Immunoglobulin E-Mediated Autoimmunity

Computationally grafting an IgE epitope onto a scaffold: Implications for a pan anti-allergy vaccine design

Allergy is becoming an intensifying disease among the world population, particularly in the developed world. Once allergy develops, sufferers are permanently trapped in a hyper-immune response that makes them sensitive to innocuous substances. The immune pathway concerned with developing allergy is the Th2 immune pathway where the IgE antibody binds to its Fc ∊ RI receptor on Mast and Basophil cells. This paper discusses a protocol that could disrupt the binding between the antibody and its receptor for a potential permanent treatment. Ten proteins were computationally designed to display a human IgE motif very close in proximity to the IgE antibody's Fc ∊ RI receptor's binding site in an effort for these proteins to be used as a vaccine against our own IgE antibody. The motif of interest was the FG loop motif and it was excised and grafted onto a Staphylococcus aureus protein (PDB ID 1YN3), then the motif + scaffold structure had its sequence re-designed around the motif to find an amino acid sequence that would fold to the designed structure correctly. These ten computationally designed proteins showed successful folding when simulated using Rosetta's AbinitioRelax folding simulation and the IgE epitope was clearly displayed in its native three-dimensional structure in all of them. These designed proteins have the potential to be used as a pan anti-allergy vaccine. This work employedin silicobased methods for designing the proteins and did not include any experimental verifications.

The intervention of intestinal Wnt/β-catenin pathway alters inflammation and disease severity of CIA

Autoreactive T cell is one of the leading causes of immunological tolerance defects in the chronic inflammatory lesions of rheumatoid arthritis (RA). There have been several extracellular signals and intracellular pathways reported in regulating this process but largely remain unknown yet. In this study, we explored the roles of intestinal Wnt/β-catenin on disease severity during collagen-induced arthritis model (CIA), an animal model of RA. We first testified the activity pattern Wnt/β-catenin shifted by intragastric administration of LiCl and DKK-1 in the intestine by real-time PCR and WB analysis. The arthritis scores showing the disease severity in the DKK-1 group was significantly ameliorated compared with the control group at the late stage of the disease, while in the LiCl group, the scores were significantly elevated which was consistent with pathology score analysis of H&E staining. Next, ELISA was performed and showed that TNF-α and IL-17 in the LiCl group were significantly higher than that of the control group. IL-10 in the DKK-1 group was significantly higher than that in the LiCl-1 group and control group, P < 0.05. Flow cytometry of spleen T cells differentiation ratio showed that: Th1 from the DKK-1 and LiCl groups and Th17 from the LiCl group was significantly different from that of the blank model group, P < 0.05. Finally, we explored the effects of intestinal Wnt/β-catenin on T cell differentiation regulator ROR-γt and TCF1 and found that both transcription factors were up-regulated in the LiCl group. Together, these data suggested the pro-information role of Wnt/β-catenin pathway from the intestine in the CIA mouse, implying its use as a potential therapeutic target for the treatment of inflammatory diseases such as RA.

The Classification, Pathogenesis, Diagnostic Workup, and Management of Urticaria: An Update

Wheals and angioedema are the signature signs of urticaria, and itch is the key symptom. Urticaria, in most patients, is acute and resolves within days (acute urticaria, AU). Chronic urticaria (CU) can be of long duration and results not only in severely impaired quality of life but also has a socioeconomic impact due to work productivity impairment. In some patients with CU, the wheals and angioedema are induced exclusively by defined and definite triggers (chronic inducible urticaria, CIndU). In most patients with CU, wheals and angioedema develop unprompted, spontaneously (chronic spontaneous urticaria, CSU). The management of CU aims for the complete control and absence of its signs and symptoms. This is achieved, in most patients, by prophylactic treatment until spontaneous remission occurs. Modern, second-generation H1-antihistamines are the first-line therapy, with the option of updosing to fourfold, and omalizumab is used when this fails.

Tuning IgE: IgE-Associating Molecules and Their Effects on IgE-Dependent Mast Cell Reactions

The recent emergence of anti-immunoglobulin E (IgE) drugs and their candidates for humans has endorsed the significance of IgE-dependent pathways in allergic disorders. IgE is distributed locally in the tissues or systemically to confer a sensory mechanism in a domain of adaptive immunity to the otherwise innate type of effector cells, namely, mast cells and basophils. Bound on the high-affinity IgE receptor FcεRI, IgE enables fast memory responses against revisiting threats of venoms, parasites, and bacteria. However, the dysregulation of IgE-dependent reactions leads to potentially life-threatening allergic diseases, such as asthma and anaphylaxis. Therefore, reactivity of the IgE sensor is fine-tuned by various IgE-associating molecules. In this review, we discuss the mechanistic basis for how IgE-dependent mast cell activation is regulated by the IgE-associating molecules, including the newly developed therapeutic candidates.

Chronic urticaria in children - New insights from a large cohort

BACKGROUND

Chronic spontaneous urticaria is well-described in adults, but less so in children. The aim of this study is to describe the demographics, clinical characteristics, comorbidities, and outcomes of children with chronic, spontaneous urticaria.

METHODS

This retrospective study followed children up to 18 years old, diagnosed with chronic spontaneous urticaria, between the years 2002-2018, and treated in a tertiary referral allergy and clinical immunology center. Data including demographics, clinical characteristics, comorbidities, treatments, and outcomes were extracted from electronic medical records.

