Prospective study in bullous pemphigoid: association of high serum anti-BP180 IgG levels with increased mortality and reduced Karnofsky score

Anti-BP230 IgE autoantibodies in bullous pemphigoid intraindividually correlate with disease activity

BACKGROUND

Bullous pemphigoid (BP), the most common subepidermal autoimmune blistering disease, is classically defined by the presence of IgG autoantibodies directed against the hemidesmosomal proteins BP180 (type XVII collagen) and BP230 and the predominance of skin lesions. Several studies have addressed the role of anti-BP180 IgE in patients and experimental models, while data on anti-BP230 IgE are scarce.

OBJECTIVE

To assess anti-BP230 IgE level by ELISA in BP sera and to correlate it with disease severity and clinical characteristics.

METHODS

BP sera underwent anti-BP230 IgE ELISA and Western blotting against human BP230 fragments.

RESULTS

We demonstrate that 36/154 (23%) of BP sera were positive for anti-BP230 IgE. Anti-BP230 IgE levels had no correlation with clinical phenotype or disease activity per se. Interestingly, anti-BP230 IgE was significantly associated with disease activity within individuals during the course of the disease. Additionally, anti-BP230 IgE and total IgE levels showed a significant correlation. Notably, anti-BP230 IgG correlated interindividually with disease activity. By Western blotting, the C-terminal domain of BP230 fragments (C2; amino acids 2024-2349 and C3; amino acids 2326-2649), provided the best serological assay for anti-BP230 IgE detection.

CONCLUSION

As a complementary tool, IgE immunoblotting is recommended to obtain an optimal serological diagnosis, particularly in patients with severe disease without IgG reactivity by BP180- or BP230-specific ELISA. Although the detection of serum anti-BP230 IgE is not of major diagnostic significance, it may be relevant for therapeutic decisions, e.g., for anti-IgE-directed treatment, which has been successfully used in case series of BP.

Autoimmune blistering diseases: promising agents in clinical trials

INTRODUCTION

Treatment options for autoimmune bullous diseases (AIBD) are currently limited to corticosteroids and traditional immunomodulants and immunosuppressants that are associated with unfavorable adverse effect profiles. The most frequent AIBDs, i.e. bullous pemphigoid, pemphigus vulgaris, and mucous membrane pemphigoid, impose a high disease burden onto affected patients and can be detrimental due to infections, exsiccosis, and impaired food intake. Significant progress has been made in elucidating disease mechanisms and key mediators by in vivo and in vitro models, thus identifying a multifaceted range of possible drug targets. However, except for rituximab for pemphigus vulgaris, no new drugs have been approved for the treatment of AIBDs in the last decades.

AREAS COVERED

This review covers new drug developments and includes ongoing or completed phase 2 and 3 clinical trials. Studies were identified by querying the registries of ClinicalTrials.gov and Cochrane Library.

EXPERT OPINION

Promising results were shown for a variety of new agents including nomacopan, efgartigimod, omalizumab, dupilumab, as well as chimeric autoantibody receptor T cells. Clinical translation in the field of AIBDs is highly active, and we anticipate significant advances in the treatment landscape.

Evaluation of the immune colloidal gold technique for BP180-NC16A-specific antibodies in the quick diagnosis and monitoring of bullous pemphigoid

BACKGROUND

Bullous pemphigoid (BP) mostly involves elderly patients. The diagnosis of BP requires special immunological tests, which makes some patients unable to be diagnosed and treated timely.

OBJECTIVE

The accuracy and application value of immune colloidal gold technique (ICGT) in BP were evaluated. The colloidal gold was conjugated with recombinant BP180 NC16A protein and mouse IgG antibody. As the test and control lines, the mouse-anti-human IgG and goat-anti-mouse IgG, respectively, were blotted on the nitrocellulose membrane.

METHODS

414 serum samples of consecutive patients with suspected BP and 15 samples from healthy donors were recruited. The consistency between ICGT and ELISA, and between serum and plasma/whole blood were evaluated. Subgroup analyses were performed in terms of clinical characteristics. We also followed up 65 BP patients' strip results to explore the predictive value of ICGT.

RESULTS

Strong agreements between ICGT and ELISA(κ = 0.902) and between plasma/whole blood and serum samples (κ = 0.980) with good stability were observed. The ICGT achieved sensitivity of 93.9%, and specificity of 97.6%. In subgroup analysis, the sensitivity was significantly higher in older patients (96.3%), and with more typical lesions such as blisters (96.2%) and erosions (92.4%). In follow-up, we also found BP patients who kept ICGT-negative in remission state all got consecutive positive strips 1-3 weeks prior to mild new activity or flare.

