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Krull F, Bleyer M, Schäfer J, Brenig B. A missense mutation in the highly conserved TNF-like domain of Ectodysplasin A is the candidate causative variant for X-linked hypohidrotic ectodermal dysplasia in Limousin cattle: Clinical, histological, and molecular analyses. PLoS One 2024; 19:e0291411. [PMID: 38252617 PMCID: PMC10802946 DOI: 10.1371/journal.pone.0291411] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2023] [Accepted: 08/29/2023] [Indexed: 01/24/2024] Open
Abstract
Ectodysplasin A related hypohidrotic ectodermal dysplasia (XLHED) is a well-studied fetal developmental disorder in mammals that mainly affects ectodermal structures. It has been identified in a variety of species, including mice, rats, dogs, cattle, and humans. Here, we report the clinical, histological, and molecular biological analyses of a case of XLHED in Limousin cattle. An affected Limousin calf showed pathognomonic signs of ectodermal dysplasia, i.e. sparse hair and characteristic dental aplasia. Histopathologic comparison of hairy and glabrous skin and computed tomography of the mandible confirmed the phenotypic diagnosis. In addition, a keratoconjunctivitis sicca was noted in one eye, which was also confirmed histopathologically. To identify the causative variant, we resequenced the bovine X-chromosomal ectodysplasin A gene (EDA) of the affected calf and compared the sequences to the bovine reference genome. A single missense variant (rs439722471) at position X:g.80411716T>C (ARS-UCD1.3) was identified. The variant resulted in an amino acid substitution from glutamic acid to glycine within the highly conserved TNF-like domain. To rule out the possibility that the variant was relatively common in the cattle population we genotyped 2,016 individuals including 40% Limousin cattle by fluorescence resonance energy transfer analysis. We also tested 5,116 multibreed samples from Run9 of the 1000 Bull Genomes Project for the said variant. The variant was not detected in any of the cattle tested, confirming the assumption that it was the causative variant. This is the first report of Ectodysplasin A related hypohidrotic ectodermal dysplasia in Limousin cattle and the description of a novel causal variant in cattle.
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Affiliation(s)
- Frederik Krull
- Institute of Veterinary Medicine, Georg-August University Goettingen, Goettingen, Germany
| | - Martina Bleyer
- German Primate Center, Pathology Unit, Goettingen, Germany
| | - Jana Schäfer
- Institute of Veterinary Medicine, Georg-August University Goettingen, Goettingen, Germany
| | - Bertram Brenig
- Institute of Veterinary Medicine, Georg-August University Goettingen, Goettingen, Germany
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Azar A, Bhutta MF, Del-Pozo J, Milne E, Cheeseman M. Trans-cortical vessels in the mouse temporal bulla bone are a means to recruit myeloid cells in chronic otitis media and limit peripheral leukogram changes. Front Genet 2022; 13:985214. [PMID: 36246635 PMCID: PMC9555619 DOI: 10.3389/fgene.2022.985214] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2022] [Accepted: 08/29/2022] [Indexed: 11/13/2022] Open
Abstract
Chronic otitis media, inflammation of the middle ear, is a sequel to acute otitis media in ∼8% of children. Chronic otitis media with effusion is the most common cause of childhood deafness and is characterised by effusion of white blood cells into the auditory bulla cavity. Skull flat bones have trans-cortical vessels which are responsible for the majority of blood flow in and out of the bone. In experimental models of stroke and aseptic meningitis there is preferential recruitment of myeloid cells (neutrophils and monocytes) from the marrow in skull flat bones. We report trans-cortical vessels in the mouse temporal bone connect to the bulla mucosal vasculature and potentially represent a means to recruit myeloid cells directly into the inflamed bulla. The mutant mouse strains Junbo (MecomJbo/+) and Jeff (Fbxo11Jf/+) develop chronic otitis spontaneously; MecomJbo/+ mice have highly cellular neutrophil (90%) rich bulla exudates whereas Fbxo11Jf/+ mice have low cellularity serous effusions (5% neutrophils) indicating differing demand for neutrophil recruitment. However we found peripheral leukograms of MecomJbo/+ and Fbxo11Jf/+ mice are similar to their respective wild-type littermate controls with healthy bullae and infer preferential mobilization of myeloid cells from temporal bulla bone marrow may mitigate the need for a systemic inflammatory reaction. The cytokines, chemokines and haematopoietic factors found in the inflamed bulla represent candidate signalling molecules for myeloid cell mobilization from temporal bone marrow. The density of white blood cells in the bulla cavity is positively correlated with extent of mucosal thickening in MecomJbo/+, Fbxo11Jf/+, and EdaTa mice and is accompanied by changes in epithelial populations and bone remodelling. In MecomJbo/+ mice there was a positive correlation between bulla cavity WBC numbers and total bacterial load. The degree of inflammation varies between contralateral bullae and between mutant mice of different ages suggesting inflammation may wax and wane and may be re-initiated by a new wave of bacterial infection. Clearance of white blood cells and inflammatory stimuli from the bulla cavity is impaired and this may create a pro-inflammatory feedback loop which further exacerbates otitis media and delays its resolution.
