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Schmitt T, Waschke J. Autoantibody-Specific Signalling in Pemphigus. Front Med (Lausanne) 2021; 8:701809. [PMID: 34434944 PMCID: PMC8381052 DOI: 10.3389/fmed.2021.701809] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2021] [Accepted: 07/08/2021] [Indexed: 12/11/2022] Open
Abstract
Pemphigus is a severe autoimmune disease impairing barrier functions of epidermis and mucosa. Autoantibodies primarily target the desmosomal adhesion molecules desmoglein (Dsg) 1 and Dsg 3 and induce loss of desmosomal adhesion. Strikingly, autoantibody profiles in pemphigus correlate with clinical phenotypes. Mucosal-dominant pemphigus vulgaris (PV) is characterised by autoantibodies (PV-IgG) against Dsg3 whereas epidermal blistering in PV and pemphigus foliaceus (PF) is associated with autoantibodies against Dsg1. Therapy in pemphigus is evolving towards specific suppression of autoantibody formation and autoantibody depletion. Nevertheless, during the acute phase and relapses of the disease additional treatment options to stabilise desmosomes and thereby rescue keratinocyte adhesion would be beneficial. Therefore, the mechanisms by which autoantibodies interfere with adhesion of desmosomes need to be characterised in detail. Besides direct inhibition of Dsg adhesion, autoantibodies engage signalling pathways interfering with different steps of desmosome turn-over. With this respect, recent data indicate that autoantibodies induce separate signalling responses in keratinocytes via specific signalling complexes organised by Dsg1 and Dsg3 which transfer the signal of autoantibody binding into the cell. This hypothesis may also explain the different clinical pemphigus phenotypes.
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Affiliation(s)
- Thomas Schmitt
- Ludwig-Maximilian-Universität München, Anatomische Anstalt, Lehrstuhl Anatomie I - Vegetative Anatomie, Munich, Germany
| | - Jens Waschke
- Ludwig-Maximilian-Universität München, Anatomische Anstalt, Lehrstuhl Anatomie I - Vegetative Anatomie, Munich, Germany
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Kridin K, Schmidt E. Epidemiology of Pemphigus. JID INNOVATIONS 2021; 1:100004. [PMID: 34909708 PMCID: PMC8659392 DOI: 10.1016/j.xjidi.2021.100004] [Citation(s) in RCA: 37] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2020] [Revised: 01/26/2021] [Accepted: 01/26/2021] [Indexed: 01/01/2023] Open
Abstract
Pemphigus is an epidemiologically heterogeneous group of autoimmune bullous diseases comprising pemphigus vulgaris (PV), pemphigus foliaceus, paraneoplastic pemphigus, IgA pemphigus, and pemphigus herpetiformis. Recently, our knowledge about the frequency of pemphigus, which is highly variable between different populations, has considerably expanded, and the first non-HLA genes associated with PV have been identified. In addition, a variety of comorbidities, including other autoimmune diseases, hematological malignancies, and psoriasis, have been described in this variant. Here, initial data about the impact of COVID-19 on this fragile patient population are discussed and perspectives for future epidemiological studies are outlined.
