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Clinical Reviews in Allergy & Immunology Dec 2019House dust mites are an unsurpassed cause of atopic sensitization and allergic illness throughout the world. The major allergenic dust mites Dermatophagoides... (Review)
Review
House dust mites are an unsurpassed cause of atopic sensitization and allergic illness throughout the world. The major allergenic dust mites Dermatophagoides pteronyssinus, Dermatophagoides farinae, Euroglyphus maynei, and Blomia tropicalis are eight-legged members of the Arachnid class. Their approximately 3-month lifespan comprises egg, larval, protonymph, tritonymph, and adult stages, with adults, about one fourth to one third of a millimeter in size, being at the threshold of visibility. The geographic and seasonal distributions of dust mites are determined by their need for adequate humidity, while their distribution within substrates is further determined by their avoidance of light. By contacting the epithelium of the eyes, nose, lower airways, skin, and gut, the allergen-containing particles of dust mites can induce sensitization and atopic symptoms in those organs. Various mite allergens, contained primarily in mite fecal particles but also in shed mite exoskeletons and decaying mite body fragments, have properties that include proteolytic activity, homology with the lipopolysaccharide-binding component of Toll-like receptor 4, homology with other invertebrate tropomyosins, and chitin-cleaving and chitin-binding activity. Mite proteases have direct epithelial effects including the breaching of tight junctions and the stimulation of protease-activated receptors, the latter inducing pruritus, epithelial dysfunction, and cytokine release. Other components, including chitin, unmethylated mite and bacterial DNA, and endotoxin, activate pattern recognition receptors of the innate immune system and act as adjuvants promoting sensitization to mite and other allergens. Clinical conditions resulting from mite sensitization and exposure include rhinitis, sinusitis, conjunctivitis, asthma, and atopic dermatitis. Systemic allergy symptoms can also occur from the ingestion of cross-reacting invertebrates, such as shrimp or snail, or from the accidental ingestion of mite-contaminated foods. Beyond their direct importance as a major allergen source, an understanding of dust mites leads to insights into the nature of atopy and of allergic sensitization in general.
Topics: Allergens; Animals; Antigens, Dermatophagoides; Humans; Hypersensitivity; Hypersensitivity, Immediate; Immunization; Population Dynamics; Pyroglyphidae
PubMed: 29936683
DOI: 10.1007/s12016-018-8693-0 -
The Journal of Allergy and Clinical... 2018
Topics: Animals; Dermatophagoides pteronyssinus; Pyroglyphidae
PubMed: 30033927
DOI: 10.1016/j.jaip.2018.04.029 -
The Journal of Allergy and Clinical... Jun 2022Infectious agents can reprogram or "train" macrophages and their progenitors to respond more readily to subsequent insults. However, whether such an inflammatory memory...
BACKGROUND
Infectious agents can reprogram or "train" macrophages and their progenitors to respond more readily to subsequent insults. However, whether such an inflammatory memory exists in type 2 inflammatory conditions such as allergic asthma was not known.
OBJECTIVE
We sought to decipher macrophage-trained immunity in allergic asthma.
METHODS
We used a combination of clinical sampling of house dust mite (HDM)-allergic patients, HDM-induced allergic airway inflammation in mice, and an in vitro training setup to analyze persistent changes in macrophage eicosanoid, cytokine, and chemokine production as well as the underlying metabolic and epigenetic mechanisms. Transcriptional and metabolic profiles of patient-derived and in vitro trained macrophages were assessed by RNA sequencing or metabolic flux analysis and liquid chromatography-tandem mass spectrometry analysis, respectively.
RESULTS
We found that macrophages differentiated from bone marrow or blood monocyte progenitors of HDM-allergic mice or asthma patients show inflammatory transcriptional reprogramming and excessive mediator (TNF-α, CCL17, leukotriene, PGE, IL-6) responses upon stimulation. Macrophages from HDM-allergic mice initially exhibited a type 2 imprint, which shifted toward a classical inflammatory training over time. HDM-induced allergic airway inflammation elicited a metabolically activated macrophage phenotype, producing high amounts of 2-hydroxyglutarate (2-HG). HDM-induced macrophage training in vitro was mediated by a formyl peptide receptor 2-TNF-2-HG-PGE/PGE receptor 2 axis, resulting in an M2-like macrophage phenotype with high CCL17 production. TNF blockade by etanercept or genetic ablation of Tnf in myeloid cells prevented the inflammatory imprinting of bone marrow-derived macrophages from HDM-allergic mice.
CONCLUSION
Allergen-triggered inflammation drives a TNF-dependent innate memory, which may perpetuate and exacerbate chronic type 2 airway inflammation and thus represents a target for asthma therapy.
Topics: Animals; Asthma; Dermatophagoides pteronyssinus; Disease Models, Animal; Humans; Hypersensitivity; Inflammation; Macrophages; Mice; Prostaglandins E; Pyroglyphidae
PubMed: 34974067
DOI: 10.1016/j.jaci.2021.11.026 -
Arerugi = [Allergy] 2022
Topics: Allergens; Animals; Humans; Pyroglyphidae; Rhinitis, Allergic; Sublingual Immunotherapy; Treatment Outcome
PubMed: 35296609
DOI: 10.15036/arerugi.71.92 -
MMW Fortschritte Der Medizin Aug 2023
Topics: Humans; Animals; Asthma; Pyroglyphidae
PubMed: 37537441
DOI: 10.1007/s15006-023-2830-2 -
The British Journal of Dermatology Aug 2023
Topics: Animals; Humans; Vitiligo; Pyroglyphidae; Keratinocytes; Skin; Hypopigmentation; Melanocytes
PubMed: 37405425
DOI: 10.1093/bjd/ljad200 -
Allergy Jun 2023Allergen source-derived proteases are a critical factor in the formation and development of asthma. The cysteine protease activity of house dust mite (HDM) disrupts the...