CONCLUSION

ICGT shows high potential as a rapid and stable option for the diagnosis and monitoring of BP. Further investigations are needed to re-evaluate this technique in a prospective study with a multicenter design.

Differential expression of C5aR1 and C5aR2 in innate and adaptive immune cells located in early skin lesions of bullous pemphigoid patients

Bullous pemphigoid (BP), the by far most frequent autoimmune subepidermal blistering disorder (AIBD), is characterized by the deposition of autoantibodies against BP180 (type XVII collagen; Col17) and BP230 as well as complement components at the dermal-epidermal junction (DEJ). The mechanisms of complement activation in BP patients, including the generation of C5a and regulation of its two cognate C5aRs, i.e., C5aR1 and C5aR2, are incompletely understood. In this study, transcriptome analysis of perilesional and non-lesional skin biopsies of BP patients compared to site-, age-, and sex-matched controls showed an upregulated expression of C5AR1, C5AR2, CR1, and C3AR1 and other complement-associated genes in perilesional BP skin. Of note, increased expressions of C5AR2 and C3AR1 were also observed in non-lesional BP skin. Subsequently, double immunofluorescence (IF) staining revealed T cells and macrophages as the dominant cellular sources of C5aR1 in early lesions of BP patients, while C5aR2 mainly expressed on mast cells and eosinophils. In addition, systemic levels of various complement factors and associated molecules were measured in BP patients and controls. Significantly higher plasma levels of C3a, CD55, and mannose-binding lectin-pathway activity were found in BP patients compared to controls. Finally, the functional relevance of C5aR1 and C5aR2 in BP was explored by two in vitro assays. Specific inhibition of C5aR1, resulted in significantly reduced migration of human neutrophils toward the chemoattractant C5a, whereas stimulation of C5aR2 showed no effect. In contrast, the selective targeting of C5aR1 and/or C5aR2 had no effect on the release of reactive oxygen species (ROS) from Col17-anti-Col17 IgG immune complex-stimulated human leukocytes. Collectively, this study delineates a complex landscape of activated complement receptors, complement factors, and related molecules in early BP skin lesions. Our results corroborate findings in mouse models of pemphigoid diseases that the C5a/C5aR1 axis is pivotal for attracting inflammatory cells to the skin and substantiate our understanding of the C5a/C5aR1 axis in human BP. The broad expression of C5aRs on multiple cell types critical for BP pathogenesis call for clinical studies targeting this axis in BP and other complement-mediated AIBDs.

Survival and prognostic factors in bullous pemphigoid: A retrospective cohort study

Background

Bullous pemphigoid is the most common subepidermal autoimmune blistering disease. Till now, the reported prognostic factors in bullous pemphigoid vary considerably.

Aims

The purpose of this study was to determine the overall survival rate and prognostic factors in bullous pemphigoid.

Methods

We conducted a retrospective cohort study on newly diagnosed bullous pemphigoid patients between July 2001 and November 2019 in a referral unit for autoimmune blistering skin diseases in Romania.

Results

One hundred forty-eight patients were included in the study. The Kaplan-Meier overall survival rates at 1, 3, 5 and 10 years were respectively 74.2% (95% confidence interval, 67.5-81.6%), 53.4% (45.7-62.2%), 43.6% (35.9-53%) and 31.3% (23.5-41.7%). The median follow-up among survivors was 48 months (interquartile range: 11-150). Ninety (60.8%) patients died during the follow-up period; of them, 38 (42.2%) had active disease at the time of death. Advanced age, neurological diseases, valvular heart disease, malignancies, use of statins, skin infections and extensive cutaneous involvement were linked to poorer outcomes, while the use of topical corticosteroids was associated with increased overall survival.

Limitations

This study lacks a control cohort to validate the obtained results. It was conducted in a retrospective manner in a single centre. In addition, indirect immunofluorescence microscopy was not performed in all patients.

Conclusion

Beyond ageing and neurological comorbidities, the prognosis of bullous pemphigoid patients was significantly influenced by the presence of skin infections, valvular heart disease, use of statins and extensive cutaneous involvement. Topical corticosteroid treatment was associated with increased survival in these patients.

Mortality and prognostic factors in patients with bullous pemphigoid: a retrospective multicenter Italian study

INTRODUCTION

Bullous pemphigoid is the most common autoimmune bullous dermatosis. In recent years several studies have tried to identify the main factors of the disease related with an increased risk of death. The aim of this multicenter Italian study was to assess the risk score of death considering epidemiologic, clinical, immunological, and therapeutic factors in a cohort of patients affected by bullous pemphigoid and try to identify the cumulative survival up to 120 months.