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Affiliation(s)
- Ali Azar
- Developmental Biology Division, Roslin Institute and The Royal (Dick) School of Veterinary Studies, University of Edinburgh, Edinburgh, Scotland, United Kingdom
| | - Mahmood F. Bhutta
- Brighton and Sussex Medical School, Brighton, United Kingdom
- Department of ENT, Royal Sussex County Hospital, Brighton, United Kingdom
| | - Jorge Del-Pozo
- Veterinary Pathology, The Royal (Dick) School of Veterinary Studies, University of Edinburgh, Edinburgh, Scotland, United Kingdom
| | - Elspeth Milne
- Veterinary Pathology, The Royal (Dick) School of Veterinary Studies, University of Edinburgh, Edinburgh, Scotland, United Kingdom
| | - Michael Cheeseman
- Developmental Biology Division, Roslin Institute and The Royal (Dick) School of Veterinary Studies, University of Edinburgh, Edinburgh, Scotland, United Kingdom
- Division of Pathology, Institute of Genetics and Molecular Medicine, University of Edinburgh, Edinburgh, Scotland, United Kingdom
- Centre for Comparative Pathology, Division of Pathology, Institute of Genetics and Molecular Medicine, University of Edinburgh, Edinburgh, Scotland, United Kingdom
- *Correspondence: Michael Cheeseman,
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Del-Pozo J, Headon DJ, Glover JD, Azar A, Schuepbach-Mallepell S, Bhutta MF, Riddell J, Maxwell S, Milne E, Schneider P, Cheeseman M. The EDA deficient mouse has Zymbal's gland hypoplasia and acute otitis externa. Dis Model Mech 2022; 15:274882. [PMID: 35107126 PMCID: PMC8990926 DOI: 10.1242/dmm.049034] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2021] [Accepted: 01/21/2022] [Indexed: 12/05/2022] Open
Abstract
In mice, rats, dogs and humans, the growth and function of sebaceous glands and eyelid Meibomian glands depend on the ectodysplasin signalling pathway. Mutation of genes encoding the ligand EDA, its transmembrane receptor EDAR and the intracellular signal transducer EDARADD leads to hypohidrotic ectodermal dysplasia, characterised by impaired development of teeth and hair, as well as cutaneous glands. The rodent ear canal has a large auditory sebaceous gland, the Zymbal’s gland, the function of which in the health of the ear canal has not been determined. We report that EDA-deficient mice, EDAR-deficient mice and EDARADD-deficient rats have Zymbal’s gland hypoplasia. EdaTa mice have 25% prevalence of otitis externa at postnatal day 21 and treatment with agonist anti-EDAR antibodies rescues Zymbal’s glands. The aetiopathogenesis of otitis externa involves infection with Gram-positive cocci, and dosing pregnant and lactating EdaTa females and pups with enrofloxacin reduces the prevalence of otitis externa. We infer that the deficit of sebum is the principal factor in predisposition to bacterial infection, and the EdaTa mouse is a potentially useful microbial challenge model for human acute otitis externa. Summary: Ectodysplasin-deficient mice have growth retardation of the auditory sebaceous Zymbal's gland and are predisposed to spontaneous bacterial infection of the outer ear canal by opportunistic pathogens.