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Key Words
- ACE, angiotensin-converting enzyme
- AIBD, autoimmune bullous disease
- CAAR, chimeric autoantibody receptor
- CI, confidence interval
- DSG, desmoglein
- EADV, European Academy of Dermatology and Venereology
- EC, extracellular
- EMA, European Medicines Agency
- FS, fogo selvage
- HR, hazard ratio
- ICD, International Classification of Diseases
- PF, pemphigus foliaceus
- PNP, paraneoplastic pemphigus
- PV, pemphigus vulgaris
- SMR, standardized mortality ratio
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Affiliation(s)
- Khalaf Kridin
- Lűbeck Institute of Experimental Dermatology, University of Lübeck, Lübeck, Germany
- The Azrieli Faculty of Medicine, Bar-Ilan University, Safed, Israel
| | - Enno Schmidt
- Lűbeck Institute of Experimental Dermatology, University of Lübeck, Lübeck, Germany
- Department of Dermatology, University of Lübeck, Lübeck, Germany
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Autoimmune bullous skin diseases, pemphigus and pemphigoid. J Allergy Clin Immunol 2020; 145:1031-1047. [DOI: 10.1016/j.jaci.2020.02.013] [Citation(s) in RCA: 50] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2020] [Revised: 02/19/2020] [Accepted: 02/20/2020] [Indexed: 02/07/2023]
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Abstract
Pemphigus forms a group of rare autoimmune bullous diseases that affect the skin and mucous membranes. This group has a chronic course leading to high morbidity and mortality. It is characterized by the production of pathogenic autoantibodies directed against different proteins of the desmosome, leading histologically to intraepidermal cleavage, and clinically to vesicles and erosions on the epithelium of the mucous membranes and/or the skin. The diagnosis of the subtype of pemphigus is based on clinical features, the level of histologic cleavage, and the identification of the antigens recognized by circulating autoantibodies by immunoserological analyses. The epidemiological features of pemphigus vary considerably in different regions of the world. Observational studies examining comorbidities and associations among patients with pemphigus are scarce and sometimes inconclusive. The prognosis, mortality, and clinical outcomes in pemphigus have undergone dramatic change throughout the years. This review provides a brief overview about the different subtypes of pemphigus: pemphigus vulgaris, pemphigus foliaceus, paraneoplastic pemphigus, pemphigus herpetiformis, and IgA pemphigus. In addition, it summarizes the most recent understanding of the epidemiology, mortality data, and comorbidities of this group of organ-specific autoimmune diseases.
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Ahmed AR, Carrozzo M, Caux F, Cirillo N, Dmochowski M, Alonso AE, Gniadecki R, Hertl M, López-Zabalza MJ, Lotti R, Pincelli C, Pittelkow M, Schmidt E, Sinha AA, Sprecher E, Grando SA. Monopathogenic vs multipathogenic explanations of pemphigus pathophysiology. Exp Dermatol 2018; 25:839-846. [PMID: 27305362 DOI: 10.1111/exd.13106] [Citation(s) in RCA: 56] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/02/2016] [Indexed: 01/31/2023]
Abstract
This viewpoint highlights major, partly controversial concepts about the pathogenesis of pemphigus. The monopathogenic theory explains intra-epidermal blistering through the "desmoglein (Dsg) compensation" hypothesis, according to which an antibody-dependent disabling of Dsg 1- and/or Dsg 3-mediated cell-cell attachments of keratinocytes (KCs) is sufficient to disrupt epidermal integrity and cause blistering. The multipathogenic theory explains intra-epidermal blistering through the "multiple hit" hypothesis stating that a simultaneous and synchronized inactivation of the physiological mechanisms regulating and/or mediating intercellular adhesion of KCs is necessary to disrupt epidermal integrity. The major premise for a multipathogenic theory is that a single type of autoantibody induces only reversible changes, so that affected KCs can recover due to a self-repair. The damage, however, becomes irreversible when the salvage pathway and/or other cell functions are altered by a partnering autoantibody and/or other pathogenic factors. Future studies are needed to (i) corroborate these findings, (ii) characterize in detail patient populations with non-Dsg-specific autoantibodies, and (iii) determine the extent of the contribution of non-Dsg antibodies in disease pathophysiology.