METHODS

We retrospectively reviewed the medical records of patients with bullous pemphigoid who were diagnosed between 2005 and 2020 in the 12 Italian centers. Data collected included sex, age at the time of diagnosis, laboratory findings, severity of disease, time at death/censoring, treatment, and multimorbidity.

RESULTS

A total of 572 patients were included in the study. The crude mortality rate was of 20.6%, with an incidence mortality rate of 5.9x100 person/year. The mortality rate at 1,3,5 and 10 years was 3,2%, 18,2%, 27,4% and 51,9%, respectively. Multivariate model results showed that the risk of death was significantly higher in patients older than 78 years, in presence of multimorbidity, anti-BP180 autoantibodies>72 U/ml or anti-BP230>3 U/ml at diagnosis. The variables jointly included provided an accuracy (Harrel's Index) of 77% for predicting mortality.

CONCLUSION

This study represents the first nationwide Italian study to have retrospectively investigated the mortality rates and prognostic factors in patients with bullous pemphigoid. A novel finding emerged in our study is that a risk prediction rule based on simple risk factors (age, multimorbidity, steroid-sparing drugs, prednisone use and disease severity) jointly considered with two biomarkers routinely measured in clinical practice (anti-BP230 and anti-BP180 autoantibodies) provided about 80% accuracy for predicting mortality in large series of patients with this disease.

Serum autoantibody reactivity in bullous pemphigoid is associated with neuropsychiatric disorders and the use of antidiabetics and antipsychotics: a large prospective cohort study

BACKGROUND

Bullous pemphigoid (BP), the by far most frequent autoimmune blistering skin disease (AIBD), is immunopathologically characterized by autoantibodies against the two hemidesmosomal proteins BP180 (collagen type XVII) and BP230 (BPAG1 or dystonin). Several comorbidities and potentially disease-inducing medication have been described in BP, yet, a systematic analysis of these clinically relevant findings and autoantibody reactivities has not been performed.

OBJECTIVE

To determine associations of autoantibody reactivities with comorbidities and concomitant medication.

METHODS

In this prospective multicenter study, 499 patients diagnosed with BP in sixteen European referral centers were included. The relation between anti-BP180 NC16A and anti-BP230 IgG ELISA values at the time of diagnosis as well as comorbidities and concomitant medication collected by a standardized form were analyzed.

RESULTS

An association between higher serum anti-BP180 reactivity and neuropsychiatric but not atopic and metabolic disorders was observed as well as with the use of insulin or antipsychotics but not with dipeptidyl peptidase-4 (DPP4) inhibitors, inhibitors of platelet aggregation and L-thyroxine. The use of DPP4 inhibitors was associated with less anti-BP180 and anti-BP230 reactivity compared to BP patients without these drugs. This finding was even more pronounced when compared with diabetic BP patients without DPP4 inhibitors. Associations between anti-BP180 and anti-BP230 reactivities were also found in patients using insulin and antipsychotics, respectively, compared with patients without this medication, but not for the use of inhibitors of platelet aggregation, and L-thyroxine.

CONCLUSION

Taken together, these data imply a relation between autoantibody reactivities at the time of diagnosis and both neuropsychiatric comorbidities as well as distinct concomitant medication suggesting a link between the pathological immune mechanisms and clinical conditions that precede the clinically overt AIBD.

Emerging Biomarkers and Therapeutic Strategies for Refractory Bullous Pemphigoid

Bullous pemphigoid (BP) is the most common autoimmune subepidermal blistering disorder in the elderly. Systemic and topical use of glucocorticoids and immunosuppressants has been shown to be effective in most patients. However, refractory BP patients are challenged to clinicians with severe clinical symptoms, resistance to treatment, and high relapse rate. How to predict and assess the refractory and severity of bullous pemphigoid is the key issue in clinical practice, and the urgent need for precision medicine in refractory patients is driving the search for biomarkers and biologics. Recently, some biomarkers, such as the level of specific autoantibodies and released cytokines, have been proposed as the potential parameters to reflect the disease severity and predict the treatment response and relapse of refractory BP. Moreover, new biologics targeting pathogenic antibodies, complement, Th2 axis, eosinophils, and Th17 axis have shown potent efficacy on refractory BP. Here, we review the literature and give an overview of emerging biomarkers and therapeutic strategies for refractory bullous pemphigoid to improve the prognosis of the patient.

Bullous Autoimmune Dermatoses

BACKGROUND

Bullous autoimmune dermatoses are a clinically and immunopatho - logically heterogeneous group of diseases, characterized clinically by blisters or erosions of the skin and/or mucous membranes. In Germany, their prevalence is approximately 40 000 cases nationwide, and their incidence approximately 20 new cases per million people per year.

