Upadacitinib for the management of bullous pemphigoid coexisting with psoriasis vulgaris: a case report and literature review

Both bullous pemphigoid (BP) and psoriasis are common immune-related dermatological conditions in clinical practice, but the co-occurrence of these two diseases is rare. Currently, there is no consensus on the long-term safe and effective treatment for patients with both BP and psoriasis. JAK inhibitors are emerging as targeted therapeutic drugs that act by inhibiting Janus kinase activity, regulating the JAK/STAT pathway, blocking the transduction pathway of key proinflammatory cytokines, and influencing T-cell differentiation. These cytokines upstream of the JAK/STAT pathway play a pivotal role in the pathogenesis of numerous inflammatory and autoimmune disorders. Upadacitinib, a second-generation JAK inhibitor with high selectivity, demonstrates promising potential.This case report aims to provide a description of the successful treatment of bullous pemphigoid (BP) and psoriasis vulgaris by using upadacitinib, highlighting significant clinical outcomes. Additionally, we aim to analyze the underlying mechanism of upadacitinib in treating these two comorbidities by reviewing relevant literature from both domestic and international sources. Based on our clinical observations, upadacitinib appears to be a promising and well-tolerated therapeutic option for patients with concurrent BP and psoriasis, offering valuable insights for developing appropriate treatment strategies in clinical practice.

Understanding patient perspectives on vaccine decision making in adults with autoimmune bullous diseases: a qualitative study

Patients with autoimmune bullous diseases are at an increased risk of infection, both from the underlying skin disease and from immunosuppressive treatments. Limited information is available on vaccine beliefs and behaviors in dermatology patients and adults with autoimmune bullous diseases in particular. To understand vaccine decision making, identify perceived risks and benefits of vaccinations, and discuss individual experiences in patients with autoimmune bullous diseases in the United States. A qualitative study was performed utilizing semi-structured interviews, and analysis was conducted on NVivo. Patterns were identified in the coded data, and representative quotations were recorded for each major theme. Interviews were conducted between February 15, 2022 and September 15, 2022. Twenty patients with a diagnosis of bullous pemphigoid, mucous membrane pemphigoid, pemphigus vulgaris, or pemphigus foliaceous were interviewed. Of the 20 participants, 14 (70%) were female, with a mean (SD, range) age of 64.8 (13.2, 34-83) years. Key themes that emerged from qualitative analysis of the interviews included patient concerns regarding their increased susceptibility to infection, potential exacerbation of skin disease following vaccination, and the effect of immunosuppressive medications on humoral response to vaccines. Lack of appointment availability, difficulty accessing vaccines, and cost were commonly identified barriers to vaccination. These findings provide valuable knowledge for dermatologists in regard to providing counseling specific to patient concerns and to improve communication surrounding vaccination in the dermatology setting.

Presence of immunoglobulin E-expressing antibody-secreting cells in the dermis close to bullous pemphigoid lesions

Antibody-secreting cells (ASCs) produce immunoglobulin (Ig) G and IgE autoantibodies in secondary lymphoid organs. Evidence also suggests their existence in the skin in various chronic inflammatory conditions, and in association with CXCL12 and CXCL13, they regulate the recruitment/survival of ASCs and germinal center formation to generate ASCs, respectively. However, the presence of IgG and IgE in bullous pemphigoid (BP) lesions needs to be addressed. Here, we aimed to analyse BP skin for the presence of IgG and IgE and the factors contributing to their generation, recruitment, and persistence. Skin samples from 30 patients with BP were stained to identify ASCs and the immunoglobulin type they expressed. The presence of tertiary lymphoid organ (TLO) elements, which generate ASCs in non-lymphoid tissues, and the chemokines CXCL12 and CXCL13, which regulate the migration/persistence of ASCs in lymphoid tissues and formation of TLOs, respectively, were evaluated in BP skin. BP skin harboured ASCs expressing the two types of antibodies IgG and IgE. ASCs were found in high-grade cellular aggregates containing TLO elements: T cells, B cells, CXCL12+ cells, CXCL13+ cells and high endothelial venules. IgG+ ASCs were detected among these aggregates, whereas IgE+ ASCs were dispersed throughout the dermis. CXCL12+ fibroblast-like cells were located close to ASCs. The inflammatory microenvironment of BP lesions may contribute to the antibody load characteristic of the skin of patients with BP by providing a site for the presence of ASCs. CXCL13 and CXCL12 expression may contribute to the generation and recruitment/survival of ASCs, respectively.

Laminin β4 is a constituent of the cutaneous basement membrane zone and additional autoantigen of anti-p200 pemphigoid

BACKGROUND

Anti-p200 pemphigoid is a subepidermal autoimmune blistering disease (AIBD) characterized by autoantibodies against a 200 kDa protein. Laminin γ1 has been described as target antigen in 70% to 90% of patients. No diagnostic assay is widely available for anti-p200 pemphigoid, which might be due to the unclear pathogenic relevance of anti-laminin γ1 autoantibodies.

OBJECTIVE

To identify a target antigen with higher clinical and diagnostic relevance.

METHODS

Immunoprecipitation, mass spectrometry, and immunoblotting were employed for analysis of skin extracts and sera of patients with anti-p200 pemphigoid (n = 60), other AIBD (n = 33), and healthy blood donors (n = 29). To localize the new antigen in skin, cultured keratinocytes and fibroblasts, quantitative real-time polymerase chain reaction and immunofluorescence microscopy were performed.

RESULTS

Laminin β4 was identified as target antigen of anti-p200 pemphigoid in all analyzed patients. It was located at the level of the basement membrane zone of the skin with predominant expression in keratinocytes.

LIMITATIONS

A higher number of sera needs to be tested to verify that laminin β4 is the diagnostically relevant antigen of anti-p200 pemphigoid.

CONCLUSION

The identification of laminin β4 as an additional target antigen in anti-p200 pemphigoid will allow its differentiation from other AIBD and as such, improve the management of these rare disorders.

Anti-α6β4 integrin autoantibodies inhibit the binding of laminins to α6β4 integrin in patients with pemphigoid and affect the gastrointestinal tract

BACKGROUND

Anti-α6β4 integrin autoantibodies can be observed in some patients with mucous membrane pemphigoid. We have previously identified anti-α6β4 integrin extracellular domain autoantibodies together with anti-BP180 NC16A antibodies in a patient with DPP-4 inhibitor-induced bullous pemphigoid. However, the significance and impact of anti-α6β4 integrin antibodies are unknown.

OBJECTIVES

To characterize anti-α6β4 integrin extracellular domain autoantibodies in pemphigoid patients, to determine whether these antibodies inhibit laminin-α6β4 integrin binding and to observe their systemic effects.