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Affiliation(s)
- A Razzaque Ahmed
- Department of Dermatology of Tufts University and Center for Blistering Diseases, Boston, MA, USA
| | - Marco Carrozzo
- School of Dental Sciences, University of Newcastle upon Tyne, Newcastle upon Tyne, UK
| | - Frédéric Caux
- Department of Dermatology, University Paris 13, Avicenne Hospital, APHP, Bobigny, France
| | - Nicola Cirillo
- Melbourne Dental School and Oral Health CRC, The University of Melbourne, Melbourne, Vic., Australia
| | - Marian Dmochowski
- Autoimmune Blistering Dermatoses Section, Department of Dermatology, Poznan University of Medical Sciences, Poznan, Poland
| | - Agustín España Alonso
- Department of Dermatology, School of Medicine, University Clinic of Navarra, University of Navarra, Navarra, Spain
| | - Robert Gniadecki
- Division of Dermatology, University of Alberta, Edmonton, AB, Canada
| | - Michael Hertl
- Department of Dermatology and Allergology, Philipps University, Marburg, Germany
| | | | - Roberta Lotti
- Department of Dermatology, University of Modena and Reggio Emilia, Modena, Italy
| | - Carlo Pincelli
- Department of Dermatology, University of Modena and Reggio Emilia, Modena, Italy
| | - Mark Pittelkow
- Department of Dermatology, Mayo Clinic, Scottsdale, AZ, USA
| | - Enno Schmidt
- Lübeck Institute of Experimental Dermatology (LIED), University of Lübeck, Lübeck, Germany
| | - Animesh A Sinha
- Department of Dermatology, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, Buffalo, NY, USA
| | - Eli Sprecher
- Department of Dermatology, Tel Aviv Medical Center, Tel Aviv, Israel
| | - Sergei A Grando
- Institute for Immunology and Departments of Dermatology and Biological Chemistry, University of California, Irvine, CA, USA.
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Timóteo RP, Silva MV, da Silva DAA, Catarino JDS, Alves FHC, Rodrigues Júnior V, Roselino AM, Sales-Campos H, Oliveira CJF. Cytokine and Chemokines Alterations in the Endemic Form of Pemphigus Foliaceus (Fogo Selvagem). Front Immunol 2017; 8:978. [PMID: 28855908 PMCID: PMC5557772 DOI: 10.3389/fimmu.2017.00978] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2017] [Accepted: 07/31/2017] [Indexed: 01/22/2023] Open
Abstract
INTRODUCTION The endemic form (fogo selvagem-FS) of pemphigus foliaceus is an autoimmune disease characterized by the presence of IgG autoantibodies against desmoglein-1. Despite the array of findings, the role of chemokines and cytokines that dictate the immune response and disease outcome is still poorly investigated. MATERIALS AND METHODS Serum from 64 patients diagnosed with FS was used to draw and establish the levels of these molecules on this disease and establish the levels of these molecules with the severity of FS, and influence of treatment. RESULTS In comparison to healthy subjects, FS patients, newly diagnosed and still without therapeutic intervention, had higher levels of IL-22 and CXCL-8, and reduced levels of IFN-γ, IL-2, IL-15, and CCL-11. Furthermore, treatment using immunosuppressant drugs augmented the production of IFN-γ, IL-2, CCL-5, and CCL-11 besides reducing the levels of IL-22 and CXCL-10. Immunosuppressive therapy seemed to have long-lasting effects on the production of higher amounts of IFN-γ, IL-2, and CCL-5, besides keeping lowered the levels of IL-22 in remission FS patients. CONCLUSION Taken together, our findings suggest a putative role of IL-22 in the pathogenesis of FS. Finally, data presented here may contribute for better understanding the immune aspects that control disease outcome.
