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Macdougall JD, Thomas KO, Iweala OI. The Meat of the Matter: Understanding and Managing Alpha-Gal Syndrome. Immunotargets Ther 2022; 11:37-54. [PMID: 36134173 PMCID: PMC9484563 DOI: 10.2147/itt.s276872] [Citation(s) in RCA: 18] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2022] [Accepted: 09/02/2022] [Indexed: 11/23/2022] Open
Abstract
Alpha-gal syndrome is an unconventional food allergy, characterized by IgE-mediated hypersensitivity responses to the glycan galactose-alpha-1,3-galactose (alpha-gal) and not to a food-protein. In this review, we discuss how alpha-gal syndrome reframes our current conception of the mechanisms of pathogenesis of food allergy. The development of alpha-gal IgE is associated with tick bites though the possibility of other parasites promoting sensitization to alpha-gal remains. We review the immune cell populations involved in the sensitization and effector phases of alpha-gal syndrome and describe the current understanding of why allergic responses to ingested alpha-gal can be delayed by several hours. We review the foundation of management in alpha-gal syndrome, namely avoidance, but also discuss the use of antihistamines, mast cell stabilizers, and the emerging role of complementary and alternative therapies, biological products, and oral immunotherapy in the management of this condition. Alpha-gal syndrome influences the safety and tolerability of medications and medical devices containing or derived from mammalian products and impacts quality of life well beyond food choices.
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Affiliation(s)
- Jessica D Macdougall
- Department of Medicine, Thurston Arthritis Research Center, Division of Rheumatology, Allergy, and Immunology, Chapel Hill, NC, 27599, USA.,Department of Pediatrics, University of North Carolina Food Allergy Initiative, Division of Allergy and Immunology, University of North Carolina School of Medicine, Chapel Hill, NC, 27599, USA
| | - Kevin O Thomas
- Department of Medicine, Thurston Arthritis Research Center, Division of Rheumatology, Allergy, and Immunology, Chapel Hill, NC, 27599, USA.,Department of Pediatrics, University of North Carolina Food Allergy Initiative, Division of Allergy and Immunology, University of North Carolina School of Medicine, Chapel Hill, NC, 27599, USA
| | - Onyinye I Iweala
- Department of Medicine, Thurston Arthritis Research Center, Division of Rheumatology, Allergy, and Immunology, Chapel Hill, NC, 27599, USA.,Department of Pediatrics, University of North Carolina Food Allergy Initiative, Division of Allergy and Immunology, University of North Carolina School of Medicine, Chapel Hill, NC, 27599, USA
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2
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Carson AS, Gardner A, Iweala OI. Where's the Beef? Understanding Allergic Responses to Red Meat in Alpha-Gal Syndrome. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2022; 208:267-277. [PMID: 35017216 PMCID: PMC8928418 DOI: 10.4049/jimmunol.2100712] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/19/2021] [Accepted: 10/19/2021] [Indexed: 01/17/2023]
Abstract
Alpha-gal syndrome (AGS) describes a collection of symptoms associated with IgE-mediated hypersensitivity responses to the glycan galactose-alpha-1,3-galactose (alpha-gal). Individuals with AGS develop delayed hypersensitivity reactions, with symptoms occurring >2 h after consuming mammalian ("red") meat and other mammal-derived food products. The mechanisms of pathogenesis driving this paradigm-breaking food allergy are not fully understood. We review the role of tick bites in the development of alpha-gal-specific IgE and highlight innate and adaptive immune cells possibly involved in alpha-gal sensitization. We discuss the impact of alpha-gal glycosylation on digestion and metabolism of alpha-gal glycolipids and glycoproteins, and the implications for basophil and mast cell activation and mediator release that generate allergic symptoms in AGS.
