RESUMEN
BACKGROUND: Pemphigus vulgaris (PV) and pemphigus foliaceus (PF) are potentially life-threatening autoimmune blistering diseases. Treatment is based on long-term immunosuppression with high doses of glucocorticosteroids in combination with potentially corticosteroid-sparing agents and/or rituximab. Immunoadsorption (IA) has emerged as a fast-acting adjuvant treatment option. OBJECTIVES: To assess the clinical efficacy of IA in addition to best medical treatment (BMT). METHODS: We conducted a multicentre (26 centres from Germany and Austria) randomized controlled trial in 72 patients with newly diagnosed, relapsed or chronic active PV or PF (34 female patients and 38 male patients, aged 42-72â years) comparing BMT (prednisolone 1.0â mg kg-1 per day plus azathioprine or mycophenolate) with adjuvant IA (BMT + IA). Central 1 : 1 randomization was done at the coordinating centre for clinical trials (KKS Marburg). The primary endpoint was analysed using Kaplan-Meier and Cox regression methods. RESULTS: The study was ended prematurely owing to safety concerns after random allocation of 72 patients to BMT + IA (n = 34) or BMT (n = 38). The primary endpoint, time to complete remission on therapy, was not significantly different for the two groups [hazard ratio (HR) 1.35, 95% confidence interval (CI) 0.68-2.69; P = 0.39]. The cumulative dose of prednisolone was significantly lower in the BMT + IA group compared with BMT alone (difference -1214, 95% CI -2225 to -70; P = 0.03). In a post hoc analysis, patients with more extensive PV/PF showed a tendency towards a shorter time to remission in the BMT + IA group compared with the BMT group (HR 1.87, P = 0.17 in patients with baseline Pemphigus Disease Area Index ≥ 15). While more adverse events were observed in patients in the BMT group (29 vs. 25), severe adverse events were more frequent in patients in the BMT + IA group (17 events in 10 patients vs. 11 events in 8 patients). CONCLUSIONS: In this study, adjuvant IA did not demonstrate a shorter time to clinical remission, but a corticosteroid-sparing effect was observed. In patients with extensive PV/PF, post hoc analysis suggests that adjuvant IA may lead to earlier remission, but potential adverse events must be carefully weighed against the expected benefits.
Pemphigus vulgaris and pemphigus foliaceus are potentially life-threatening autoantibody-driven blistering diseases, which present with erosions or blisters on skin and/or mucous membranes. Treatment is based on long-term immunosuppressive agents. Immunoadsorption (IA) is a procedure that removes autoantibodies from the blood and has emerged as a fast-acting treatment option for pemphigus.We conducted a trial comparing best medical treatment (BMT) (prednisolone 1.0 mg kg per day plus azathioprine or mycophenolate) with best medical treatment plus IA (BMT + IA). A total of 26 centres from Germany and Austria recruited 72 patients with active pemphigus (34 women and 38 men, aged 4272 years) who were randomly allocated in a ratio of 1 : 1 to the treatment groups.Following inclusion of 72 patients in the BMT + IA (n = 34) or BMT (n = 38) groups, the study ended prematurely owing to safety concerns. The main outcome, time to complete remission (relief of all symptoms) while still receiving therapy, was not significantly different for the two groups. In contrast, the cumulative dose of prednisolone was significantly lower in the BMT + IA compared with BMT alone. In an additional analysis, patients with more extensive pemphigus showed a tendency towards a shorter time to remission in the BMT + IA group compared with the BMT group. While more adverse events were observed in the BMT group (29 vs. 25), severe adverse events were more frequent in the BMT + IA group (17 vs. 11). In this study, IA did not show a shorter time to clinical remission, but a prednisolone-sparing effect was observed. In patients with extensive pemphigus, adjuvant IA may possibly lead to earlier remission, but potential adverse events must be carefully weighed against the expected benefits.