RESULTS

Records of 380 children coded to have chronic urticaria were reviewed, of which 250 (65.8%) fulfilled the diagnostic criteria for chronic spontaneous urticaria. There were 136 females (54.4%). Mean age at diagnosis was 11.4 years, and 122 (48%) were adolescents. The average duration of chronic spontaneous urticaria was 12.25 ± 15.2 months. The urticaria in 208 children )83.2%) resolved within 24 months. Eighty-seven patients (34.8%) had at least one atopic disease. Atopic comorbidities included atopic dermatitis in 17.2%, allergic rhinitis in 16%, asthma in 13.2%, and food allergy in 3.2%. Eighteen patients (7.2%) had a concomitant autoimmune disease. Nine (3.6%) had thyroid disease.

CONCLUSIONS AND CLINICAL RELEVANCE

Chronic spontaneous urticaria in children is a self-limited disease with favorable prognosis. Atopic diseases are more prevalent in children with chronic spontaneous urticaria than in the general pediatric population, increasing the possibility of a special subgroup of TH2-related chronic urticaria in children.

The role of CD23 in the regulation of allergic responses

IgE, the key molecule in atopy has been shown to bind two receptors, FcεRI, the high‐affinity receptor, and FcεRII (CD23), binding IgE with lower affinity. Whereas cross‐linking of IgE on FcεRI expressed by mast cells and basophils triggers the allergic reaction, binding of IgE to CD23 on B cells plays an important role in both IgE regulation and presentation. Furthermore, IgE‐immune complexes (IgE‐ICs) bound by B cells enhance antibody and T cell responses in mice and humans. However, the mechanisms that regulate the targeting of the two receptors and the respective function of the two pathways in inflammation or homeostasis are still a matter of debate. Here, we focus on CD23 and discuss several mechanisms related to IgE binding, as well as the impact of the IgE/antigen‐binding on different immune cells expressing CD23. One recent paper has shown that free IgE preferentially binds to FcεRI whereas IgE‐ICs are preferentially captured by CD23. Binding of IgE‐ICs to CD23 on B cells can, on one hand, regulate serum IgE and prevent effector cell activation and on the other hand facilitate antigen presentation by delivering the antigen to dendritic cells. These data argue for a multifunctional role of CD23 for modulating IgE serum levels and immune responses.

The challenges of chronic urticaria part 2: Pharmacological treatment, chronic inducible urticaria, urticaria in special situations

This is Part 2 of an updated follow-up review of the World Allergy Organization (WAO) position paper on the diagnosis and treatment of urticaria and angioedema. Since that document was published, new advances in the understanding of the pathogenesis of chronic urticaria, and greater experience with the use of biologics in patients with severe refractory disease, mainly omalizumab, have been gained. For these reasons, WAO decided to initiate an update targeted to general practitioners around the world, incorporating the most recent information on epidemiology, immunopathogenesis, comorbidities, quality of life, clinical case presentations, and the management of chronic spontaneous and chronic inducible urticaria, and urticaria in special situations such as childhood and pregnancy. A special task force of WAO experts was invited to write the different sections of the manuscript, and the final document was approved by the WAO Board of Directors. This paper is not intended to be a substitute for current national and international guidelines on the management of urticaria and angioedema, but to provide an updated simplified guidance for physicians around the world who have to manage patients with this common ailment.

Subcutaneous panniculitis-like T-cell lymphoma, lupus erythematosus profundus, and overlapping cases: molecular characterization through the study of 208 genes

Subcutaneous panniculitis-like T-cell lymphoma (SPTCL) is a rare cytotoxic cutaneous lymphoma. Differential diagnosis with lupus erythematosus panniculitis (LEP) can be challenging and overlapping cases have been described. In this study, we investigate whether gene expression profiling may or not identify markers that can be used to improve our understanding of the disease and to make a precise differential diagnosis. SPTCL, LEP, and overlapping cases were analyzed using a customized NanoString platform including 208 genes related to T-cell differentiation, stromal signatures, oncogenes, and tumor suppressor genes. Gene expression unsupervised analysis of the samples differentiated SPTCL from LEP samples. Most overlapping cases were clustered with LEP cases. Differentially expressed genes were observed when comparing SPTCL with LEP cases; and overlapping with LEP cases. Gene set enrichment analysis recognized gene sets defining each group. In conclusion, SPTCL and LEP have distinctive molecular profiles and the molecular background of overlapping cases more closely resembles LEP.

Autoimmunity, IgE and FcεRI-bearing cells

Antibody-mediated autoimmune diseases (AAID) involve several isotypes of autoreactive antibodies. In a growing number of AAID, autoreactive IgE are present with a significant prevalence and are often associated with the presence of IgG anti-IgE and/or anti-FcεRIα (high affinity IgE receptor α chain). FcεRI-bearing cells, such as basophils or mast cells, are key players in some of these AAID. Recent advances in the pathophysiology of these diseases led to the passed or current development of anti-IgE strategies that showed very potent effects in some of them. The present review centralizes the information on the relevance of autoreactive IgE and FcεRI-bearing cells in the pathophysiology of different AAID and the ones where the anti-IgE therapeutic strategy shows or may show some benefits for the patients.

THYROTROPIN-RECEPTOR ANTIBODIES, IMMUNOGLOBULIN E AND ANTINUCLEAR ANTIBODIES IN PATIENTS WITH GRAVES' DISEASE AND GRAVES' ORBITOPATHY

CONTEXT

Thyrotropin-receptor antibodies (TRAb) are biomarkers of Graves' disease (GD) and Graves' orbitopathy (GO). Elevated immunoglobulin E (IgE) and antinuclear antibodies (ANA) were also found in GD patients.

