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Raval KM, Ghormade V, Rajamohanan PR, Choudhary H, Rudramurthy SM, Chakrabarti A, Paknikar K. Development of a nano-gold immunodiagnostic assay for rapid on-site detection of invasive aspergillosis. J Med Microbiol 2019; 68:1341-1352. [PMID: 31355743 DOI: 10.1099/jmm.0.001040] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Introduction. Timely detection of invasive aspergillosis (IA) caused by fungal pathogens, i.e. Aspergillus fumigatus and Aspergillus flavus, in immunocompromised patients is crucial in preventing high mortality.Aim. To develop a simple immunoassay for the detection of galactomannan (GM), an IA biomarker.Methodology. GM from A. fumigatus and A. flavus clinical strains was purified and characterized by X-ray diffraction, IR spectroscopy and 13C/1H nuclear magnetic resonance (NMR) for polyclonal antibody (pAb) production in rabbits. An enzyme-linked immunosorbent assay (ELISA) was standardized using concanavalin A to capture Aspergillus GM and pAbs to detect it. Gold nanoparticles (AuNPs) were synthesized and conjugated to pAbs for the development of a dot-blot immunoassay. The developed dot-blot was evaluated with 109 clinical serum and bronchoalveolar lavage samples.Results. Spectroscopy studies characterized the d-galactofuranosyl groups of GM responsible for the immune response and generation of pAbs. The ELISA employing pAbs showed a sensitivity of 1 ng ml-1 for Aspergillus GM. Furthermore, a sensitive, visual, rapid dot-blot assay developed by the conjugation of pAbs to AuNPs (~24±5 nm size, -36±2 mV zeta potential) had a detection limit of 1 pg ml-1 in serum. The pAbs interacted with Aspergillus spp. but did not cross-react with other fungal pathogen genera such as Penicillium and Candida. Evaluation of the dot-blot with 109 clinical samples showed high sensitivity (80 %) and specificity (93.2 %), with an overall assay accuracy of 89%.Conclusion. The developed nano-gold immunodiagnostic assay has immense potential for practical use in rapid, specific and sensitive on-site diagnosis of IA, even under resource-limited settings.
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Affiliation(s)
- Komal M Raval
- Savitribai Phule Pune University, Ganeshkhind, Pune 411007, India.,Nanobioscience Group, Agharkar Research Institute, Pune 411004, India
| | - Vandana Ghormade
- Nanobioscience Group, Agharkar Research Institute, Pune 411004, India.,Savitribai Phule Pune University, Ganeshkhind, Pune 411007, India
| | - P R Rajamohanan
- Central NMR Facility, National Chemical Laboratory, Pune 411008, India
| | - Hansraj Choudhary
- Department of Medical Microbiology, Postgraduate Institute of Medical Education and Research, Chandigarh 160012, India
| | - Shivaprakash M Rudramurthy
- Department of Medical Microbiology, Postgraduate Institute of Medical Education and Research, Chandigarh 160012, India
| | - Arunaloke Chakrabarti
- Department of Medical Microbiology, Postgraduate Institute of Medical Education and Research, Chandigarh 160012, India
| | - Kishore Paknikar
- Nanobioscience Group, Agharkar Research Institute, Pune 411004, India.,Savitribai Phule Pune University, Ganeshkhind, Pune 411007, India
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Conservation of Mannan Synthesis in Fungi of the Zygomycota and Ascomycota Reveals a Broad Diagnostic Target. mSphere 2018; 3:3/3/e00094-18. [PMID: 29720523 PMCID: PMC5932377 DOI: 10.1128/msphere.00094-18] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2018] [Accepted: 04/16/2018] [Indexed: 12/12/2022] Open
Abstract
Ascomycetes and zygomycetes account for the majority of (i) fungi responsible for cutaneous, subcutaneous, and invasive human fungal infections, (ii) plant fungal pathogens, (iii) fungi that threaten global biodiversity, (iv) fungal agents of agricultural spoilage, and (v) fungi in water-damaged buildings. Rapid recognition of fungal infection (or contamination) enables early treatment (or remediation). A bioinformatics search found homologues of Saccharomyces cerevisiae Mnn9p present in members of the Zygomycota and Ascomycota phyla and absent in members of the Chytridiomycota and Basidiomycota. Mnn9p is a component of the yeast mannan polymerization complex and is necessary for α-1,6 mannan production. A monoclonal antibody (2DA6) was produced that was reactive with purified mannans of Mucor, Rhizopus, Aspergillus, Fusarium, and Candida species. Experimentation using a 2DA6 antigen capture enzyme-linked immunosorbent assay (ELISA) and extracts of fungi from the four phyla found agreement between the presence or absence of Mnn9p homologues and production or lack of production of mannan reactive with 2DA6. Studies of cell extracts from yeast mannan mutants identified α-1,6 mannan as the epitope recognized by 2DA6. To translate this finding into a point-of-use diagnostic, a 2DA6 lateral flow immunoassay was constructed that detected mannan in (i) extracts of dermatophytes and fungi that produce trauma-related infection and (ii) tissue from plants infected with Grosmannia clavigera or Sclerotium cepivorum These studies (i) revealed that the conservation of α-1,6-linked mannan in fungi of the Zygomycota and Ascomycota can be exploited as a broad diagnostic target and (ii) have provided a means to detect that target in an immunoassay platform that is well suited for clinic or field use.IMPORTANCE A key question asked when faced with an infection, an infestation, or environmental damage is whether it is a fungus. Identification of fungi as the cause of the problem can lead to remediation or treatment. Zygomycetes and ascomycetes account for the vast majority of fungal causes of human, animal, and plant disease, large-scale biodiversity loss, agricultural spoilage, and contamination of water-damaged buildings. These studies revealed the conservation of a common cell wall structural component of zygomycetes and ascomycetes to be a diagnostic target applicable to multiple pathogenic fungi and have leveraged that insight for practical use. Monoclonal antibodies reactive with this pan-fungal structure were produced and used to construct immunoassays (including ELISA and lateral flow assay) for detection of a broad range of pathogenic fungi.
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Hall RA. Dressed to impress: impact of environmental adaptation on the Candida albicans cell wall. Mol Microbiol 2015; 97:7-17. [PMID: 25846717 PMCID: PMC4973840 DOI: 10.1111/mmi.13020] [Citation(s) in RCA: 48] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/31/2015] [Indexed: 11/27/2022]
Abstract
Candida albicans is an opportunistic fungal pathogen of humans causing superficial mucosal infections and life‐threatening systemic disease. The fungal cell wall is the first point of contact between the invading pathogen and the host innate immune system. As a result, the polysaccharides that comprise the cell wall act as pathogen associated molecular patterns, which govern the host–pathogen interaction. The cell wall is dynamic and responsive to changes in the external environment. Therefore, the host environment plays a critical role in regulating the host–pathogen interaction through modulation of the fungal cell wall. This review focuses on how environmental adaptation modulates the cell wall structure and composition, and the subsequent impact this has on the innate immune recognition of C. albicans.
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Affiliation(s)
- Rebecca A Hall
- School of Biosciences, Institute of Microbiology and Infection, University of Birmingham, Edgbaston Park Road, Birmingham, B15 2TT, UK
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Machová E, Fiačanová L, Čížová A, Korcová J. Mannoproteins from yeast and hyphal form of Candida albicans considerably differ in mannan and protein content. Carbohydr Res 2015; 408:12-7. [DOI: 10.1016/j.carres.2015.03.001] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2014] [Revised: 02/03/2015] [Accepted: 03/02/2015] [Indexed: 11/28/2022]
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Hall RA, Bates S, Lenardon MD, MacCallum DM, Wagener J, Lowman DW, Kruppa MD, Williams DL, Odds FC, Brown AJP, Gow NAR. The Mnn2 mannosyltransferase family modulates mannoprotein fibril length, immune recognition and virulence of Candida albicans. PLoS Pathog 2013; 9:e1003276. [PMID: 23633946 PMCID: PMC3636026 DOI: 10.1371/journal.ppat.1003276] [Citation(s) in RCA: 88] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2012] [Accepted: 02/06/2013] [Indexed: 11/19/2022] Open
Abstract
The fungal cell wall is the first point of interaction between an invading fungal pathogen and the host immune system. The outer layer of the cell wall is comprised of GPI anchored proteins, which are post-translationally modified by both N- and O-linked glycans. These glycans are important pathogen associated molecular patterns (PAMPs) recognised by the innate immune system. Glycan synthesis is mediated by a series of glycosyl transferases, located in the endoplasmic reticulum and Golgi apparatus. Mnn2 is responsible for the addition of the initial α1,2-mannose residue onto the α1,6-mannose backbone, forming the N-mannan outer chain branches. In Candida albicans, the MNN2 gene family is comprised of six members (MNN2, MNN21, MNN22, MNN23, MNN24 and MNN26). Using a series of single, double, triple, quintuple and sextuple mutants, we show, for the first time, that addition of α1,2-mannose is required for stabilisation of the α1,6-mannose backbone and hence regulates mannan fibril length. Sequential deletion of members of the MNN2 gene family resulted in the synthesis of lower molecular weight, less complex and more uniform N-glycans, with the sextuple mutant displaying only un-substituted α1,6-mannose. TEM images confirmed that the sextuple mutant was completely devoid of the outer mannan fibril layer, while deletion of two MNN2 orthologues resulted in short mannan fibrils. These changes in cell wall architecture correlated with decreased proinflammatory cytokine induction from monocytes and a decrease in fungal virulence in two animal models. Therefore, α1,2-mannose of N-mannan is important for both immune recognition and virulence of C. albicans.