Asunto(s)
Pénfigo , Humanos , Masculino , Femenino , Inmunosupresores/uso terapéutico , Prednisolona/uso terapéutico , Rituximab/uso terapéutico , Adyuvantes Inmunológicos/uso terapéutico , Corticoesteroides/uso terapéuticoRESUMEN
BACKGROUND: TH2 cells were thought to be a pivotal factor for initiation of the autoimmune blistering disease pemphigus. However, the role of other T-cell subsets in pemphigus pathogenesis remained unclear. OBJECTIVE: We aimed to characterize the exact phenotype of T cells responsible for the development of pemphigus. METHODS: Whole transcriptome shotgun sequencing was performed to determine differential gene expression in pemphigus lesions and skin of healthy individuals. The cutaneous cytokine signature was further evaluated by real-time quantitative PCR. In peripheral blood, the distribution of TH cell and folliclular helper (TFH) cell subsets was analyzed by flow cytometry. Finally, the capacity of TH and TFH cell subsets to induce desmoglein (Dsg)-specific autoantibodies by memory B cells was evaluated in coculture experiments. RESULTS: Transcriptome analysis of skin samples identified an IL-17A-dominated immune signature in patients with pemphigus, and Kyoto Encyclopedia of Genes and Genomes pathway analysis confirmed the dominance of the IL-17A signaling pathway. Increased expression of IL17A and associated cytokines was also detected by real-time quantitative PCR comparing lesional with perilesional or healthy skin. Interestingly, utilization of flow cytometry showed that patients with active pemphigus had elevated levels of circulating IL-17+, TH17, TFH17, and TFH17.1 cells. Notably, levels of TH17 and TFH17 cells correlated with levels of Dsg-specific CD19+CD27+ memory B cells, and patients with acute pemphigus showed higher levels of Dsg3-autoreactive TFH17 cells. Coculture experiments revealed TFH17 cells as primarily responsible for inducing Dsg-specific autoantibody production by B cells. CONCLUSION: Our findings show that TFH17 cells are critically involved in the pathogenesis of pemphigus and offer novel targets for therapeutic intervention.
Asunto(s)
Autoanticuerpos/inmunología , Desmogleína 1/inmunología , Desmogleína 3/inmunología , Pénfigo/inmunología , Pénfigo/metabolismo , Células Th17/inmunología , Células Th17/metabolismo , Enfermedades Autoinmunes/inmunología , Enfermedades Autoinmunes/metabolismo , Autoinmunidad , Linfocitos B/inmunología , Linfocitos B/metabolismo , Biomarcadores , Humanos , Inmunofenotipificación , Piel/inmunología , Piel/metabolismo , Piel/patología , Subgrupos de Linfocitos T/inmunología , Subgrupos de Linfocitos T/metabolismoRESUMEN
BACKGROUND AND OBJECTIVES: Pemphigus diseases are potentially life-threatening and rare autoimmune bullous disorders characterized by blisters and erosions of the skin and mucous membranes. These disorders can be largely divided into two major subtypes: pemphigus vulgaris (PV) and pemphigus foliaceus (PF). The objective of this study was to evaluate the autoantibody profile and response to therapy of PV and PF patients by analyzing the clinicopathological data from a registry for bullous autoimmune dermatoses. PATIENTS AND METHODS: In a retrospective study, data from 69 patients with PV and PF were included in the analysis. The Autoimmune Bullous Skin Intensity Score (ABSIS) was used to assess the clinical course, remissions, relapses and severity of the disease at first manifestation and throughout the observation period. ELISA was performed to assess levels of anti-desmoglein (Dsg)-1 and anti-Dsg3 IgG serum autoantibodies. RESULTS: The mean remission time in PV and PF patients was 63 weeks. PV patients with mucosal involvement showed a more favorable healing process. In PV patients with a moderate/high anti-Dsg1 IgG serum level at baseline, anti-Dsg3 IgG levels decreased during the observation period. CONCLUSIONS: Our study provides additional insights into the clinical course of patients with PV and PF, revealing that a mucosal phenotype is associated with a higher tendency towards remission.