METHODS

This review is based on publications that were retrieved by a selective search of the literature focusing on the current German and European guidelines.

RESULTS

Recent years have seen the publication of guidelines, controlled prospective clinical trials, and multicenter diagnostic studies improving both diagnosis and therapy. Specific monovalent and multivariate serological test systems and pattern analysis of tissue-bound autoantibodies allow identification of the target antigens in 80-90% of patients. This enables the precise classification of disease entities, with implications for treatment selection and disease outcome. In 2019, the anti-CD20 antibody rituximab was approved by the European Medicines Agency for the treatment of moderate and severe pemphigus vulgaris, with an ensuing marked improvement in the care of the affected patients. To treat mild and moderate bullous pemphigoid, topical clobetasol proprionate is recommended, in severe disease, combined with systemic treatment, i.e. usually (a) prednisolone p.o. at an initial dose of 0.5mg/kg/d , (b) an immunomodulant, e.g. dapsone or doxycycline, or (c) prednisolone plus an immunomodulant.

CONCLUSION

The early recognition and precise diagnostic evaluation of bullous autoimmune dermatoses now enables improved, often interdisciplinary treatment, in accordance with the available guidelines. Current research projects are focused on new treatment approaches, an improved understanding of the underlying pathophysiology, and further refinements of diagnostic techniques.

Mortality of patients with bullous pemphigoid in Italy: a retrospective study of a monocentric experience

BACKGROUND

Mortality of bullous pemphigoid(BP) is a variable parameter,depending especially on the area where the study was conducted.The 1-year mortality rate and the identification of clinictherapeutic factors with potential prognostic value in patients with BP were evaluated in a cohort from a single referral center.

METHODS

We have reviewed medical records of patients with BP diagnosed at the Sant'Orsola-Malpighi Hospital in Bologna(Italy) between 2005 and 2019.Data collected included sex,age at diagnosis,laboratory findings,severity of disease,dosage of systemic treatments,age at death and comorbidities.Only patients who had at least 1 year of follow-up were included.

RESULTS

85 patients were included; the mortality rate was 7.1%.The mortality rate of patients treated with a moderate dosage of corticosteroids was no higher than that of patients treated with a low dosage.The log-rank test showed a statistically significant correlation between mortality and patients aged≥85,BP230 positive,and CCIS≥4.

CONCLUSIONS

Compared with similar studies,our results show a lower 1-year mortality rate.Advanced age at diagnosis and CCIS were confirmed as major independent factors associated with poor prognosis in BP.Administration of moderate dosage of oral corticosteroids seems to have an overall positive benefit-risk ratio,providing a good control of the disease and minimizing the risk of hospitalization,possible related complications and the mortality rate.

Subepithelial autoimmune bullous dermatoses disease activity assessment and therapy

Subepidermal (subepithelial) autoimmune blistering dermatoses are a group of rare skin disorders characterized by the disruption of the dermal-epidermal junction through the action of autoantibodies. The fourth article in this continuing medical education series presents the current validated disease activity scoring systems, serologic parameters, treatments, and clinical trials for bullous pemphigoid, mucous membrane pemphigoid, epidermolysis bullosa acquisita, bullous systemic lupus erythematosus, anti-p200 pemphigoid, linear IgA bullous dermatosis, and dermatitis herpetiformis.

Effect Evaluation of Combined Application of Magnetic Resonance Diffusion Tensor Imaging and Brain Function Imaging in Radiation Therapy of Brain Tumours Involving Motor Pathways

This study is an attempt to find a way for functional imaging information to be applied clinically in radiation therapy. The basal nucleus is a collective term for a group of neural nucleus in the central nervous system that connects the pontine, brainstem, and cerebral cortex, including the caudate nucleus, the bean-shaped nucleus, the screen-shaped nucleus, and the amygdala. It is difficult to find the exact position of these neural nuclei on the computed tomography (CT) image or the T1 or T2 sequence of magnetic resonance. However, the development of neurosurgery has partially confirmed that these functional nuclei are involved in advanced cognitive functions such as memory, emotion, and learning. Neurosurgery has tried to avoid damaging these nucleus groups during surgery to improve the quality of life of patients, and there is currently no clear strategy for this in radiotherapy. Because CT and magnetic resonance spin echo (SE) sequences are difficult to find the anatomical location of the nucleus, it is difficult to have any strategy to protect these functions in radiotherapy planning. This article uses diffusion tensor imaging (DTI) images and fiber bundle tracking to obtain a more accurate anatomical position of the nerve nucleus on the image, and provides some available strategies for radiotherapy to protect patients’ brain function. The conclusion of this paper is that the combined application of DTI and functional magnetic resonance imaging (fMRI) can better observe the relationship among tumours, functional areas and white matter fibers, and guide the designation of radiotherapy plans.