METHODS

Anti-α6β4 integrin autoantibodies were analysed by staining cells expressing the extracellular region of α6β4 integrin with sera from 20 patients with pemphigoid. The anti-α6β4 integrin autoantibodies were characterized using different transfectants. The binding of laminins to α6β4 integrin was studied using cells expressing the activated conformation of α6β4 integrin and the inhibitory effect of the autoantibodies on the binding of laminins to α6β4 integrin was tested. Trends in antibody titres and clinical symptoms were quantified and analysed.

RESULTS

IgG autoantibodies against the extracellular domain of anti-α6β4 integrin were found in some patients with pemphigoid. Laminin binding to α6β4 integrin was observed in the active conformation of α6β4 integrin, and serum from a patient with a high titre of anti-α6β4 integrin antibodies inhibited the binding of both laminin-511 and laminin-332 to α6β4 integrin. α6β4 integrin is expressed on the basement membrane of both skin and small intestine, and exfoliation was observed in the patient's epidermis and small intestinal epithelium. A reduction in the titre of the anti-α6β4 integrin antibody was associated with improvement in both skin and gastrointestinal symptoms.

CONCLUSIONS

This study demonstrated the presence of anti-α6β4 integrin extracellular domain-specific autoantibodies in some patients with pemphigoid. In addition, these autoantibodies showed inhibitory activity on α6β4 integrin-laminin binding. Anti-α6β4 integrin antibodies can affect the gastrointestinal tract as well as the skin and oral mucosa.

Expression of Serum Anti-BP180/230 Antibodies in Bullous Pemphigoid Patients Combined with Nervous System Diseases and Relevant Factor Analysis

OBJECTIVE

To explore the anti-BP230/180 and anti-BP180 antibodies in patients with bullous pemphigoid (BP) combined with neurological diseases, and to analyse the relevant factors.

STUDY DESIGN

Analytical study. Place and Duration of the Study: Neurology Department, Cangzhou People's Hospital, Cangzhou, from April 2019 to June 2022.

METHODOLOGY

Eighty BP patients were chosen based on associated neurological diseases, they were split into single (n=42) and combined groups (n=38). Expression of anti-BP180/230 antibodies was compared between the two groups. Associations with neurological diseases were analysed and the factors affecting the expression of anti-BP180/230 antibodies were explored.

RESULTS

Out of 80 patients, 61 were positive for anti-BP180 antibodies and 58 were positive for anti-BP230 antibodies. The proportion of patients with positive anti-BP230/180 antibodies in the single group was considerably lower than in the combined group (p<0.05). Presence of both nervous system diseases and BP was found to be associated with the presence of anti-BP230/180 antibodies (p<0.001). Univariate analysis showed statistically significant association with age (<70 years, total IgE (>100 IU/ml), and EOS count >0.5 x 109/L (p<0.05). Logistic analysis demonstrated that age, total IgE and EOS count were independent risk factors affecting the expression of anti-BP180 and anti-BP23 antibodies (p<0.05).

CONCLUSION

Serum anti-BP230/180 antibodies expression is abnormally high in BP patients having nervous system diseases. Combined nervous system diseases, age, total IgE and EOS count are independent risk factors affecting expression of anti-BP180/230 antibodies.

KEY WORDS

Anti-BP180 antibody, Anti-BP230 antibody, Bullous pemphigoid, Nervous system diseases.

Direct Immunofluorescence Findings and Factors Affecting Conjunctival Biopsy Positivity in Ocular Mucous Membrane Pemphigoid

PURPOSE

The aim of this study was to describe the direct immunofluorescence (DIF) findings and factors affecting conjunctival biopsy positivity in patients clinically diagnosed with ocular mucous membrane pemphigoid (OMMP).

METHODS

This retrospective observational case series included patients with clinical OMMP who underwent conjunctival biopsy for DIF in at least 1 eye between 2018 and 2021 in an institutional setting. The primary outcome measures were association of age and chronic ocular complications with biopsy positivity.

RESULTS

Of 61 patients, DIF positivity was seen in 33 (54.1%) clinically suspected cases of OMMP. Of 39 patients who underwent bilateral biopsy, 23 (59%) were positive, of which 12 (52%) were positive in both eyes while 11 (48%) were positive in 1 eye. Of 22 patients who underwent unilateral biopsy, 10 (45%) were positive. Of the 100 biopsied eyes, 45 (45%) were DIF positive. Among the immunoreactants studied, linear deposition of C3 was seen in all 45 positive eyes (100%). Increasing age was significantly associated with higher likelihood of biopsy negativity ( P = 0.032), whereas a greater Sotozono chronic ocular complication score, indicative of disease severity, was associated with low likelihood of biopsy positivity ( P = 0.0042) and lower overall expression of immunoreactants on DIF ( P = 0.0007).

CONCLUSIONS

Older patients and patients with more severe ocular surface disease sequelae are likely to have negative DIF results. To optimize the chances of confirming the diagnosis of OMMP by DIF, both eyes should be biopsied early in the disease course. If 1 eye is being biopsied, the less affected eye must be chosen.

Clinical Features of Paediatric Inflammatory Epidermolysis Bullosa Acquisita: A Case Series Study

Epidermolysis bullosa acquisita (EBA) rarely develops in childhood. This study retrospectively recruited paediatric patients with EBA (age ≤ 16 years), diagnosed by clinical and histopathological features and results of immunofluorescence, immunoblotting and enzyme-linked immunosorbent assay (ELISA), and reviews their clinical manifestations, histopathology, immunological features, and responses to various treatments. All 7 included patients presented with inflammatory EBA. Among them, 3 had a bullous pemphigoid-like phenotype. Pathologically, in addition to dermal-epidermal blistering, in all patients, the distribution of neutrophils was superficial perivascular or interstitial, or in the dermal papilla. Mixed neutrophils and eosinophils were detected in 2 of the 3 patients with bullous pemphigoid-like phenotypes. In addition to treatment with glucocorticoids, dapsone was administered in 4 patients, while thalidomide and sulfasalazine were administered in 1 patient. All patients responded to the these therapies. Relapse was mainly due to reduction and cessation of glucocorticoids. In conclusion, EBA in childhood may be unique, and thus distinct from its adult counterpart. Specific treatment and follow-up protocols are required for therapy of this rare autoimmune skin disease in children.

Study of cytokine-induced immunity in bullous pemphigoid: recent developments

Bullous pemphigoid (BP) is an organ-specific disease. Its pathogenesis has not been clearly studied yet; However, studies in recent years have shown that its pathogenesis is related to T helper cells. The pathogenesis of BP is mainly related to Th2 and Th17-related cytokines. IL-4, IL-5 and IL-13 cause eosinophil recruitment, promote antibody production, trigger pruritus and promote blister formation and other symptoms. IL-17 and IL-23 promote the production of matrix metalloproteinase-9 (MMP-9) by related cells, which causes dermo-epidermal junction (DEJ) separation to form bullae and blisters, and can persist in BP inflammation. The serum concentrations of IL-17 and IL-23 are related to the prognosis of BP. In this paper, we focus on the role of related cytokines in the pathogenesis of bullous pemphigoid and the relationship between the related cytokine populations secreted by three major T helper cells-helper T lymphocytes 1 (Th1), Th2, and Th17. A better understanding of the biological and immunological functions of cytokines associated with BP patients will provide opportunities for therapeutic targets in BP.