Asunto(s)
Enfermedades Autoinmunes , Pénfigo , Autoanticuerpos , Desmogleína 1 , Desmogleína 3 , Progresión de la Enfermedad , Ensayo de Inmunoadsorción Enzimática , Humanos , Inmunoglobulina G , Pénfigo/diagnóstico , Pénfigo/tratamiento farmacológico , Sistema de Registros , Estudios RetrospectivosRESUMEN
HINTERGRUND UND ZIELE: Pemphigus gehört zu den seltenen, aber potentiell lebensbedrohlichen Autoimmunerkrankungen. Typisch sind Blasen und Erosionen der Haut und der Schleimhäute. Grundsätzlich unterscheiden wir zwei Subtypen: Pemphigus vulgaris (PV) und Pemphigus foliaceus (PF). In dieser Studie wurden die klinisch-pathologischen Daten aus einem Register für bullöse Autoimmundermatosen analysiert mit dem Ziel, das Autoantikörperprofil und das Therapieansprechen bei Patienten mit PV und PF genauer zu charakterisieren. PATIENTEN UND METHODEN: In einer retrospektiven Studie wurden die Daten von 69 Patienten mit PV und PF analysiert. Zur Beurteilung des klinischen Verlaufs, der Remissionen und Rezidive sowie des Schweregrads der Krankheit bei Erstmanifestation und während des gesamten Beobachtungszeitraums diente der ABSIS (Autoimmune Bullous Skin Intensity Score) (ABSIS). Mittels ELISA wurden die Spiegel von Anti-Desmoglein (Dsg)-1- und Anti-Dsg- IgG-Autoantikörpern im Serum bestimmt. ERGEBNISSE: Die mittlere Remissionszeit bei Patienten mit PV und PF betrug 63 Wochen. PV-Patienten mit Schleimhautbeteiligung zeigten eine schnellere Heilung. Bei PV-Patienten mit moderat oder stark erhöhten Anti-Dsg1-IgG-Autoantikörpern im Serum zu Beginn erfolgte im Lauf des Beobachtungszeitraums ein Absinken der Anti-Dsg3-IgG-Spiegel. SCHLUSSFOLGERUNGEN: Unsere Studie liefert neue Erkenntnisse zum Krankheitsverlauf bei Patienten mit PV und PF und offenbart, dass ein Phänotyp mit Schleimhautbeteiligung eine stärkere Neigung zur Remission aufweist.
RESUMEN
BACKGROUND: Several European countries recently developed international diagnostic and management guidelines for pemphigus, which have been instrumental in the standardization of pemphigus management. OBJECTIVE: We now present results from a subsequent Delphi consensus to broaden the generalizability of the recommendations. METHODS: A preliminary survey, based on the European Dermatology Forum and the European Academy of Dermatology and Venereology guidelines, was sent to a panel of international experts to determine the level of consensus. The results were discussed at the International Bullous Diseases Consensus Group in March 2016 during the annual American Academy of Dermatology conference. Following the meeting, a second survey was sent to more experts to achieve greater international consensus. RESULTS: The 39 experts participated in the first round of the Delphi survey, and 54 experts from 21 countries completed the second round. The number of statements in the survey was reduced from 175 topics in Delphi I to 24 topics in Delphi II on the basis of Delphi results and meeting discussion. LIMITATIONS: Each recommendation represents the majority opinion and therefore may not reflect all possible treatment options available. CONCLUSIONS: We present here the recommendations resulting from this Delphi process. This international consensus includes intravenous CD20 inhibitors as a first-line therapy option for moderate-to-severe pemphigus.
Asunto(s)
Factores Inmunológicos/administración & dosificación , Pénfigo/diagnóstico , Pénfigo/terapia , Plasmaféresis , Guías de Práctica Clínica como Asunto , Academias e Institutos/normas , Administración Intravenosa , Antígenos CD20/inmunología , Terapia Combinada/métodos , Terapia Combinada/normas , Consenso , Técnica Delphi , Dermatología/métodos , Dermatología/normas , Quimioterapia Combinada/métodos , Quimioterapia Combinada/normas , Europa (Continente) , Glucocorticoides/administración & dosificación , Humanos , Pénfigo/inmunología , Rituximab/administración & dosificación , Índice de Severidad de la EnfermedadRESUMEN
Skin manifestations of systemic disease and malignancy are extremely polymorphous. Clinicians should be familiarized with paraneoplastic dermatoses in order to perform an early diagnosis of the underlying neoplasm. Lack of familiarity with cutaneous clues of internal malignancy may delay diagnosis and treatment of cancer. In this review, we described several paraneoplastic dermatoses and discussed extensively two paradigmatic ones, namely paraneoplastic pemphigus and paraneoplastic dermatomyositis.