BACKGROUND
Allergen source-derived proteases are a critical factor in the formation and development of asthma. The cysteine protease activity of house dust mite (HDM) disrupts the epithelial barrier function. The expression of cystatin SN (CST1) is elevated in asthma epithelium. CST1 inhibits the cysteine protease activity. We aimed to elucidate the role of epithelium-derived CST1 in the development of asthma caused by HDM.
METHODS
CST1 protein levels in sputum supernatants and serum of patients with asthma and healthy volunteers were measured by ELISA. The ability of CST1 protein to suppress HDM-induced bronchial epithelial barrier function was examined in vitro. The effects of exogenous CST1 protein on abrogating HDM-induced epithelial barrier function and inflammation were examined in mice in vivo.
RESULTS
CST1 protein levels were higher in sputum supernatants (142.4 ± 8.95 vs 38.87 ± 6.85 ng/mL, P < 0.0001) and serum (1129 ± 73.82 vs 703.1 ± 57.02 pg/mL, P = 0.0035) in patients with asthma than in healthy subjects. The levels were significantly higher in patients with not well- and very poorly controlled asthma than those with well-controlled asthma. Sputum and serum CST1 protein levels were negatively correlated with lung function in asthma. CST1 protein levels were significantly lower in the serum of HDM-specific IgE (sIgE)-positive asthmatics than in sIgE-negative asthmatics. The HDM-induced epithelial barrier function disruption was suppressed by recombinant human CST1 protein (rhCST1) in vitro and in vivo.
CONCLUSION
Our data indicated that human CST1 protein suppresses asthma symptoms by protecting the asthmatic bronchial epithelial barrier through inhibiting allergenic protease activity. CST1 protein may serve as a potential biomarker for asthma control.
Topics: Humans; Mice; Animals; Pyroglyphidae; Salivary Cystatins; Asthma; Dermatophagoides pteronyssinus; Allergens; Epithelium; Peptide Hydrolases; Cysteine Proteases; Antigens, Dermatophagoides; Dust
PubMed: 37026502
DOI: 10.1111/all.15739 -
Adolescent Scalp Dermatitis Associated with Dermatophagoides spp. (Acariformes; Pyroglyphidae) Mite.Acta Parasitologica Sep 2022Dermatophagoides spp. (Acariformes; Pyroglyphidae), house dust-mite well known as the causative agent of atopic hypersensitivity and allergy could potentially cause...
PURPOSE
Dermatophagoides spp. (Acariformes; Pyroglyphidae), house dust-mite well known as the causative agent of atopic hypersensitivity and allergy could potentially cause severe dermatitis. Herein we report an uncommon case of scalp dermatitis associated with the presence of Dermatophagoides spp.
METHODS
A 17-year old male presented with patchy alopecia on the scalp without intense peeling or itching, surround by unchanged skin and hair. Initially, superficial fungal infection was suspected; however, parasitological examination revealed the presence of live mites.
RESULTS
All the anatomical measurements and parameters from the specimens were compatible with Dermatophagoides spp.
CONCLUSIONS
Dermatophagoides spp. are not yet confirmed as causative agents of parasitic infestation, but the presence of these mites could have caused an allergic reaction followed by dermatitis with mild-to-moderate clinical manifestations. However, true parasitism as well as phoresy could also be considered. The clinical manifestations caused by house-dust mite cannot be easily recognized and the lack of diagnostic tools is a hindrance that often leads to misdiagnosis and inadequate therapy.
Topics: Adolescent; Animals; Antigens, Dermatophagoides; Dermatitis; Humans; Male; Pyroglyphidae; Scalp; Skin
PubMed: 35536426
DOI: 10.1007/s11686-022-00561-1 -
Journal of Leukocyte Biology Sep 2018
Topics: Allergens; Animals; Asthma; Inflammation; Pyroglyphidae
PubMed: 30106490
DOI: 10.1002/JLB.3CE0718-293 -
Allergy and Asthma Proceedings Jul 2022Nineteen U.S. allergen extracts were standardized by the U.S. Food and Drug Administration (FDA) between 1987 and 1998, including of two house-dust mites, short ragweed,... (Review)
Review
Nineteen U.S. allergen extracts were standardized by the U.S. Food and Drug Administration (FDA) between 1987 and 1998, including of two house-dust mites, short ragweed, cat hair and cat pelt, seven temperate and one southern grass, and six Hymenoptera venom preparations. Relevant literature was reviewed. For each allergen, a "representative" extract was established; the potency of each representative extract was determined by measurement of the total protein content (Hymenoptera venom), radial diffusion measurement of the dominant allergen (short ragweed and cat), or, if there was no dominant allergen, then by quantitative skin testing by using the IDEAL (intradermal dilution for 50 mm sum of erythema determines the bioequivalent allergy units) method. In vitro tests were developed to allow the manufacturer to demonstrate that each lot of its extract was statistically identical, within defined limits, to the FDA reference extract. These tests included radial immunodiffusion, competitive enzyme-linked immunosorbent assay, and isoelectric focusing. The standardized extracts offer the advantage of consistent potency from lot to lot for each manufacturer and also from manufacturer to manufacturer, and assure the presence of recognized significant allergens within the extract. Therefore, standardized extracts offer improved safety and efficacy over their nonstandardized predecessors.
Topics: Allergens; Ambrosia; Animals; Arthropod Venoms; Cats; Desensitization, Immunologic; Humans; Plant Extracts; Poaceae; Pyroglyphidae
PubMed: 35818139
DOI: 10.2500/aap.2022.43.220015