Approach to red, scaly eruptions in the older patient

BACKGROUND

Older patients with a red scaly eruption often present first to a primary care practitioner. A thorough clinical assessment can help delineate between common causes and assist the clinician with the next steps in management.

OBJECTIVE

This article discusses the assessment of acute- to subacute-onset erythematous and scaly plaques that are present on multiple body sites in a patient aged >65 years.

DISCUSSION

The differential diagnosis of a red, scaly rash in an older patient includes atopic dermatitis, psoriasis, generalised drug eruption, tinea, scabies and non-bullous pemphigoid. Less common causes include subacute cutaneous lupus and mycosis fungoides. If the diagnosis is unclear after clinical assessment, a skin biopsy sent for histopathology, and/or direct immunofluorescence can be very useful. Management requires consideration of physical impairments, carer availability and cost.

Bullous pemphigoid anti-BP180-NC16A autoantibody reactivity in healthy individuals is associated with marked hypovitaminosis D and Th2-like cytokine predominance

Autoimmune bullous disease autoantibodies, particularly including bullous pemphigoid (BP)-related anti-BP180-NC16A IgG, have been reported in a small subset of healthy individuals, but information about associated factors is lacking. We hypothesized that an abnormal status of immunomodulatory vitamin D could play a role in anti-BP180-NC16A autoantibody reactivity in healthy persons. In addition, we aimed to evaluate the cytokine profile associated with these autoantibodies. Plasma samples from 34 anti-BP180-NC16A IgG-reactive and 85 anti-BP180-NC16A IgG-negative healthy blood donors were tested for levels of 25-hydroxyvitamin D [25(OH)D] and a wide range of cytokines (IL-2, IL-4, IL-5, IL-6, IL-9, IL-10, IL-13, IL-17A, IL-17F, IL-21, IL-22, IFN-γ, and TNF-α). We observed that anti-BP180-NC16A IgG-reactive healthy subjects had significantly lower plasma 25(OH)D levels and about a two-fold higher rate of vitamin D deficiency (< 20 ng/ml) compared to anti-BP180-NC16A IgG-negative healthy persons. In addition, anti-BP180-NC16A IgG-positive samples were characterized by significantly higher levels of IL-2, IL-5, IL-9, IL-10, and IL-13 which were, however, not significantly associated with the vitamin D levels. Our results indicate that healthy individuals with BP autoantibody reactivity share similarities with BP patients regarding the vitamin D status and cytokine profile (i.e., marked hypovitaminosis D and Th2 predominance), which may have pathophysiologic implications.

Advancing Treatment in Bullous Pemphigoid: A Comprehensive Review of Novel Therapeutic Targets and Approaches

Bullous pemphigoid is one of the most common autoimmune bullous diseases occurring primarily in the elderly. Pathogenic autoantibodies against BP180 and BP230 at the dermal-epidermal junction cause subepidermal blisters, erosions, and intense pruritus, all of which adversely affect the patients' quality of life and may increase their morbidity and mortality. Current systemic treatment options for bullous pemphigoid are limited to corticosteroids and immunosuppressants, which can have substantial side effects on these vulnerable patients that even exceed their therapeutic benefits. Therefore, more precisely, targeting therapies to the pathogenic cells and molecules in bullous pemphigoid is an urgent issue. In this review, we describe the pathophysiology of bullous pemphigoid, focusing on autoantibodies, complements, eosinophils, neutrophils, proteases, and the T helper 2 and 17 axes since they are crucial in promoting proinflammatory environments. We also highlight the emerging therapeutic targets for bullous pemphigoid and their latest discoveries in clinical trials or experimental studies. Further well-designed studies are required to establish the efficacy and safety of these prospective therapeutic options.

The gut microbiome in bullous pemphigoid: implications of the gut-skin axis for disease susceptibility

Bullous pemphigoid (BP) is an autoimmune blistering disease that primarily affects the elderly. An altered skin microbiota in BP was recently revealed. Accumulating evidence points toward a link between the gut microbiota and skin diseases; however, the gut microbiota composition of BP patients remains largely underexplored, with only one pilot study to date, with a very limited sample size and no functional profiling of gut microbiota. To thoroughly investigate the composition and function of the gut microbiota in BP patients, and explore possible links between skin conditions and gut microbiota, we here investigated the gut microbiota of 66 patients (81.8% firstly diagnosed) suffering from BP and 66 age-, sex-, and study center-matched controls (CL) with non-inflammatory skin diseases (132 total participants), using 16S rRNA gene and shotgun sequencing data. Decreased alpha-diversity and an overall altered gut microbial community is observed in BP patients. Similar trends are observed in subclassifications of BP patients, including first diagnoses and relapsed cases. Furthermore, we observe a set of BP disease-associated gut microbial features, including reduced Faecalibacterium prausnitzii and greater abundance of pathways related to gamma-aminobutyric acid (GABA) metabolism in BP patients. Interestingly, F. prausnitzii is a well-known microbiomarker of inflammatory diseases, which has been reported to be reduced in the gut microbiome of atopic dermatitis and psoriasis patients. Moreover, GABA plays multiple roles in maintaining skin health, including the inhibition of itching by acting as a neurotransmitter, attenuating skin lesions by balancing Th1 and Th2 levels, and maintaining skin elasticity by increasing the expression of type I collagen. These findings thus suggest that gut microbiota alterations present in BP may play a role in the disease, and certain key microbes and functions may contribute to the link between gut dysbiosis and BP disease activity. Further studies to investigate the underlying mechanisms of the gut-skin interaction are thus clearly warranted, which could aid in the development of potential therapeutic interventions.

Alterations in Inflammation Markers Due to Disease Activation in Autoimmune Bullous Diseases

BACKGROUND

In the pathogenesis of autoimmune bullous diseases, there is an underlying autoinflammation against epidermal/subepidermal structures caused by many inflammatory cells. Aim / Objectives: In this study, we aimed to determine the alterations in inflammatory markers regarding disease activity in autoimmune bullous diseases and to discuss their contribution to the pathogenesis.

METHODS

A total of 191 patients with pemphigus vulgaris (PV) and 46 patients with bullous pemphigoid (BP) who were admitted to the outpatient clinic at the Department of Dermatology were included. The mean platelet volume (MPV) values, thrombocyte, eosinophil, and basophil counts, erythrocyte sedimentation rate (ESR), and C-reactive protein (CRP) levels prior and following treatment were examined retrospectively from the patients' medical files. A decrease of 75% or more in Autoimmune Bullous Skin Disorder Intensity Score (ABSIS) was considered a remission period.

