unit, Department of Biology, National Institute for Cellular Biotechnology, NUI Maynooth, County Kildare, Ireland
| |
Collapse
|
146
|
Sequenced dermatophyte strains: growth rate, conidiation, drug susceptibilities, and virulence in an invertebrate model. Fungal Genet Biol 2010; 48:335-41. [PMID: 21145410 DOI: 10.1016/j.fgb.2010.11.010] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2010] [Revised: 11/18/2010] [Accepted: 11/23/2010] [Indexed: 11/24/2022]
Abstract
Although dermatophytes are the most common cause of fungal infections in the world, their basic biology is not well understood. The recent sequencing and annotation of the genomes of five representative dermatophyte species allows for the creation of hypotheses as to how they cause disease and have adapted to their distinct environments. An understanding of the microbiology of these strains will be essential for testing these hypotheses. This study is the first to generally characterize these five sequenced strains of dermatophytes for their microbiological aspects. We measured the growth rate on solid medium and found differences between species, with Microsporum gypseum CBS118893 having the fastest growth and Trichophyton rubrum CBS118892 the slowest. We also compared different media for conidia production and found that the highest numbers of conidia were produced when dermatophytes were grown on MAT agar. We determined the Minimum Inhibitory Concentration (MIC) of nine antifungal agents and confirmed susceptibility to antifungals commonly used as selectable markers. Finally, we tested virulence in the Galleria mellonella (wax moth) larvae model but found the results variable. These results increase our understanding of the microbiology and molecular biology of these dermatophyte strains and will be of use in advancing hypothesis-driven research about dermatophytes.
Collapse
|
147
|
Fuchs BB, Bishop LR, Kovacs JA, Mylonakis E. Galleria mellonella are resistant to Pneumocystis murina infection. Mycopathologia 2010; 171:273-7. [PMID: 20922567 DOI: 10.1007/s11046-010-9368-4] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2010] [Accepted: 09/17/2010] [Indexed: 11/28/2022]
Abstract
Studying Pneumocystis has proven to be a challenge from the perspective of propagating a significant amount of the pathogen in a facile manner. The study of several fungal pathogens has been aided by the use of invertebrate model hosts. Our efforts to infect the invertebrate larvae Galleria mellonella with Pneumocystis proved futile since P. murina neither caused disease nor was able to proliferate within G. mellonella. It did, however, show that the pathogen could be rapidly cleared from the host.
Collapse
Affiliation(s)
- Beth Burgwyn Fuchs
- Division of Infectious Diseases, Massachusetts General Hospital, Gray-Jackson 504, 55 Fruit Street, Boston, MA 02114, USA.
| | | | | | | |
Collapse
|
148
|
Byruak A, Sribnaya O, Purygin P. Studying peptides of antibacterial fractions methods of the liquid chromatography and mass spectrometry. BIOMEDITSINSKAYA KHIMIYA 2010. [DOI: 10.18097/pbmc20105603387] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
The fractions containing antimicrobic peptides have been purified from a haemolymph of caterpillars Galleria mellonella by chromatographic methods and studied by mass spectrometry.
Collapse
Affiliation(s)
- A.K. Byruak
- Frumkin Institute of Physical Chemistry and electrochemistry
| | | | | |
Collapse
|
149
|
Abstract
In this work, the zebrafish model organism was developed to obtain a minivertebrate host system for a Candida albicans infection study. We demonstrated that C. albicans can colonize and invade zebrafish at multiple anatomical sites and kill the fish in a dose-dependent manner. Inside zebrafish, we monitored the progression of the C. albicans yeast-to-hypha transition by tracking morphogenesis, and we monitored the corresponding gene expression of the pathogen and the early host immune response. We performed a zebrafish survival assay with different C. albicans strains (SC5314, ATCC 10231, an hgc1 mutant, and a cph1/efg1 double mutant) to determine each strain's virulence, and the results were similar to findings reported in previous mouse model studies. Finally, using zebrafish embryos, we monitored C. albicans infection and visualized the interaction between pathogen and host myelomonocytic cells in vivo. Taken together, the results of this work demonstrate that zebrafish can be a useful host model to study C. albicans pathogenesis, and they highlight the advantages of using the zebrafish model in future invasive fungal research.
Collapse
|
150
|
Fuchs BB, Eby J, Nobile CJ, El Khoury JB, Mitchell AP, Mylonakis E. Role of filamentation in Galleria mellonella killing by Candida albicans. Microbes Infect 2010; 12:488-96. [PMID: 20223293 DOI: 10.1016/j.micinf.2010.03.001] [Citation(s) in RCA: 80] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2009] [Revised: 02/26/2010] [Accepted: 03/01/2010] [Indexed: 10/19/2022]
Abstract
Candida albicans is an important cause of morbidity in hospitalized and immunosuppressed patients. Virulence factors of C. albicans include: filamentation, proteinases, adherence proteins and biofilm formation. The objective of this work was to use Galleria mellonella as a model to study the roles of C. albicans filamentation in virulence. We focused our study to five genes BCR1, FLO8, KEM1, SUV3 and TEC1 that have been shown to play a role in filamentation. Filaments are necessary for biofilm formation and evading interaction with macrophages in mammalian infections. Among the five mutant strain tested, we found that only the flo8/flo8 mutant strain did not form filaments within G. mellonella. This strain also exhibited reduced virulence in the larvae. Another strain that exhibited reduced pathogenicity in the G. mellonella model was tec1/tec1 but by contrast, the tec1/tec1 strain retained the ability to form filaments. Overexpression of TEC1 in the flo8/flo8 mutant restored filamentation but did not restore virulence in the larvae as well as in a mouse model of C. albicans infection. The filamentation phenotype did not affect the ability of hemocytes, the immune cells of G. mellonella, to associate with the various mutant strains of C. albicans. The capacities of the tec1/tec1 mutant and the flo8/flo8 TDH3-TEC1 strains to form filaments with impaired virulence suggest that filamentation alone is not sufficient to kill G. mellonella and suggest other virulence factors may be associated with genes that regulate filamentation.
Collapse
Affiliation(s)
- Beth Burgwyn Fuchs
- Division of Infectious Disease, Massachusetts General Hospital, Boston, MA 02114, USA.
| | | | | | | | | | | |
Collapse
|