Asunto(s)
Dermatomiositis/fisiopatología , Neoplasias/diagnóstico , Síndromes Paraneoplásicos/diagnóstico , Pénfigo/fisiopatología , Piel/patología , Citocinas/metabolismo , Dermatomiositis/metabolismo , Dermatomiositis/patología , Eritema/metabolismo , Eritema/patología , Eritema/fisiopatología , Humanos , Neoplasias/metabolismo , Neoplasias/fisiopatología , Síndromes Paraneoplásicos/metabolismo , Síndromes Paraneoplásicos/fisiopatología , Pénfigo/metabolismo , Pénfigo/patología , Piodermia Gangrenosa/metabolismo , Piodermia Gangrenosa/patología , Piodermia Gangrenosa/fisiopatología , Piel/metabolismo , Enfermedades de la Piel/metabolismo , Enfermedades de la Piel/patología , Enfermedades de la Piel/fisiopatología , Síndrome de Sweet/metabolismo , Síndrome de Sweet/patología , Síndrome de Sweet/fisiopatologíaRESUMEN
BACKGROUND AND OBJECTIVES: Treatment of severe dermatological autoimmune diseases and toxic epidermal necrolysis (TEN) with high-dose intravenous immunoglobulin (IVIg) is a well-established procedure in dermatology. As treatment with IVIg is usually considered for rare clinical entities or severe cases, the use of immunoglobulin is not generally based on data from randomized controlled trials usually required for evidence-based medicine. Since the indications for the use of IVIg are rare, it is unlikely that such studies will be available in the foreseeable future. Because first-line use is limited by the high costs of IVIg, the first clinical guidelines on the use of IVIg in dermatological conditions were established in 2008 and renewed in 2011. METHODS: The European guidelines presented here were prepared by a panel of experts nominated by the European Dermatology Forum (EDF) and European Academy of Dermatology and Venereology (EADV). The guidelines were developed to update the indications for treatment currently considered effective and to summarize the evidence for the use of IVIg in dermatological autoimmune diseases and TEN. RESULTS AND CONCLUSION: The current guidelines represent consensual expert opinions and definitions on the use of IVIg reflecting current published evidence and are intended to serve as a decision-making tool for the use of IVIg in dermatological diseases.
Asunto(s)
Enfermedades Autoinmunes/tratamiento farmacológico , Dermatología/normas , Inmunoglobulinas Intravenosas/administración & dosificación , Guías de Práctica Clínica como Asunto , Enfermedades de la Piel/tratamiento farmacológico , Enfermedades Autoinmunes/diagnóstico , Dermatología/métodos , Relación Dosis-Respuesta a Droga , Europa (Continente) , Humanos , Inmunoglobulinas Intravenosas/uso terapéutico , Enfermedades de la Piel/diagnóstico , Síndrome de Stevens-JohnsonRESUMEN
Pemphigus Vulgaris is an autoimmune disease that results in blister formation in the epidermis and in mucosal tissues due to antibodies recognizing desmosomal cadherins, mainly desmoglein-3 and -1. Studies on the molecular mechanisms of Pemphigus have mainly been carried out using the spontaneously immortalized human keratinocyte cell line HaCaT or in primary keratinocytes. However, both cell systems have suboptimal features, with HaCaT cells exhibiting a large number of chromosomal aberrations and mutated p53 tumor suppressor, whereas primary keratinocytes are short-lived, heterogeneous and not susceptible to genetic modifications due to their restricted life-span. We have here tested the suitability of the commercially available human keratinocyte cell line hTert/KER-CT as a model system for research on epidermal cell adhesion and Pemphigus pathomechanisms. We here show that hTert cells exhibit a calcium dependent expression of desmosomal cadherins and are well suitable for typical assays used for studies on Pemphigus, such as sequential detergent extraction and Dispase-based dissociation assay. Treatment with Pemphigus auto-antibodies results in loss of monolayer integrity and altered localization of desmoglein-3, as well as loss of colocalization with flotillin-2. Our findings demonstrate that hTert cells are well suitable for studies on epidermal cell adhesion and Pemphigus pathomechanisms.
