Chitin and chitinases in allergic reactions

Chitin - the structural component of fungal cell wall, arthropodal exoskeleton, microfilarial sheat and egg of helminths. Allergens of this organisms cause allergic diseases. The potential role of chitin in allergic reactions has been discussed. Other studies have suggested that chitin preparations may skew immunity away from T-helper-2-mediated allergic responses. Chitinases, enzymes that can degrade chitin polymer, and chitinase-like proteins might also play an important role in allergic disease pathogenesis.

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Development of chronic allergic responses by dampening Bcl6-mediated suppressor activity in memory T helper 2 cells

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.1613528114 ◽

2017 ◽

Vol 114 (5) ◽

pp. E741-E750 ◽

Cited By ~ 6

Author(s):

Takashi Ogasawara ◽

Masahiko Hatano ◽

Hisae Satake ◽

Jun Ikari ◽

Toshibumi Taniguchi ◽

...

Keyword(s):

Molecular Mechanisms ◽

Cytokine Production ◽

Allergic Diseases ◽

Cytokine Gene ◽

T Helper ◽

Suppressor Activity ◽

T Helper 2 ◽

Asthma Model ◽

Murine Asthma Model

Mice deficient in the transcriptional repressor B-cell CLL/lymphoma 6 (Bcl6) exhibit similar T helper 2 (TH2) immune responses as patients with allergic diseases. However, the molecular mechanisms underlying Bcl6-directed regulation of TH2 cytokine genes remain unclear. We identified multiple Bcl6/STAT binding sites (BSs) in TH2 cytokine gene loci. We found that Bcl6 is modestly associated with the BSs, and it had no significant effect on cytokine production in newly differentiated TH2 cells. Contrarily, in memory TH2 (mTH2) cells derived from adaptively transferred TH2 effectors, Bcl6 outcompeted STAT5 for binding to TH2 cytokine gene loci, particularlyInterleukin4(Il4) loci, and attenuated GATA binding protein 3 (GATA3) binding to highly conserved intron enhancer regions in mTH2 cells. Bcl6 suppressed cytokine production epigenetically in mTH2 cells to negatively tune histone acetylation at TH2 cytokine gene loci, includingIl4loci. In addition, IL-33, a pro-TH2 cytokine, diminished Bcl6’s association with loci to which GATA3 recruitment was inversely augmented, resulting in altered IL-4, but not IL-5 and IL-13, production in mTH2 cells but no altered production in newly differentiated TH2 cells. Use of a murine asthma model that generates high levels of pro-TH2 cytokines, such as IL-33, suggested that the suppressive function of Bcl6 in mTH2 cells is abolished in severe asthma. These findings indicate a role of the interaction between TH2-promoting factors and Bcl6 in promoting appropriate IL-4 production in mTH2 cells and suggest that chronic allergic diseases involve the TH2-promoting factor-mediated functional breakdown of Bcl6, resulting in allergy exacerbation.

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New view on alcoholic liver disease - potential role of PD1/PDL-1 pathway in the disease pathogenesis

Journal of Education, Health and Sport ◽

10.12775/jehs.2019.09.11.009 ◽

2019 ◽

Vol 9 (11) ◽

pp. 121

Author(s):

Katarzyna Adamczyk ◽

Beata Kasztelan-Szczerbińska ◽

Anna Rycyk ◽

Halina Cichoż-Lach

Keyword(s):

Liver Disease ◽

Alcoholic Liver Disease ◽

Potential Role ◽

Disease Pathogenesis ◽

New View

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Protein Glycosylation inAspergillus fumigatusIs Essential for Cell Wall Synthesis and Serves as a Promising Model of Multicellular Eukaryotic Development

International Journal of Microbiology ◽

10.1155/2012/654251 ◽

2012 ◽

Vol 2012 ◽

pp. 1-21 ◽

Cited By ~ 14

Author(s):

Cheng Jin

Keyword(s):

Saccharomyces Cerevisiae ◽

Cell Wall ◽

Posttranslational Modification ◽

Mammalian Cells ◽

Protein Glycosylation ◽

Cell Wall Synthesis ◽

Fungal Cell ◽

Multiple Functions ◽

Significant Attention

Glycosylation is a conserved posttranslational modification that is found in all eukaryotes, which helps generate proteins with multiple functions. Our knowledge of glycosylation mainly comes from the investigation of the yeastSaccharomyces cerevisiaeand mammalian cells. However, during the last decade, glycosylation in the human pathogenic moldAspergillus fumigatushas drawn significant attention. It has been revealed that glycosylation inA. fumigatusis crucial for its growth, cell wall synthesis, and development and that the process is more complicated than that found in the budding yeastS. cerevisiae. The present paper implies that the investigation of glycosylation inA. fumigatusis not only vital for elucidating the mechanism of fungal cell wall synthesis, which will benefit the design of new antifungal therapies, but also helps to understand the role of protein glycosylation in the development of multicellular eukaryotes. This paper describes the advances in functional analysis of protein glycosylation inA. fumigatus.

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Allergic reactions to the first COVID‐19 vaccine: a potential role of Polyethylene glycol?