RESULTS

Among patients with PV, 78 (40.8%) were men and 113 (59.2%) were women. In patients with PV, MPV value, eosinophil, basophil count, and ESR and CRP levels showed a statistically significant decrease during the remission period, whereas alteration in platelet count was not statistically significant. Eighteen (39.1%) of patients with BP were men and 28 (60.9%) were women. In patients with BP, MPV value, eosinophil count, and ESR and CRP levels showed a statistically significant decrease during the remission period. However, platelet and basophil counts revealed no statistically significant alterations.

LIMITATIONS

Evaluation of the ABSIS scores of the followed-up patients by different observers due to the long time interval can be considered among the limitations of the study.

CONCLUSION

Eosinophils, basophils, and thrombocytes to the inflammation in the pathogenesis of PV, whereas eosinophils and thrombocytes may contribute in the pathogenesis of BP. During the activation period of autoimmune bullous diseases, the level of acute-phase reactants is higher than in the remission period.

Vortex Keratopathy as a Presenting Feature of Ocular Mucous Membrane Pemphigoid

PURPOSE

The aim of this study was to describe the presenting feature of vortex keratopathy in 3 patients with biopsy-proven ocular mucous membrane pemphigoid (OMMP).

METHODS

The first patient was a 52-year-old woman with chronic redness and foreign body sensation for 3 years who presented with unilateral vortex keratopathy. Seven months later, in the same eye, she developed conjunctival signs suggestive of OMMP. The second patient was a 33-year-old woman with similar chronic symptoms that were exacerbated by pterygium surgery. Clinical examination revealed vortex keratopathy in the right eye with subtle conjunctival signs suggestive of OMMP. The third patient was a 70-year-old woman with complaints of repeated episodes of redness and foreign body sensation for 18 months who presented with vortex keratopathy in the right eye and conjunctival signs suggestive of OMMP in the same eye. To confirm the clinical diagnosis, bilateral conjunctival biopsy was performed in all patients.

RESULTS

OMMP was diagnosed based on conjunctival signs and confirmed on direct immunofluorescence positivity, demonstrating antibodies characteristic and diagnostic of OMMP in the basement membrane zone. A unique feature that preceded or coexisted with the conjunctival signs was unilateral vortex keratopathy seen in all 3 patients, independent of the stage of the disease at which they presented.

CONCLUSIONS

Vortex keratopathy can be a presenting feature in patients with OMMP. A complete ocular surface examination, especially checking the medial canthus for keratin and the inferior fornix for foreshortening, is necessary. Conjunctival biopsy should be performed in all cases to confirm the clinical diagnosis wherever required.

The Eotaxin-1/CCR3 Axis and Matrix Metalloproteinase-9 Are Critical in Anti-NC16A IgE-Induced Bullous Pemphigoid

Bullous pemphigoid (BP) is the most common autoimmune bullous skin disease of humans and is characterized by eosinophilic inflammation and circulating and tissue-bound IgG and IgE autoantibodies directed against two hemidesmosomal proteins: BP180 and BP230. The noncollagenous 16A domain (NC16A) of BP180 has been found to contain major epitopes recognized by autoantibodies in BP. We recently established the pathogenicity of anti-NC16A IgE through passive transfer of patient-derived autoantibodies to double-humanized mice that express the human high-affinity IgE receptor, FcεRI, and human NC16A domain (FcεRI/NC16A). In this model, anti-NC16A IgEs recruit eosinophils to mediate tissue injury and clinical disease in FcεRI/NC16A mice. The objective of this study was to characterize the molecular and cellular events that underlie eosinophil recruitment and eosinophil-dependent tissue injury in anti-NC16A IgE-induced BP. We show that anti-NC16A IgEs significantly increase levels of key eosinophil chemoattractants, eotaxin-1 and eotaxin-2, as well as the proteolytic enzyme matrix metalloproteinase-9 (MMP-9) in the lesional skin of FcεRI/NC16A mice. Importantly, neutralization of eotaxin-1, but not eotaxin-2, and blockade of the main eotaxin receptor, CCR3, drastically reduce anti-NC16A IgE-induced disease activity. We further show that anti-NC16A IgE/NC16A immune complexes induce the release of MMP-9 from eosinophils, and that MMP-9-deficient mice are resistant to anti-NC16A IgE-induced BP. Lastly, we find significantly increased levels of eotaxin-1, eotaxin-2, and MMP-9 in blister fluids of BP patients. Taken together, this study establishes the eotaxin-1/CCR3 axis and MMP-9 as key players in anti-NC16A IgE-induced BP and candidate therapeutic targets for future drug development and testing.

Case Report: The many faces of bullous pemphigoid

The pemphigoid group comprises a number of bullous skin diseases with autoantibodies against different constituents of the basement membrane zone that result in subepidermal detachment and clinically characteristic tense blisters, erosions, urticarial erythema, and itching. Apart from the most frequent type of bullous pemphigoid with antibodies against BP180, which is found predominantly in elderly patients, the disease may present at other ages and different pathogenic conditions. Here, four cases are presented of young age (3 months and 25, 34, and 46 years) and in association with vaccination, pregnancy, or metastatic cancer. Though anti-BP180 was found in all cases, a different pathogenic background may be found in any of them, resulting in characteristic clinical manifestation, yet demanding specifically adapted therapeutic approaches.

Neutrophil-to-lymphocyte ratio and platelet-to-lymphocyte ratio are positively correlated with disease activity of bullous pemphigoid

Bullous pemphigoid (BP) is a complex inflammatory process with elevated levels of autoantibodies, eosinophils, neutrophils, and various cytokines. Hematological inflammatory biomarkers can reflect inflammatory state in various diseases. Up to now, the correlations of hematological inflammatory biomarkers and disease activity of BP remain unknown. The purpose of this study was to clarify the associations between hematological inflammatory biomarkers and disease activity of BP. The levels of neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR), platelet-to-neutrophil ratio (PNR) and mean platelet volume (MPV) of 36 untreated BP patients and 45 age and gender matched healthy controls were detected by routine blood tests. The correlations between hematological inflammatory markers and clinical characteristics of BP were statistically analyzed. The Bullous Pemphigoid Disease Area Index (BPDAI) was used to measure disease activity of BP. The mean levels of NLR, PLR, PNR and MPV in 36 untreated BP patients were 3.9, 157.9, 45.7 and 9.4 fl, respectively. Increased NLR (p < 0.001), PLR (p < 0.01), and MPV (p < 0.001) but decreased PNR (p < 0.001) were observed in BP patients when compared with healthy controls. In BP patients, the levels of NLR were positively correlated to BPDAI Erosion/Blister Scores (p < 0.01); and the levels of NLR and PLR were both positively correlated to BPDAI without Damage Score (both p < 0.05) and BPDAI Total Score (both p < 0.05). No correlation was found in other statistical analyses between hematological inflammatory markers and clinical characteristics in BP patients involved in the present study. Therefore, NLR and PLR are positively correlated with disease activity of BP.