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Affiliation(s)
- Rodolfo Pessato Timóteo
- Laboratory of Immunology, Institute of Natural and Biological Sciences, Federal University of Triângulo Mineiro, Uberaba, Brazil
| | - Marcos Vinicius Silva
- Laboratory of Immunology, Institute of Natural and Biological Sciences, Federal University of Triângulo Mineiro, Uberaba, Brazil
| | - Djalma Alexandre Alves da Silva
- Laboratory of Immunology, Institute of Natural and Biological Sciences, Federal University of Triângulo Mineiro, Uberaba, Brazil
| | - Jonatas Da Silva Catarino
- Laboratory of Immunology, Institute of Natural and Biological Sciences, Federal University of Triângulo Mineiro, Uberaba, Brazil
| | - Fernando Henrique Canhoto Alves
- Division of Dermatology, Department of Medical Clinics, Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto, Brazil
| | - Virmondes Rodrigues Júnior
- Laboratory of Immunology, Institute of Natural and Biological Sciences, Federal University of Triângulo Mineiro, Uberaba, Brazil
| | - Ana Maria Roselino
- Division of Dermatology, Department of Medical Clinics, Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto, Brazil
| | - Helioswilton Sales-Campos
- Laboratory of Immunology, Institute of Natural and Biological Sciences, Federal University of Triângulo Mineiro, Uberaba, Brazil
| | - Carlo José Freire Oliveira
- Laboratory of Immunology, Institute of Natural and Biological Sciences, Federal University of Triângulo Mineiro, Uberaba, Brazil
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Aoki V, Rivitti EA, Diaz LA. Update on fogo selvagem, an endemic form of pemphigus foliaceus. J Dermatol 2016; 42:18-26. [PMID: 25558948 DOI: 10.1111/1346-8138.12675] [Citation(s) in RCA: 61] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2014] [Accepted: 09/17/2014] [Indexed: 12/26/2022]
Abstract
Pemphigus are organ-specific autoimmune diseases, where autoantibodies (mainly immunoglobulin [Ig]G) directed against epidermal targets (glycoproteins of the desmosomal core) are detected. Endemic pemphigus foliaceus or fogo selvagem (FS) is one of the variants of pemphigus foliaceus pemphigus foliaceus that shares the same clinical and immunopathological features of the classic non-endemic pemphigus foliaceus form, including pathogenic IgG (mainly IgG4) autoantibodies directed against the ectodomain of desmoglein 1 (Dsg1), that lead to acantholysis. Pathogenesis of FS is complex, involving genetic, environmental and immunological factors. Human leukocyte antigen (HLA)-DRB1 alleles DRB1*0404, *1402, *1406 or *0102 have been previously identified as risk factors for FS (relative risk, >14). Individuals exposed to hematophagous insects are more susceptible to develop the disease. Non-pathogenic anti-Dsg1 antibodies of the IgG1 subclass, directed against the extracellular 5 domain of Dsg1, are detected in patients in the preclinical stage of the disease, and also in healthy controls living in endemic areas. In counterpart, patients with FS show pathogenic anti-Dsg1 IgG4 autoantibodies that bind the pathogenic extracellular 1 and 2 domains of Dsg1, emphasizing the intramolecular epitope-spreading hypothesis. A possible explanation for the development of the autoimmune process would be antigenic mimicry, initiated by environmental stimuli in those genetically predisposed individuals. Characterization of the pathogenesis of FS will allow the development of specific therapeutic targets, and the elucidation of other autoimmune processes.
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Affiliation(s)
- Valeria Aoki
- Department of Dermatology, University of São Paulo Medical School, São Paulo, Brazil
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Abstract
Pemphigus vulgaris (PV) is the most common type of pemphigus. PV pathogenesis is still debated, and treatment remains challenging. We investigated five controversial topics: (1) What are the target antigens in PV? (2) Do desmogleins adequately address PV pathophysiology? (3) How does acantholysis occur in PV? (4) Is PV still a lethal disease? (5) What is the role of rituximab (RTX) in PV treatment? Results from extensive literature searches suggested the following: (1) Target antigens of PV include a variety of molecules and receptors that are not physically compartmentalized within the epidermis. (2) PV is caused by a variety of autoantibodies to keratinocyte self-antigens, which concur to cause blistering by acting synergistically. (3) The concept of apoptolysis distinguishes the unique mechanism of autoantibody-induced keratinocyte damage in PV from other known forms of cell death. (4) PV remains potentially life-threatening largely because of treatment side effects, but it is uncertain which therapies carry the highest likelihood of lethal risk. (5) RTX is a very promising treatment option in patients with widespread recalcitrant or life-threatening PV. RTX's cost is an issue, its long-term side effects are still unknown, and randomized controlled trials are needed to establish the optimal dosing regimen.