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Affiliation(s)
- Jorge Del-Pozo
- Veterinary Pathology, The Royal (Dick) School of Veterinary Studies, University of Edinburgh, EH25 9RG, Scotland, UK
| | - Denis J Headon
- Roslin Institute and The Royal (Dick) School of Veterinary Studies, University of Edinburgh, EH25 9RG, Scotland, UK
| | - James D Glover
- Roslin Institute and The Royal (Dick) School of Veterinary Studies, University of Edinburgh, EH25 9RG, Scotland, UK
| | - Ali Azar
- Roslin Institute and The Royal (Dick) School of Veterinary Studies, University of Edinburgh, EH25 9RG, Scotland, UK
| | | | - Mahmood F Bhutta
- Department of ENT, Royal Sussex County Hospital, Brighton BN2 5BE, UK.,Brighton and Sussex Medical School, Falmer Brighton BN1 9PX, UK
| | - Jon Riddell
- Roslin Institute and The Royal (Dick) School of Veterinary Studies, University of Edinburgh, EH25 9RG, Scotland, UK
| | - Scott Maxwell
- Veterinary Pathology, The Royal (Dick) School of Veterinary Studies, University of Edinburgh, EH25 9RG, Scotland, UK
| | - Elspeth Milne
- Veterinary Pathology, The Royal (Dick) School of Veterinary Studies, University of Edinburgh, EH25 9RG, Scotland, UK
| | - Pascal Schneider
- Department of Biochemistry, University of Lausanne, Epalinges, Switzerland
| | - Michael Cheeseman
- Roslin Institute and The Royal (Dick) School of Veterinary Studies, University of Edinburgh, EH25 9RG, Scotland, UK.,Division of Pathology, University of Edinburgh, Institute of Genetics & Molecular Medicine, Crewe Road, Edinburgh, EH4 2XR, Scotland, UK.,Centre for Comparative Pathology, Division of Pathology, University of Edinburgh, Institute of Genetics & Molecular Medicine, Crewe Road, Edinburgh, EH4 2XR, Scotland, UK
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X-Linked Hypohidrotic Ectodermal Dysplasia in Crossbred Beef Cattle Due to a Large Deletion in EDA. Animals (Basel) 2021; 11:ani11030657. [PMID: 33801223 PMCID: PMC7999020 DOI: 10.3390/ani11030657] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2021] [Revised: 02/25/2021] [Accepted: 02/25/2021] [Indexed: 12/29/2022] Open
Abstract
Simple Summary Ectodermal dysplasias such as hypohidrotic ectodermal dysplasia (HED), are genetic conditions affecting the development and/or homeostasis of two or more ectodermal derivatives, including hair, teeth, nails, and eccrine glands. In particular, X-linked hypohidrotic ectodermal dysplasia-1 (ECTD1) in humans is characterized by a triad of signs comprising sparse hair, abnormal teeth, and anhidrosis or hypohidrosis. It has been reported in cattle, dogs, mice and rats. Until now, eight pathogenic variants in the bovine ectodysplasin A (EDA) gene causing ECTD1-like disorders have been found. Herein, five affected Red Angus-Simmental bull calves born over a 6-year period (2013–2019) in a single herd in the Western United States are reported showing an ECTD1-like syndrome. Calves were born with severe hypotrichosis and oligodontia. At age 1-week-old two calves died of severe pneumonia. Microscopic findings of the skin revealed small-caliber hair follicles with a mean density in flank skin slightly greater in affected animals than in control animals. Nasolabial, intranasal and tracheobronchial mucosal glands were absent, whereas olfactory glands were unaffected. Whole-genome sequencing (WGS) identified a 53 kb deletion of the X chromosome including parts of the EDA gene as well as the entire AWAT2 gene. The partial deletion of the EDA gene that is known to be associated with forms of ECTD1 is the most likely cause for the reported genodermatosis. Similar rare disorders in livestock are often not diagnosed at the molecular level due to lack of resources, short lifespan of the animals, and concerns for the producers’ reputation. Abstract X-linked hypohidrotic ectodermal dysplasia-1 (ECTD1) in people results in a spectrum of abnormalities, most importantly hypotrichosis, anodontia/oligodontia, and absent or defective ectodermally derived glands. Five Red Angus-Simmental calves born over a 6-year period demonstrated severe hypotrichosis and were diagnosed as affected with ECTD1-like syndrome. Two died of severe pneumonia within a week of birth. The skin of three affected calves revealed a predominance