Bullous pemphigoid autoantibodies

<abstract> <p>Autoimmune blistering skin disorders are rare. According to direct immunofluorescence studies, three categories are described: pemphigus group, pemphigoid group and dermatitis herpetiformis. Among these diseases, bullous pemphigoid is the most common. Patients with typical bullous pemphigoid disease are usually elderly and have many comorbidities. Considering that topical and systemic corticosteroids are the first choice therapy, these patients also have increased morbidity and risk of death. The main characteristic of bullous pemphigoid as an acquired autoimmune blistering disease is the formation of autoantibodies against hemidesmosomal antigens BP180 and BP230. Although IgG autoantibodies predominate within the plasma and skin of BP patients, some features of the disease cannot be explained solely by IgG-mediated mechanisms. Epitope spreading phenomena, immunoglobulin class switch and the relevance of IgM and IgE autoantibodies are discussed in this article.</p> </abstract>

TH17/IL23 cytokine gene polymorphisms in bullous pemphigoid

Background

TH17/IL‐23 immune axis is considered to be involved in the pathogenesis of autoimmune and chronic inflammatory diseases. Bullous pemphigoid (BP) is the most frequent autoimmune blistering disease, characterized by the presence of autoantibodies against the components of the dermal‐epidermal junction. Animal studies and characterization of patient samples point toward a contribution of TH17 cells in BP pathogenesis. However, genetic polymorphisms in the genes of TH17/IL‐23 cytokines have not yet been well investigated in BP.

Methods

Detection of polymorphisms in IL‐17A (rs2275913 and rs3819025), IL‐17F (rs2397084 and rs763780), IL‐17RA (rs2229151), and IL‐23R (rs2201841, rs7530511, rs11209026, and rs10889677) genes were performed following the collection of blood samples and DNA extraction from BP patients and controls. Gene expression of IL‐23R was determined by quantitative RT‐PCR analysis.

Results

The prevalence of IL‐23R rs7530511 genotypes and alleles, as well as IL‐23R rs2201841 alleles, is significantly different between the BP patients and controls. While the minor C‐allele of IL‐23R rs7530511 is highly present in the patients, the G‐allele distribution of IL‐23R rs2201841 is significantly more prevalent in the control individuals compared to the BP patients. Genotypes and alleles of other SNPs in IL‐17A, IL‐17F, and IL‐17RA were similarly distributed in patients and controls.

Conclusions

No alteration was found in the gene expression between wild and polymorphic genotypes of IL‐23R (rs2201841 and rs7530511) variations, indicating they do not contribute to altering the levels of gene expression in blood. In summary, our data show that the alleles of two SNPs in IL‐23R rs2201841 and rs7530511 are associated with BP.

Clinical characteristics, mortality, and prognostic factors for bullous pemphigoid in a Thai population

Bullous pemphigoid is an uncommon, autoimmune, blistering disease. Clinical features, associated conditions, and outcomes differ according to country. We aimed to determine the mortality rate and clinical characteristics of Thai patients and to evaluate the risk factors associated with survival.A retrospective analysis was conducted on 119 patients, over a ten-year period, at Songklanagarind Hospital, the largest tertiary university hospital in Southern Thailand.The median age of onset was 82 years [interquartile range 72, 90], and 60 (50.4%) patients were men. The underlying diseases were hypertension (53.8%), neurological disease (42.8%), and diabetes mellitus (31.9%). Fifty-eight patients (48.7%) experienced pruritus, and 61.3% of patients had mild cutaneous lesions (less than 10% of the body surface area) on the day of diagnosis. Nine percent of patients presented with mucosal involvement. Complete blood counts showed anemia (32.8%), neutrophilia (30.3%), and eosinophilia (42.9%). The 1-, 3- and 5-year overall mortality rates were 28.1% [95% confidence interval (CI), 7.8-36.6], 55.7% (95% CI, 44.4-64.7) and 71.9% (95% CI 59.9-80.2), respectively. On multivariate analysis, high neutrophil/lymphocyte ratio [odds ratio (OR) 5.55, P < .001] and anemia (OR 2.93, P = .025) were found to be independently associated with mortality rate, whereas disease remission (OR 0.25, P = .003) was demonstrated to be a good prognostic factor.This is the first study to analyze the mortality rate of Bullous pemphigoid in Thailand. Mortality was associated with high neutrophil/lymphocyte ratio and anemia.