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Affiliation(s)
- Audrey S. Carson
- Department of Medicine, Thurston Arthritis Research Center, Division of Rheumatology, Allergy, and Immunology,Department of Pediatrics, University of North Carolina Food Allergy Initiative, Division of Allergy and Immunology, University of North Carolina School of Medicine, Chapel Hill, NC, USA
| | - Aliyah Gardner
- Department of Medicine, Thurston Arthritis Research Center, Division of Rheumatology, Allergy, and Immunology,Department of Pediatrics, University of North Carolina Food Allergy Initiative, Division of Allergy and Immunology, University of North Carolina School of Medicine, Chapel Hill, NC, USA
| | - Onyinye I. Iweala
- Department of Medicine, Thurston Arthritis Research Center, Division of Rheumatology, Allergy, and Immunology,Department of Pediatrics, University of North Carolina Food Allergy Initiative, Division of Allergy and Immunology, University of North Carolina School of Medicine, Chapel Hill, NC, USA
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3
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Bansal RA, Bahal S, O'Brien R, Miller J, Bansal AS, Yong PF. The first reported cases of meat allergy following tick bites in the UK. JRSM Open 2021; 12:2054270421996131. [PMID: 33996105 DOI: 10.1177/2054270421996131] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Allergic reactions frequently involve the production of immunoglobulin E (IgE) antibodies to proteins. However, reactions directed against carbohydrate moieties are increasingly being recognised. Tick bites can contribute to the development of immunoglobulin E to the galactose-1,3-galactose (alpha-gal) moiety on tick salivary proteins. These IgE molecules can cross-react with alpha-gal found in red meats, causing Type I IgE-mediated hypersensitivity reactions to these foods. We present three cases of delayed reactions to beef, pork and lamb in patients with prior tick bites and in the presence of a positive-specific IgE to alpha-gal. Patients were advised to avoid red meat consumption and to carry emergency treatment in the form of anti-histamines with or without adrenaline autoinjector devices. This is the first published report of red meat allergy caused by tick bites suffered in the UK.
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Affiliation(s)
- Rhea A Bansal
- Immunology Department, Frimley Park Hospital, Frimley Health NHS Trust, Frimley GU16 7UJ, UK
| | - Sameer Bahal
- Immunology Department, The Royal Free Hospital, Royal Free London NHS Foundation Trust, London NW3 2QG, UK
| | - Rachael O'Brien
- Immunology Department, Frimley Park Hospital, Frimley Health NHS Trust, Frimley GU16 7UJ, UK
| | - Joanne Miller
- Immunology Department, Royal Surrey County Hospital, Royal Surrey NHS Foundation Trust, Surrey GU2 7XX, UK
| | | | - Patrick Fk Yong
- Immunology Department, Frimley Park Hospital, Frimley Health NHS Trust, Frimley GU16 7UJ, UK.,Immunology Department, Royal Surrey County Hospital, Royal Surrey NHS Foundation Trust, Surrey GU2 7XX, UK
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4
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Hils M, Wölbing F, Hilger C, Fischer J, Hoffard N, Biedermann T. The History of Carbohydrates in Type I Allergy. Front Immunol 2020; 11:586924. [PMID: 33163001 PMCID: PMC7583601 DOI: 10.3389/fimmu.2020.586924] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2020] [Accepted: 09/07/2020] [Indexed: 12/20/2022] Open
Abstract
Although first described decades ago, the relevance of carbohydrate specific antibodies as mediators of type I allergy had not been recognized until recently. Previously, allergen specific IgE antibodies binding to carbohydrate epitopes were considered to demonstrate a clinically irrelevant cross-reactivity. However, this changed following the discovery of type I allergies specifically mediated by oligosaccharide structures. Especially the emerging understanding of red meat allergy characterized by IgE directed to the oligosaccharide alpha-gal showed that carbohydrate-mediated reactions can result in life threatening systemic anaphylaxis which in contrast to former assumptions proves a high clinical relevance of some carbohydrate allergens. Within the scope of this review article, we illustrate the historical development of carbohydrate-allergen-research, reaching from only diagnostically relevant crossreactive-carbohydrate-determinants to clinically important antigens mediating type I allergy. Focusing on clinical and immunological features of the alpha-gal syndrome, we highlight the discovery of oligosaccharides as potentially highly immunogenic antigens and mediators of type I allergy, report what is known about the route of sensitization and the immunological mechanisms involved in sensitization and elicitation phase of allergic responses as well as currently available diagnostic and therapeutic tools. Finally, we briefly report on carbohydrates being involved in type I allergies different from alpha-gal.