of histologically unremarkable small-caliber hair follicles. Larger follicles (>50 µm) containing medullated hairs (including guard and tactile hairs) were largely restricted to the muzzle, chin, tail, eyelids, tragus and distal portions of the limbs and tail. The mean histological density of hair follicles in flank skin of two affected calves was slightly greater than that in two unaffected calves. One affected calf was examined postmortem at 10 days of age to better characterize systemic lesions. Nasolabial, intranasal and tracheobronchial mucosal glands were absent, whereas olfactory glands were unaffected. Mandibular incisor teeth were absent. Premolar teeth were unerupted and widely spaced. Other than oligodontia, histological changes in teeth were modest, featuring multifocal disorganization of ameloblasts, new bone formation in dental alveoli, and small aggregates of osteodentin and cementum at the margins of the enamel organ. A 52,780 base pair deletion spanning six out of eight coding exons of EDA and all of AWAT2 was identified. Partial deletion of the EDA gene is the presumed basis for the reported X-chromosomal recessive inherited genodermatosis.
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Mozaffari M, Nash R, Tucker AS. Anatomy and Development of the Mammalian External Auditory Canal: Implications for Understanding Canal Disease and Deformity. Front Cell Dev Biol 2021; 8:617354. [PMID: 33553153 PMCID: PMC7857502 DOI: 10.3389/fcell.2020.617354] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2020] [Accepted: 12/11/2020] [Indexed: 12/15/2022] Open
Abstract
The mammalian ear is made up of three parts (the outer, middle, and inner ear), which work together to transmit sound waves into neuronal signals perceived by our auditory cortex as sound. This review focuses on the often-neglected outer ear, specifically the external auditory meatus (EAM), or ear canal. Within our complex hearing pathway, the ear canal is responsible for funneling sound waves toward the tympanic membrane (ear drum) and into the middle ear, and as such is a physical link between the tympanic membrane and the outside world. Unique anatomical adaptations, such as its migrating epithelium and cerumen glands, equip the ear canal for its function as both a conduit and a cul-de-sac. Defects in development, or later blockages in the canal, lead to congenital or acquired conductive hearing loss. Recent studies have built on decades-old knowledge of ear canal development and suggest a novel multi-stage, complex and integrated system of development, helping to explain the mechanisms underlying congenital canal atresia and stenosis. Here we review our current understanding of ear canal development; how this biological lumen is made; what determines its location; and how its structure is maintained throughout life. Together this knowledge allows clinical questions to be approached from a developmental biology perspective.
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Affiliation(s)
- Mona Mozaffari
- Centre for Craniofacial and Regenerative Biology, King's College London, Guy's Hospital, London, United Kingdom
| | - Robert Nash
- Department of Paediatric Otolaryngology, Cochlear Implants, Great Ormond Street Hospital for Children NHS Trust, London, United Kingdom
| | - Abigail S Tucker
- Centre for Craniofacial and Regenerative Biology, King's College London, Guy's Hospital, London, United Kingdom
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Abstract
Genetic deficiency of ectodysplasin A (EDA) causes X-linked hypohidrotic ectodermal dysplasia, a congenital condition characterized by the absence or abnormal formation of sweat glands, teeth, and several skin appendages. Stimulation of the EDA receptor (EDAR) with agonists in the form of recombinant EDA or anti-EDAR antibodies can compensate for the absence of Eda in a mouse model of Eda deficiency, provided that agonists are administered in a timely manner during fetal development. Here we provide detailed protocols for the administration of EDAR agonists or antagonists, or other proteins, by the intravenous, intraperitoneal, and intra-amniotic routes as well as protocols to collect blood, to visualize sweat gland function, and to prepare skulls in mice.