Association between TH2 Cytokine Gene Polymorphisms and Risk of Bullous Pemphigoid

Background: T-helper 2 (Th2)-associated cytokines are involved in the pathogenesis of bullous pemphigoid (BP), an autoimmune skin disease. Increased expression of Th2 cytokines such as interleukin-4 (IL-4), IL-5, IL-6, IL-10, and IL-13 have been observed in serum, skin biopsies and/or blister fluid. This study aimed to uncover a possible association between Th2 cytokine genetic variations and susceptibility to BP.Methods: In a cohort study, blood samples of BP patients and controls were obtained and variations in IL-4 (rs2243250 and rs2070874), IL-4R (rs1805010), IL-5 (rs2069812), IL-6 (rs1800795), IL-10 (rs1800896, rs1800871, and rs1800872), and IL-13 (rs1800925 and rs20541) were genotyped by PCR-RFLP assays. Furthermore, quantitative expression levels of IL-13 gene were evaluated by real-time RT-PCR analysis.Results: Among the studied variations, a significantly higher frequency of the C-allele was observed in IL-13 gene variation (rs1800925) in the healthy individuals than BP patients. This may indicate a protective effect of C-allele on predisposition to BP. Considering individuals carrying polymorphic genotypes compared to wild genotype, the minor G-allele of IL-4R rs1805010 and A-allele of IL-13 rs20541 had a promotive and protective effect, respectively, on predisposing to the development of BP. No significant difference in IL-13 mRNA expression was detected between BP patients and healthy individuals.Conclusions: Our results indicate that IL-13 rs1800925 variation may be a protective genetic marker for the development of BP. Given this preventive effect against BP, therapeutic strategies could potentially be developed interfering with the functions of IL-13 cytokine, which seems to be integral in the pathogenesis of eosinophilic inflammatory disorders, such as BP.

Total IgE, eosinophils, and interleukins 16, 17A, and 23 correlations in severe bullous pemphigoid and treatment implications

Bullous pemphigoid (BP) patients are predominantly above 70 years of age, with limited tolerance to the side effects of the immunosuppressive drugs. Advancements in our understanding of the pathophysiology of BP have led to the development of molecules which target specific pathways involved in induction and perpetuation of disease. Patients with BP Disease Area Index above 60 and less than 100 were split into two groups-one with high and the other with normal levels of IgE. The tested parameters included eosinophils' count, total IgE serum level, and interleukins (IL) 16, 17A, and 23 counts in the peripheral blood and skin bulla serum, before any therapeutic intervention. Thirty individuals fulfilled the criteria for enrollment. Patients with high IgE blood serum levels had significantly higher levels of IL17A and normal IL23 levels in blood and bulla serum. Patients with normal serum IgE levels had slightly higher IL23 levels in blood and bulla serum. The eosinophil count was positively related to IL17 blood serum level and negatively related to IL23. IL16 did not differ in the two groups. BP patients may represent a group of patients benefiting most substantially from the introduction of nonimmunosuppressive therapeutics into the treatment regimens for their disease. Clinical criteria and immune biomarkers are needed for making the best therapeutic choice.

Anti-BP180 autoantibody levels at diagnosis correlate with 1-year mortality rates in patients with bullous pemphigoid

BACKGROUND

Bullous pemphigoid (BP) is the most frequent autoimmune blistering disease mainly affecting elderly patients. Among several published risk factors, a recent post hoc analysis linked anti-BP180 autoantibodies (AABs) to fatal outcomes in BP. To date, this finding has not been confirmed independently.

OBJECTIVE

To investigate the potential of anti-BP180-AAB levels as a marker of prognosis and to identify a cut-off level indicative of an increased risk for early death. Secondly, to characterize parameters associated with mortality.

METHODS

Retrospective, single-centre study of BP patients diagnosed between 2001 and 2012. Analyses included epidemiological and patient- and disease-specific characteristics as well as immunological parameters at diagnosis and during follow-up. Standardized mortality ratios as well as uni- and multivariate regression analyses were calculated.

RESULTS

One hundred patients (56 women, 44 men) with a median age of 81 years (interquartile range 74-86) were followed up for a median of 775 days (interquartile range 162-1617). One-year mortality rates were 25.0% implying a 2.4-fold increased risk of death compared with the general population. High anti-BP180 autoantibody levels at diagnosis (CI₉₅ 1.30-2.89; P = 0.001), dementia (CI₉₅ 1.13-6.72; P =0.03), length of hospitalization (CI₉₅ 1.16-2.41; P = 0.01) and age (CI₉₅ 1.23-4.19; P = 0.009) correlated significantly with 1-year mortality. BP180-AAB concentrations of ≥61 U/mL characterized a subgroup of patients with a particular higher risk for early death compared with the general population (CI₉₅ 1.81-3.81; P < 0.0001).

