scholarly journals In vitro and in vivo reactivity to fungal cell wall agents in sarcoidosis

2011 ◽  
Vol 166 (1) ◽  
pp. 87-93 ◽  
Author(s):  
M. Terčelj ◽  
S. Stopinšek ◽  
A. Ihan ◽  
B. Salobir ◽  
S. Simčič ◽  
...  
Keyword(s):  
Cell Wall ◽  
Fungal Cell Wall ◽  
Fungal Cell

scholarly journals Monoclonal Immunoglobulin G1 Directed against Aspergillus fumigatus Cell Wall Glycoprotein Protects against Experimental Murine Aspergillosis

2005 ◽  
Vol 12 (9) ◽  
pp. 1063-1068 ◽  
Author(s):  
Ashok K. Chaturvedi ◽  
A. Kavishwar ◽  
G. B. Shiva Keshava ◽  
P. K. Shukla
Keyword(s):  
Cell Wall ◽  
Aspergillus Fumigatus ◽  
Protective Efficacy ◽  
Wide Spectrum ◽  
Kidney Tissue ◽  
Survival Times ◽  
Fungal Cell ◽  
New Strategy

ABSTRACT Most of the biological functions related to pathogenicity and virulence reside in the fungal cell wall, which, being the outermost part of the cell, mediates the host-fungus interplay. For these reasons much effort has focused on the discovery of useful inhibitors of cell wall glucan, chitin, and mannoprotein biosynthesis. In the absence of a wide-spectrum, safe, and potent antifungal agent, a new strategy for antifungal therapy is directed towards the development of monoclonal antibodies (MAbs). In the present study the MAb A9 (immunoglobulin G1 [IgG1]) was identified from hybridomas raised in BALB/c mice immunized with cell wall antigen of Aspergillus fumigatus. The immunoreactive epitopes for this IgG1 MAb appeared to be associated with a peptide moiety, and indirect immunofluorescence microscopy revealed its binding to the cell wall surface of hyphae as well as with swollen conidia. MAb A9 inhibited hyphal development as observed by MTT [3-(4,5-dimethythiazol-2-yl)-2,5-diphenyltetrazolium bromide] assay (25.76%), reduced the duration of spore germination, and exerted an in vitro cidal effect against Aspergillus fumigatus. The in vivo protective efficacy of MAb A9 was also evaluated in a murine model of invasive aspergillosis, where a reduction in CFU (>4 log10 units) was observed in kidney tissue of BALB/c mice challenged with A. fumigatus (2 × 105 CFU/ml) and where enhanced mean survival times (19.5 days) compared to the control (7.1 days) and an irrelevant MAb (6.1 days) were also observed.

scholarly journals The Glycosylphosphatidylinositol-Anchored DFG Family Is Essential for the Insertion of Galactomannan into the β-(1,3)-Glucan–Chitin Core of the Cell Wall of Aspergillus fumigatus

mSphere ◽  
2019 ◽  
Vol 4 (4) ◽  
Author(s):  
Laetitia Muszkieta ◽  
Thierry Fontaine ◽  
Rémi Beau ◽  
Isabelle Mouyna ◽  
Marian Samuel Vogt ◽  
...  
Keyword(s):  
Cell Wall ◽  
Aspergillus Fumigatus ◽  
Gene Family ◽  
Protein Complexes ◽  
Growth Conditions ◽  
Fungal Cell Wall ◽  
Cross Linking ◽  
Fungal Cell ◽  
Content Type