Allergy ◽

10.1111/all.14711 ◽

2020 ◽

Author(s):

Beatriz Cabanillas ◽

Cezmi Akdis ◽

Natalija Novak

Keyword(s):

Polyethylene Glycol ◽

Potential Role ◽

Allergic Reactions

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Editorial: The Role of the Fungal Cell Wall in Host-Fungal Interactions

Frontiers in Cellular and Infection Microbiology ◽

10.3389/fcimb.2020.00392 ◽

2020 ◽

Vol 10 ◽

Author(s):

Laura Alcazar-Fuoli ◽

Jagadeesh Bayry ◽

Vishukumar Aimanianda

Keyword(s):

Cell Wall ◽

Fungal Cell Wall ◽

Fungal Cell ◽

Fungal Interactions

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Role of beta1 and beta2 subunits of the interleukin-12 receptor in determining T helper 1/T helper 2 responses in vivo in the rat

Immunology ◽

10.1046/j.1365-2567.2000.00927.x ◽

2000 ◽

Vol 99 (1) ◽

pp. 109-112 ◽

Cited By ~ 7

Author(s):

K. M. Gillespie ◽

C.-C. Szeto ◽

V. M. Betin ◽

P. W. Mathieson

Keyword(s):

Interleukin 12 ◽

T Helper ◽

T Helper 1 ◽

T Helper 2

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Role of IL-4, IL-13, and STAT6 in inflammation-induced hypercontractility of murine smooth muscle cells

AJP Gastrointestinal and Liver Physiology ◽

10.1152/ajpgi.2002.282.2.g226 ◽

2002 ◽

Vol 282 (2) ◽

pp. G226-G232 ◽

Cited By ~ 100

Author(s):

Hirotada Akiho ◽

Patricia Blennerhassett ◽

Yikang Deng ◽

Stephen M. Collins

Keyword(s):

Smooth Muscle ◽

Smooth Muscle Cells ◽

Trichinella Spiralis ◽

Muscle Cells ◽

Dependent Manner ◽

T Helper ◽

Concentration Dependent Manner ◽

T Helper 2 ◽

Muscularis Externa

T helper 2 (Th2) cytokines interleukin (IL)-4 and IL-13, which activate signal transducer and activator of transcription 6 (STAT6) are expressed in the muscularis externa during nematode infection and are candidate mediators of the associated hypercontractility. To determine the locus of action of these cytokines, we examined the IL-4- and IL-13-induced hypercontractility of the isolated muscle cells from STAT6 +/+ and STAT6 −/− mice. We compared the results with cells isolated from Trichinella spiralis-infected STAT6 +/+ and STAT6 −/− mice. Carbamylcholine chloride (Carbachol) induced the contraction of jejunal muscle cells in a concentration-dependent manner maximal contraction (Rmax26.7 ± 1.9%). Cells from T. spiralis-infected STAT6 −/− mice showed the hypertrophy (cell lengths 41.4 ± 0.8 to 89.0 ± 8.7 μm) and hypercontractility (Rmax37.5 ± 1.3%) induced by infection. IL-4Rα mRNA was detected in dispersed smooth muscle cells. Incubation of longitudinal muscle-myenteric plexus (LMMP) with IL-4 and IL-13 enhanced Carbachol-induced muscle contraction (Rmax35.5 ± 1.9 and 32.4 ± 2.9%, respectively). Incubation of LMMP from STAT6 −/− mice with IL-4 did not enhance the contraction. The hypercontractility in T. spiralis-infected mice was attenuated in STAT6 −/− mice ( P < 0.02). These results indicate both IL-4 and IL-13 induce hypercontractility of muscle cells via the STAT6 pathway, and this is the basis for hypercontractility observed in T. spiralis-infected mice.

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The Chitin Connection

mBio ◽

10.1128/mbio.00056-12 ◽

2012 ◽

Vol 3 (2) ◽

Cited By ~ 20

Author(s):

David L. Goldman ◽

Alfin G. Vicencio

Keyword(s):

Cell Wall ◽

Cell Membrane ◽

Fungal Infections ◽

Allergic Inflammation ◽

Chitinase Activity ◽

Chitin Deacetylase ◽

Fungal Cell ◽

Content Type ◽

Covalently Linked

ABSTRACTChitin, a polymer ofN-acetylglucosamine, is an essential component of the fungal cell wall. Chitosan, a deacetylated form of chitin, is also important in maintaining cell wall integrity and is essential forCryptococcus neoformansvirulence. In their article, Gilbert et al. [N. M. Gilbert, L. G. Baker, C. A. Specht, and J. K. Lodge, mBio 3(1):e00007-12, 2012] demonstrate that the enzyme responsible for chitosan synthesis, chitin deacetylase (CDA), is differentially attached to the cell membrane and wall. Bioactivity is localized to the cell membrane, where it is covalently linked via a glycosylphosphatidylinositol (GPI) anchor. Findings from this study significantly enhance our understanding of cryptococcal cell wall biology. Besides the role of chitin in supporting structural stability, chitin and host enzymes with chitinase activity have an important role in host defense and modifying the inflammatory response. Thus, chitin appears to provide a link between the fungus and host that involves both innate and adaptive immune responses. Recently, there has been increased attention to the role of chitinases in the pathogenesis of allergic inflammation, especially asthma. We review these findings and explore the possible connection between fungal infections, the induction of chitinases, and asthma.

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