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Affiliation(s)
- Rebecca A. Hall
- Aberdeen Fungal Group, Institute of Medical Sciences, University of Aberdeen, Foresterhill, Aberdeen, United Kingdom
| | - Steven Bates
- Biosciences, College of Life and Environmental Sciences, University of Exeter, Exeter, United Kingdom
| | - Megan D. Lenardon
- Aberdeen Fungal Group, Institute of Medical Sciences, University of Aberdeen, Foresterhill, Aberdeen, United Kingdom
| | - Donna M. MacCallum
- Aberdeen Fungal Group, Institute of Medical Sciences, University of Aberdeen, Foresterhill, Aberdeen, United Kingdom
| | - Jeanette Wagener
- Aberdeen Fungal Group, Institute of Medical Sciences, University of Aberdeen, Foresterhill, Aberdeen, United Kingdom
| | - Douglas W. Lowman
- Quillen College of Medicine, East Tennessee State University, Johnson City, Tennessee, United States of America
- AppRidge International, LLC, Telford, Tennessee, United States of America
| | - Michael D. Kruppa
- Quillen College of Medicine, East Tennessee State University, Johnson City, Tennessee, United States of America
| | - David L. Williams
- Quillen College of Medicine, East Tennessee State University, Johnson City, Tennessee, United States of America
| | - Frank C. Odds
- Aberdeen Fungal Group, Institute of Medical Sciences, University of Aberdeen, Foresterhill, Aberdeen, United Kingdom
| | - Alistair J. P. Brown
- Aberdeen Fungal Group, Institute of Medical Sciences, University of Aberdeen, Foresterhill, Aberdeen, United Kingdom
| | - Neil A. R. Gow
- Aberdeen Fungal Group, Institute of Medical Sciences, University of Aberdeen, Foresterhill, Aberdeen, United Kingdom
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Kobayashi H, Kawakami S, Ogawa Y, Shibata N, Suzuki S. Isolation of Mannooligosaccharides Corresponding to Antigenic Determinants of Pathogenic Yeast <i>Candida catenulata</i> Cell Wall Mannan. ACTA ACUST UNITED AC 2013. [DOI: 10.4236/aim.2013.32033] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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7
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Kobayashi H, Kawakami S, Ogawa Y, Shibata N, Suzuki S. Structural Investigation of Cell Wall Mannan Antigen Obtained from Pathogenic Yeast <i>Candida zeylanoides</i>. ACTA ACUST UNITED AC 2013. [DOI: 10.4236/ojmm.2013.32021] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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8
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Binding of DC-SIGN to glycoproteins expressed in glycoengineered Pichia pastoris. J Immunol Methods 2012; 386:34-42. [DOI: 10.1016/j.jim.2012.08.015] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2012] [Revised: 08/24/2012] [Accepted: 08/28/2012] [Indexed: 11/23/2022]
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9
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Johnson MA, Cartmell J, Weisser NE, Woods RJ, Bundle DR. Molecular recognition of Candida albicans (1->2)-β-mannan oligosaccharides by a protective monoclonal antibody reveals the immunodominance of internal saccharide residues. J Biol Chem 2012; 287:18078-90. [PMID: 22493450 DOI: 10.1074/jbc.m112.355578] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
A self-consistent model of β-mannan oligosaccharides bound to a monoclonal antibody, C3.1, that protects mice against Candida albicans has been developed through chemical mapping, NMR spectroscopic, and computational studies. This antibody optimally binds di- and trisaccharide epitopes, whereas larger oligomers bind with affinities that markedly decrease with increasing chain length. The (1→2)-β-linked di-, tri-, and tetramannosides bind in helical conformations similar to the solution global minimum. Antibody recognition of the di- and trisaccharide is primarily dependent on the mannose unit at the reducing end, with the hydrophobic face of this sugar being tightly bound. Recognition of a tetrasaccharide involves a frameshift in the ligand interaction, shown by strong binding of the sugar adjacent to the reducing end. We show that frameshifting may also be deliberately induced by chemical modifications. Molecular recognition patterns similar to that of mAb C3.1, determined by saturation transfer difference-NMR, were also observed in polyclonal sera from rabbits immunized with a trisaccharide glycoconjugate. The latter observation points to the importance of internal residues as immunodominant epitopes in (1→2)-β-mannans and to the viability of a glycoconjugate vaccine composed of a minimal length oligosaccharide hapten.
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Affiliation(s)
- Margaret A Johnson
- Department of Chemistry, University of Alberta, Edmonton, Alberta, Canada.
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Difference in fine specificity to polysaccharides of Candida albicans mannoprotein between mouse SIGNR1 and human DC-SIGN. Infect Immun 2012; 80:1699-706. [PMID: 22331432 DOI: 10.1128/iai.06308-11] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
C-type lectin SIGNR1 directly recognizes Candida albicans and zymosan and has been considered to share properties of polysaccharide recognition with human DC-SIGN (hDC-SIGN). However, the precise specificity of SIGNR1 and the difference from that of hDC-SIGN remain to be elucidated. We prepared soluble forms of SIGNR1 and hDC-SIGN and conducted experiments to examine their respective specificities. Soluble SIGNR1 (sSIGNR1) bound several types of live C. albicans clinical isolate strains in an EDTA-sensitive manner. Inhibition analyses of sSIGNR1 binding by glycans from various yeast strains demonstrated that SIGNR1 preferentially recognizes N-glycan α-mannose side chains in Candida mannoproteins, as reported in hDC-SIGN. Unlike shDC-SIGN, however, sSIGNR1 recognized not only Saccharomyces cerevisiae, but also C. albicans J-1012 glycan, even after α-mannosidase treatment that leaves only β1,2-mannose-capped α-mannose side chains. In addition, glycomicroarray analyses showed that sSIGNR1 binds mannans from C. albicans and S. cerevisiae but does not recognize Lewis(a/b/x/y) antigen polysaccharides as in shDC-SIGN. Consistent with these results, RAW264.7 cells expressing hDC-SIGN in which the carbohydrate recognition domain (CRD) was replaced with that of SIGNR1 (RAW-chimera) produced comparable amounts of interleukin 10 (IL-10) in response to glycans from C. albicans and S. cerevisiae, but those expressing hDC-SIGN produced less IL-10 in response to S. cerevisiae than C. albicans. Furthermore, RAW-hDC-SIGN cells remarkably reduced IL-10 production after α-mannosidase treatment compared with RAW-chimera cells. These results indicate that SIGNR1 recognizes C. albicans/yeast through a specificity partly distinct from that of its homologue hDC-SIGN.
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Mannan structural complexity is decreased when Candida albicans is cultivated in blood or serum at physiological temperature. Carbohydr Res 2011; 346:2752-9. [PMID: 22030461 DOI: 10.1016/j.carres.2011.09.029] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2011] [Revised: 09/19/2011] [Accepted: 09/24/2011] [Indexed: 11/20/2022]
Abstract
The Candida albicans cell wall provides an architecture that allows for the organism to survive environmental stress as well as interaction with host tissues. Previous work has focused on growing C. albicans on media such as Sabouraud or YPD at 30°C. Because C. albicans normally colonizes a host, we hypothesized that cultivation on blood or serum at 37°C would result in structural changes in cell wall mannan. C. albicans SC5314 was inoculated onto YPD, 5% blood, or 5% serum agar media three successive times at 30°C and 37°C, then cultivated overnight at 30°C in YPD. The mannan was extracted and characterized using 1D and 2D (1)H NMR techniques. At 30°C cells grown in blood and serum contain less acid-stable terminal β-(1→2)-linked d-mannose and α-(1→2)-linked d-mannose-containing side chains, while the acid-labile side chains of mannan grown in blood and serum contain fewer β-Man-(1→2)-α-Man-(1→ side chains. The decrement in acid-stable mannan side chains is greater at 37°C than at 30°C. Cells grown on blood at 37°C show fewer →6)-α-Man-(1→ structural motifs in the acid-stable polymer backbone. The data indicate that C. albicans, grown on media containing host-derived components, produces less complex mannan. This is accentuated when the cells are cultured at 37°C. This study demonstrates that the C. albicans cell wall is a dynamic and adaptive organelle, which alters its structural phenotype in response to growth in host-derived media at physiological temperature.