OBJECTIVE

We aimed to assess TRAb, IgE and ANA in GD and GO patients and to evaluate the relationship between the immunological markers and smoking.

DESIGN

This was a comparative cross-sectional study carried out in a single tertiary care center from June 2018 to January 2020.

SUBJECTS AND METHODS

A total of 103 GD patients (mean age 51.2, 84 females) were divided into three subgroups: moderate-to-severe GO (n=36), mild GO (n=32) and "only GD" subgroup (n=35). Forty healthy controls (HC) (mean age 51.2, 36 females) were also included. TRAb were measured by a thyrotropin-binding inhibitory immunoglobulin (TBII) assay in GD patients; IgE and ANA - by an enzyme-linked immunosorbent assay in all subjects.

RESULTS

GD patients had higher IgE-positivity rate (p=0.04) and similar ANA-positivity compared to HC. Moderate-to-severe GO subgroup had the highest TBII (p<0.01), the lowest TBII-negativity rate (p<0.01) and the highest ANA-positivity rate (p=0.03) and was the only subgroup whose IgE-positivity rate was significantly higher than HC (25% vs. 7.5%). Mild GO and "only GD" patients had comparable TBII, TBII-negativity rate, IgE and ANA.Both GO subgroups had significantly higher smoking rate than "only GD" patients. Smoking was positively associated with IgE positivity (φ=0.22, p=0.03), and negatively with TBII negativity rate (φ=-0.24, p=0.02).

CONCLUSIONS

GD patients exhibit different immunological patterns depending on the presence and severity of GO. Smoking might be just one of the factors responsible for the clinical and immunological variety of GD. Further studies are needed.

Cytokines that Modulate the Differentiation of Th17 Cells in Autoimmune Uveitis

Increasing evidence has suggested that T helper 17 (Th17) cells play a central role in the pathogenesis of ocular immune disease. The association between pathogenic Th17 cells and the development of uveitis has been confirmed in experimental and clinical studies. Several cytokines affect the initiation and stabilization of the differentiation of Th17 cells. Therefore, understanding the mechanism of related cytokines in the differentiation of Th17 cells is important for exploring the pathogenesis and the potential therapeutic targets of uveitis. This article briefly describes the structures, mechanisms, and targeted drugs of cytokines-including interleukin (IL)-6, transforming growth factor-β1 (TGF-β1), IL-1β, IL-23, IL-27, IL-35, IL-2, IL-4, IL-21, and interferon (IFN)-γ-which have an important influence on the differentiation of Th17 cells and discusses their potential as therapeutic targets for treating autoimmune uveitis.

A History of Asthma Increases the Risk of Bullous Pemphigoid: Insights from a Large Population-Based Study

BACKGROUND

Bullous pemphigoid (BP) and asthma both share a pathogenic role of eosinophils and immunoglobulin E (IgE) and favorable response for corticosteroids and omalizumab. However, the association between these conditions is yet to be investigated. We sought to estimate the risk of having BP among patients previously diagnosed with asthma and to characterize patients with coexistent BP and asthma.

METHODS

Utilizing the dataset of Clalit Health Services, a population-based case-control study was conducted comparing BP patients (n = 3,924) with age-, sex-, and ethnicity-matched control subjects (n = 19,280) regarding the presence of asthma. Logistic regression models were utilized for univariate and multivariate analyses.

RESULTS

The prevalence of preceding asthma was higher in patients with BP than in control subjects (11.1 vs. 7.9%, respectively; p < 0.001). A history of asthma was associated with a 50% increase in the risk of BP (OR 1.45; 95% CI 1.30-1.62). The association was not altered greatly after adjusting for demographics (adjusted OR 1.43; 95% CI 1.28-1.61) as well as for demographics and comorbidities (adjusted OR 1.40; 95% CI 1.25-1.57). The average (SD) latency between the diagnosis of asthma and the development of BP was 12.5 (14.7) years. When compared with other patients with BP, those with a dual diagnosis of BP and asthma were older, had higher BMI, and were more frequently managed by corticosteroids and immunosuppressive and immunomodulatory adjuvants.

CONCLUSIONS

Asthma confers a predisposition to the development of BP. Awareness of this association may be of help for physicians managing patients with BP and asthma. Further research is required to elucidate the mechanism underlying this observation.

Anti-IgE for the Treatment of Chronic Urticaria

Urticaria and angioedema are very common. Management of chronic urticaria subtypes, which usually persist for many years, is challenging. Recent years have demonstrated that targeting IgE with antibodies provides a safe and efficient treatment approach. Whilst several anti-IgE antibodies have been developed, omalizumab is currently the only one approved for use. International and national guidelines recommend its use after failure of antihistamines at standard and increased dose. Whilst not yet approved, many new anti-IgE approaches are currently being investigated in pre-clinical studies or clinical trials. This non-systematic focused review summarizes current knowledge of omalizumab and other anti-IgE biologics in chronic urticaria using data extracted from PubMed, Google Scholar and clinical trial databases, clinicaltrials.gov and clinicaltrials.eu. For adults, there is good evidence from randomized clinical trials and real-world data that symptomatic treatment with omalizumab is efficacious and safe in chronic spontaneous urticaria (CSU), whereas evidence in chronic inducible urticaria (CINDU) and special populations is limited. Easy-to-use tools to identify non-responders and predict the required duration of treatment have not been established yet. Phase 2 b results of ligelizumab have not only demonstrated efficacy and safety but also superiority to omalizumab. Indeed, there is preliminary evidence that omalizumab non- or partial responders benefit from ligelizumab. Whereas further development of quilizumab was discontinued, other approaches, eg UB-221 or DARPins are under investigation. Anti-IgE treatment with omalizumab represents a landmark in the treatment of chronic urticaria, with and without angioedema, and there is light on the horizon suggesting success may come with various next-generation anti-IgE approaches.