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Affiliation(s)
- Miriam Hils
- Department of Dermatology and Allergy Biederstein, School of Medicine, Technical University of Munich, Munich, Germany
| | - Florian Wölbing
- Department of Dermatology and Allergy Biederstein, School of Medicine, Technical University of Munich, Munich, Germany
| | - Christiane Hilger
- Department of Infection and Immunity, Luxembourg Institute of Health (LIH), Esch-sur-Alzette, Luxembourg
| | - Jörg Fischer
- Department of Dermatology, Faculty of Medicine, Eberhard Karls University Tübingen, Tübingen, Germany
| | - Nils Hoffard
- Department of Dermatology and Allergy Biederstein, School of Medicine, Technical University of Munich, Munich, Germany
| | - Tilo Biedermann
- Department of Dermatology and Allergy Biederstein, School of Medicine, Technical University of Munich, Munich, Germany
- Clinical Unit Allergology, Helmholtz Zentrum München, German Research Center for Environmental 10 Health GmbH, Neuherberg, Germany
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5
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Rutkowski K, Wagner A, Rutkowski R, Sowa P, Pancewicz S, Moniuszko-Malinowska A. Alpha-gal syndrome: An emerging cause of food and drug allergy. Clin Exp Allergy 2020; 50:894-903. [PMID: 32542789 DOI: 10.1111/cea.13683] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2020] [Revised: 06/02/2020] [Accepted: 06/08/2020] [Indexed: 12/14/2022]
Abstract
Alpha-gal syndrome (AGS) describes a wide spectrum of hypersensitivity reactions mediated by specific IgE to the α-gal epitope (galactose-α-1,3-galactose) ubiquitously expressed on glycolipids/glycoproteins of most mammals. This fascinating new entity has completely changed the paradigms of allergy as allergic response is directed against an oligosaccharide and the reactions can be both immediate and delayed. They appear to be stimulated only by tick bites which induce production of α-gal specific IgE antibodies that lead to (at times fatal) hypersensitivity response. AGS is completely different to previously described anaphylaxis to tick saliva. It provides unique insight into the interplay between different arms of the immune system and the role of ectoparasites in the development of anaphylaxis to food and medication in patients at risk of tick bites including travellers. This review summarises recent advances in our understanding of its clinical presentation, pathomechanism and role of various tick species in the development of AGS.
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Affiliation(s)
| | - Annette Wagner
- Department of Adult Allergy, Guy's and St Thomas' Hospital, London, UK
| | - Ryszard Rutkowski
- Department of Respiratory Diagnostics and Bronchoscopy, Medical University of Bialystok, Bialystok, Poland
| | - Paweł Sowa
- Department of Population Medicine and Civilization Diseases Prevention, Medical University of Bialystok, Bialystok, Poland
| | - Sławomir Pancewicz
- Department of Infectious Diseases and Neuroinfections, Medical University of Bialystok, Bialystok, Poland
| | - Anna Moniuszko-Malinowska
- Department of Infectious Diseases and Neuroinfections, Medical University of Bialystok, Bialystok, Poland
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Platts-Mills TAE, Commins SP, Biedermann T, van Hage M, Levin M, Beck LA, Diuk-Wasser M, Jappe U, Apostolovic D, Minnicozzi M, Plaut M, Wilson JM. On the cause and consequences of IgE to galactose-α-1,3-galactose: A report from the National Institute of Allergy and Infectious Diseases Workshop on Understanding IgE-Mediated Mammalian Meat Allergy. J Allergy Clin Immunol 2020; 145:1061-1071. [PMID: 32057766 DOI: 10.1016/j.jaci.2020.01.047] [Citation(s) in RCA: 71] [Impact Index Per Article: 17.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2019] [Revised: 01/29/2020] [Accepted: 01/31/2020] [Indexed: 12/16/2022]
Abstract
The mammalian meat allergy known as the "α-Gal syndrome" relates to IgE specific for galactose-α-1,3-galactose (α-Gal), an oligosaccharide that is present in cells and tissues of nonprimate mammals. The recognition of delayed reactions to food derived from mammals in patients with IgE to α-Gal and also the association with tick bites have been increasing worldwide. In 2018, the National Institute of Allergy and Infectious Diseases, Division of Allergy, Immunology and Transplantation, sponsored a workshop on this emerging tick-related disease. International experts from the fields of tick biology, allergy, immunology, infectious disease, and dermatology discussed the current state of our understanding of this emerging medical condition. The participants provided suggestions for specific research priorities and for the development of resources to advance our knowledge of the mechanisms, diagnosis, management, and prevention of this allergic disease. This publication is a summary of the workshop and the panel's recommendations are presented herein.