Asunto(s)
Desmosomas/genética , Desmosomas/metabolismo , Queratinocitos/metabolismo , Pénfigo/etiología , Pénfigo/metabolismo , Telomerasa/genética , Autoanticuerpos/inmunología , Biomarcadores , Adhesión Celular , Línea Celular , Línea Celular Transformada , Desmosomas/inmunología , Técnica del Anticuerpo Fluorescente , Expresión Génica , Humanos , Queratinocitos/inmunología , Modelos Biológicos , Pénfigo/patologíaAsunto(s)
Epidermólisis Ampollosa Adquirida , Epidermólisis Ampollosa , Hemofilia A , Verrugas , Humanos , Epidermólisis Ampollosa Adquirida/complicaciones , Epidermólisis Ampollosa Adquirida/diagnóstico , Hemofilia A/complicaciones , Hemofilia A/diagnóstico , Piel , Verrugas/complicaciones , Verrugas/diagnósticoRESUMEN
Pemphigus vulgaris (PV) is a severe autoimmune blistering disease of the skin and mucous membranes. As autoantibodies play an essential role in the disease pathogenesis, the serological detection of anti-desmoglein 3 IgG represents a central tool in the diagnosis of the disease. In this study, we show the validation of a novel lateral flow immunoassay (LFIA) which rapidly detects anti-desmoglein 3 (Dsg3) IgG in human serum. In contrast to other diagnostic procedures, the assay is compact and simple to perform and delivers a fast "yes" or "no" answer within 10 minutes without additional hardware requirements for test evaluation. For validation, a blinded collection of 200 sera including 100 sera from 14 PV patients, 75 sera from 24 bullous pemphigoid patients and 25 sera from 6 patients with pemphigus foliaceus collected at different time points during disease was used. Presence or non-presence of anti-Dsg3 IgG within sera was confirmed using a commercially available Dsg3-ELISA. For qualitative evaluation, Dsg3-LFIA test results were assessed by two independent groups of human observers. Furthermore, quantitative evaluation using POCScan reader was applied. The Dsg3-LFIA demonstrated reliable test results with a sensitivity and specificity of 78.1% and 97.1%, respectively. Test results from POCScan and human observers showed a substantial agreement. The Dsg3-LFIA represents a new diagnostic tool for the immediate and reliable detection of anti-desmoglein 3 serum IgG autoantibodies that does not require additional hardware. Further prospective trials are warranted to validate the Dsg3 LFIA in pemphigus.
Asunto(s)
Autoanticuerpos/sangre , Desmogleína 3/inmunología , Inmunoensayo/métodos , Inmunoglobulina G/sangre , Pénfigo/sangre , Pénfigo/diagnóstico , Humanos , Penfigoide Ampolloso/sangre , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Método Simple Ciego , Factores de TiempoRESUMEN
Pathophysiologically, bullous autoimmune dermatoses are caused by autoantibodies directed against adhesion molecules or structural proteins of the skin and mucous membranes, clinically resulting in blister formation. Depending on the respective target proteins of the autoimmune response and their location in the skin, a distinction is made between intraepidermal (pemphigus disorders), junctional (pemphigoid disorders), and subepidermal (epidermolysis bullosa acquisita, dermatitis herpetiformis) autoimmune blistering diseases. The most common bullous autoimmune dermatosis, bullous pemphigoid is characterized by marked clinical variability and intense pruritus. Predominantly affecting elderly individuals, there has been a significant increase in its incidence in recent years. While mucosal lesions occur in less than 30 % of bullous pemphigoid patients, the second most common bullous autoimmune dermatosis, pemphigus vulgaris, typically presents with oral erosions as the predominant and - frequently - initial symptom. Its onset is usually in the 4th to 6th decade of life. Scarring is typically found in subepidermal blistering disorders such as epidermolysis bullosa acquisita or mucous membrane pemphigoid. Diagnosis is based on clinical and histological findings as well as direct and indirect immunofluorescence and detection of circulating autoantibodies. Although a number of controlled clinical trials have been conducted in recent years, treatment of bullous autoimmune disorders is still primarily based on clinical experience. Therapeutic options include topical and systemic corticosteroids as well as adjuvant immunosuppressants. Recalcitrant cases may require treatment with immunoadsorption, intravenous immunoglobulins, or the monoclonal anti-CD20 antibody rituximab.