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Kruppa M, Greene RR, Noss I, Lowman DW, Williams DL. C. albicans increases cell wall mannoprotein, but not mannan, in response to blood, serum and cultivation at physiological temperature. Glycobiology 2011; 21:1173-80. [PMID: 21515585 DOI: 10.1093/glycob/cwr051] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
The cell wall of Candida albicans is central to the yeasts ability to withstand osmotic challenge, to adhere to host cells, to interact with the innate immune system and ultimately to the virulence of the organism. Little is known about the effect of culture conditions on the cell wall structure and composition of C. albicans. We examined the effect of different media and culture temperatures on the molecular weight (Mw), polymer distribution and composition of cell wall mannan and mannoprotein complex. Strain SC5314 was inoculated from frozen stock onto yeast peptone dextrose (YPD), blood or 5% serum agar media at 30 or 37°C prior to mannan/mannoprotein extraction. Cultivation of the yeast in blood or serum at physiologic temperature resulted in an additive effect on Mw, however, cultivation media had the greatest impact on Mw. Mannan from a yeast grown on blood or serum at 30°C showed a 38.9 and 28.6% increase in Mw, when compared with mannan from YPD-grown yeast at 30°C. Mannan from the yeast pregrown on blood or serum at 37°C showed increased Mw (8.8 and 26.3%) when compared with YPD mannan at 37°C. The changes in Mw over the entire polymer distribution were due to an increase in the amount of mannoprotein (23.8-100%) and a decrease in cell wall mannan (5.7-17.3%). We conclude that C. albicans alters the composition of its cell wall, and thus its phenotype, in response to cultivation in blood, serum and/or physiologic temperature by increasing the amount of the mannoprotein and decreasing the amount of the mannan in the cell wall.
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Affiliation(s)
- Michael Kruppa
- Department of Microbiology, Quillen College of Medicine, East Tennessee State University, Johnson City, TN 37614, USA.
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Kuma H, Oyamada H, Tsukamoto A, Mizoguchi T, Kandori A, Sugiura Y, Yoshinaga K, Enpuku K, Hamasaki N. Liquid phase immunoassays utilizing magnetic markers and SQUID magnetometer. Clin Chem Lab Med 2011; 48:1263-9. [PMID: 20678032 DOI: 10.1515/cclm.2010.259] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
BACKGROUND Immunoassays are one main detection system used in the field of clinical chemistry. Recent developments of a new detection method utilizing a magnetic marker and magnetic sensor have enabled rapid and sensitive immunoassay without the need for bound/free (BF) separation. METHODS Newly-synthesized conjugated avidin was used as the magnetic marker for quantitative analysis of human interleukin-8 (hIL-8) and immunoglobulin E (hIgE) in several media. A superconducting quantum interference device sensor detected the magnetic fields from markers fixed to antigens by the sandwich method. Magnetic signals from unbound markers were nearly zero due to Brownian rotation. RESULTS Our magnetic immunoassay could detect four attomoles of model proteins (hIL-8, hIgE) in phosphate buffer without BF separation. Using our standard curve, the range of protein detected ranged from 40 femtomoles to 4 attomoles, and we observed a strong association between protein amounts and magnetic signals from the bound markers. The homogeneous immunoassay could also quantify three hundred cells from the fungus Candida albicans in phosphate buffer. CONCLUSIONS The present study demonstrates the ability of magnetic markers for measuring biological targets without BF separation. This detection system has great potential for use as the next generation's analytical system.
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Affiliation(s)
- Hiroyuki Kuma
- Department of Clinical Chemistry and Laboratory Medicine, Faculty of Pharmaceutical Sciences, Nagasaki International University, Sasebo, Japan.
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Dectin-2 Recognition of α-Mannans and Induction of Th17 Cell Differentiation Is Essential for Host Defense against Candida albicans. Immunity 2010; 32:681-91. [DOI: 10.1016/j.immuni.2010.05.001] [Citation(s) in RCA: 559] [Impact Index Per Article: 39.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2009] [Revised: 02/19/2010] [Accepted: 05/03/2010] [Indexed: 11/24/2022]
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Ekholm FS, Sinkkonen J, Leino R. Fully deprotected β-(1→2)-mannotetraose forms a contorted α-helix in solution: convergent synthesis and conformational characterization by NMR and DFT. NEW J CHEM 2010. [DOI: 10.1039/b9nj00702d] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Model alpha-mannoside conjugates: immunogenicity and induction of candidacidal activity. ACTA ACUST UNITED AC 2009; 58:307-13. [PMID: 20113351 DOI: 10.1111/j.1574-695x.2009.00642.x] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
The effect of Candida cell wall mannan-derived alpha-oligomannoside structural components on the modulation of the immune system and their role in protective immunity are studied here. Semi-synthetic alpha-mannoside-bovine serum albumin conjugates were used for immunization of rabbits. Dimeric alpha-mannoside, representing Candida antigenic factor 1, was used as a model of linear alpha-mannoside, and pentameric alpha-mannoside was used as a model of branched oligomannoside side chain structure. The induction of humoral immune response and the functionality of the serum tested by induction of peripheral blood leukocyte (PBL) candidacidal activity are documented. Anti-Candida albicans serotype B immunoglobulins (IgG and IgM) levels were higher than anti-serotype A following immunization with both conjugates. Dimer-conjugate postimmunization sera evidently enhanced C. albicans killing activity of PBLs in candidacidal assay. The study shows the importance of alpha-mannoside structures in perspective anti-Candida vaccine with a broad spectrum of effectiveness.
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Goto K, Suzuki A, Shibata N, Okawa Y. Some properties of beta-1,2-mannosyltransferases related to the biosynthesis of the acid-labile oligomannosyl side chains in Candida albicans NIH B-792 strain cells. Biol Pharm Bull 2009; 32:1921-3. [PMID: 19881309 DOI: 10.1248/bpb.32.1921] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
We detected the beta-1,2-mannosyltransferases (beta-1,2-MTs), which participate in the biosynthesis of oligomannosyl side chains in the mannan acid-labile fraction, in a particulate insoluble fractions prepared from Candida albicans NIH B-792 strain cells grown at 27 degrees C and at 37 degrees C in a yeast extract-added Sabouraud liquid medium (YSLM). The beta-1,2-MT VI-6 prepared from the cells grown at 27 degrees C exhibited the maximum activity at pH 7.0 and at 30 degrees C. The beta-1,2-MT VI-6 activity was only slightly affected by Mn2+, Mg2+, Ca2+, and ethylenediaminetetraacetic acid, but completely inhibited by Zn2+ and Ni2+. The beta-1,2-MT activities from the cells grown at 37 degrees C were lower than that from the cells grown at 27 degrees C, especially on the longer beta-1,2-mannooligosaccharides than tetraose.
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Affiliation(s)
- Kouji Goto
- Department of Infection and Host Defense, Tohoku Pharmaceutical University, Komatsushima, Aoba-ku, Sendai, Miyagi 981-8558, Japan
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Koyama T, Makita M, Shibata N, Okawa Y. Influence of oxidative and osmotic stresses on the structure of the cell wall mannan of Candida albicans serotype A. Carbohydr Res 2009; 344:2195-200. [DOI: 10.1016/j.carres.2009.08.002] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2008] [Revised: 07/08/2009] [Accepted: 08/01/2009] [Indexed: 11/25/2022]
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Barnay-Verdier S, Beckerich JM, Boisramé A. New components of Yarrowia lipolytica Golgi multi-protein complexes containing the α-1,6-mannosyltransferases YlMnn9p and YlAnl1p. Curr Genet 2008; 54:313-23. [DOI: 10.1007/s00294-008-0219-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2008] [Revised: 10/13/2008] [Accepted: 10/13/2008] [Indexed: 10/21/2022]
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Karelin AA, Tsvetkov YE, Paulovicová L, Bystrický S, Paulovicová E, Nifantiev NE. Synthesis of a heptasaccharide fragment of the mannan from Candida guilliermondii cell wall and its conjugate with BSA. Carbohydr Res 2008; 344:29-35. [PMID: 18976984 DOI: 10.1016/j.carres.2008.09.016] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2008] [Revised: 09/06/2008] [Accepted: 09/17/2008] [Indexed: 11/25/2022]
Abstract
The 3-aminopropyl glycoside of a heptasaccharide fragment of the cell wall mannan from Candida guilliermondii 18, which corresponds to the antigenic Factor 9, has been synthesized by a convergent approach based on glycosylation of a tetrasaccharide acceptor with a trisaccharide donor as the key step to give a protected heptasaccharide 17. Subsequent two-step deprotection of 17 afforded the heptamannoside 18, which was then conjugated with BSA using the squarate procedure.