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Affiliation(s)
| | - Scott P Commins
- Departments of Medicine & Pediatrics, University of North Carolina, Chapel Hill, NC
| | - Tilo Biedermann
- Department of Dermatology and Allergy, Technical University of Munich and Unit Clinical Allergology (EKA), Helmholtz Zentrum München, Munich, Germany
| | - Marianne van Hage
- Division of Immunology and Allergy, Department of Medicine Solna, Karolinska Institutet and University Hospital, Stockholm, Sweden
| | - Michael Levin
- Division of Paediatric Allergy, University of Cape Town, Cape Town, South Africa
| | - Lisa A Beck
- Department of Dermatology, University of Rochester Medical Center, Rochester, NY
| | - Maria Diuk-Wasser
- Department of Ecology, Evolution, and Environmental Biology, Columbia University, New York, NY
| | - Uta Jappe
- Division of Clinical and Molecular Allergology, Research Center Borstel, Airway Research, Center North (ARCN), Member of the German Center for Lung Research, Borstel, Germany; Interdisciplinary Allergy Outpatient Clinic, Department of Pneumology, University of Lübeck, Lübeck, Germany
| | - Danijela Apostolovic
- Division of Immunology and Allergy, Department of Medicine Solna, Karolinska Institutet and University Hospital, Stockholm, Sweden
| | - Michael Minnicozzi
- Division of Allergy, Immunology and Transplantation, Allergy, Asthma and Airway Biology Branch, National Institute of Allergy and Infectious Diseases, NIH, Rockville, Md
| | - Marshall Plaut
- Division of Allergy, Immunology and Transplantation, Allergy, Asthma and Airway Biology Branch, National Institute of Allergy and Infectious Diseases, NIH, Rockville, Md
| | - Jeffrey M Wilson
- Division of Allergy & Clinical Immunology, University of Virginia, Charlottesville, Va
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Levin M, Apostolovic D, Biedermann T, Commins SP, Iweala OI, Platts-Mills TAE, Savi E, van Hage M, Wilson JM. Galactose α-1,3-galactose phenotypes: Lessons from various patient populations. Ann Allergy Asthma Immunol 2019; 122:598-602. [PMID: 30922956 PMCID: PMC6839685 DOI: 10.1016/j.anai.2019.03.021] [Citation(s) in RCA: 52] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2019] [Revised: 03/13/2019] [Accepted: 03/15/2019] [Indexed: 12/23/2022]
Abstract
OBJECTIVE To review published studies on galactose α-1,3-galactose (α-gal), a carbohydrate epitope found on proteins and lipids in nonprimate mammals and present in foods (particularly organ or fat-rich red meat) and medications, where it causes delayed-onset and immediate-onset anaphylaxis. DATA SOURCES A literature search for the terms galactose α-1,3-galactose and α-gal using PubMed and Embase was performed. STUDY SELECTIONS Studies on α-gal were included in this review. RESULTS Several species of ticks contain α-gal epitopes and possibly salivary adjuvants that promote high titer sensitization and clinical reactivity. Risk factors for α-gal syndrome include exposure to ticks of particular species. Age and sex differences seen in various cohorts possibly reflect the prevalence of these exposures that vary according to setting. CONCLUSION The reason and mechanisms for delayed onset of food-related anaphylaxis and the preponderance of abdominal reactions are not clear but may involve the kinetics of allergen digestion and processing or immunologic presentation via a different mechanism from usual immediate-type food allergy.