Omalizumab Updosing in Chronic Spontaneous Urticaria: an Overview of Real-World Evidence

Chronic spontaneous urticaria (CSU) is defined as the spontaneous development of itchy hives and/or angioedema due to known or unknown causes that last for at least 6 weeks. At any given time, CSU is believed to affect 0.5–1% of the global population. Omalizumab (a recombinant, humanized anti-immunoglobulin-E antibody) is the only approved treatment for antihistamine refractory CSU. However, ~ 30% of patients remain symptomatic at licensed doses of omalizumab 150 mg and 300 mg, even after a treatment period of over 6 months. In the recent years, there have been several studies on updosing of the drug, suggesting that the individualized approach for urticaria treatment with omalizumab is useful. In this article, we provide an overview of these studies and the real-world data on omalizumab updosing as it became necessary to obtain complete CSU symptom control in a proportion of patients. Published observational studies (from June 2003 to October 2019) on the updosing of omalizumab in CSU were identified using PubMed and Ovid databases. Reports mainly show that updosing/dose adjustment evaluated with the assessment of disease activity (Urticaria Activity Score) and control (Urticaria Control Test) achieves better clinical response to omalizumab with a good safety profile in a pool of patients with CSU. These real-world data will provide an overview of updosing of omalizumab in CSU and aid in setting informed clinical practice treatment expectations.

In Chronic Spontaneous Urticaria, Comorbid Depression Linked to Higher Disease Activity, and Substance P Levels

Background: Patients with chronic spontaneous urticaria often exhibit psychiatric comorbidities including depression that contribute to the impairment of their quality of life. How CSU and depression are linked isn't well-understood. Substance P has been shown to be increased in patients with CSU and is held to contribute to the pathogenesis of depression. Methods: We measured disease activity in 30 CSU patients without depression and 30 CSU patients with depression by using the urticaria activity score. The severity of depression was assessed with the Beck Depression Inventory. We measured SP levels in these patients as well as in 30 healthy control subjects. In patients with comorbid depression, we correlated SP levels with CSU disease activity and the severity of depression. Results: In CSU patients, disease activity and the severity of depression were positively linked. UAS7 values were higher in CSU patients with comorbid depression as compared to those without (p < 0.05). SP levels were higher in CSU patients with depression than in those without (p < 0.001), but was similar in all CSU patients compared to healthy controls. SP levels weren't correlated with UAS7 values in CSU patients with depression, whereas they were weakly but significantly correlated with BDI scores (p < 0.05). Conclusion: Our results suggest that, in CSU patients with comorbid depression, CSU disease activity affects the severity of depression. CSU patients with high disease activity should be explored for comorbid depression.

Autoimmune Diseases Are Linked to Type IIb Autoimmune Chronic Spontaneous Urticaria

PURPOSE

Patients with chronic spontaneous urticaria (CSU) have an increased risk for comorbid autoimmune diseases. In this retrospective multicenter study of CSU patients, we evaluated clinical and laboratory features of CSU associated with a higher risk of comorbid autoimmune diseases.

METHODS

We analyzed records of CSU patients (n = 1,199) for a history or presence of autoimmune diseases. Patients were diagnosed with type IIb autoimmune CSU (aiCSU) if all 3 tests were positive: autologous serum skin test (ASST), basophil histamine release assay (BHRA) and/or basophil activation test (BAT), and IgG autoantibodies against FcεRIα/IgE detected by immunoassay.

RESULTS

Twenty-eight percent of CSU patients had at least 1 autoimmune disease. The most prevalent autoimmune diseases were Hashimoto's thyroiditis (HT) (≥ 21%) and vitiligo (2%). Two percent of CSU patients had ≥ 2 autoimmune diseases, most frequently HT plus vitiligo. Comorbid autoimmune diseases, in patients with CSU, were associated with female sex, a family history of autoimmune diseases, and higher rates of hypothyroidism and hyperthyroidism (P < 0.001). Presence of autoimmune diseases was linked to aiCSU (P = 0.02). The risks of having autoimmune diseases were 1.7, 2.9 and 3.3 times higher for CSU patients with a positive ASST, BHRA and BAT, respectively. In CSU patients, markers for autoimmune diseases, antinuclear antibodies and/or IgG anti-thyroid antibodies were associated with non-response to omalizumab treatment (P = 0.013).

CONCLUSIONS

In CSU, autoimmune diseases are common and linked to type IIb autoimmune CSU. Our results suggest that physicians assess and monitor all adult patients with CSU for signs and symptoms of common autoimmune diseases, especially HT and vitiligo.