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Affiliation(s)
- N Cirillo
- Department of Oral and Dental Sciences, University of Bristol, Bristol, UK.
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Abstract
The goal of contemporary research in pemphigus vulgaris and pemphigus foliaceus is to achieve and maintain clinical remission without corticosteroids. Recent advances of knowledge on pemphigus autoimmunity scrutinize old dogmas, resolve controversies, and open novel perspectives for treatment. Elucidation of intimate mechanisms of keratinocyte detachment and death in pemphigus has challenged the monopathogenic explanation of disease immunopathology. Over 50 organ-specific and non-organ-specific antigens can be targeted by pemphigus autoimmunity, including desmosomal cadherins and other adhesion molecules, PERP cholinergic and other cell membrane (CM) receptors, and mitochondrial proteins. The initial insult is sustained by the autoantibodies to the cell membrane receptor antigens triggering the intracellular signaling by Src, epidermal growth factor receptor kinase, protein kinases A and C, phospholipase C, mTOR, p38 MAPK, JNK, other tyrosine kinases, and calmodulin that cause basal cell shrinkage and ripping desmosomes off the CM. Autoantibodies synergize with effectors of apoptotic and oncotic pathways, serine proteases, and inflammatory cytokines to overcome the natural resistance and activate the cell death program in keratinocytes. The process of keratinocyte shrinkage/detachment and death via apoptosis/oncosis has been termed apoptolysis to emphasize that it is triggered by the same signal effectors and mediated by the same cell death enzymes. The natural course of pemphigus has improved due to a substantial progress in developing of the steroid-sparing therapies combining the immunosuppressive and direct anti-acantholytic effects. Further elucidation of the molecular mechanisms mediating immune dysregulation and apoptolysis in pemphigus should improve our understanding of disease pathogenesis and facilitate development of steroid-free treatment of patients.
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Affiliation(s)
- Sergei A Grando
- Department of Dermatology, University of California, Irvine, CA 92697, USA.
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Flores G, Qian Y, Díaz LA. The enigmatic autoimmune response in endemic pemphigus foliaceus. ACTAS DERMO-SIFILIOGRAFICAS 2010; 100 Suppl 2:40-8. [PMID: 20096161 DOI: 10.1016/s0001-7310(09)73377-0] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
Endemic pemphigus foliaceus, known as Fogo Selvagem (FS) in Brazil, is a disease characterized by subcorneal blisters and IgG4 anti-dermoglein 1 (Dsg1) autoantibodies. Epidemiological studies of FS strongly an environmental etiology. A 15-year surveillance of the Limao Verde Amerindian reservation in Brazil has uncovered information on the transition of the autoimmune response from the pre-clinical stage to disease state. This incubation time may evolve over several years. The serological markers of the pre-clinical state of FS are IgM anti-Dsg1, IgE and non-IgG4 autoantibodies against Dsg1. The disease stage of FS is characterized by the rise of pathogenic IgG4 anti-Dsg1 autoantibodies. In this review, the authors reviewed the literature on the relevance of the humoral autoimmune response of FS as well as the possible environmental triggers of anti-Dsg1 autoantibody formation. Based on epidemiological observations, the authors hypothesize that the pathogenic IgG4 response in FS may be triggered by hematophagous insect bites.