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Affiliation(s)
- Michael Levin
- Division of Paediatric Allergy, University of Cape Town, Cape Town, South Africa.
| | - Danijela Apostolovic
- Division of Immunology and Allergy, Department of Medicine Solna, Karolinska Institutet and University Hospital, Stockholm, Sweden
| | - Tilo Biedermann
- Department of Dermatology and Allergy, Technical University of Munich, Munich, Germany
| | - Scott P Commins
- Departments of Medicine & Pediatrics, University of North Carolina, Chapel Hill, North Carolina
| | - Onyinye I Iweala
- Department of Medicine, Division of Rheumatology, Allergy, and Immunology, University of North Carolina, Chapel Hill, North Carolina
| | - Thomas A E Platts-Mills
- Division of Allergy & Clinical Immunology, University of Virginia, Charlottesville, Virginia
| | | | - Marianne van Hage
- Division of Immunology and Allergy, Department of Medicine Solna, Karolinska Institutet and University Hospital, Stockholm, Sweden
| | - Jeffrey M Wilson
- Division of Allergy & Clinical Immunology, University of Virginia, Charlottesville, Virginia
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Cabezas-Cruz A, Hodžić A, Román-Carrasco P, Mateos-Hernández L, Duscher GG, Sinha DK, Hemmer W, Swoboda I, Estrada-Peña A, de la Fuente J. Environmental and Molecular Drivers of the α-Gal Syndrome. Front Immunol 2019; 10:1210. [PMID: 31214181 PMCID: PMC6554561 DOI: 10.3389/fimmu.2019.01210] [Citation(s) in RCA: 70] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2019] [Accepted: 05/13/2019] [Indexed: 12/20/2022] Open
Abstract
The α-Gal syndrome (AGS) is a type of allergy characterized by an IgE antibody (Ab) response against the carbohydrate Galα1-3Galβ1-4GlcNAc-R (α-Gal), which is present in glycoproteins from tick saliva and tissues of non-catarrhine mammals. Recurrent tick bites induce high levels of anti-α-Gal IgE Abs that mediate delayed hypersensitivity to consumed red meat products in humans. This was the first evidence that tick glycoproteins play a major role in allergy development with the potential to cause fatal delayed anaphylaxis to α-Gal-containing foods and drugs and immediate anaphylaxis to tick bites. Initially, it was thought that the origin of tick-derived α-Gal was either residual blood meal mammalian glycoproteins containing α-Gal or tick gut bacteria producing this glycan. However, recently tick galactosyltransferases were shown to be involved in α-Gal synthesis with a role in tick and tick-borne pathogen life cycles. The tick-borne pathogen Anaplasma phagocytophilum increases the level of tick α-Gal, which potentially increases the risk of developing AGS after a bite by a pathogen-infected tick. Two mechanisms might explain the production of anti-α-Gal IgE Abs after tick bites. The first mechanism proposes that the α-Gal antigen on tick salivary proteins is presented to antigen-presenting cells and B-lymphocytes in the context of Th2 cell-mediated immunity induced by tick saliva. The second mechanism is based on the possibility that tick salivary prostaglandin E2 triggers Immunoglobulin class switching to anti-α-Gal IgE-producing B cells from preexisting mature B cells clones producing anti-α-Gal IgM and/or IgG. Importantly, blood group antigens influence the capacity of the immune system to produce anti-α-Gal Abs which in turn impacts individual susceptibility to AGS. The presence of blood type B reduces the capacity of the immune system to produce anti-α-Gal Abs, presumably due to tolerance to α-Gal, which is very similar in structure to blood group B antigen. Therefore, individuals with blood group B and reduced levels of anti-α-Gal Abs have lower risk to develop AGS. Specific immunity to tick α-Gal is linked to host immunity to tick bites. Basophil activation and release of histamine have been implicated in IgE-mediated acquired protective immunity to tick infestations and chronic itch. Basophil reactivity was also found to be higher in patients with AGS when compared to asymptomatic α-Gal sensitized individuals. In addition, host resistance to tick infestation is associated with resistance to tick-borne pathogen infection. Anti-α-Gal IgM and IgG Abs protect humans against vector-borne pathogens and blood group B individuals seem to be more susceptible to vector-borne diseases. The link between blood groups and anti-α-Gal immunity which in turn affects resistance to vector-borne pathogens and susceptibility to AGS, suggests a trade-off between susceptibility to AGS and protection to some infectious diseases. The understanding of the environmental and molecular drivers of the immune mechanisms involved in AGS is essential to developing tools for the diagnosis, control, and prevention of this growing health problem.
