Rapid determination of binding parameters of chitin binding domains using chitin-coated quartz crystal microbalance sensor chips

Abstract Leukocyte reduced NADP (NADPH) oxidase plays a key role in host defense and immune regulation. Genetic defects in NADPH oxidase result in chronic granulomatous disease (CGD), characterized by recurrent bacterial and fungal infections and aberrant inflammation. Key drivers of hyperinflammation induced by fungal cell walls in CGD are still incompletely defined. In this study, we found that CGD (CYBB−) neutrophils produced higher amounts of leukotriene B4 (LTB4) in vitro after activation with zymosan or immune complexes, compared with wild-type (WT) neutrophils. This finding correlated with increased calcium influx in CGD neutrophils, which was restrained in WT neutrophils by the electrogenic activity of NADPH oxidase. Increased LTB4 generation by CGD neutrophils was also augmented by paracrine cross talk with the LTB4 receptor BLT1. CGD neutrophils formed more numerous and larger clusters in the presence of zymosan in vitro compared with WT cells, and the effect was also LTB4- and BLT1-dependent. In zymosan-induced lung inflammation, focal neutrophil infiltrates were increased in CGD compared with WT mice and associated with higher LTB4 levels. Inhibiting LTB4 synthesis or antagonizing the BLT1 receptor after zymosan challenge reduced lung neutrophil recruitment in CGD to WT levels. Thus, LTB4 was the major driver of excessive neutrophilic lung inflammation in CGD mice in the early response to fungal cell walls, likely by a dysregulated feed-forward loop involving amplified neutrophil production of LTB4. This study identifies neutrophil LTB4 generation as a target of NADPH oxidase regulation, which could potentially be exploited therapeutically to reduce excessive inflammation in CGD.

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Determination of Glucosamine andN-Acetyl Glucosamine in Fungal Cell Walls

Journal of Agricultural and Food Chemistry ◽

10.1021/jf801478j ◽

2008 ◽

Vol 56 (18) ◽

pp. 8314-8318 ◽

Cited By ~ 54

Author(s):

Akram Zamani ◽

Azam Jeihanipour ◽

Lars Edebo ◽

Claes Niklasson ◽

Mohammad J. Taherzadeh

Keyword(s):

Cell Walls ◽

Fungal Cell ◽

Fungal Cell Walls

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Structure and Synthesis of Fungal Cell Walls

10.1017/9781108776387.007 ◽

2020 ◽

pp. 171-191

Keyword(s):

Cell Walls ◽

Fungal Cell ◽

Fungal Cell Walls

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Screening and Antifungal Activity of a β-Carboline Derivative against Cryptococcus neoformans and C. gattii

International Journal of Microbiology ◽

10.1155/2019/7157845 ◽

2019 ◽

Vol 2019 ◽

pp. 1-8 ◽

Cited By ~ 1

Author(s):

Kátia Santana Cruz ◽

Emerson Silva Lima ◽

Marcia de Jesus Amazonas da Silva ◽

Erica Simplício de Souza ◽

Andreia Montoia ◽

...

Keyword(s):

Cell Wall ◽

Candida Albicans ◽

Antifungal Activity ◽

Cryptococcus Neoformans ◽

Active Compound ◽

Cell Walls ◽

Human Fibroblasts ◽

Lead Compound ◽

Fungal Cell ◽

Fungal Cell Walls

Background. Cryptococcosis is a fungal disease of bad prognosis due to its pathogenicity and the toxicity of the drugs used for its treatment. The aim of this study was to investigate the medicinal potential of carbazole and β-carboline alkaloids and derivatives against Cryptococcus neoformans and C. gattii. Methods. MICs were established in accordance with the recommendations of the Clinical and Laboratory Standards Institute for alkaloids and derivatives against C. neoformans and C. gattii genotypes VNI and VGI, respectively. A single active compound was further evaluated against C. neoformans genotypes VNII, VNIII, and VNIV, C. gattii genotypes VGI, VGIII, and VGIV, Candida albicans ATCC 36232, for cytotoxicity against the MRC-5 lineage of human fibroblasts and for effects on fungal cells (cell wall, ergosterol, and leakage of nucleic acids). Results. Screening of 11 compounds revealed 8-nitroharmane as a significant inhibitor (MIC 40 μg/mL) of several C. neoformans and C. gattii genotypes. It was not toxic to fibroblasts (IC50 > 50 µg/mL) nor did it alter fungal cell walls or the concentration of ergosterol in C. albicans or C. neoformans. It increased leakage of substances that absorb at 260 nm. Conclusions. The synthetic β-carboline 8-nitroharmane significantly inhibits pathogenic Cryptococcus species and is interesting as a lead compound towards new therapy for Cryptococcus infections.

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