Detection of a natural antibody targeting the shed ectodomain of BP180 in mice

BACKGROUND

Pemphigoid diseases are characterized by subepidermal blister formation accompanied by autoantibodies targeting skin component molecules, such as BP180. It is suggested that an epitope-phenotype correlation exists among autoantibodies recognizing BP180. However, it is unclear which regions of BP180 are likely targets for autoantibodies.

OBJECTIVE

To elucidate the portions of BP180 where antibodies tend to react under the breakdown of immune tolerance.

METHODS

We immunized mice with full-length mouse BP180 (mBP180) to produce anti-mBP180 antibodies. Using the immunized mice, hybridoma cells were established to produce anti-mBP180 antibodies. We analyzed the characteristics of the anti-mBP180 antibodies that were produced in terms of epitopes, immunoglobulin subclasses, and somatic hypermutations.

RESULTS

Hybridoma cells derived from immunized mice with full-length mBP180 produced antibodies targeting the intracellular domain (IC) and the shed ectodomain (EC) of mBP180. Using the domain-deleted mBP180 recombinant protein, we revealed that monoclonal anti-mBP180 EC antibodies react to neoepitopes on the 13th collagenous region of cleaved mBP180, which corresponds to the epitopes of linear IgA bullous dermatosis antibodies in human BP180. Furthermore, the subclasses of these antibodies could be distinguished by epitope: The subclass of the anti-mBP180 IC monoclonal antibodies was IgG, whereas that of the anti-mBP180 EC antibodies was IgM. Of note, a clone of these IgM mBP180 EC antibodies was a germline antibody without somatic hypermutation, which is also known as a natural antibody.

CONCLUSION

These data suggest that mice potentially have natural antibodies targeting the neoepitopes of cleaved mBP180 EC.

Eosinophil-derived galectin-10 upregulates matrix metalloproteinase expression in bullous pemphigoid blisters

BACKGROUND

Bullous pemphigoid (BP) is an autoimmune bullous disease in which abundant eosinophils accumulate in the blisters. Galectin-10 abounds in the cytoplasm of eosinophils and is released as a result of eosinophil extracellular trap cell death (EETosis).

OBJECTIVE

To identify EETosis and the pathological roles of galectin-10 in BP.

METHODS

EETosis and galectin-10 in BP blisters were confirmed by immunofluorescence and transmission electron microscopy. The concentrations of galectin-10 in serum and blister fluid from BP patients were studied by ELISA. The matrix metalloproteinase (MMP) expression in BP blisters was immunohistochemically compared to that in healthy controls. As an in vitro assay, normal human epidermal keratinocytes (NHEKs) and normal human dermal fibroblasts (NHDFs) were stimulated with galectin-10, followed by MMP expression measurement by real-time PCR and ELISA. The signaling pathways activated by galectin-10 were studied using Western blotting and confirmed by inhibition assays.

RESULTS

Galectin-10-containing eosinophil infiltration and the extracellular deposition of major basic protein were observed in BP blisters. The ultrastructural characteristics of tissue eosinophils indicated piecemeal degranulation and EETosis. In the BP patients, the concentration of galectin-10 was higher in the blister fluid than in the serum. Several types of MMPs were upregulated in BP blisters. Galectin-10 upregulated the production of MMPs through the pathways of p38 MAPK, ERK and JNK in NHEKs and NHDFs.

CONCLUSION

In the BP blisters, the eosinophils underwent EETosis and released galectin-10. Galectin-10 might contribute to BP blister formation through the production of MMPs by keratinocytes and fibroblasts.

Paraneoplastic autoimmune Laminin-332 syndrome (PALS): Anti-Laminin-332 mucous membrane pemphigoid as a prototype

IMPORTANCE

Laminin-332 is an important component of the basement membrane. Recently, autoantibodies to Laminin-332 have been described in several autoimmune diseases. Many of these autoimmune diseases have a high incidence of malignancy. The importance of Laminin-332 autoantibodies and its relationship to malignancy is highlighted by using Laminin-332 Pemphigoid (LM-332Pg) as a prototype.

OBJECTIVE

To identify several autoimmune diseases that have autoantibodies to Laminin-332 present, and to determine the prevalence of malignancy in them. Using Laminin-332 Pemphigoid (LM-332Pg) as a prototype, to compare clinical profiles of LM-332Pg patients with and without cancer. By identifying the temporal detection of cancer, can the influence of autoantibodies to Laminin-332 on prognosis be determined.

EVIDENCE REVIEW

A literature search was conducted to identify autoimmune and inflammatory diseases in which autoantibodies to Laminin-332 were present. Subsequently, the rate of malignancy in these autoimmune diseases was determined. A search for publications on LM-332Pg patients to determine cancer rates and clinical outcomes to examine if a relationship can be proposed, was performed.

FINDINGS

Autoantibodies to Laminin-332 were detected in recent studies of systemic lupus erythematosus (SLE), psoriasis, bronchiolitis obliterans (BO), graft-vs-host disease (GVH), bullous pemphigoid (BP), lichen planus (LP), epidermolysis bullosa acquisita (EBA), and membranous glomerulonephropathy (MGN). A high incidence of cancer rate was reported in these autoimmune diseases including primary Sjögren's syndrome (pSS), systemic sclerosis (SS), dermatomyositis (DM), multiple sclerosis (MS), immune thrombocytopenia purpura (ITP), and rheumatoid arthritis (RA). Data analysis demonstrated that LM-332Pg patients had a higher risk of developing ovarian, uterine, lung, gastric cancers and leukemia. The incidence for breast cancer was lower, when compared with global cancer rates. Patients diagnosed with cancer after the presence of LM-332Pg had higher rates of mortality and lower rates of remission, compared to those diagnosed with cancer prior to the discovery/diagnosis of LM-332Pg. When studied, levels of Laminin-332 autoantibodies correlated with the presence or absence of malignancy.

CONCLUSIONS AND RELEVANCE

Preliminary analysis suggests that autoantibodies to Laminin-332 are present in multiple autoimmune diseases, which also have a high incidence of malignancy. Detailed analysis of available data highlights that patients who developed LM-332Pg after cancer was diagnosed, had a more favorable prognosis, compared to patients who developed cancer when LM-332Pg was previously present. Preliminary data would suggest that autoantibodies to Laminin-332 could serve as an important biomarker in certain patients, for correlation with possible incidence of malignancy.