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Affiliation(s)
- Alexander A Karelin
- Laboratory of Glycoconjugate Chemistry, N. D. Zelinsky Institute of Organic Chemistry, Russian Academy of Sciences, Leninsky prospect 47, 119991 Moscow, Russia
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Beta-1,2 oligomannose adhesin epitopes are widely distributed over the different families of Candida albicans cell wall mannoproteins and are associated through both N- and O-glycosylation processes. Infect Immun 2008; 76:4509-17. [PMID: 18644880 DOI: 10.1128/iai.00368-08] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
Beta-1,2-linked mannosides (beta-Mans) are believed to contribute to Candida albicans virulence. The presence of beta-Mans has been chemically established for two molecules (phosphopeptidomannan [PPM] and phospholipomannan) that are noncovalently linked to the cell wall, where they correspond to specific epitopes. However, a large number of cell wall mannoproteins (CWMPs) also express beta-Man epitopes, although their nature and mode of beta-mannosylation are unknown. We therefore used Western blotting to map beta-Man epitopes for the different families of mannoproteins gradually released from the cell wall according to their mode of anchorage (soluble, released by dithiothreitol, beta-1,3 glucan linked, and beta-1,6 glucan linked). Reduction of beta-Man epitope expression occurred after chemical and enzymatic deglycosylation of the different cell wall fractions, as well as in a secreted form of Hwp1, a representative of the CWMPs linked by glycosylphosphatidylinositol remnants. Enzyme-linked immunosorbent assay inhibition tests were performed to assess the presence of beta-Man epitopes in released oligomannosides. A comparison of the results obtained with CWMPs to the results obtained with PPM and the use of mutants with mutations affecting O and N glycosylation demonstrated that both O glycosylation and N glycosylation participate in the association of beta-Mans with the protein moieties of CWMPs. This process, which can alter the function of cell wall molecules and their recognition by the host, is therefore more important and more complex than originally thought, since it differs from the model established previously with PPM.
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Oyamada H, Ogawa Y, Shibata N, Okawa Y, Suzuki S, Kobayashi H. Structural analysis of cell wall mannan of Candida sojae, a new yeast species isolated from defatted soybean flakes. Arch Microbiol 2008; 189:483-90. [PMID: 18084740 DOI: 10.1007/s00203-007-0339-1] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2007] [Revised: 11/26/2007] [Accepted: 11/26/2007] [Indexed: 10/22/2022]
Abstract
We investigated the structural and immunochemical characteristics of cell wall mannan obtained from Candida sojae JCM 1644, which is a new yeast species isolated from defatted soybean flakes. The results of a slide-agglutination test and of an enzyme-linked immunosorbent assay using anti-factor sera to the pathogenic Candida species indicated that the cells and the C. sojae mannan were cross-reactive to the specific anti-factor sera against Candida albicans serotype A (FAb 6) and Candida guilliermondii (FAb 9). Two-dimensional homonuclear Hartmann-Hahn analysis indicated that the mannan consisted of various linked oligomannosyl side chains containing alpha-1,2-, alpha-1,3-, alpha-1,6- and beta-1,2-linked mannose residues. However, although the determinants of antigenic factors 6 and 9 could be not found in this mannan, branched side chains, Manbeta1-2Manalpha1-3[Manalpha1-6]Manalpha1-(2Manalpha1-)n2Man and a linear alpha-1,6-linked polymannosyl backbone, which are cross-reacted by FAbs 6 and 9, respectively, were identified. The mannan was subjected to acetolysis in order to determine the polymerization length of the alpha-1,2-linked oligomannosyl residue in the side chains. The result of (1)H-nuclear magnetic resonance analysis of the released oligosaccharides showed that the remarkable regularity in the length of alpha-1,2-linked oligomannosyl side chains, which were previously found in mannans of other Candida species, is not observed in this mannan.
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Affiliation(s)
- Hiroko Oyamada
- Department of Microbiology, Nagasaki International University, 2825-7 Huis Ten Bosch, Sasebo, Nagasaki, Japan
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23
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Goto K, Okawa Y. Activity and Stability of .ALPHA.- and .BETA.-Mannosyltransferases in Candida albicans Cells Cultured at High Temperature and at Low pH. Biol Pharm Bull 2008; 31:1333-6. [DOI: 10.1248/bpb.31.1333] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Affiliation(s)
- Kouji Goto
- Department of Infection and Host Defense, Tohoku Pharmaceutical University; 4–4&ndash
| | - Yoshio Okawa
- Department of Infection and Host Defense, Tohoku Pharmaceutical University; 4–4&ndash
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Human pathogen Candida dubliniensis: A cell wall mannan with a high content of β-1,2-linked mannose residues. Carbohydr Polym 2007. [DOI: 10.1016/j.carbpol.2007.03.007] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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Hazen KC, Singleton DR, Masuoka J. Influence of outer region mannosylphosphorylation on N-glycan formation by Candida albicans: normal acid-stable N-glycan formation requires acid-labile mannosylphosphate addition. Glycobiology 2007; 17:1052-60. [PMID: 17670843 DOI: 10.1093/glycob/cwm080] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
The pathogenic yeast Candida albicans produces large N-glycans with outer regions containing only mannose residues. The outer region comprises a primary branch with multiple secondary and tertiary branches. Tertiary branches are linked to secondary branches by phosphodiester bridges. In the current model of outer chain elongation in the genetically related yeast Saccharomyces cerevisiae, synthesis of the branches occurs sequentially, primary to tertiary. Thus, disruption of mannosylphosphorylation, the initial step in tertiary branch formation, should not affect primary or secondary branch production. Compared to its wild-type parent, a C. albicans mutant defective in tertiary branch mannosylphosphorylation (mnn4Delta/mnn4Delta) made outer regions with reduced susceptibility to low acid acetolysis treatment, suggesting that the secondary or primary region had been modified. Higher acid acetolysis conditions were required to release the secondary branches from the primary branches. The released secondary branches constitute the subset of the wild-type secondary branches that lack a phosphate group. In contrast, the acid-stable region of both wild-type and mnn4Delta S. cerevisiae strains required high acid acetolysis conditions to release the secondary branches, despite having smaller and less complex secondary and tertiary branches. These results suggest that the complex and longer secondary and tertiary branches of C. albicans affect the conformation of the acid-stable region to render it more susceptible to acetolysis which implies secondary and tertiary branch formation in C. albicans are interdependent events and occur concurrently, rather than sequentially.
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Affiliation(s)
- Kevin C Hazen
- Department of Pathology, University of Virginia Health Center, Charlottesville, VA 22908-0904, USA.
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Shibata N, Suzuki A, Kobayashi H, Okawa Y. Chemical structure of the cell-wall mannan of Candida albicans serotype A and its difference in yeast and hyphal forms. Biochem J 2007; 404:365-72. [PMID: 17331070 PMCID: PMC1896289 DOI: 10.1042/bj20070081] [Citation(s) in RCA: 129] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
The structure of the cell-wall mannan from the J-1012 (serotype A) strain of the polymorphic yeast Candida albicans was determined by acetolysis under mild conditions followed by HPLC and sequential NMR experiments. The serotype A mannan contained beta-1,2-linked mannose residues attached to alpha-1,3-linked mannose residues and alpha-1,6-linked branching mannose residues. Using a beta-1,2-mannosyltransferase, we synthesized a three-beta-1,2-linkage-containing mannoheptaose and used it as a reference oligosaccharide for 1H-NMR assignment. On the basis of the results obtained, we derived an additivity rule for the 1H-NMR chemical shifts of the beta-1,2-linked mannose residues. The morphological transformation of Candida cells from the yeast form to the hyphal form induced a significant decrease in the phosphodiesterified acid-labile beta-1,2-linked manno-oligosaccharides, whereas the amount of acid-stable beta-1,2 linkage-containing side chains did not change. These results suggest that the Candida mannan in candidiasis patients contains beta-1,2-linked mannose residues and that they behave as a target of the immune system.
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Affiliation(s)
- Nobuyuki Shibata
- Department of Infection and Host Defense, Tohoku Pharmaceutical University, Sendai, Miyagi 981-8558, Japan.
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Abstract
All cells of four Candida tropicalis strains IFO 0199 (Ct-0199), IFO 0587 (Ct-0587), IFO 1400 (Ct-1400), and IFO 1647 (Ct-1647), obtained by cultivation at 27 and 37 degrees C for 48 h in yeast extract-added Sabouraud liquid medium, showed the shapes of typical budding yeast and the same agglutination patterns against factor sera 1, 4, 5 and 6 in the commercially available kit 'Candida Check'. The cells of the C. tropicalis IFO 0589 strain display the same properties at 27 degrees C but formed hyphae at 37 degrees C. The cell wall mannan (Ct-0589-37-M) obtained from the strain cells cultured at 37 degrees C had lost most of its reactivity against factor sera 4, 5 and 6 in an enzyme-linked immunosorbent assay, in contrast to the mannan (Ct-0589-27-M) at 27 degrees C. The 1H-nuclear magnetic resonance patterns of the mannans obtained from the cells of the four C. tropicalis strains IFO 0199, IFO 0587, IFO 1400, and IFO 1647, obtained by cultivation at 37 degrees C, did not change compared to those at 27 degrees C. By contrast, the Ct-0589-37-M had significantly lost the beta-1,2-linked mannopyranose units, corresponding to the serum factors 5 and 6. These results show that the IFO 0589 strain is an unusual strain among the general C. tropicalis strains studied.
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Affiliation(s)
- Yoshio Okawa
- Second Department of Hygienic Chemistry, Tohoku Pharmaceutical University, Sendai, Miyagi, Japan.