Asunto(s)
Enfermedades Autoinmunes , Epidermólisis Ampollosa Adquirida , Penfigoide Ampolloso , Enfermedades Cutáneas Vesiculoampollosas , Anticuerpos Monoclonales/uso terapéutico , Enfermedades Autoinmunes/diagnóstico , Enfermedades Autoinmunes/tratamiento farmacológico , Epidermólisis Ampollosa Adquirida/tratamiento farmacológico , Humanos , Inmunoglobulinas Intravenosas , Inmunosupresores/uso terapéutico , Penfigoide Ampolloso/diagnóstico , Penfigoide Ampolloso/tratamiento farmacológico , Pénfigo , Rituximab/uso terapéutico , Enfermedades Cutáneas Vesiculoampollosas/tratamiento farmacológicoRESUMEN
BACKGROUND AND OBJECTIVES: Treatment of severe dermatological autoimmune diseases and toxic epidermal necrolysis (TEN) with high-dose intravenous immunoglobulin (IVIg) is a well-established procedure in dermatology. As treatment with IVIg is usually considered for rare clinical entities or severe cases, the use of immunoglobulin is not generally based on data from randomized controlled trials usually required for evidence-based medicine. Since the indications for the use of IVIg are rare, it is unlikely that such studies will be available in the foreseeable future. Because first-line use is limited by the high costs of IVIg, the first clinical guidelines on the use of IVIg in dermatological conditions were established in 2008 and renewed in 2011. METHODS: The European guidelines presented here were prepared by a panel of experts nominated by the EDF and EADV. The guidelines were developed to update the indications for treatment currently considered effective and to summarize the evidence for the use of IVIg in dermatological autoimmune diseases and TEN. RESULTS AND CONCLUSION: The current guidelines represent consensual expert opinions and definitions on the use of IVIg reflecting current published evidence and are intended to serve as a decision-making tool for the use of IVIg in dermatological diseases.
Asunto(s)
Enfermedades Autoinmunes/tratamiento farmacológico , Dermatología/normas , Inmunoglobulinas Intravenosas/administración & dosificación , Síndrome de Stevens-Johnson/tratamiento farmacológico , Enfermedades Autoinmunes/patología , Relación Dosis-Respuesta a Droga , Esquema de Medicación , Monitoreo de Drogas/normas , Medicina Basada en la Evidencia , Humanos , Inyecciones Intravenosas , Síndrome de Stevens-Johnson/patologíaRESUMEN
HINTERGRUND UND ZIELE: Die Behandlung schwerer dermatologischer Autoimmunerkrankungen und der toxischen epidermalen Nekrolyse (TEN) mit hochdosierten intravenösen Immunglobulinen (IVIg) ist ein bewährtes therapeutisches Verfahren in der Dermatologie. Da eine IVIg-Therapie in der Regel nur bei seltenen Erkrankungen oder bei schweren Fällen in Betracht gezogen wird, stützt sich die Anwendung von Immunglobulinen zumeist nicht auf Daten aus randomisierten kontrollierten Studien, wie sie in der evidenzbasierten Medizin erforderlich sind. Da Indikationen für die Anwendung von IVIg selten sind, ist es unwahrscheinlich, dass solche Studien in absehbarer Zeit durchgeführt werden. Wegen der hohen Kosten für IVIg im First-Line-Einsatz wurden die ersten klinischen Leitlinien für die Anwendung von IVIg bei dermatologischen Erkrankungen im Jahr 2008 herausgegeben und im Jahr 2011 überarbeitet. METHODEN: Diese europäischen Leitlinien wurden von einer Gruppe durch das EDF und die EADV benannter Experten erarbeitet. Die Leitlinien wurden erstellt, um die derzeit als wirksam erachteten Behandlungsindikationen zu aktualisieren und die für die Anwendung von IVIg bei dermatologischen Autoimmunerkrankungen und TEN vorliegenden Daten zusammenzufassen. ERGEBNISSE UND SCHLUSSFOLGERUNG: Die vorliegenden Leitlinien repräsentieren die einvernehmlichen Meinungen und Definitionen von Experten zur Anwendung von IVIg, die die aktuell publizierten Daten widerspiegeln, und sollen als Entscheidungshilfe für den Einsatz von IVIg bei dermatologischen Erkrankungen dienen.