Autoimmune bullous disorder flares following severe acute respiratory syndrome coronavirus 2 vaccination: a case series

BACKGROUND

Autoimmune bullous disorders develop due to autoantibodies targeting intercellular adhesion proteins of hemidesmosomes and desmosomes and may be triggered by viral infections and vaccines. Recent reports suggest that the coronavirus disease 2019 vaccination may trigger flares or exacerbations of preexisting autoimmune diseases, including new onset autoimmune bullous disorders. There are less data on whether vaccination against severe acute respiratory syndrome coronavirus 2 may also exacerbate preexisting autoimmune bullous disorders.

CASE PRESENTATION

Here we present three cases, two white males (ages 69 years and 88 years) with bullous pemphigoid and one white 50-year-old female with pemphigus foliaceus, wherein all individuals developed minor, tractable flares of their preexisting autoimmune bullous disorders after receiving the coronavirus disease 2019 vaccination, which were readily treatable with topical or low-dose systemic corticosteroids.

CONCLUSIONS

Dermatologists managing patients with autoimmune bullous disorders should be cognizant of the uncommon potential for flares of the disorder following vaccination for severe acute respiratory syndrome coronavirus 2. Flares of bullous pemphigoid and pemphigus foliaceus following vaccination for severe acute respiratory syndrome coronavirus 2 in these cases were mild and tractable.

Usefulness of immunofluorescence overlay antigen mapping in the identification of autoantigen in anti-p200 pemphigoid

Anti-p200 pemphigoid is a rare subepidermal blistering disease showing immunoglobulin G (IgG) autoantibodies reactive with a 200-kDa protein. In most patients, serum IgG antibodies react with laminin γ1. The diagnosis of anti-p200 pemphigoid is occasionally difficult, mainly due to the lack of standardized tests. We performed fluorescence overlay antigen mapping by laser scanning confocal microscopy (FOAM-LSCM) to identify autoantigens in an anti-p200 pemphigoid patient and assessed its usefulness for the diagnosis. A 71-year-old man presented with blisters and erosions on the bilateral forearms. No mucosal lesions were observed. Laboratory examinations revealed mild leukocytosis and antinuclear antibody negativity. A histopathological examination showed subepidermal blisters with neutrophil infiltration. Direct immunofluorescence showed linear IgG staining along the basement membrane zone. Indirect immunofluorescence using 1 M NaCl-split skin sections revealed IgG reactivity on the dermal side. Immunoblotting detected circulating IgG autoantibodies that reacted with a 200-kDa protein. Accordingly, anti-p200 pemphigoid was diagnosed. FOAM-LSCM revealed that the patient's IgG signals were co-localized with laminin γ1 but were observed above type VII collagens. A direct immunofluorescent analysis for IgG deposition patterns showed an n-serrated pattern. Thus, FOAM-LSCM may be useful for diagnosing anti-p200 pemphigoid.

Divergent in situ expression of IL-31 and IL-31RA between bullous pemphigoid and pemphigus vulgaris

Bullous pemphigoid (BP) and pemphigus vulgaris (PV) are two major autoimmune blistering skin diseases. Unlike PV, BP is accompanied by intense pruritus, suggesting possible involvement of the pruritogenic cytokine IL-31. However, the underlying mechanisms of the clinical difference between BP and PV in terms of pruritus are not fully understood. To compare the expression levels of IL-31 and its receptor IL-31RA in the lesional skin, including peripheral nerves in BP and PV patients, immunohistochemical staining for IL-31 and IL-31RA was performed in skin samples of BP and PV patients and healthy controls (HC). The IL-31RA-expressing area in epidermis and peripheral nerves was analysed using ImageJ and the percentage of positive cells for IL-31/IL-31RA in dermal infiltrating cells was manually quantified. Quantitative analyses revealed that IL-31/IL-31RA expressions in the epidermis and dermal infiltrate were significantly increased in BP compared to PV and HC. The difference between BP and PV became more obvious when advanced bullous lesions were compared. Peripheral nerves in BP lesions presented significantly higher IL-31RA expression compared to PV lesions. In conclusion, we found significantly augmented expressions of IL-31/IL-31RA in BP lesions, including peripheral nerves, in comparison to PV. These results suggest a possible contribution of IL-31/IL-31RA signalling to the difference between BP and PV in the facilitation of pruritus and local skin inflammation, raising the possibility of therapeutic targeting of the IL-31/IL-31RA pathway in BP patients.

Analysis of IL-10 and IL-35 in dipeptidyl peptidase-4 inhibitor-related bullous pemphigoid

The association between immunoregulatory cytokines, such as interleukin (IL)-10 or IL-35, and dipeptidyl peptidase-4 inhibitor (DPP4i)-related bullous pemphigoid (BP) has not been evaluated. Serum IL-10 and IL-35 levels were measured in 39 patients with BP (24 males and 15 females; 6 DPP4i-related and 33 DPP4i-unrelated BP patients) and 10 healthy controls. The number of CD26+ cells in the dermis around bulla on sections was counted immunohistochemically for 12 patients (six patients with DPP4i-related BP and six randomly sampled patients with DPP4i-unrelated BP). Patients with DPP4i-related BP had lower levels of serum eosinophils (DPP4i-related vs. DPP4i-unrelated BP: 476.1 ± 234.0 vs. 911.3 ± 948.8/μL; p = 0.537) and a higher rate of infiltrating CD26+ cells (32.9 ± 7.1% vs. 15.7 ± 4.4%; p = 0.01). There were no significant differences in serum IL-10 (6.77 ± 0.24 vs. 6.84 ± 0.20 pg/mL), serum IL-35 (2.63 ± 0.17 vs. 2.63 ± 0.21 pg/mL), serum anti-BP180NC16a antibodies (67.31 ± 37.4 vs. 76.18 ± 54.59 U/mL) and Bullous Pemphigoid Disease Area Index before treatment in this study. Serum IL-10 and IL-35 levels do not increase in patients with BP and may not be a candidate for a therapeutic target for BP. An increase in CD26+ cells might be associated with DPP4i-related BP.