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Okawa Y, Goto K. Disappearance of antigenic factor 6 in Candida glabrata IFO 0622 strain cells cultured at high temperature. Biol Pharm Bull 2006; 29:187-9. [PMID: 16394538 DOI: 10.1248/bpb.29.187] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The Candida glabrata IFO 0622 strain cells obtained after cultivation at 27 degrees C and at 37 degrees C and then at 27 degrees C (37-27 degrees C) for 48 h in yeast extract-added Sabouraud liquid medium (YSLM) showed the same agglutination patterns against factor sera 1, 4, 6, and 34 in the commercially available factor serum kit 'Candida Check'. On the other hand, the cells of the strain cultured at 37 degrees C had completely lost its reactivity against the factor serum 6. The enzyme-linked immunosorbent assay (ELISA) of the cell wall mannans obtained from the strain cells showed the same reactivity with the agglutination patterns against the factor sera. The 1H-nuclear magnetic resonance (NMR) pattern of the mannan obtained from the strain cells cultured at 37 degrees C showed that the mannan had completely lost the non-reducing beta-1,2-linked mannopyranose unit in the mannotetraose Manbeta1-2Manalpha1-2Manalpha1-2Man, corresponding to the serum factor 6.
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Affiliation(s)
- Yoshio Okawa
- Second Department of Hygienic Chemistry, Tohoku Pharmaceutical University, Miyagi, Japan.
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Okawa Y, Oikawa S, Suzuki S. Structural changes of cell wall mannans of Candida guilliermondii IFO 10279 strain cells cultured at high temperature. Biol Pharm Bull 2006; 29:388-91. [PMID: 16462053 DOI: 10.1248/bpb.29.388] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The morphology, structure, and antigenicity of the cells and the cell wall mannans of the Candida guilliermondii IFO 10279 strain cultivated at 33 and 34 degrees C for 48 h in yeast extract-added Sabouraud liquid medium (YSLM) were compared with those cultivated at 27 degrees C and 33 degrees C and then at 27 degrees C (33-27 degrees C). This strain showed little growth at higher than 35 degrees C. The density of the yeast formed cells decreased, with dry weights of about 50% at 33 and 34 degrees C, and only the cells at 34 degrees C revealed a failure of cytokinesis. The structure of the mannans revealed by (1)H-NMR analysis that the mannans obtained at both 33 and 34 degrees C had drastically decreased two consecutive beta-1,2-linked mannopyranose units at the nonreducing terminal of the alpha-linked oligosaccharides and increased one beta-1,2-linked mannopyranose unit at the nonreducing terminal attached to the alpha-1,3-linked mannose unit and the non-reducing terminal alpha-1,3- and alpha-1,2-linked mannopyranose units. The enzyme-linked immunosorbent assay (ELISA) showed that the mannans obtained at 33 and 34 degrees C had decreased reactivity against the factor serum 9 and increased its reactivity against the factor serum 4, in the commercially available factor serum kit "Candida Check".
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Affiliation(s)
- Yoshio Okawa
- Second Department of Hygienic Chemistry, Tohoku Pharmaceutical University, 4-4-1 Komatsushima, Aoba-ku, Sendai, Miyagi 981-8558, Japan.
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Kobayashi H, Tanaka S, Suzuki J, Kiuchi Y, Shibata N, Suzuki S, Okawa Y. Amended structure of side chains in a cell wall mannan from Candida albicans serotype A strain grown in yeast extract-Sabouraud liquid medium under acidic conditions: detection of the branched side chains corresponding to antigenic factor 4. FEMS Microbiol Lett 2006. [DOI: 10.1111/j.1574-6968.1997.tb10433.x] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
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Zhang MX, Bohlman MC, Itatani C, Burton DR, Parren PWHI, St Jeor SC, Kozel TR. Human recombinant antimannan immunoglobulin G1 antibody confers resistance to hematogenously disseminated candidiasis in mice. Infect Immun 2006; 74:362-9. [PMID: 16368991 PMCID: PMC1346657 DOI: 10.1128/iai.74.1.362-369.2006] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2005] [Revised: 09/21/2005] [Accepted: 10/08/2005] [Indexed: 11/20/2022] Open
Abstract
Mannan is a major cell wall component found in Candida species. Natural antimannan antibody is present in sera from most normal adults, but its role in host resistance to hematogenously disseminated candidiasis is unknown. The purpose of this study was to develop recombinant human antimannan antibody and to study its protective function. A phage Fab display combinatorial library containing Fab genes from bone marrow lymphocytes was screened with Candida albicans yeast cells and chemically purified mannan. One antimannan Fab, termed M1, was converted to a full-length immunoglobulin G1 antibody, M1g1, and M1g1 was produced in CHO cells. The M1g1 epitope was found in C. albicans serotypes A and B, Candida tropicalis, Candida guilliermondii, Candida glabrata, and Candida parapsilosis. Its expression was active at both 23 degrees C and 37 degrees C and uniform over the cell surface. BALB/c mice passively immunized with M1g1 were more resistant than control mice to a lethal hematogenous infection by C. albicans, as evidenced by extension of survival in an M1g1 dose-dependent manner (P, 0.08 to <0.001) and by reduction in number of infection foci and their size in the kidney. In vitro studies found that M1g1 promoted phagocytosis and phagocytic killing of C. albicans yeast cells by mouse peritoneal macrophages and was required for activation of the mouse complement cascade. Thus, human antimannan antibody may have a protective role in host resistance to systemic candidiasis.
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Affiliation(s)
- Mason X Zhang
- Department of Biological Sciences, California State University-Long Beach, 1250 Bellflower Boulevard, Long Beach, CA 90840, USA.
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Okawa Y, Goto K. Antigenicity of Cell Wall Mannans of Candida albicans and Candida stellatoidea Cultured at High Temperatures in BACTEC Medium. Biol Pharm Bull 2006; 29:1723-7. [PMID: 16880632 DOI: 10.1248/bpb.29.1723] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The study of the antigenicity of pathogenic Candida albicans and Candida stellatoidea cells grown in BACTEC fungal medium (BFM) is useful for clinical analysis so as accurately to diagnose candidiasis. When C. albicans NIH A-207 was grown in BFM and fetal bovine serum-added BFM at the high temperatures of 36 and 40 degrees C, the cell density increased, with a mixture of yeast cells, pseudohyphae, and hyphae and with full hyphal development in the cultures compared with cultivation (mostly cells in yeast form) at 27 degrees C in both media. The mannans produced when cells were grown at these high temperatures were less reactive by enzyme-linked immunosorbent assay with factor sera 4, 5, and 6 in the commercially available kit 'Candida Check' than were the mannans obtained following growth at 27 degrees C. Based on 1H-nuclear magnetic resonance analysis, the mannans from cells grown at high temperatures had lost a phosphate group and a beta-1,2-linked mannopyranose unit, and had increased the number of non-reducing terminal alpha-1,3-linked mannopyranose units. We obtained similar results for mannans produced by C. albicans J-1012, C. albicans NIH B-792, C. albicans JCM 9061, C. stellatoidea ATCC 20408, and C. stellatoidea ATCC 36232 strains cultivated in BFM at 36 degrees C. These results suggest that both C. albicans and C. stellatoidea cells cultured at high temperatures, irrespective of the medium and shape of the cells, alter their antigenicity and chemical structure of cell wall mannans.
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Affiliation(s)
- Yoshio Okawa
- Department of Infection and Host Defense, Tohoku Pharmaceutical University, Japan.
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Okawa Y, Miyauchi M, Goto K, Giummelly P. Antigenicity of cell wall mannans of Candida albicans NIH A-207 strain cells cultured in galactose-added yeast nitrogen base medium. Biol Pharm Bull 2005; 28:391-3. [PMID: 15684509 DOI: 10.1248/bpb.28.391] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The cultivations of the Candida albicans NIH A-207 strain (A-strain) for 5 d at 27 and 37 degrees C in 500 mM galactose-added yeast nitrogen base medium (YNB-Gal) decreased the growth of blastoconidia and the pH in the cultures, with dry weights of 56 and 47% and with pHs of 2.41 and 2.47, compared with the dry weight of 100% and pH of 5.63 for a standard cultivation of 2 d at 27 degrees C in the yeast extract-added Sabouraud liquid medium (YSLM). The cells obtained by cultivations at 27 and 37 degrees C in the YNB-Gal clearly decreased the agglutination against serum factors 4, 5, and 6 in the commercially available kit 'Candida Check', especially at 37 degrees C, in contrast to those obtained by the standard cultivation. It was also revealed by 1H-NMR analysis that both the mannans obtained from cultures at 27 and 37 degrees C in the YNB-Gal had drastically lost a phosphate group and a beta-1,2-linked mannopyranose unit, and increased the non-reducing terminal alpha-1,3-linked mannopyranose unit, especially at 37 degrees C.
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Affiliation(s)
- Yoshio Okawa
- Second Department of Hygienic Chemistry, Tohoku Pharmaceutical University, 4-4-1 Komatsushima, Aoba-ku, Sendai, Miyagi 981-8558, Japan.