Case Report: Off-Label Use of Omalizumab in a 6-Year-Old Boy With ASD Ameliorated Severe Allergic Rhinitis and Subsequently Improved Behavioral Symptoms

Children with ASD have elevated risk for developing allergic symptoms. The severity of allergic symptoms can exacerbate behavioral problems in children with ASD. Omalizumab, an anti-IgE antibody, has previously shown efficacy in treating allergic rhinitis and behavioral problems in a 12-year-old child with ASD. The present case report provides robust characterization of behavioral improvement in a 6-year-old child with ASD, allergic rhinitis, and autoimmune disorder. A 6-year-old boy with ASD and Hashimoto's disease presented to the clinic with severe allergic rhinitis, irritability, and language delay. After other treatments failed to improve symptoms, our patient was treated with omalizumab at 300 mg/month via subcutaneous injection for a total of 6 months. Marked improvement in allergic symptoms were observed at 2 months into treatment and were maintained through the treatment period. At the conclusion of the treatment period, results from multiple behavioral questionnaires, including the SRS-2, ABC, RBS-R, and PSQI, demonstrated substantial improvement in ASD-related behavioral symptoms. In this case, omalizumab markedly improved ASD-related and sleep behavior in a 6-year-old with ASD, allergic rhinitis, and autoimmune disorder. Future studies with larger patient populations are warranted to investigate the efficacy of omalizumab in patients with ASD and allergy symptoms.

IgE in the Pathogenesis of SLE: From Pathogenic Role to Therapeutic Target

Systemic lupus erythematosus (SLE) is a multifactorial chronic autoimmune disease, marked by the presence of autoantibodies to nuclear antigens belonging to different isotype classes. For several years, IgE antibodies have been incriminated in the development of allergic diseases and parasitic infections and different anti-IgE therapies have been developed to encounter the pathogenic role of IgE in these pathologies. Recently, multiple studies showed the presence of elevated total IgE levels and demonstrated a pathogenic role of autoreactive IgE in SLE. This review aims to summarize the findings incriminating IgE and autoreactive IgE in the pathophysiology of SLE, to describe their functional outcomes on their targeted cells as well as to discuss different IgE-related therapeutic modalities that emerged and that may be beneficial for SLE patient care.

Investigation of Serum Total IgE and Eosinophil Levels in Different Allergic Diseases Together with the Study of Their Correlations with Various Possible Allergens in Mosul City

Serum total IgE (tIgE) is frequently used in the diagnosis of allergic diseases in Mosul city and Iraq. However, neither normal nor elevated levels can exclude or confirm the diagnosis of these diseases. Here, we tried to evaluate the validity of tIgE in the diagnosis of allergic asthma(AS), allergic rhinitis(AR) and atopic dermatitis(AD) in a sample of Mosul population, to set up an optimum cut-off value for diagnosis of these diseases and to study its correlation with different parameters that might affect its level. 38 patients with AS, 27 with AR, 46 with AD and 45 healthy controls were included in this study. tIgE were determined by ELISA and compared between allergic diseases and controls. Blood eosinophilia was ascertained and correlated with tIgE levels. The geometric means of tIgE were 316.87 IU/ml (95% CI: 234.69 to 427.82) in AS, 262.07 IU/ml (95% CI:174.24 to 394.18) in AR and 270.48 IU/ml (95% CI:202.57 to 361.16) in AD compared to 16.90 IU/ml (95% CI:12.32 to 23.18) in healthy controls. tIgE in allergic diseases was significantly increased in comparison to healthy controls (P <.0001). Female gender influenced tIgE in AS, but not in AR or AD. tIgE predominated in younger age groups; however, no significant difference was found between younger and older groups. Optimum values for tIgE with best discriminative accuracy were 77 IU/ml for AS and 81 IU/ml for AR and AD. Eosinophils count appeared to be a useful adjunct, and correlate well with tIgE in the diagnosis of allergic diseases.

Omalizumab and adalimumab: a winning couple

Introduction: We report a case of a young female patient, previously affected by psoriatic arthritis, and treated with adalimumab, who developed a chronic spontaneous urticaria and started a concomitant therapy with omalizumab. Methods & results: A 50% reduction of the Dermatology Life Quality Index (from 7 at baseline to 4 in weeks 12 and 24) and a complete reset of the Urticaria Activity Score for 7 days (from 27 at baseline to 0 in weeks 12 and 24) were recorded. During all treatment with omalizumab, administering of adalimumab was continued. Due to complete control of urticaria symptoms, the patient stopped treatment with omalizumab after 24 weeks. Conclusion: The combination of adalimumab and omalizumab could offer a favorable efficacy and safety profile. The synergistic action of the two biological drugs in reducing systemic inflammation could be responsible for a shorter time to obtain clinical response.

Current and Potential Biologic Drugs for the Treatment of Chronic Urticaria

This article reviews biologic treatments that are currently applied for the treatment of severe chronic urticaria. Monoclonal anti-immunoglobulin E (omalizumab) is effective and safe in many patients, but accessibility and cost constitute barriers to its wider use. Questions on the optimal duration of the treatment and possible symptom recurrences after discontinuing the drug are still raised. A discussion is presented about several other biologics currently under investigation with potential to be incorporated in the near future in patients with severe chronic urticaria.

IgE-Mediated Immune Response and Antibody-Mediated Rejection

BACKGROUND AND OBJECTIVES

Active antibody-mediated rejection is the main cause of kidney transplant loss, sharing with SLE the alloimmune response and the systemic activation of the IFN-α pathway. IgE-mediated immune response plays a key role in the development of SLE nephritis and is associated with IFN-α secretion. The aim of our study was to investigate IgE-mediated immune response in antibody-mediated rejection.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

This was a cross-sectional study of 56 biopsy-proven antibody-mediated rejection study participants, 80 recipients with normal graft function/histology (control), 16 study participants with interstitial fibrosis/tubular atrophy, and six participants with SLE. We evaluated graft IgE deposition, tryptase (a mast cell marker), and CD203 (a specific marker of activated basophils) by immunofluorescence/confocal microscopy. In addition, we measured serum concentration of human myxovirus resistance protein 1, an IFN-α-induced protein, and anti-HLA IgE.