ABSTRACT The fungal cell wall is a complex and dynamic entity essential for the development of fungi. It is composed mainly of polysaccharides that are synthetized by protein complexes. At the cell wall level, enzyme activities are involved in postsynthesis polysaccharide modifications such as cleavage, elongation, branching, and cross-linking. Glycosylphosphatidylinositol (GPI)-anchored proteins have been shown to participate in cell wall biosynthesis and specifically in polysaccharide remodeling. Among these proteins, the DFG family plays an essential role in controlling polar growth in yeast. In the filamentous fungus and opportunistic human pathogen Aspergillus fumigatus, the DFG gene family contains seven orthologous DFG genes among which only six are expressed under in vitro growth conditions. Deletions of single DFG genes revealed that DFG3 plays the most important morphogenetic role in this gene family. A sextuple-deletion mutant resulting from the deletion of all in vitro expressed DFG genes did not contain galactomannan in the cell wall and has severe growth defects. This study has shown that DFG members are absolutely necessary for the insertion of galactomannan into the cell wall of A. fumigatus and that the proper cell wall localization of the galactomannan is essential for correct fungal morphogenesis in A. fumigatus. IMPORTANCE The fungal cell wall is a complex and dynamic entity essential for the development of fungi. It is composed mainly of polysaccharides that are synthetized by protein complexes. Enzymes involved in postsynthesis polysaccharide modifications, such as cleavage, elongation, branching, and cross-linking, are essential for fungal life. Here, we investigated in Aspergillus fumigatus the role of the members of the Dfg family, one of the 4 GPI-anchored protein families common to yeast and molds involved in cell wall remodeling. Molecular and biochemical approaches showed that DFG members are required for filamentous growth, conidiation, and cell wall organization and are essential for the life of this fungal pathogen.

Localization of fungal fimbriae by immunocytochemistry in pathogenic and nonpathogenic isolates of Venturia inaequalis

2000 ◽  
Vol 46 (9) ◽  
pp. 800-808 ◽  
Author(s):  
Antonet M Svircev ◽  
Ronald J Smith ◽  
Ting Zhou ◽  
Alan W Day
Keyword(s):  
Cell Wall ◽  
Venturia Inaequalis ◽  
Fungal Cell Wall ◽  
Fungal Mycelium ◽  
Fungal Cell ◽  
Transmission Electron ◽  
Developmental Growth ◽  
Large Central Vacuole ◽  
Cellular Organelles

Pathogenic and nonpathogenic isolates of Venturia inaequalis were grown in liquid culture. Hyphae were treated with two types of fimbrial antiserum (AU- and AV-1) and examined by immunofluorescent microscopy, in order to establish the distribution of fimbrial epitopes in whole cell mounts. The AV-1 antiserum was specific for the glycoprotein subunits while the AU- antiserum was specific for the protein moieties present on the fimbriae of Mycobotryum violaceum. The use of fimbrial antiserum with immunocytochemistry and transmission electron microscopy demonstrated a clear distinction between pathogenic and nonpathogenic isolates of V. inaequalis, based on the appearance of the fungal cell wall and the distribution of fimbrial epitopes labeled with AV-1 antiserum and immunogold complex. In actively growing hyphae of the pathogenic isolate, characterized by distinct cellular organelles, small vacuoles, and lipid bodies, fimbrial epitopes were concentrated in the fungal cell wall and were present minimally on the outer surface. In contrast, actively growing hyphae of the nonpathogenic isolate of V. inaequalis had extensive fine hair-like protrusions in the fungal cell wall which labeled with the AV-1 antiserum and immunogold. The distribution of fimbrial epitopes in V. inaequalis was highly dependent on the developmental growth stage of the fungal mycelium. Aging mycelia in both the pathogenic and nonpathogenic isolates of V. inaequalis were characterized by a large central vacuole and no label. In the pathogenic and nonpathogenic isolates of V. inaequalis grown in vitro, the distribution of fimbrial glycoprotein epitopes provided a more complex profile than that seen in M. violaceum.Key words: fimbriae, immunocytochemistry, Venturia inaequalis, Mycobotryum violaceum.

In vitro antifungal activity of new series of homoallylamines and related compounds with inhibitory properties of the synthesis of fungal cell wall polymers

2003 ◽  
Vol 11 (7) ◽  
pp. 1531-1550 ◽  
Author(s):  
Leonor Y Vargas M ◽  
Marı́a V Castelli ◽  
Vladimir V Kouznetsov ◽  
Juan M Urbina G ◽  
Silvia N López ◽  
...  
Keyword(s):  
Cell Wall ◽  
Antifungal Activity ◽  
Fungal Cell Wall ◽  
Fungal Cell ◽  
Cell Wall Polymers ◽  
Related Compounds ◽  
In Vitro Antifungal Activity

scholarly journals In-vitro Detection of Phytopathogenic Fungal Cell Wall by Polyclonal Sera Raised Against Trimethyl Chitosan Nanoparticles