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Tansho S, Abe S, Ishibashi H, Mitsuya M, Wada K, Ikeda T, Suegara N, Koshio O, Ono Y, Yamaguchi H. Production of anti-Candida antibodies in mice with gut colonization of Candida albicans. Mediators Inflamm 2005; 13:189-93. [PMID: 15223610 PMCID: PMC1781562 DOI: 10.1080/09511920410001713510] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
BACKGROUND: Production of antibodies that are specific for allergens is an important pathological process in inflammatory allergic diseases. These contain the antibodies against antigens of Candida albicans, one of the normal microbial flora in an intestinal tract. We studied the effects of the prednisolone administration on the production of anti-Candida antibodies in the gastrointestinally C. albicans-colonized mice. METHODS AND MATERIALS: BALB/c mice, treated with antibacterial antibiotics to decontaminate indigenous intestinal bacterial flora, were inoculated intragastrically with C. albicans. The mice, in which C. albicans grows intestinally, were administered prednisolone to induce temporary immunosuppression. The Candida growth in their intestinal tract and their antibody response to Candida were examined. RESULTS: Antibiotic treatment allowed establishment of C. albicans gastrointestinal colonization, but did not cause subsequent systemic dissemination of C. albicans in all the animals. When these animals received an additional treatment with prednisolone, they showed a significantly higher population of C. albicans in their feces than those of animals treated with antibiotics alone, and the organisms were recovered even from their kidney. This systemic dissemination by C. albicans appeared to be temporal, because all the mice survived without any symptoms for more than 2 months. Examination of the serum titers of total immunoglobulin (Ig)E antibodies and specific IgE and IgG antibodies against Candida antigens demonstrated that titers of total IgE increased, partially by day 14 and clearly at day 27, in prednisolone-treated Candida-colonized mice. Without prednisolone treatment, an increment of the serum titer was scarcely observed. By day 27, corresponding to the increase of total IgE, the anti-Candida IgE and IgG titer increased in mice of the prednisolone-treated group. CONCLUSION: Administration of prednisolone to Candida-colonized mice can induce production of the IgG, IgE antibodies against Candida antigens, perhaps through temporal systemic dissemination of Candida from the intestinal tract.
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Affiliation(s)
- Shigeru Tansho
- Department of Microbiology and Immunology, Teikyo University School of Medicine, 2-11-1 kaga Itabashi-ku, Tokyo 173-8605, Japan.
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Masuoka J, Hazen KC. Cell wall mannan and cell surface hydrophobicity in Candida albicans serotype A and B strains. Infect Immun 2004; 72:6230-6. [PMID: 15501748 PMCID: PMC523023 DOI: 10.1128/iai.72.11.6230-6236.2004] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Cell surface hydrophobicity contributes to the pathogenesis of the opportunistic fungal pathogen Candida albicans. Previous work demonstrated a correlation between hydrophobicity status and changes in the acid-labile, phosphodiester-linked beta-1,2-oligomannoside components of the N-linked glycans of cell wall mannoprotein. Glycan composition also defines the two major serotypes, A and B, of C. albicans strains. Here, we show that the cell surface hydrophobicity of the two serotypes is qualitatively different, suggesting that the serotypes may differ in how they modulate cell surface hydrophobicity status. The cell wall mannoproteins from hydrophilic and hydrophobic cells of both serotypes were compared to determine whether the glycan differences due to serotype affect the glycan differences due to hydrophobicity status. Composition analysis showed that the protein, hexose, and phosphate contents of the mannoprotein fraction did not differ significantly among the strains tested. Electrophoretic profiles of the acid-labile mannan differed only with hydrophobicity status, not serotype, though some strain-specific differences were observed. Furthermore, a newly available beta-1,2-oligomannoside ladder allowed unambiguous identification of acid-labile mannan components. Finally, to assess whether the acid-stable mannan also affects cell surface hydrophobicity status, this fraction was fragmented into its component branches by acetolysis. The electrophoretic profiles of the acid-stable branches were very similar regardless of hydrophobicity status. However, differences were observed between serotypes. These results support and extend our current model that modification of the acid-labile beta-1,2-oligomannoside chain length but not modification of the acid-stable region is one common mechanism by which switching of cell surface hydrophobicity status of C. albicans strains occurs.
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Affiliation(s)
- James Masuoka
- Department of Pathology, University of Virginia Health System, Charlottesville 22908-0904, USA.
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Masuoka J. Surface glycans of Candida albicans and other pathogenic fungi: physiological roles, clinical uses, and experimental challenges. Clin Microbiol Rev 2004; 17:281-310. [PMID: 15084502 PMCID: PMC387410 DOI: 10.1128/cmr.17.2.281-310.2004] [Citation(s) in RCA: 122] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Although fungi have always been with us as commensals and pathogens, fungal infections have been increasing in frequency over the past few decades. There is a growing body of literature describing the involvement of carbohydrate groups in various aspects of fungal disease. Carbohydrates comprising the cell wall or capsule, or as a component of glycoproteins, are the fungal cell surface entities most likely to be exposed to the surrounding environment. Thus, the fungus-host interaction is likely to involve carbohydrates before DNA, RNA, or even protein. The interaction between fungal and host cells is also complex, and early studies using whole cells or crude cell fractions often produced seemingly conflicting results. What was needed, and what has been developing, is the ability to identify specific glycan structures and determine how they interact with immune system components. Carbohydrate analysis is complicated by the complexity of glycan structures and by the challenges of separating and detecting carbohydrates experimentally. Advances in carbohydrate chemistry have enabled us to move from the foundation of composition analysis to more rapid characterization of specific structures. This, in turn, will lead to a greater understanding of how fungi coexist with their hosts as commensals or exist in conflict as pathogens.
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Affiliation(s)
- James Masuoka
- Department of Pathology, University of Virginia, Charlottesville, Virginia 22908-0904, USA.
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Shibata N, Kobayashi H, Okawa Y, Suzuki S. Existence of novel beta-1,2 linkage-containing side chain in the mannan of Candida lusitaniae, antigenically related to Candida albicans serotype A. EUROPEAN JOURNAL OF BIOCHEMISTRY 2003; 270:2565-75. [PMID: 12787022 DOI: 10.1046/j.1432-1033.2003.03622.x] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
The antigenicity of Candida lusitaniae cells was found to be the same as that of Candida albicans serotype A cells, i.e. both cell wall mannans react with factors 1, 4, 5, and 6 sera of Candida Check. However, the structure of the mannan of C. lusitaniae was significantly different from that of C. albicans serotype A, and we found novel beta-1,2 linkages among the side-chain oligosaccharides, Manbeta1-->2Manbeta1--> 2Manalpha1-->2Manalpha1-->2Man (LM5), and Manbeta1-->2Man-beta1-->2Manbeta1-->2Manalpha1-->2Manalpha1-->2Man (LM6). The assignment of these oligosaccharides suggests that the mannoheptaose containing three beta-1,2 linkages obtained from the mannan of C. albicans in a preceding study consisted of isomers. The molar ratio of the side chains of C. lusitaniae mannan was determined from the complete assignment of its H-1 and H-2 signals and these signal dimensions. More than 80% of the oligomannosyl side chains contained beta-1,2-linked mannose units; no alpha-1,3 linkages or alpha-1,6-linked branching points were found in the side chains. An enzyme-linked immunosorbent inhibition assay using oligosaccharides indicated that LM5 behaves as factor 6, which is the serotype A-specific epitope of C. albicans. Unexpectedly, however, LM6 did not act as factor 6.
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Affiliation(s)
- Nobuyuki Shibata
- Second Department of Hygienic Chemistry, Tohoku Pharmaceutical University, Sendai, Miyagi, Japan
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Okawa Y, Monma K, Shibata N, Kobayashi H, Yamada Y. A new mannoheptaose containing alpha and beta-(1-->2) linkages isolated from the mannan of Torulaspora delbrueckii: ELISA inhibition studies. Carbohydr Res 2003; 338:1175-82. [PMID: 12747859 DOI: 10.1016/s0008-6215(03)00146-0] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Torulaspora delbrueckii starin IFO 0955 was examined with respect to its structural and serological properties of the cell wall mannan (Td-0955-M). Td-0955-M revealed significant reactivities with sera from a commercially available factor serum kit (Candida Check) in ELISA. Td-0955-M was investigated for its chemical structure by acetolysis under conventional and mild conditions. NMR and GC techniques were used as analytical techniques. The mannooligosaccharide fractions eluted from a Bio-Gel P-2 column were found to consist of Man(alpha1-2)Man, M2, Man(alpha1-2)Man(alpha1-2)Man and Man(beta1-2)Man(alpha1-2)Man, M3, Man(alpha1-2)Man(beta1-2)Man(beta1-2)Man(alpha1-2)Man, M5, and a new mannoheptaose, which possesses the structure, Man(alpha1-2)Man(beta1-2)Man(beta1-2)Man(beta1-2)Man(beta1-2)Man(alpha1-2)Man, M7. The results of the inhibition ELISA showed that the M7 oligosaccharide significantly inhibited the reactivities in the Td-0955-M-factor serum systems.
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Affiliation(s)
- Yoshio Okawa
- Second Department of Hygienic Chemistry, Tohoku Pharmaceutical University, 4-4-1 Komatsushima, Sendai Aoba-ku, 981-8558, Miyagi, Japan.