RESULTS

We observed a significantly higher IgE deposition in tubules and glomeruli in antibody-mediated rejection (1766±79 pixels) and SLE (1495±43 pixels) compared with interstitial fibrosis/tubular atrophy (582±122 pixels) and control (253±50 pixels). Patients with antibody-mediated rejection, but not control patients and patients with interstitial fibrosis/tubular atrophy, presented circulating anti-HLA IgE antibodies, although with a low mean fluorescence intensity. In addition, immunofluorescence revealed the presence of both mast cells and activated basophils in antibody-mediated rejection but not in control and interstitial fibrosis/tubular atrophy. The concentration of circulating basophils was significantly higher in antibody-mediated rejection compared with control and interstitial fibrosis/tubular atrophy. MxA serum levels were significantly higher in antibody-mediated rejection compared with control and correlated with the extent of IgE deposition.

CONCLUSIONS

Our data suggest that IgE deposition and the subsequent recruitment of basophils and mast cells within the kidney transplant might play a role in antibody-mediated rejection.

IgE Autoreactivity in Atopic Dermatitis: Paving the Road for Autoimmune Diseases?

Atopic dermatitis (AD) is a common skin disease affecting 20% of the population beginning usually before one year of age. It is associated with the emergence of allergen-specific IgE, but also with autoreactive IgE, whose function remain elusive. This review discusses current knowledge relevant to the mechanisms, which leads to the secretion of autoreactive IgE and to the potential function of these antibodies in AD. Multiple autoantigens have been described to elicit an IgE-dependent response in this context. This IgE autoimmunity starts in infancy and is associated with disease severity. Furthermore, the overall prevalence of autoreactive IgE to multiple auto-antigens is high in AD patients. IgE-antigen complexes can promote a facilitated antigen presentation, a skewing of the adaptive response toward type 2 immunity, and a chronic skin barrier dysfunction and inflammation in patients or AD models. In AD, skin barrier defects and the atopic immune environment facilitate allergen sensitization and the development of other IgE-mediated allergic diseases in a process called the atopic march. AD is also associated epidemiologically with several autoimmune diseases showing autoreactive IgE secretion. Thus, a potential outcome of IgE autoreactivity in AD could be the development of further autoimmune diseases.

Total Serum Immunoglobulin E Levels in Patients with Psoriasis

Introduction

Psoriasis is a common chronic skin disorder characterized by inflammation and abnormal epidermal proliferation. Its severity ranges from a chronic plaque psoriasis (CPP) to generalized psoriatic erythroderma (PE). The cause of psoriasis is unknown although most evidence supports the hypothesis that psoriasis is an immunologically mediated disease. The T-helper (Th) 1 and Th17 cells are responsible for the inflammation of psoriasis. Immunoglobulin E (IgE) is a class of immunoglobulin essential for the allergic response. There is some evidence that IgE may take a part in the pathogenesis of psoriasis.

Aim

The aim of the study was to compare serum levels of total IgE between patients with psoriasis and healthy subjects, and to assess the difference between localized form (CPP) and extensive form of disease (PE).

Methods

Seventy-five patients with psoriasis and 30 healthy subjects were enrolled in this study. Data on age, gender, personal and family history, clinical type and duration of disease were collected and analyzed. Serum levels of IgE were measured using nephelometric method.

Results

Serum levels of total IgE were significantly higher in patients than in controls (46.7% vs.. 10%; p<0.05). Statistical difference of IgE concentration was also observed between CPP and PE. Comparison between patients and controls with regard to the median of the serum level of total IgE levels showed a statistically highly significant elevation in patients (425 IU/ml) compared with controls (54.5 IU/ml) (p<0,05). A higher total IgE concentration was observed in the group of patients with a longer period of skin changes. No relation was found between the serum level of IgE and family history of psoriasis, age or sex (p>0.05).

Conclusions

This study supports the evidence that elevation of total serum IgE is associated with psoriasis. The exact role of serum IgE in psoriasis should be additionally investigated in future studies.

IgE autoantibodies and autoreactive T cells and their role in children and adults with atopic dermatitis

The pathophysiology of atopic dermatitis (AD) is highly complex and understanding of disease endotypes may improve disease management. Immunoglobulins E (IgE) against human skin epitopes (IgE autoantibodies) are thought to play a role in disease progression and prolongation. These antibodies have been described in patients with severe and chronic AD, suggesting a progression from allergic inflammation to severe autoimmune processes against the skin. This review provides a summary of the current knowledge and gaps on IgE autoreactivity and self-reactive T cells in children and adults with AD based on a systematic search. Currently, the clinical relevance and the pathomechanism of IgE autoantibodies in AD needs to be further investigated. Additionally, it is unknown whether the presence of IgE autoantibodies in patients with AD is an epiphenomenon or a disease endotype. However, increased knowledge on the clinical relevance and the pathophysiologic role of IgE autoantibodies and self-reactive T cells in AD can have consequences for diagnosis and treatment. Responses to the current available treatments can be used for better understanding of the pathways and may shed new lights on the treatment options for patients with AD and autoreactivity against skin epitopes. To conclude, IgE autoantibodies and self-reactive T cells can contribute to the pathophysiology of AD based on the body of evidence in literature. However, many questions remain open. Future studies on autoreactivity in AD should especially focus on the clinical relevance, the contribution to the disease progression and chronicity on cellular level, the onset and therapeutic strategies.