Evaluation of the Diagnostic Value of Oesophageal Biopsies for Direct Immunofluorescence Microscopy in Mucous Membrane Pemphigoid

Mucous membrane pemphigoid is an autoimmune blistering disorder characterized by predominant involvement of surface-close epithelia and linear depositions of immunoreactants at the dermal-epithelial junction on direct immunofluorescence microscopy. A major diagnostic difficulty is the frequent need for multiple biopsies to facilitate the diagnosis. Although oesophageal involvement is a rare, but life-threatening manifestation, the relevance of oesophageal direct immunofluorescence sampling is unclear. This retrospective monocentric study evaluated 67 non-lesional biopsies from 11 patients with mucous membrane pemphigoid and clinical symptoms suggestive of oesophageal involvement, comprising 31 samples from the oesophagus and 36 samples from other anatomical sites. Five patients (45.5%) exhibited endoscopic findings compatible with oesophageal involvement of mucous membrane pemphigoid. No correlation was identified between the presence of oesophageal lesions and direct immunofluorescence positivity in lesions from the oesophagus (p = 1.0). Oral and cutaneous samples were significantly more frequently positive by direct immunofluorescence than were oesophageal biopsies (p < 0.0001 and p = 0.0195, respectively). Oesophageal samples yielded significantly less IgG reactivity than oral and cutaneous lesions (p < 0.0001 and p = 0.0126, respectively), and less IgA antibody response than oral lesions (p = 0.0036). In conclusion, oesophageal direct immunofluorescence samples were inferior to oral and cutaneous biopsies for the diagnosis of mucous membrane pemphigoid even when oesophageal lesions compatible with mucous membrane pemphigoid were present at the time of biopsy.

Autoimmunity against laminin 332

Laminin 332 is a heterotrimeric structural protein of the basal membrane zone (BMZ) of the skin and adjacent mucosal tissues. The importance of laminin 332 for the structural integrity of the BMZ is demonstrated by mutations in any of the three genes encoding for its three chains causing variants of junctional epidermolysis bullosa. Autoimmunity against laminin 332 is observed in mucous membrane pemphigoid (MMP) and in the rare patients with orf-induced pemphigoid. MMP is an autoimmune blistering disease with predominant mucosal manifestations and autoantibodies against the BMZ of the skin and orifice-close mucous membranes. The main autoantigens of MMP are type XVII collagen (BP180) and laminin 332 targeted in about 80% and 10-20% of patients, respectively. An increasing number of studies has highlighted the association of anti-laminin 332 MMP and malignancies that can be revealed in about a quarter of these patients. This data has led to the recommendation of current guidelines to assay for anti-laminin 332 reactivity in all MMP patients. The present review focuses on anti-laminin 332 MMP describing clinical features, its pathophysiology, and detection of serum anti-laminin 332 IgG. In addition, the available data about the occurrence of malignancies in anti-laminin 332 MMP, the underlying tumor entities, and its biology are detailed.

Pilot study investigating BP-180 in extracellular vesicles derived from blister fluid of bullous pemphigoid patients

Bullous pemphigoid (BP) is an autoimmune blistering disease that targets the haemidesmosomal proteins, mainly BP180. Extracellular vesicles (EVs) have been demonstrated to carry tissue-specific autoantigens in the setting of autoimmune diseases and transplant organ rejection; this phenomenon was demonstrated to have pathogenic implications in autoimmune diseases and to correlate with transplant rejection severity. The purpose of this study was to identify the presence of BP targeted autoantigens in blister fluid derived EVs. We isolated, by size exclusion chromatography, EVs derived from blisters of BP-patients and from suction blisters of healthy donors. EV characterization was performed by flow cytometry and nanoparticle tracking analysis. Western blot analysis was used to investigate the presence of autoantigens. A suspension enriched in EVs was efficiently obtained from blister fluid from patients and healthy donors. EV-enriched fractions were enriched in particles with a size distribution characterizing small-EVs (main peak was present at 94.5 nm). BP180 was found, by western blot analysis, in EVs derived from blister fluid of 3 out 6 BP patients and in none of EVs isolated from suction blister fluid of healthy donors. BP230 and Dsg1 were not detectable in EVs of any of the samples. No specific clinical characteristics seemed to correlate to the presence of BP180 in EVs. The discovery of BP180 in EVs derived from blister fluid might help understanding BP pathogenesis.

Autoimmune skin disorders and SARS-CoV-2 vaccination - a meta-analysis

BACKGROUND AND OBJECTIVES

The coronavirus SARS-CoV-2, which is the cause of COVID-19 disease in infected patients, has led to an ongoing worldwide pandemic. Although SARS-CoV-2 vaccination had a dramatic positive effect on the course of COVID-19, there has been increasing evidence of adverse effects after SARS-CoV-2 vaccination. This meta-analysis highlights the association between SARS-CoV-2 vaccination and de novo induction or aggravation of inflammatory and autoimmune skin diseases.

MATERIAL AND METHODS

A systematic meta-analysis of the literature on new onset or worsening of inflammatory and autoimmune diseases after SARS-CoV-2 vaccination was performed according to the PRISMA guidelines. The search strategy included following terms: "COVID-19/SARS-CoV-2 vaccine bullous pemphigoid/pemphigus vulgaris/systemic lupus erythematosus/dermatomyositis/lichen planus/leukocytoclastic vasculitis." Moreover, we describe representative cases from our dermatology department.

RESULTS

The database-search in MEDLINE identified 31 publications on bullous pemphigoid, 24 on pemphigus vulgaris, 65 on systemic lupus erythematosus, nine on dermatomyositis, 30 on lichen planus, and 37 on leukocytoclastic vasculitis until June 30th, 2022. Severity and response to treatment varied among the described cases.

CONCLUSIONS

Our meta-analysis highlights a link between SARS-CoV-2 vaccination and new onset or worsening of inflammatory and autoimmune skin diseases. Moreover, the extent of disease exacerbation has been exemplified by cases from our dermatological department.

Dupilumab effectively and rapidly treats bullous pemphigoid by inhibiting the activities of multiple cell types

Background

Bullous pemphigoid (BP) is an autoimmune skin-blistering disease. Systemic corticosteroids remain the first line treatment for moderate-to-severe BP with the potential for severe adverse events. Dupilumab has emerged as an alternative option for BP patients.

Objective

We evaluated the efficiency and safety of dupilumab on BP treatment and explored a mode of drug action in depth.

Methods and results

A multicenter retrospective cohort included 20 BP patients who received dupilumab with or without systemic corticosteroid in dupilumab group, and 20 matched BP patients who received corticosteroid alone in conventional group. Serum samples were collected from 20 patients (10 from dupilumab group and 10 from conventional group) at baseline and week 4. Compared to systemic corticosteroid alone, dupilumab with or without systemic corticosteroid was similarly efficacious in clinical remission at week4 (complete remission plus partial remission: 100%) and week24 (complete remission plus partial remission:100%), but allowing significant decreases in the cumulative doses of corticosteroids with reducing the incidence of adverse events. However, dupilumab did not decrease BP180 antibody despite an obvious clinical improvement. Comparative plasma proteomic analysis performed before and after treatment in 3 BP patients from dupilumab group revealed that drug use was associated with 30 differentially expressed proteins, including 26 down-regulated and 4 up-regulated proteins. The former consisted of immune related proteins involved in T/B cell interactions (inducible T-cell co-stimulator ligand, ICOSL) and in the activation of eosinophils (PRG2), mast cells (S100A12), and complement (CR2). TARC and ICOSL levels correlated with BP severity in patients who received either dupilumab or conventional treatment.