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Kruppa M, Goins T, Cutler JE, Lowman D, Williams D, Chauhan N, Menon V, Singh P, Li D, Calderone R. The role of the Candida albicans histidine kinase [CHK1) gene in the regulation of cell wall mannan and glucan biosynthesis. FEMS Yeast Res 2003; 3:289-99. [PMID: 12689636 DOI: 10.1111/j.1567-1364.2003.tb00170.x] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022] Open
Abstract
The human pathogen Candida albicans encodes at least three putative two-component histidine kinase signal transduction proteins, including Chk1p and a response regulator protein (Cssk1p). Strains deleted in CHK1 are avirulent in a murine model of hematogenously disseminated disease. The specific function of Chk1p has not been established, but hyphae of the chk1 mutant exhibit extensive flocculation while yeast forms are less adherent to reconstituted human esophageal tissue, indicating that this protein may regulate cell surface properties. Herein, we analyze glucan, mannan and chitin profiles in strains deleted in chk1 (CHK21) compared to a gene-reconstituted strain (CHK23) and a parental strain CAF2. Total alkali-soluble hexose from the cell wall of the chk1 mutant (strain CHK21) was significantly reduced. Western blots of cell wall extracts from CHK21, CHK23 and CAF2 reacted with a Mab to the acid-stable mannan fraction revealed extensive staining of lower molecular mass species in strain CHK21 only. FACE (fluorophore assisted carbohydrate electrophoresis) was used to characterize the oligosaccharide side chains of beta-eliminated (O-linked), acid-hydrolyzed (acid-labile phosphomannan) and acetolysis (acid-stable mannan) extracted fractions of total mannan. The profiles of O-linked as well as the acid-labile oligosaccharides were similar in both CAF2 and CHK21, but the acid-stable oligosaccharide side chains were significantly truncated. We also characterized the beta-glucan from each strain using NMR, and found that both the degree of polymerization and the ratio of (1-3)/(1-6) linkages was lower in CHK21 relative to wild-type cells. The sensitivity of CHK21 to antifungal drugs and inhibitors was unaffected. In summary, our data have identified a new function for a histidine kinase two-component signal protein in a human pathogenic fungus.
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Affiliation(s)
- Michael Kruppa
- Department of Microbiology and Immunology, Georgetown University Medical Center, Washington, DC 20007, USA
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Poulain D, Slomianny C, Jouault T, Gomez JM, Trinel PA. Contribution of phospholipomannan to the surface expression of beta-1,2-oligomannosides in Candida albicans and its presence in cell wall extracts. Infect Immun 2002; 70:4323-8. [PMID: 12117941 PMCID: PMC128193 DOI: 10.1128/iai.70.8.4323-4328.2002] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
beta-1,2-Oligomannosides (beta-1,2-Man) derived from Candida albicans mannan have been shown to act as adhesins and to induce protective antibodies. We used monoclonal antibodies specific for beta-1,2-Man in electron, confocal, and fluorescence microscopy to study the surface expression of beta-1,2-Man epitopes. These monoclonal antibodies were also used for Western blotting of cell surface extracts to study the nature of the molecules expressing the beta-Man epitopes. Evidence was obtained for the contribution of a glycolipid, phospholipomannan (PLM), to the complex expression of beta-1,2-Man epitopes at the cell wall surfaces of yeasts grown on solid media. PLM was present in intercellular matrixes of colonies grown on agar and was detected as a contaminant in mannan batches prepared by conventional methods.
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Affiliation(s)
- D Poulain
- Laboratoire de Mycologie Fondamentale et Appliquée, INSERM EPI 9915, Faculté de Médecine, Pôle Recherche, 59045 Lille Cedex, Italy.
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41
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Goins TL, Cutler JE. Relative abundance of oligosaccharides in Candida species as determined by fluorophore-assisted carbohydrate electrophoresis. J Clin Microbiol 2000; 38:2862-9. [PMID: 10921940 PMCID: PMC87130 DOI: 10.1128/jcm.38.8.2862-2869.2000] [Citation(s) in RCA: 45] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Fluorophore-assisted carbohydrate electrophoresis (FACE) is a straightforward, sensitive method for determining the presence and relative abundance of individual oligomannosyl residues in Candida mannoprotein, the major antigenic determinant located on the outer surface of the yeast cell wall. The single terminal aldehydes of oligomannosyl residues released by hydrolysis were tagged with the charged fluorophore 8-aminonaphthalene-1,3,6-trisulfonate (ANTS) and separated with high resolution on the basis of size by polyacrylamide gel electrophoresis. ANTS fluorescence labeling was not biased by oligomannoside length; therefore, band fluorescence intensity was directly related to the relative abundance of individual oligomannoside moieties in heterogeneous samples. FACE analysis revealed the major oligomannosides released by acid hydrolysis and beta-elimination of Fehling-precipitated mannan from Candida albicans, which were the same as those previously reported in studies based on mass and nuclear magnetic spectroscopic analysis. FACE was also amenable to the analysis of samples obtained by direct hydrolysis of whole yeast cells. Whole-cell acid hydrolysis and whole-cell beta-elimination of two isolates each of C. albicans, C. glabrata, C. krusei, C. lusitaniae, C. parapsilosis, C. rugosa, C. stellatoidea, and C. tropicalis resulted in oligomannoside gel banding patterns that were species and strain specific for the 16 isolates surveyed. Whereas some bands were specific for an individual isolate or species, other bands were shared by two or three species in various groupings. Differences in the mannoprotein composition of C. albicans A9 and four spontaneous cell surface mutants were also detected. Mannan "fingerprints," or banding pattern profiles, derived from the electrophoretic mobilities of individual bands relative to the migration of acid-hydrolyzed dextran (relative migration index) yielded profiles characteristic of individual isolates not revealed by standard assimilation and biochemical profiles. FACE represents an accessible, sensitive, and quantitative analytical tool enabling the characterization of yeast mannan complexity.
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Affiliation(s)
- T L Goins
- Department of Microbiology, Montana State University, Bozeman, Montana 59817, USA.
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Jacquinot PM, Plancke Y, Sendid B, Strecker G, Poulain D. Nature of Candida albicans-derived carbohydrate antigen recognized by a monoclonal antibody in patient sera and distribution over Candida species. FEMS Microbiol Lett 1998; 169:131-8. [PMID: 9851044 DOI: 10.1111/j.1574-6968.1998.tb13309.x] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022] Open
Abstract
The minimal epitope of an anti-Candida albicans mannan monoclonal antibody (MAb) EB-CA1, used to detect mannanemia in patient sera, was determined, MAb EB-CA1 exhibited reactivity with oligomannosides released from the mannan acid stable domain, converted into neoglycolipids (NGLs) and coated onto ELISA plates. Reactivity occurred with mannopentaose and higher oligomers, whereas mannotriose and mannotetraose were unreactive. MAb EB-CA1 binding to mannan acid stable mannopentaose NGL displayed a dose dependent and saturable specific reactivity curve whereas there was a complete absence of binding, even at high concentrations, with NGLs constructed from the beta-1,2-linked mannopentaose derived from the mannan acid labile fraction. MAb EB-CA1 binding to acid stable mannopentaose NGL was inhibited by the homologous oligomannoside but not by mannotriose and mannotetraose. NMR analysis showed that mannotriose and mannotetraose contained exclusively alpha-1,2-linked D-mannopyranose units and that mannopentaose was a mixture of a mannopentaose alpha-1,2-linked and an isomer in which the fifth mannose was alpha-1,6-linked to the reducing unit of manno-alpha-1,2 tetraose. Western blot analysis has shown that MAb EB-CA1 epitope was expressed on a wide range of C. albicans manno-glycoconjugate as well as on manno-glycoconjugates of other pathogenic species of the genus Candida, viz. C. tropicalis, C. glabrata, C. parapsilosis and C. krusei.
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Affiliation(s)
- P M Jacquinot
- Laboratoire de Mycologie Fondamentale et Appliquée, Centre Hospitalier Régional et Universitaire, Faculté de Médecine, Lille, France
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Zhang MX, Cutler JE, Han Y, Kozel TR. Contrasting roles of mannan-specific monoclonal immunoglobulin M antibodies in the activation of classical and alternative pathways by Candida albicans. Infect Immun 1998; 66:6027-9. [PMID: 9826391 PMCID: PMC108767 DOI: 10.1128/iai.66.12.6027-6029.1998] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Polyclonal antimannan immunoglobulin G (IgG) activates the classical complement pathway and accelerates initiation of the alternative pathway by Canidida albicans. This dual role was assessed for two antimannan IgM monoclonal antibodies (MAbs). MAb B6.1 is specific for an epitope on the acid-labile portion of C. albicans phosphomannan; MAb B6 is specific for an epitope on the acid-stable region. Both MAbs were potent activators of the classical pathway but poor facilitators of alternative pathway initiation.
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Affiliation(s)
- M X Zhang
- Department of Microbiology and the Cell and Molecular Biology Program, School of Medicine, University of Nevada, Reno, Nevada 89557, USA.