Vipera snakebite in Europe: a systematic review of a neglected disease

In 2009, snakebites were included in the list of the World Health Organization (WHO) neglected diseases. Dermatological literature lacks current and up-to-date articles about snakebites and their management, despite the fact that dermatologists, especially from rural hospitals, can be called into the emergency room to consult the management of suspected snakebites. In this systematic review, we highlighted the main clinical and laboratory aspects of snakebites from Vipera spp. in Europe, by reviewing 3574 studies initially retrieved from PubMed, Embase and Cochrane CENTRAL databases. Of these, 78 were finally included in the systematic review. We found that the most involved taxon was V. berus in 63.3% and the most involved anatomic site of the bite was the upper limbs 53.1% with fang marks reported in 90.5%. The mean age of the patients was 32.9 years, and bites were slightly more common among males (58.2%). A wound washing was performed in 86.9% of cases before the hospitalization. The most frequently reported grade of envenomation was G2 (42.2%). In addition to local dermatological symptoms (extended erythema, oedema, cutaneous necrosis, hives, purpura, petechiae, acute compartment syndrome), numerous systemic symptoms have also been reported, including fatigue (14.4%), pain (75.3%), fever (49.2%), direct anaphylactoid reaction (5.3%), anxiety (60.8%), cranial nerve neurotoxicity (14.8%), dysesthesia/paraesthesia (7.9%), vomiting (33.7%), abdominal pain (23.3%), diarrhoea (15.4%), dyspnoea (6.3%), proteinuria (10.6%) and haematuria (9.3%). Secondary infections were present in 3.5% and disseminated intravascular coagulation in 3.1% of cases, and fasciotomy was performed in 4.2% cases, while an amputation in 6.9%. Only 0.9% of patients died. Antivenom was administered in 3053 cases. In conclusion, there is a pressing need for robust multi-centre randomized control trials, standardized protocol for snakebite management and antivenom administration across Europe and a National snakebite register for each European country.

AllergoOncology: ultra-low IgE, a potential novel biomarker in cancer-a Position Paper of the European Academy of Allergy and Clinical Immunology (EAACI)

Elevated serum IgE levels are associated with allergic disorders, parasitosis and specific immunologic abnormalities. In addition, epidemiological and mechanistic evidence indicates an association between IgE-mediated immune surveillance and protection from tumour growth. Intriguingly, recent studies reveal a correlation between IgE deficiency and increased malignancy risk. This is the first review discussing IgE levels and links to pathological conditions, with special focus on the potential clinical significance of ultra-low serum IgE levels and risk of malignancy. In this Position Paper we discuss: (a) the utility of measuring total IgE levels in the management of allergies, parasitosis, and immunodeficiencies, (b) factors that may influence serum IgE levels, (c) IgE as a marker of different disorders, and d) the relationship between ultra-low IgE levels and malignancy susceptibility. While elevated serum IgE is generally associated with allergic/atopic conditions, very low or absent IgE may hamper anti-tumour surveillance, indicating the importance of a balanced IgE-mediated immune function. Ultra-low IgE may prove to be an unexpected biomarker for cancer risk. Nevertheless, given the early stage of investigations conducted mostly in patients with diseases that influence IgE levels, in-depth mechanistic studies and stratification of malignancy risk based on associated demographic, immunological and clinical co-factors are warranted.

Ligelizumab for the treatment of chronic spontaneous urticaria

INTRODUCTION

Due to daily hives with itch, sleeplessness, and unforeseen development of angioedema, chronic spontaneous urticaria significantly impairs quality of life, often for years. Its management is challenging. In most cases, H1-antihistamines are not effective. Although the disease is not characterized by specific IgE antibodies against allergens, the last decade demonstrated that neutralizing IgE by using the monoclonal anti-IgE antibody Omalizumab is safe and effective. Nevertheless, symptoms are not controlled by Omalizumab in approximately one-fourth of patients.

AREAS COVERED

This review is focused on Ligelizumab (QGE031), a next-generation non-triggering fully human monoclonal antibody, with higher affinity to IgE compared to Omalizumab.

EXPERT OPINION

In chronic spontaneous urticaria, subcutaneous Ligelizumab once per month for five months has shown a clear dose-response relationship with respect to symptoms. Superiority over Omalizumab was noted whereas the safety profile was similar. Most common side effects were injection site reactions. In the near future, results from phase 3 trials, two of them including more than 1000 patients each, are awaited. Having a higher affinity to IgE and being more effective than Omalizumab, Ligelizumab has the potential to free chronic urticaria patients from year-long daily annoying symptoms that did not respond to standard therapy as recommended by current guidelines.

Regulation of B-cell function by NF-kappaB c-Rel in health and disease

B cells mediate humoral immune response and contribute to the regulation of cellular immune response. Members of the Nuclear Factor kappaB (NF-κB) family of transcription factors play a major role in regulating B-cell functions. NF-κB subunit c-Rel is predominantly expressed in lymphocytes, and in B cells, it is required for survival, proliferation, and antibody production. Dysregulation of c-Rel expression and activation alters B-cell homeostasis and is associated with B-cell lymphomas and autoimmune pathologies. Based on its essential roles, c-Rel may serve as a potential prognostic and therapeutic target. This review summarizes the current understanding of the multifaceted role of c-Rel in B cells and B-cell diseases.