RESUMEN
Pemphigus vulgaris (PV) is a potentially life-threatening autoimmune disease of the skin and mucous membranes. Its pathogenesis is based on IgG autoantibodies that target the desmosomal cadherins, desmoglein 3 (Dsg3) and desmoglein 1 (Dsg1) and induce intra-epidermal loss of adhesion. Although the PV pathogenesis is well-understood, therapeutic options are still limited to immunosuppressive drugs, particularly corticosteroids, which are associated with significant side effects. Dsg3-reactive T regulatory cells (Treg) have been previously identified in PV and healthy carriers of PV-associated HLA class II alleles. Ex vivo, Dsg3-specific Treg cells down-regulated the activation of pathogenic Dsg3-specific T-helper (Th) 2 cells. In this study, in a HLA-DRB1*04:02 transgenic mouse model of PV, peripheral Treg cells were modulated by the use of Treg-depleting or expanding monoclonal antibodies, respectively. Our findings show that, in vivo, although not statistically significant, Treg cells exert a clear down-regulatory effect on the Dsg3-driven T-cell response and, accordingly, the formation of Dsg3-specific IgG antibodies. These observations confirm the powerful immune regulatory functions of Treg cells and identify Treg cells as potential therapeutic modulators in PV.
Asunto(s)
Autoanticuerpos/química , Antígenos CD28/inmunología , Desmogleína 3/genética , Cadenas HLA-DRB1/inmunología , Pénfigo/inmunología , Linfocitos T Reguladores/metabolismo , Alelos , Animales , Anticuerpos Monoclonales/química , Antígenos CD28/genética , Proliferación Celular , Desmogleína 1/genética , Regulación hacia Abajo , Cadenas HLA-DRB1/genética , Humanos , Inmunoglobulina G/química , Inflamación , Ratones , Ratones Transgénicos , Pénfigo/genética , Proteínas Recombinantes/química , Linfocitos T Reguladores/citología , Células Th2/citología , Células Th2/metabolismoRESUMEN
Pemphigus vulgaris (PV) is considered as a model for an autoantibody-mediated organ-specific autoimmune disorder. IgG autoantibodies directed against the desmosomal cadherin desmoglein 3 (Dsg3), the major autoantigen in PV, cause loss of epidermal keratinocyte adhesion, resulting in blisters and erosions of the skin and mucous membranes. The association of human autoimmune diseases with distinct HLA alleles is a well-known phenomenon, such as the association with HLA-DRB1*04:02 in PV. However, direct evidence that HLA-DRB1*04:02-restricted autoreactive CD4(+) T cells recognizing immunodominant epitopes of Dsg3 initiate the production of Dsg3-reactive IgG autoantibodies is still missing. In this study, we show in a humanized HLA-DRB1*04:02-transgenic mouse model that HLA-DRB1*04:02-restricted T cell recognition of human Dsg3 epitopes leads to the induction of pathogenic IgG Abs that induce loss of epidermal adhesion, a hallmark in the immune pathogenesis of PV. Activation of Dsg3-reactive CD4(+) T cells by distinct human Dsg3 peptides that bind to HLA-DRß1*04:02 is tightly regulated by the HLA-DRB1*04:02 allele and leads, via CD40-CD40L-dependent T cell-B cell interaction, to the production of IgG Abs that recognize both N- and COOH-terminal epitopes of the human Dsg3 ectodomain. These findings demonstrate key cellular and humoral immune events in the autoimmune cascade of PV in a humanized HLA-transgenic mouse model. We show that CD4(+) T cells recognizing immunodominant Dsg3 epitopes in the context of the PV-associated HLA-DRB1*04:02 induce the secretion of Dsg3-specific IgG in vivo. Finally, these results identify Dsg3-reactive CD4(+) T cells as potential therapeutic targets in the future.