Conclusion

Dupilumab has similar efficacy in treating BP as conventional drugs, by inhibiting the activities of many types of immune cells and complement, and regulating the interactions between T and B cells.

[Ocular mucous membrane pemphigoid]

Mucous membrane pemphigoid refers to a heterogeneous group of autoimmune diseases with subepidermal blister formation that can affect all mucous membranes with varying frequencies. This is a rare disease without any geographic or sexual predisposition that is characterized by recurrent inflammation and progressive scarring. The specific diagnostics can be negative in up to 50% of cases. The diagnosis is predominantly made in patients aged 60-80 years. Ophthalmologists play an important role in the care of affected individuals as the conjunctiva is the second most frequent site of involvement. The treatment is often tedious and primarily consists of long-term systemic immunosuppression.

Skin-infiltrating T cells display distinct inflammatory signatures in lichen planus, bullous pemphigoid and pemphigus vulgaris

Introduction

We here thought to dissect the inflammatory signature in lesions of three skin disorders, which show a common adaptive immune response against autoantigens of the skin but are characterized by diverging clinical phenotypes. Pemphigus vulgaris (PV) and bullous pemphigoid (BP) are type-2-dependent, IgG autoantibody-driven blistering disorders of mucous membranes and skin, which target desmoglein (Dsg)3 and bullous pemphigoid (BP)180, respectively. In contrast, lichen planus (LP) is a common chronic inflammatory disease of the skin and mucous membranes with a pronounced dermal T cell infiltrate. We previously identified peripheral type 1 and 17 T cell responses against Dsg3 and BP180 in a cohort of LP patients strongly suggesting that the underlying inflammatory T cell signature may drive the evolving phenotype.

Methods

Paraffin-embedded skin biopsies from well-characterized patients with LP (n=31), BP (n=19), PV (n=9), and pemphigus foliaceus (PF) (n=2) were analysed. Areas with the most prominent inflammatory infiltrate were excised with punch biopsies and tissue microarrays (TMA) containing multiple biopsies were created. Using multicolor immunofluorescence, the inflammatory infiltrate was stained with antibodies against multiple cellular markers, i. e. CD3ϵ, CD4, CD15, TCR-δ, the cytokine IL-17A, and the transcription factors, T-bet and GATA-3.

Results

In LP, there was a higher number of CD4+ T cells expressing T-bet compared to GATA-3. In contrast, CD4+ T cells in PV and BP skin lesions more frequently expressed GATA-3 than T-bet. IL-17A+ cells and IL-17A+ T cells were found to a similar extent in all the three disorders. IL-17A+ granulocytes were more predominant in BP than in LP or PV. Of note, the majority of IL-17A+ cells in LP were neither T cells nor granulocytes.

Discussion

Our findings in inflammatory skin infiltrates clearly show a predominant type 1 signature in LP in contrast to a preponderance of type 2 T cells in PV and BP. In contrast to LP, granulocytes and to a much lesser extent CD3+ T cells were a cellular source of IL-17A in BP and PV. These data strongly suggest that different inflammatory cell signatures drive evolving clinically diverse phenotypes of LP, PV and BP despite common target antigens of the skin.

Research progress of omalizumab in the treatment of bullous pemphigoid

Bullous pemphigoid (BP) is an autoimmune blistering disease associated with anti-BP180 and anti-BP230 antibodies. The pathogenic action mechanism of immunoglobulin E (IgE) antibodies in BP has been studied since the 1970s, and IgE antibodies have gradually been confirmed as being important in BP; therefore, anti-IgE therapy may be a new option for the treatment of BP. Omalizumab, as an IgE monoclonal antibody, has been increasingly used clinically to treat BP in recent years. Here, we collected 35 papers investigating omalizumab for BP treatment in a total of 83 patients, and the vast majority of patients showed varying degrees of improvement after treatment, except for a small number of patients with poor clinical outcomes. The patients were then divided into three groups according to dosing frequency and number of doses. Statistical analysis indicated that dosing frequency had little effect on clinical efficacy. While the groups with different numbers of doses were evaluated, the results concluded that clinical efficacy was affected by the number of doses, but there was no positive correlation between the number of doses and clinical efficacy.

Adaptive and innate immune pathogenesis of bullous pemphigoid: A review

Bullous pemphigoid (BP) is an autoimmune blistering disease that primarily affects elderly individuals. The presentation of BP is heterogeneous, typically manifesting as microscopic subepidermal separation with a mixed inflammatory infiltrate. The mechanism of pemphigoid development is unclear. B cells play a major role in pathogenic autoantibody production, and T cells, type II inflammatory cytokines, eosinophils, mast cells, neutrophils, and keratinocytes are also implicated in the pathogenesis of BP. Here, we review the roles of and crosstalk between innate and adaptive immune cells in BP.

Case report: Mucous membrane pemphigoid with complicated autoantibody profile indicating the necessity of comprehensive diagnostic methods and the contribution of IgA autoantibodies

Mucous membrane pemphigoid (MMP) is a type of subepithelial autoimmune bullous disease, affecting various mucosae, occasionally with skin lesions. Both diagnosis and treatment of MMP are difficult. Although multiple autoantigens have been identified for MMP, the pathogenesis of MMP is still unclear. In this study, we presented a female MMP case with extensive oral mucosal lesions and skin lesions, particularly on the extremities. IgG and IgA autoantibodies against multiple autoantigens including BP180, laminin 332, integrinα6β4 and desmoglein 3, and IgM autoantibodies against BP180 were identified during the disease course. Compared with IgG autoantibodies, the levels of IgA autoantibodies against various autoantigens decreased more significantly with improvement of clinical features after the initiation of treatments. Our findings indicated the importance of comprehensive autoantibody screening for different immunoglobulin types and autoantigens at multiple time points for the precise diagnosis of various autoimmune bullous diseases, and the significant involvement of IgA autoantibodies into the pathogenesis of MMP.

Associations between bullous pemphigoid and hematological diseases: Literature review on mechanistic connections and possible treatments

Bullous pemphigoid is an autoimmune blistering disorder that primarily occurs in elderly patients. Reports indicate that BP coexists with various hematological diseases, including acquired hemophilia A, hypereosinophilic syndrome, aplastic anemia, autoimmune thrombocytopenia, and hematological malignancies. Early identification of these comorbidities contributes to a better control and reduced mortality. This article details the atypical clinical manifestations of BP when associated with hematological diseases, specific diagnostic strategies, underlying mechanistic connections, and possible treatments. Cross-reactivity between autoantibodies and exposed abnormal epitopes, shared cytokines and immune cells, together with genetic susceptibility are the most common connections between BP and hematological diseases. Patients were most often successfully treated with oral steroids combined with medications specifically targeting the hematological disorders. However, the individual comorbidities require specific considerations.