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Affiliation(s)
- Alejandro Cabezas-Cruz
- UMR BIPAR, INRA, ANSES, Ecole Nationale Vétérinaire d'Alfort, Université Paris-Est, Maisons-Alfort, France
| | - Adnan Hodžić
- Department of Pathobiology, Institute of Parasitology, University of Veterinary Medicine Vienna, Vienna, Austria
| | | | - Lourdes Mateos-Hernández
- UMR BIPAR, INRA, ANSES, Ecole Nationale Vétérinaire d'Alfort, Université Paris-Est, Maisons-Alfort, France
| | - Georg Gerhard Duscher
- Department of Pathobiology, Institute of Parasitology, University of Veterinary Medicine Vienna, Vienna, Austria
| | - Deepak Kumar Sinha
- Biology Center, Institute of Parasitology, Czech Academy of Sciences, Ceské Budějovice, Czechia
| | | | - Ines Swoboda
- Molecular Biotechnology Section, University of Applied Sciences, Vienna, Austria
| | | | - José de la Fuente
- SaBio, Instituto de Investigación de Recursos Cinegéticos, IREC-CSIC-UCLM-JCCM, Ciudad Real, Spain.,Department of Veterinary Pathobiology, Center for Veterinary Health Sciences, Oklahoma State University, Stillwater, OK, United States
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9
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Abstract
Immunoglobulin E (IgE), though constitutively present at low levels, is most commonly studied in atopic disease where it plays a vital role in mast cell degranulation and in initiating a T helper 2 (Th2) response. With the advent of better detection assays, however, researchers are discovering the importance of IgE in actively contributing to many disease states and pathologies. This review will discuss the latest findings in IgE beyond its role in allergies and recently discovered roles for IgE in its cell-bound form on FcεRI-expressing effector cells like monocytes and dendritic cells. In terms of parasites, we will discuss helminth-induced IgE that appears to protect the worms from immune recognition and a tick-borne illness that elicits an IgE response against red meat. Next, we describe recent findings of how auto-reactive IgE can contribute to the progression of lupus and induce organ damage. Finally, we summarize the emerging roles of IgE in tumor surveillance and antibody-dependent cytotoxicity. We additionally discuss recent or ongoing clinical trials that either target harmful IgE or use the unique characteristics of the isotype.
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Affiliation(s)
- Andrea J Luker
- Department of Microbiology and Immunology, Virginia Commonwealth University, Richmond, VA, USA
| | - Joseph C Lownik
- Department of Microbiology and Immunology, Virginia Commonwealth University, Richmond, VA, USA.,Center for Clinical and Translational Research, Virginia Commonwealth University, Richmond, VA, USA
| | - Daniel H Conrad
- Department of Microbiology and Immunology, Virginia Commonwealth University, Richmond, VA, USA
| | - Rebecca K Martin
- Department of Microbiology and Immunology, Virginia Commonwealth University, Richmond, VA, USA
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