Alarmin(g) the innate immune system to invasive fungal infections

β-(1,3)-Glucan Unmasking in Some Candida albicans Mutants Correlates with Increases in Cell Wall Surface Roughness and Decreases in Cell Wall Elasticity

Infection and Immunity ◽

10.1128/iai.00601-16 ◽

2016 ◽

Vol 85 (1) ◽

Cited By ~ 18

Author(s):

Sahar Hasim ◽

David P. Allison ◽

Scott T. Retterer ◽

Alex Hopke ◽

Robert T. Wheeler ◽

...

Keyword(s):

Cell Wall ◽

Candida Albicans ◽

Immune System ◽

Innate Immune System ◽

Fungal Infections ◽

Innate Immune ◽

Surface Topology ◽

Wild Type ◽

Content Type ◽

Cell Wall Elasticity

ABSTRACT Candida albicans is among the most common human fungal pathogens, causing a broad range of infections, including life-threatening systemic infections. The cell wall of C. albicans is the interface between the fungus and the innate immune system. The cell wall is composed of an outer layer enriched in mannosylated glycoproteins (mannan) and an inner layer enriched in β-(1,3)-glucan and chitin. Detection of C. albicans by Dectin-1, a C-type signaling lectin specific for β-(1,3)-glucan, is important for the innate immune system to recognize systemic fungal infections. Increased exposure of β-(1,3)-glucan to the immune system occurs when the mannan layer is altered or removed in a process called unmasking. Nanoscale changes to the cell wall during unmasking were explored in live cells with atomic force microscopy (AFM). Two mutants, the cho1Δ/Δ and kre5Δ/Δ mutants, were selected as representatives that exhibit modest and strong unmasking, respectively. Comparisons of the cho1Δ/Δ and kre5Δ/Δ mutants to the wild type reveal morphological changes in their cell walls that correlate with decreases in cell wall elasticity. In addition, AFM tips functionalized with Dectin-1 revealed that the forces of binding of Dectin-1 to all of the strains were similar, but the frequency of binding was highest for the kre5Δ/Δ mutant, decreased for the cho1Δ/Δ mutant, and rare for the wild type. These data show that nanoscale changes in surface topology are correlated with increased Dectin-1 adhesion and decreased cell wall elasticity. AFM, using tips functionalized with immunologically relevant molecules, can map epitopes of the cell wall and increase our understanding of pathogen recognition by the immune system.

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Eosinophils and Neutrophils—Molecular Differences Revealed by Spontaneous Raman, CARS and Fluorescence Microscopy

Cells ◽

10.3390/cells9092041 ◽

2020 ◽

Vol 9 (9) ◽

pp. 2041

Author(s):

Aleksandra Dorosz ◽

Marek Grosicki ◽

Jakub Dybas ◽

Ewelina Matuszyk ◽

Marko Rodewald ◽

...

Keyword(s):

Immune System ◽

Immune Responses ◽

Innate Immune System ◽

Fungal Infections ◽

Innate Immune ◽

Lipid Bodies ◽

Blood Samples ◽

Cars Microscopy ◽

Specific Granules ◽

Anti Stokes

Leukocytes are a part of the immune system that plays an important role in the host’s defense against viral, bacterial, and fungal infections. Among the human leukocytes, two granulocytes, neutrophils (Ne) and eosinophils (EOS) play an important role in the innate immune system. For that purpose, eosinophils and neutrophils contain specific granules containing protoporphyrin-type proteins such as eosinophil peroxidase (EPO) and myeloperoxidase (MPO), respectively, which contribute directly to their anti-infection activity. Since both proteins are structurally and functionally different, they could potentially be a marker of both cells’ types. To prove this hypothesis, UV−Vis absorption spectroscopy and Raman imaging were applied to analyze EPO and MPO and their content in leukocytes isolated from the whole blood. Moreover, leukocytes can contain lipidic structures, called lipid bodies (LBs), which are linked to the regulation of immune responses and are considered to be a marker of cell inflammation. In this work, we showed how to determine the number of LBs in two types of granulocytes, EOS and Ne, using fluorescence and coherent anti-Stokes Raman scattering (CARS) microscopy. Spectroscopic differences of EPO and MPO can be used to identify these cells in blood samples, while the detection of LBs can indicate the cell inflammation process.

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Investigation of Anti-Infection Mechanism of Lactoferricin and Splunc-1

Evidence-based Complementary and Alternative Medicine ◽

10.1155/2014/907028 ◽

2014 ◽

Vol 2014 ◽

pp. 1-10 ◽

Cited By ~ 3

Author(s):

Yung An Tsou ◽

Hung-Jin Huang ◽

Wesley Wen Yang Lin ◽

Calvin Yu-Chian Chen

Keyword(s):

Immune System ◽

Innate Immune System ◽

Fungal Infections ◽

The Body ◽

Innate Immune ◽

Epithelial Tissue ◽

Defense System ◽

First Line ◽

Gram Negative ◽

Infection Source

The innate immune system is the first line in the defense system and prevents the body from further bacteria, virus, or fungal infections. Most of the innate immune system is relevant to mucosa immunity. Lactotransferrin is secreted from the human mammal breast duct epithelial tissue and strengthens infant immunity to defense with regard to outward pathogens. Splunc-1 is also an innate material secreted from the soft palate, lung, nasal cavity epithelium, and mucosa. It helps with mucosa defense against bacterial, virus, and even fungus. LPS is the main etiology of Gram-negative bacilla infection source. And studies of lactoferricin and slpunc-1 both can combine with LPS and subsequently cause insults to the mucosa. Although, we know that both of them partake in an important role in innate immunity, we do not know the effects when they work together. In this study, we just overview silicon stimulation to examine the combination of Lactoferricin and Splunc-1 and the effect with regard to LPS.

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