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Zhang L, Yang S, Huang L, Ho PCL. Poly (ethylene glycol)-block-poly (D, L-lactide) (PEG-PLA) micelles for brain delivery of baicalein through nasal route for potential treatment of neurodegenerative diseases due to oxidative stress and inflammation: An in vitro and in vivo study. Int J Pharm 2020; 591:119981. [PMID: 33069896 DOI: 10.1016/j.ijpharm.2020.119981] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2020] [Revised: 09/27/2020] [Accepted: 10/11/2020] [Indexed: 02/06/2023]
Abstract
The application of baicalein (BE) in central nervous system (CNS) neurodegenerative diseases is hampered by its poor solubility and low oral bioavailability despite its neuroprotective effects. In this study, BE was encapsulated into poly (ethylene glycol)-block-poly (D, L-lactide) micelles (BE-MC) and administrated through nasal inhalation to enhance its brain distribution. BE-MC showed comparable in-vitro antioxidant activity to BE solution. Cytotoxicity study illustrated BE-MC could reduce BE's toxicity in SH-SY5Y cells and BV-2 cells. BE solution at concentration higher than 5 µM caused significant BV-2 cells' death after stimulation of LPS while BE-MC were non-toxic to cells at concentrations up to 50 µM. BE solution at 5 µM had no anti-inflammatory effects in BV-2 cells while BE-MC could reduce the inflammatory factor TNF-α at 5 µM and IL-6 at 20 µM significantly. Pharmacokinetic studies in C57BL/6 mice showed the absolute AUC values of BE in plasma and brain of BE-MC through nasal inhalation group were 5.09-fold and 1.50-fold higher than that of BE coarse powder through oral administration group at the same dose. Thus, our study indicated BE-MC administered nasally could be useful for treatment of CNS neurodegenerative diseases due to oxidative stress and inflammation.
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Affiliation(s)
- Li Zhang
- NUS Graduate School for Integrative Sciences and Engineering, National University of Singapore, Singapore 117583, Singapore; Department of Pharmacy, Faculty of Science, National University of Singapore, Singapore 117543, Singapore
| | - Shili Yang
- Department of Pharmacy, Faculty of Science, National University of Singapore, Singapore 117543, Singapore
| | - Lizhen Huang
- School of Biology and Biological Engineering, South China University of Technology, Guangzhou 510006, China.
| | - Paul Chi-Lui Ho
- NUS Graduate School for Integrative Sciences and Engineering, National University of Singapore, Singapore 117583, Singapore; Department of Pharmacy, Faculty of Science, National University of Singapore, Singapore 117543, Singapore.
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Milne E, Nuttall T, Marioni-Henry K, Piccinelli C, Schwarz T, Azar A, Harris J, Duncan J, Cheeseman M. Cytological and microbiological characteristics of middle ear effusions in brachycephalic dogs. J Vet Intern Med 2020; 34:1454-1463. [PMID: 32407559 PMCID: PMC7379010 DOI: 10.1111/jvim.15792] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2019] [Revised: 04/14/2020] [Accepted: 04/28/2020] [Indexed: 12/20/2022] Open
Abstract
Background Middle ear effusion is common in brachycephalic dogs with similarities to otitis media with effusion in children. Association with the cranial and eustachian tube morphology and bacterial infection is suspected in both species. Hypothesis/objectives To determine cytological and bacteriological features of middle ear effusions in dogs, provide information on histological features, and further assess the dog as a model of the human disease. Animals Sixteen live dogs, 3 postmortem cases of middle ear effusion, and 2 postmortem controls. Methods Prospective; clinical investigation using computed tomography, magnetic resonance imaging, video‐otoscopy, myringotomy; cytological assessment of 30 and bacteriology of 28 effusions; histology and immunohistochemistry (CD3 for T‐lymphocytes, Pax5 for B lymphocytes and MAC387 for macrophages) of 10 middle ear sections. Results Effusions were associated with neurological deficits in 6/16 (38%) and concurrent atopic dermatitis and otitis externa in 9/16 (56%) of live cases. Neutrophils and macrophages predominated on cytology (median 60 [range 2%‐95.5%] and 27 [2%‐96.5%]) whether culture of effusions was positive or not. In histology sections, the mucosa was thickened in affected dogs but submucosal gland dilatation occurred in affected and unaffected dogs. There was no bacterial growth from 22/28 (79%) of effusions. Bacteria isolated from the other 6 (21%) were predominantly Staphylococcus pseudintermedius (4/6, 67%). Conclusions and Clinical Importance Clinical, morphological, and cytological findings in middle ear effusions of dogs and people suggest similar pathogeneses. Middle ear effusion of dogs could be a useful model of human otitis media with effusion. Such comparisons can improve understanding and management across species.