CONCLUSION

In bullous pemphigoid, serum concentrations of BP180 autoantibodies at diagnosis could help to identify patients at risk for death within the first year after diagnosis (cut-off value 61 U/mL).

Advances in the diagnosis of autoimmune bullous dermatoses

Autoimmune bullous dermatoses are defined by autoantibodies directed against adhesion proteins in the epidermis or basement membrane zone, resulting in blister formation on the skin and mucosa. Diagnosis depends on lesional biopsy for histopathology and perilesional biopsy for direct immunofluorescence. Additional diagnostic methods include indirect immunofluorescence, enzyme-linked immunosorbent assay, and immunoblot (Western blot), which may be selected in specific clinical scenarios due to improved sensitivity and/or specificity. This contribution reviews the available evidence supporting the use of each method to provide a practical reference for clinicians when diagnosing autoimmune bullous disorders. Techniques and cost are reviewed, and newer diagnostic techniques with potential for clinical application are.

Circulating bullous pemphigoid autoantibodies in the setting of negative direct immunofluorescence findings for bullous pemphigoid: A single-center retrospective review

BACKGROUND

Bullous pemphigoid (BP) autoantibody levels are generally elevated in patients with BP but can be present nonspecifically in patients without BP.

OBJECTIVE

To analyze the clinical findings of patients with elevated BP180 or BP230 autoantibody levels and negative direct immunofluorescence (DIF) study findings.

METHODS

We retrospectively reviewed records of patients seen at our institution during January 1, 2005-December 31, 2015, who were positive for BP180 or BP230 autoantibodies and had a negative DIF study finding. These patients' demographic characteristics and BP180 and BP230 levels were compared with those of a BP control group who were positive for BP180 or BP230 autoantibodies and had positive DIF study findings.

RESULTS

We identified 208 patients with BP autoantibodies but without positive DIF study findings. These patients' mean age and enzyme-linked immunosorbent assay values were significantly lower than those of the control group. Dermatitis was the most common final clinical diagnosis. Of the 208 patients, 41 (19.7%) had at least 2 years' follow-up. Four patients had positive DIF results upon repeating the test and ultimately received pemphigoid diagnoses.

LIMITATIONS

Retrospective design with limited follow-up.

CONCLUSION

Patients might harbor serum BP autoantibodies in the context of a wide range of dermatoses. Low positive BP180 and BP230 autoantibody levels should not be overinterpreted as evidence for BP in the setting of a negative DIF.

New Insights Into the Pathogenesis of Bullous Pemphigoid: 2019 Update

There are several lines of evidence indicating that the physiopathological bases of bullous pemphigoid (BP), the most common subepidermal autoimmune bullous disease, are hallmarked by the production of autoantibodies directed against the hemidesmosomal anchoring proteins BP180 and BP230. In contrast to the robustness of the latter assumption, the multifaceted complexity of upstream and downstream mechanisms implied in the pathogenesis of BP remains an area of intense speculation. So far, an imbalance between T regulatory cells and autoreactive T helper (Th) cells has been regarded as the main pathogenic factor triggering the autoimmune response in BP patients. However, the contributory role of signaling pathways fostering the B cell stimulation, such as Toll-like receptor activation, as well as that of ancillary inflammatory mechanisms responsible for blister formation, such as Th17 axis stimulation and the activation of the coagulation cascade, are still a matter of debate. In the same way, the pathomechanisms implied in the loss of dermal-epidermal adhesion secondary to autoantibodies binding are not fully understood. Herein, we review in detail the current concepts and controversies on the complex pathogenesis of BP, shedding light on the most recent theories emerging from the literature.

Normal human skin is superior to monkey oesophagus substrate for detection of circulating BP180-NC16A-specific IgG antibodies in bullous pemphigoid

BACKGROUND

Bullous pemphigoid (BP) is the most common autoimmune subepidermal blistering skin disease. Two antigens have been identified as targets of circulating autoantibodies (autoAbs) - BP180 and BP230 - with BP180 being a critical transmembrane adhesion protein of basal keratinocytes of the epidermis. The noncollagenous domain 16A (NC16A) of BP180 is the immunodominant epitope in patients with BP, and anti-BP180-NC16A IgG antibodies (Abs) correlate to disease activity. Routine serological testing and follow-up of BP relies on indirect immunofluorescence (IIF) of serum Abs, commonly performed on monkey oesophagus (ME), and/or enzyme-linked immunosorbent assay (ELISA) testing on recombinantly produced fragments of BP180 and BP230 (BP180-NC16A, BP230-C/N).