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HAIDO, SILVA, EJZEMBERG, LEITAO, HEARN, EVANS, BARRETO BERGTER. Analysis of peptidogalactomannans from the mycelial surface of Aspergillus fumigatus. Med Mycol 1998. [DOI: 10.1046/j.1365-280x.1998.00165.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
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45
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Zhang MX, Kozel TR. Mannan-specific immunoglobulin G antibodies in normal human serum accelerate binding of C3 to Candida albicans via the alternative complement pathway. Infect Immun 1998; 66:4845-50. [PMID: 9746588 PMCID: PMC108599 DOI: 10.1128/iai.66.10.4845-4850.1998] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Candida albicans activates the classical and alternative complement pathways, leading to deposition of opsonic complement fragments on the cell surface. Our previous studies found that antimannan immunoglobulin G (IgG) in normal human serum (NHS) allows C. albicans to initiate the classical pathway. The purpose of this study was to determine whether antimannan IgG also plays a role in initiation of the alternative pathway. Pooled NHS was rendered free of classical pathway activity by chelation of serum Ca2+ with EGTA alone or in combination with immunoaffinity removal of antimannan antibodies. Kinetic analysis revealed a 6-min lag in detection of C3 binding to C. albicans incubated in EGTA-chelated NHS, compared to a 12-min lag in NHS that was both EGTA chelated and mannan absorbed. The 12-min lag was shortened to 6 min by addition of affinity-purified antimannan IgG. The accelerating effect of antimannan IgG on alternative pathway initiation was dose dependent and was reproduced in a complement binding reaction consisting of six purified proteins of the alternative pathway. Both Fab and F(ab')2 fragments of antimannan IgG facilitated alternative pathway initiation in a manner similar to that observed with intact antibody. Immunofluorescence analysis showed that addition of antimannan IgG to EGTA-chelated and mannan-absorbed serum promoted an early deposition of C3 molecules on the yeast cells but had little or no effect on distribution of the cellular sites for C3 activation. Thus, antimannan IgG antibodies play an important regulatory role in interactions between the host complement system and C. albicans.
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Affiliation(s)
- M X Zhang
- Department of Microbiology and Cell and Molecular Biology Program, School of Medicine, University of Nevada, Reno, Nevada 89557, USA.
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46
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Chaffin WL, López-Ribot JL, Casanova M, Gozalbo D, Martínez JP. Cell wall and secreted proteins of Candida albicans: identification, function, and expression. Microbiol Mol Biol Rev 1998; 62:130-80. [PMID: 9529890 PMCID: PMC98909 DOI: 10.1128/mmbr.62.1.130-180.1998] [Citation(s) in RCA: 505] [Impact Index Per Article: 19.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
The cell wall is essential to nearly every aspect of the biology and pathogenicity of Candida albicans. Although it was initially considered an almost inert cellular structure that protected the protoplast against osmotic offense, more recent studies have demonstrated that it is a dynamic organelle. The major components of the cell wall are glucan and chitin, which are associated with structural rigidity, and mannoproteins. The protein component, including both mannoprotein and nonmannoproteins, comprises some 40 or more moieties. Wall proteins may differ in their expression, secretion, or topological location within the wall structure. Proteins may be modified by glycosylation (primarily addition of mannose residues), phosphorylation, and ubiquitination. Among the secreted enzymes are those that are postulated to have substrates within the cell wall and those that find substrates in the extracellular environment. Cell wall proteins have been implicated in adhesion to host tissues and ligands. Fibrinogen, complement fragments, and several extracellular matrix components are among the host proteins bound by cell wall proteins. Proteins related to the hsp70 and hsp90 families of conserved stress proteins and some glycolytic enzyme proteins are also found in the cell wall, apparently as bona fide components. In addition, the expression of some proteins is associated with the morphological growth form of the fungus and may play a role in morphogenesis. Finally, surface mannoproteins are strong immunogens that trigger and modulate the host immune response during candidiasis.
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Affiliation(s)
- W L Chaffin
- Department of Microbiology and Immunology, Texas Tech University Health Sciences Center, Lubbock 79430, USA.
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47
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Jungmann J, Munro S. Multi-protein complexes in the cis Golgi of Saccharomyces cerevisiae with alpha-1,6-mannosyltransferase activity. EMBO J 1998; 17:423-34. [PMID: 9430634 PMCID: PMC1170393 DOI: 10.1093/emboj/17.2.423] [Citation(s) in RCA: 181] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
Anp1p, Van1p and Mnn9p constitute a family of membrane proteins required for proper Golgi function in Saccharomyces cerevisiae. We demonstrate that these proteins colocalize within the cis Golgi, and that they are physically associated in two distinct complexes, both of which contain Mnn9p. Furthermore, we identify two new proteins in the Anp1p-Mnn9p-containing complex which have homology to known glycosyltransferases. Both protein complexes have alpha-1, 6-mannosyltransferase activity, forming a series of poly-mannose structures. These reaction products also contain some alpha-1, 2-linked mannose residues. Our data suggest that these two multi-protein complexes are responsible for the synthesis and initial branching of the long alpha-1,6-linked backbone of the hypermannose structure attached to many yeast glycoproteins.
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Affiliation(s)
- J Jungmann
- MRC Laboratory of Molecular Biology, Cambridge, UK
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48
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Martínez JP, Gil ML, López-Ribot JL, Chaffin WL. Serologic response to cell wall mannoproteins and proteins of Candida albicans. Clin Microbiol Rev 1998; 11:121-41. [PMID: 9457431 PMCID: PMC121378 DOI: 10.1128/cmr.11.1.121] [Citation(s) in RCA: 121] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
The cell wall of Candida albicans not only is the structure in which many biological functions essential for the fungal cells reside but also is a significant source of candidal antigens. The major cell wall components that elicit a response from the host immune system are proteins and glycoproteins, the latter being predominantly mannoproteins. Both the carbohydrate and protein moieties are able to trigger immune responses. Although cell-mediated immunity is often considered to be the most important line of defense against candidiasis, cell wall protein and glycoprotein components also elicit a potent humoral response from the host that may include some protective antibodies. Proteins and glycoproteins exposed at the most external layers of the wall structure are involved in several types of interactions of fungal cells with the exocellular environment. Thus, coating of fungal cells with host antibodies has the potential to influence profoundly the host-parasite interaction by affecting antibody-mediated functions such as opsonin-enhanced phagocytosis and blocking the binding activity of fungal adhesins for host ligands. In this review, the various members of the protein and glycoprotein fraction of the C. albicans cell wall that elicit an antibody response in vivo are examined. Although a number of proteins have been shown to stimulate an antibody response, for some of these species the response is not universal. On the other hand, some of the studies demonstrate that certain cell wall antigens and anti-cell wall antibodies may be the basis for developing specific and sensitive serologic tests for the diagnosis of candidasis, particularly the disseminated form. In addition, recent studies have focused on the potential for antibodies to cell wall protein determinants to protect the host against infection. Hence, a better understanding of the humoral response to cell wall antigens of C. albicans may provide the basis for the development of (i) effective procedures for the serodiagnosis of disseminated candidiasis and (ii) novel prophylactic (vaccination) and therapeutic strategies for the management of this type of infection.
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Affiliation(s)
- J P Martínez
- Departamento de Microbiología y Ecología, Facultad de Farmacia, Universitat de València, Spain.
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49
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Haido R, Silva M, Ejzemberg R, Leitão E, Hearn V, Evans E, Bergter EB. Analysis of peptidogalactomannans from the mycelial surface ofAspergillus fumigatus. Med Mycol 1998. [DOI: 10.1080/02681219880000491] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022] Open
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50
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Zhang MX, Lupan DM, Kozel TR. Mannan-specific immunoglobulin G antibodies in normal human serum mediate classical pathway initiation of C3 binding to Candida albicans. Infect Immun 1997; 65:3822-7. [PMID: 9284158 PMCID: PMC175545 DOI: 10.1128/iai.65.9.3822-3827.1997] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
Candida albicans activates both the classical and alternative complement pathways. Previous studies found that immunoglobulin G (IgG) in normal human serum (NHS) mediates classical pathway initiation. The goal of this study was to determine the role of candidal mannan-specific human IgG antibodies in complement activation. Mannan was purified from the yeast cells, and naturally occurring antimannan IgG was isolated from pooled NHS or plasma samples by immunoaffinity chromatography. Early activation and binding of C3, characteristics of classical pathway activity, were abolished in yeast- or mannan-absorbed serum but could be restored to absorbed serum with added purified antimannan IgG in a dose-dependent manner. Microscopically, the immunofluorescence pattern of initial C3 binding was diffuse over the entire cell surface for yeast cells incubated in NHS or in mannan-absorbed NHS supplemented with antimannan IgG but was asynchronous and focal for yeast cells incubated in EGTA-treated or mannan-absorbed NHS. The antimannan IgG level in serum samples from 21 donors varied from 17 to 570 microg/ml of serum compared to 220 microg in pooled NHS samples. The rate of initial C3 binding to yeast cells correlated with the level of antimannan IgG in sera from different individuals (r2 = 0.94) and could be accelerated in sera containing lower amounts of antimannan IgG with exogenous antimannan IgG. These observations identify antimannan IgG as the initiator of classical pathway C3 deposition on C. albicans. Given the variability in the levels of antimannan antibodies in sera from different individuals, the presence or absence of these antibodies may be an important determinant of host resistance to disseminated candidiasis.
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Affiliation(s)
- M X Zhang
- Department of Microbiology and Cell and Molecular Biology Program, School of Medicine, University of Nevada, Reno 89557, USA.
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