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Affiliation(s)
- G Flores
- Department of Dermatology, University of North Carolina School of Medicine, Chapel Hill, North Carolina, United States of America
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Culton DA, Qian Y, Li N, Rubenstein D, Aoki V, Filhio GH, Rivitti EA, Diaz LA. Advances in pemphigus and its endemic pemphigus foliaceus (Fogo Selvagem) phenotype: a paradigm of human autoimmunity. J Autoimmun 2008; 31:311-24. [PMID: 18838249 PMCID: PMC2704386 DOI: 10.1016/j.jaut.2008.08.003] [Citation(s) in RCA: 77] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2008] [Revised: 08/08/2008] [Accepted: 08/10/2008] [Indexed: 11/22/2022]
Abstract
Pemphigus encompasses a group of organ specific, antibody mediated autoimmune diseases of the skin characterized by keratinocyte detachment that leads to the development of blisters and erosions, which can become life-threatening. The pathogenic autoantibodies recognize desmogleins, which are members of the desmosomal cadherin family of cell adhesion molecules. Desmoglein 3 is targeted in pemphigus vulgaris while desmoglein 1 is targeted in pemphigus foliaceus and its endemic form, Fogo Selvagem. This review will briefly define the salient features of pemphigus and the proposed steps in pathogenesis. We will then summarize the most recent advances in three important areas of investigation: (i) epidemiologic, genetic, and immunologic features of Fogo Selvagem, (ii) molecular mechanisms of injury to the epidermis, and (iii) novel therapeutic strategies targeting specific steps in disease pathogenesis. The advances in each of these three seemingly separate areas contribute to the overall understanding of the pemphigus disease model. These recent advancements also underscore the dynamic interplay between the treatment of patients in a clinical setting and basic science research and have led to an integrative understanding of disease pathogenesis and treatment, allowing pemphigus to serve as a paradigm of human autoimmunity.
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Affiliation(s)
- Donna A. Culton
- Department of Dermatology, University of North Carolina at Chapel Hill, NC 27599, USA
| | - Ye Qian
- Department of Dermatology, University of North Carolina at Chapel Hill, NC 27599, USA
| | - Ning Li
- Department of Dermatology, University of North Carolina at Chapel Hill, NC 27599, USA
| | - David Rubenstein
- Department of Dermatology, University of North Carolina at Chapel Hill, NC 27599, USA
| | - Valeria Aoki
- Departamento de Dermatologia, Universidade de Sao Paulo, Brazil
| | - Gunter Hans Filhio
- Departamento de Dermatologia, Universidade Federal de Mato Grosso do Sul, Brazil
| | | | - Luis A. Diaz
- Department of Dermatology, University of North Carolina at Chapel Hill, NC 27599, USA
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Qaqish BF, Prisayanh P, Qian Y, Andraca E, Li N, Aoki V, Hans-Filho G, dos Santos V, Rivitti EA, Diaz LA. Development of an IgG4-based predictor of endemic pemphigus foliaceus (fogo selvagem). J Invest Dermatol 2008; 129:110-8. [PMID: 18704107 DOI: 10.1038/jid.2008.189] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
Fogo selvagem (FS) is mediated by pathogenic, predominantly IgG4, anti-desmoglein 1 (Dsg1) autoantibodies and is endemic in Limao Verde, Brazil. IgG and IgG subclass autoantibodies were tested in a sample of 214 FS patients and 261 healthy controls by Dsg1 ELISA. For model selection, the sample was randomly divided into training (50%), validation (25%), and test (25%) sets. Using the training and validation sets, IgG4 was chosen as the best predictor of FS, with index values above 6.43 classified as FS. Using the test set, IgG4 has sensitivity of 92% (95% confidence interval (95% CI): 82-95%), specificity of 97% (95% CI: 89-100%), and area under the curve of 0.97 (95% CI: 0.94-1.00). The IgG4 positive predictive value (PPV) in Limao Verde (3% FS prevalence) was 49%. The sensitivity, specificity, and PPV of IgG anti-Dsg1 were 87, 91, and 23%, respectively. The IgG4-based classifier was validated by testing 11 FS patients before and after clinical disease and 60 Japanese pemphigus foliaceus patients. It classified 21 of 96 normal individuals from a Limao Verde cohort as having FS serology. On the basis of its PPV, half of the 21 individuals may currently have preclinical FS and could develop clinical disease in the future. Identifying individuals during preclinical FS will enhance our ability to identify the etiological agent(s) triggering FS.