OBJECTIVES

To determine if NC16A epitopes are well represented on ME substrate.

METHODS

Sera from different BP cohorts were tested by IIF on ME and normal human skin (NHS). To confirm findings, affinity-purified anti-BP180-NC16A/BP230 polyclonal Abs and recombinant anti-BP180-NC16A/BP230 monoclonal antibodies (mAbs) were used.

RESULTS

For sensitive detection of BP180-NC16A-specific IgG Abs, sections of NHS are superior to the widely used ME. Confirmation comes from polyclonal affinity-purified anti-BP180-NC16A/BP230 Abs, and by mAbs cloned from a patient with active BP.

CONCLUSIONS

Use of NHS is preferable over ME in routine IIF testing for BP. These results are of clinical relevance because anti-BP180-NC16A IgG titres are correlated to disease activity and detecting them reliably is important for screening, diagnosis and follow-up of patients with BP.

Proinflammatory Cytokine Gene Polymorphisms in Bullous Pemphigoid

Bullous pemphigoid (BP) is a rare autoimmune skin blistering disease, characterized by the presence of autoantibodies against hemidesmosomal autoantigens. Cytokine expression is altered in BP patients, and several of these differently expressed cytokines, including IL-1α, IL-1β, IL-8, and TNF-α, contribute to disease pathogenesis. Since genetic polymorphisms in the genes of these cytokines might be implicated in susceptibility to BP disease, we aimed at testing this implication in susceptibility to BP in an Iranian cohort. Blood samples were collected from the subjects and genomic DNA was extracted. To detect the single nucleotide polymorphisms (SNPs), IL-1α (rs1800587), IL-1β (rs1143627, rs16944, rs1143634), IL-8 (rs4073), and TNF-α (rs1799964, rs1800630, rs1799724, and rs361525) genes were genotyped in BP patients and healthy controls as well as IL-8 (rs4073) in pemphigus vulgaris (PV) patients. Quantitative gene expression was evaluated by RT-PCR analysis. A significant difference was observed in the distribution of genotypes or alleles of IL-8 SNP between the BP patients and controls. The A-allele of IL-8 SNP is significantly more prevalent in the control individuals compared to the BP patient. To further validate this observation, we included PV patients as an additional control. Again, the A-allele of IL-8 SNP is significantly more prevalent in the PV compared to the BP patients. While we observed a trend toward significant differences regarding alleles of TNF-α rs1799724 as well as alleles of TNF-α rs1799964, this difference was, however, not evident after correction for multiple analysis. There was no significant difference in all other studied SNPs. In contrast to IL-1α, IL-1β, and TNF-α, IL-8 gene expression levels were significantly higher in the patients than that of controls. The minor allele in IL-8 SNP might play a protective role in susceptibility to BP in Iranian patients. Although higher expression levels of IL-8 gene was found in the patients compared with healthy controls, these levels, however, suggest no association with the examined polymorphism. Moreover, further investigation revealed an elevation in gene expression between wild and polymorphic genotypes of IL-1α rs1800587 and TNF-α rs361525 in the patient group and these SNPs are therefore associated with altering the levels of gene expression.

Bullous pemphigoid

Bullous pemphigoid is the most frequent autoimmune bullous disease and mainly affects elderly individuals. Increase in incidence rates in the past decades has been attributed to population aging, drug-induced cases and improvement in the diagnosis of the nonbullous presentations of the disease. A dysregulated T cell immune response and synthesis of IgG and IgE autoantibodies against hemidesmosomal proteins (BP180 and BP230) lead to neutrophil chemotaxis and degradation of the basement membrane zone. Bullous pemphigoid classically manifests with tense blisters over urticarial plaques on the trunk and extremities accompanied by intense pruritus. Mucosal involvement is rarely reported. Diagnosis relies on (1) the histopathological evaluation demonstrating eosinophilic spongiosis or a subepidermal detachment with eosinophils; (2) the detection of IgG and/or C3 deposition at the basement membrane zone using direct or indirect immunofluorescence assays; and (3) quantification of circulating autoantibodies against BP180 and/or BP230 using ELISA. Bullous pemphigoid is often associated with multiple comorbidities in elderly individuals, especially neurological disorders and increased thrombotic risk, reaching a 1-year mortality rate of 23%. Treatment has to be tailored according to the patient's clinical conditions and disease severity. High potency topical steroids and systemic steroids are the current mainstay of therapy. Recent randomized controlled studies have demonstrated the benefit and safety of adjuvant treatment with doxycycline, dapsone and immunosuppressants aiming a reduction in the cumulative steroid dose and mortality.