Asunto(s)
Autoanticuerpos/inmunología , Autoantígenos/inmunología , Desmogleína 3/inmunología , Cadenas HLA-DRB1/inmunología , Inmunoglobulina G/inmunología , Pénfigo/inmunología , Linfocitos T/inmunología , Linfocitos T/metabolismo , Secuencia de Aminoácidos , Animales , Especificidad de Anticuerpos/inmunología , Linfocitos B/inmunología , Linfocitos B/metabolismo , Comunicación Celular/inmunología , Células Dendríticas/inmunología , Células Dendríticas/metabolismo , Modelos Animales de Enfermedad , Epítopos/química , Epítopos/inmunología , Cadenas HLA-DRB1/genética , Humanos , Inmunización , Ratones , Ratones Transgénicos , Pénfigo/genética , Péptidos/química , Péptidos/inmunología , Unión Proteica , Piel/inmunología , Piel/metabolismo , Piel/patología , Subgrupos de Linfocitos T/inmunología , Subgrupos de Linfocitos T/metabolismoRESUMEN
Pemphigus refers to a group of potentially fatal blistering skin diseases that are often due to the deleterious effects of autoantibodies directed against desmosomal antigens. Although desmogleins have been mainly implicated as autoantigens in pemphigus, a steadily growing body of evidence suggests that other desmosomal proteins may be causally involved as well. Antibodies directed against desmocollin-3 have been shown to play a direct role in the pathogenesis of several types of pemphigus. Here we describe the case of a child with localized pemphigus foliaceus and immunoglobulin G (IgG) reactivity exclusively directed to desmocollins. The present report suggests that autoantibodies against nondesmoglein antigens may play a role in the pathogenesis of superficial pemphigus, in addition to pemphigus vulgaris, paraneoplastic pemphigus, and IgA pemphigus.
Asunto(s)
Autoanticuerpos/sangre , Autoantígenos/inmunología , Desmocolinas/inmunología , Inmunoglobulina G/sangre , Pénfigo/diagnóstico , Piel/patología , Niño , Ensayo de Inmunoadsorción Enzimática , Femenino , Técnica del Anticuerpo Fluorescente , Humanos , Pénfigo/inmunología , Pénfigo/patologíaRESUMEN
Low-affinity Fcγ receptors (FcγR) bridge innate and adaptive immune responses. In many autoimmune diseases, these receptors act as key mediators of the pathogenic effects of autoantibodies. Genes encoding FcγR exhibit frequent variations in sequence and gene copy number that influence their functional properties. FcγR variations also affect the susceptibility to systemic autoimmunity, e.g. systemic lupus erythematosus and rheumatoid arthritis. This raises the question whether FcγR variations are also associated with organ-specific autoimmunity, particularly autoantibody-mediated diseases, such as subepidermal autoimmune blistering diseases (AIBD). A multitude of evidence suggests a pathogenic role of neutrophil granulocyte interaction with autoantibodies via FcγR. In a two-stage study, we analyzed whether the FcγR genotype affects neutrophil function and mRNA expression, and consequently, bullous pemphigoid (BP) disease risk. We compared this to findings in pemphigus vulgaris/foliaceus (PV/PF), two Fc-independent AIBDs. Our results indicate that both allele and copy number variation of FcγR genes affect FcγR mRNA expression and reactive oxygen species (ROS) release by granulocytes. Susceptibility of BP was associated with FcγR genotypes that led to a decreased ROS release by neutrophils, indicating an unexpected protective role for these cells. BP and PV/PF differed substantially regarding the FcγR genotype association patterns, pointing towards different disease etiologies.
Asunto(s)
Enfermedades Autoinmunes/inmunología , Vesícula/inmunología , Variaciones en el Número de Copia de ADN/inmunología , Granulocitos/inmunología , Receptores de IgG/inmunología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Enfermedades Autoinmunes/genética , Vesícula/genética , Estudios de Casos y Controles , Niño , Preescolar , Variaciones en el Número de Copia de ADN/genética , Femenino , Proteínas Ligadas a GPI/genética , Proteínas Ligadas a GPI/inmunología , Expresión Génica/inmunología , Frecuencia de los Genes , Predisposición Genética a la Enfermedad/genética , Genotipo , Granulocitos/metabolismo , Humanos , Lactante , Recién Nacido , Masculino , Persona de Mediana Edad , Especies Reactivas de Oxígeno/inmunología , Especies Reactivas de Oxígeno/metabolismo , Receptores de IgG/genéticaRESUMEN
Mucous membrane pemphigoid encompasses a group of autoimmune bullous diseases with a similar phenotype characterized by subepithelial blisters, erosions, and scarring of mucous membranes, skin, or both. Although knowledge about autoimmune bullous disease is increasing, there is often a lack of clear definitions of disease, outcome measures, and therapeutic end points. With clearer definitions and outcome measures, it is possible to directly compare the results and data from various studies using meta-analyses. This consensus statement provides accurate and reproducible definitions for disease extent, activity, outcome measures, end points, and therapeutic response for mucous membrane pemphigoid and proposes a disease extent score, the Mucous Membrane Pemphigoid Disease Area Index.