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Affiliation(s)
- Bahjat F Qaqish
- Department of Biostatisitcs, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, USA
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Aoki V, Lago F, Yamazaki MH, Santi CG, Maruta CW. Significado do epitope spreading na patogênese dos pênfigos vulgar e foliáceo. An Bras Dermatol 2008. [DOI: 10.1590/s0365-05962008000200010] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Os pênfigos são dermatoses bolhosas auto-imunes, em que há a produção de auto-anticorpos direcionados contra moléculas de adesão dos epitélios, levando à perda da coesão celular. A produção de auto-anticorpos ocorre quando os pacientes desenvolvem um desequilíbrio da resposta imune (quebra da tolerância imunológica), passando a reconhecer antígenos próprios. A resposta é geralmente direcionada contra um único epítopo alvo; entretanto, como conseqüência da resposta inflamatória do processo primário e do extenso dano tecidual ocasionado, pode haver exposição de componentes protéicos ocultos, levando à produção de diferentes auto-anticorpos. Assim, é possível que surja uma nova doença cutânea auto-imune, em decorrência do fenômeno intra ou intermolecular de epitope spreading. São revistos os principais conceitos desse fenômeno e sua ocorrência nas dermatoses bolhosas auto-imunes, com ênfase nos pênfigos, grupo de dermatoses bolhosas autoimunes mais prevalente no Brasil.
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Diaz LA, Prisayanh PS, Dasher DA, Li N, Evangelista F, Aoki V, Hans-Filho G, dos Santos V, Qaqish BF, Rivitti EA. The IgM anti-desmoglein 1 response distinguishes Brazilian pemphigus foliaceus (fogo selvagem) from other forms of pemphigus. J Invest Dermatol 2007; 128:667-75. [PMID: 17960181 DOI: 10.1038/sj.jid.5701121] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Fogo selvagem (FS) and pemphigus foliaceus (PF) possess pathogenic IgG anti-desmoglein 1-(Dsg1) autoantibodies. Although PF occurs sporadically, FS is endemic in Limao Verde (LV), Brazil (3.4% prevalence). IgM anti-Dsg1 were detected in 58% FS LV patients (n=31), 19% of FS patients from Hospital-Campo Grande (n=57), 19% from Hospital-Goiania (n=42), 12% from Hospital-Sao Paulo (n=56), 10% of PF patients from United States (n=20), and 0% of PF patients from Japan (n=20). Pemphigus vulgaris (n=40, USA and Japan), bullous pemphigoid (n=40, USA), and healthy donors (n=55, USA) showed negligible percentages of positive sera. High percentages of positive IgM anti-Dsg1 were found in healthy donors from four rural Amerindian populations (42% of 243) as compared with urban donors (14% of 81; P<0.001). More than 50% of healthy donors from LV (n=99, age 5-20 years) possess IgM anti-Dsg1 across ages, whereas IgG-anti-Dsg1 was detected in 2.9% (age 5-10 years), 7.3% (age 11-15 years), and 29% of donors above age 16. IgM anti-Dsg1 epitopes are Ca2+ and carbohydrate-independent. We propose that IgM anti-Dsg1 are common in FS patients in their native environment and uncommon in other pemphigus phenotypes and in FS patients who migrate to urban hospitals. Recurrent environmental antigenic exposure may lead to IgM and IgG responses that trigger FS. JID JOURNAL CLUB ARTICLE: For questions, answers, and open discussion about this article please go to http://network.nature.com/group/jidclub.
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Affiliation(s)
- Luis A Diaz
- Department of Dermatology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, USA.
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