2019 ◽  
Vol Volume 14 ◽  
pp. 10023-10033
Author(s):  
Hemant Joshi ◽  
Anshu Malik ◽  
Soumya Aggarwal ◽  
Manoj Munde ◽  
Subhrangsu Sundar Maitra ◽  
...  
Keyword(s):  
Cell Wall ◽  
Chitosan Nanoparticles ◽  
Fungal Cell Wall ◽  
Fungal Cell ◽  
Trimethyl Chitosan

scholarly journals Critical Assessment of Cell Wall Integrity Factors Contributing to in vivo Echinocandin Tolerance and Resistance in Candida glabrata

2021 ◽  
Vol 12 ◽  
Author(s):  
Rocio Garcia-Rubio ◽  
Rosa Y. Hernandez ◽  
Alissa Clear ◽  
Kelley R. Healey ◽  
Erika Shor ◽  
...  
Keyword(s):  
Cell Wall ◽  
Candida Glabrata ◽  
Fungal Infections ◽  
Critical Role ◽  
Cell Wall Integrity ◽  
Fungal Cell ◽  
Fungal Host

Fungal infections are on the rise, and emergence of drug-resistant Candida strains refractory to treatment is particularly alarming. Resistance to azole class antifungals, which have been extensively used worldwide for several decades, is so high in several prevalent fungal pathogens, that another drug class, the echinocandins, is now recommended as a first line antifungal treatment. However, resistance to echinocandins is also prominent, particularly in certain species, such as Candida glabrata. The echinocandins target 1,3-β-glucan synthase (GS), the enzyme responsible for producing 1,3-β-glucans, a major component of the fungal cell wall. Although echinocandins are considered fungicidal, C. glabrata exhibits echinocandin tolerance both in vitro and in vivo, where a subset of the cells survives and facilitates the emergence of echinocandin-resistant mutants, which are responsible for clinical failure. Despite this critical role of echinocandin tolerance, its mechanisms are still not well understood. Additionally, most studies of tolerance are conducted in vitro and are thus not able to recapitulate the fungal-host interaction. In this study, we focused on the role of cell wall integrity factors in echinocandin tolerance in C. glabrata. We identified three genes involved in the maintenance of cell wall integrity – YPS1, YPK2, and SLT2 – that promote echinocandin tolerance both in vitro and in a mouse model of gastrointestinal (GI) colonization. In particular, we show that mice colonized with strains carrying deletions of these genes were more effectively sterilized by daily caspofungin treatment relative to mice colonized with the wild-type parental strain. Furthermore, consistent with a role of tolerant cells serving as a reservoir for generating resistant mutations, a reduction in tolerance was associated with a reduction in the emergence of resistant strains. Finally, reduced susceptibility in these strains was due both to the well described FKS-dependent mechanisms and as yet unknown, FKS-independent mechanisms. Together, these results shed light on the importance of cell wall integrity maintenance in echinocandin tolerance and emergence of resistance and lay the foundation for future studies of the factors described herein.

In vitro and in vivo polysaccharides assembly: ultrastructural and cytochemical study of growing plant cell wall components.

1978 ◽  
Vol 36 (2) ◽  
pp. 434-435
Author(s):  
D. Reis ◽  
B. Vian ◽  
J. C. Roland
Keyword(s):  
Cell Wall ◽  
Self Assembly ◽  
Plant Cell Wall ◽  
Higher Plants ◽  
Three Dimensional ◽  
Cytochemical Study ◽  
Wall Components

Wall morphogenesis in higher plants is a problem still open to controversy. Until now the possibility of a transmembrane control and the involvement of microtubules were mostly envisaged. Self-assembly processes have been observed in the case of walls of Chlamydomonas and bacteria. Spontaneous gelling interactions between xanthan and galactomannan from Ceratonia have been analyzed very recently. The present work provides indications that some processes of spontaneous aggregation could occur in higher plants during the formation and expansion of cell wall.Observations were performed on hypocotyl of mung bean (Phaseolus aureus) for which growth characteristics and wall composition have been previously defined.In situ, the walls of actively growing cells (primary walls) show an ordered three-dimensional organization (fig. 1). The wall is typically polylamellate with multifibrillar layers alternately transverse and longitudinal. Between these layers intermediate strata exist in which the orientation of microfibrils progressively rotates. Thus a progressive change in the morphogenetic activity occurs.

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