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Affiliation(s)
- Elspeth Milne
- Royal (Dick) School of Veterinary Studies and The Roslin Institute, The University of Edinburgh, Midlothian, United Kingdom
| | - Tim Nuttall
- Royal (Dick) School of Veterinary Studies and The Roslin Institute, The University of Edinburgh, Midlothian, United Kingdom
| | - Katia Marioni-Henry
- Royal (Dick) School of Veterinary Studies and The Roslin Institute, The University of Edinburgh, Midlothian, United Kingdom
| | - Chiara Piccinelli
- Royal (Dick) School of Veterinary Studies and The Roslin Institute, The University of Edinburgh, Midlothian, United Kingdom
| | - Tobias Schwarz
- Royal (Dick) School of Veterinary Studies and The Roslin Institute, The University of Edinburgh, Midlothian, United Kingdom
| | - Ali Azar
- MRC Centre for Regenerative Medicine, The University of Edinburgh, Edinburgh BioQuarter, Edinburgh, United Kingdom
| | - Jennifer Harris
- Royal (Dick) School of Veterinary Studies and The Roslin Institute, The University of Edinburgh, Midlothian, United Kingdom
| | - Juliet Duncan
- Royal (Dick) School of Veterinary Studies and The Roslin Institute, The University of Edinburgh, Midlothian, United Kingdom
| | - Michael Cheeseman
- Royal (Dick) School of Veterinary Studies and The Roslin Institute, The University of Edinburgh, Midlothian, United Kingdom.,Centre for Comparative Pathology & Division of Pathology , University of Edinburgh, Institute of Genetics and Molecular Medicine, Edinburgh, United Kingdom
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Geng R, Wang Q, Chen E, Zheng QY. Current Understanding of Host Genetics of Otitis Media. Front Genet 2020; 10:1395. [PMID: 32117425 PMCID: PMC7025460 DOI: 10.3389/fgene.2019.01395] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2019] [Accepted: 12/20/2019] [Indexed: 12/13/2022] Open
Abstract
The pathogenesis of otitis media (OM), an inflammatory disease of the middle ear (ME), involves interplay between many different factors, including the pathogenicity of infectious pathogens, host immunological status, environmental factors, and genetic predisposition, which is known to be a key determinant of OM susceptibility. Animal models and human genetics studies have identified many genes and gene variants associated with OM susceptibility: genes that encode components of multiple signaling pathways involved in host immunity and inflammatory responses of the ME mucosa; genes involved in cellular function, such as mucociliary transport, mucin production, and mucous cell metaplasia; and genes that are essential for Eustachian tube (ET) development, ME cavitation, and homeostasis. Since our last review, several new mouse models with mutations in genes such as CCL3, IL-17A, and Nisch have been reported. Moreover, genetic variants and polymorphisms in several genes, including FNDC1, FUT2, A2ML1, TGIF1, CD44, and IL1-RA variable number tandem repeat (VNTR) allele 2, have been identified as being significantly associated with OM. In this review, we focus on the current understanding of the role of host genetics in OM, including recent discoveries and future research prospects. Further studies on the genes identified thus far and the discovery of new genes using advanced technologies such as gene editing, next generation sequencing, and genome-wide association studies, will advance our understanding of the molecular mechanism underlying the pathogenesis of OM and provide new avenues for early screening and developing effective preventative and therapeutic strategies to treat OM.
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Affiliation(s)
- Ruishuang Geng
- College of Special Education, Binzhou Medical University, Yantai, China
| | - Qingzhu Wang
- College of Special Education, Binzhou Medical University, Yantai, China.,Department of Otolaryngology, Guangdong Second Provincial General Hospital, Guangzhou, China
| | - Eileen Chen
- Department of Otolaryngology, Case Western Reserve University, Cleveland, OH, United States
| | - Qing Yin Zheng
- Department of Otolaryngology, Case Western Reserve University, Cleveland, OH, United States
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