Prevalence of allergen sensitization among 1,091 patients with urticaria

The etiology of urticaria is heterogeneous and allergic responses may be involved in it. The aim of the present study was to investigate the prevalence and distribution of sensitivity to inhaled and food allergens among patients with urticaria in Henan province (China). The levels of specific immunoglobulin E (sIgE) were detected using the AllergyScreen test and a total of 524/1,091 cases (48.0%) tested positive for sIgE to at least one of the 19 allergens. The most common inhaled allergens the urticaria patients were sensitive to were D. pteronyssinus (34.5%), cockroach (12.5%) and tree pollen mix (11.1%), while the food allergens with the highest rate of allergic reactions were cashew nut (8.1%), shrimp (6.8%) and crab (6.4%). The positive rates for D. pteronyssinus, dog hair, cockroach, mold mix, tree pollen mix and shrimp in the chronic urticaria group were higher than those in the acute urticaria group (P<0.05). Furthermore, positive rates for the majority of allergens were higher in males than in females and were significantly different between age groups (P<0.05). The results of the present study provided information on the characteristics of allergen sensitization of patients with urticaria and may facilitate the prevention, diagnosis and management of urticaria in Henan province.

Identification of antigenic epitopes of thyroperoxidase, thyroglobulin and interleukin-24. Exploration of cross-reactivity with environmental allergens and possible role in urticaria and hypothyroidism

BACKGROUND

Human proteins such as interleukin-24 (IL24), thyroperoxidase (TPO) and thyroglobulin (Tg) are targets of IgE or IgG autoantibodies. Why these proteins are recognized by autoantibodies in some patients with chronic spontaneous urticaria (CSU) or hypothyroidism is unknown.

OBJECTIVE

Through in silico analysis, identify antigen patches of TPO, Tg and IL24 and compare the sequences of these human proteins with some prevalent allergens.

METHODS

The amino acids sequences of IL24, thyroperoxidase and thyroglobulin were compared between them and with 22 environmental allergens. Phylogenetic studies and multiple pairing were carried out to explore the degree of protein identity and cover. The proteins without 3D structure reported in the database, were modeled by homology with "Swiss Modeller" and compared through PYMOL. Residues conserved and accessible to the solvent (rASA> 0.25) were located in the 3D model to identify possible areas of cross-reactivity and antigen binding.

RESULTS

We build a 3D model of the TPO and thyroglobulin protein base on proteins closely related. Five epitopes for TPO, six for IL24 and six for thyroglobulin were predicted. The amino acid sequences of allergens from different sources (Dermatophagoides pteronyssinus, Blomia tropicalis, Betula verrucosa, Cynodon dactylon, Aspergillus fumigatus, Canis domesticus, Felis domesticus) were compared with human TPO, Tg and IL24. The cover and alignments between allergens and human proteins were low.

CONCLUSION

We identify possible linear and conformational epitopes of TPO, Tg and IL24 that could be the target of IgE or IgG binding in patients with urticaria or hypothyroidism; These epitopes do not appear to be present among common environmental allergens, suggesting that autoreactivity to these human proteins are not by cross-reactivity.

Clinical Characterization of Patients with Chronic Spontaneous Urticaria according to Anti-TPO IgE Levels

Background

Chronic spontaneous urticaria (CSU) is a heterogeneous disease with some frequent comorbidities like autoimmune diseases, drug reactions, and inducible urticaria. IgE antibodies against thyroid peroxidase (anti-TPO IgE) could be associated with some of these clinical characteristics.

Objective

To explore the clinical characteristics of CSU patients, according to the presence of anti-TPO IgE in serum.

Methods

Anti-TPO IgE levels were measured during the clinical control period (Urticaria Activity Score, 0 point) and exacerbation period (≥3 points) in 100 CSU patients. Patients with self-reported exacerbation of skin involvement by foods, nonsteroidal anti-inflammatory drugs (NSAIDs), and physical triggers underwent controlled challenge tests.

Results

We identified 2 groups of patients: (1) patients with anti-TPO IgE during the clinical control period or during an exacerbation, who had a higher frequency of atopy, asthma, and positive challenge test results with NSAIDs and (2) patients without anti-TPO IgE during any period, who had a higher frequency of positive challenge test results for inducible urticaria. Among the first group (anti-TPO IgE at any point), we identified 3 subgroups: patients with anti-TPO IgE during the clinical control period (n = 12); patients with anti-TPO IgE during the clinical control period and significantly increased levels during an urticaria exacerbation (n = 18); and patients with anti-TPO IgE only during an exacerbation (n = 13). None of the patients with self-reported food reactions had a positive challenge test result.

Conclusion

Anti-TPO IgE is a useful biomarker for differentiating between clinical phenotypes of patients with CSU. Elevation of anti-TPO IgE during exacerbation periods supports an association between this autoantibody and the pathogenesis of urticaria.

H. Grattan C, Jakob T, Konstantinou GN, Raap U, Skov PS, Staubach P, Kromminga A, Zhang K, Bindslev‐Jensen C, Daschner A, Kinaciyan T, Knol EF, Makris M, Marrouche N, Schmid‐Grendelmeier P, Sussman G, Toubi E, Church MK, Maurer M. Biomarkers and clinical characteristics of autoimmune chronic spontaneous urticaria: Results of the PURIST Study

BACKGROUND

Autoimmune chronic spontaneous urticaria (aiCSU) is an important subtype of chronic spontaneous urticaria (CSU) in which functional IgG autoantibodies to IgE or its high-affinity receptor (FcεRI) induces mast cell degranulation and subsequent symptom development. However, it has not been tightly characterized. This study aimed to better define the clinical and immunological features and to explore potential biomarkers of aiCSU.

METHODS

This was a multinational, multicenter study of 182 CSU patients. The clinical features studied included: urticaria activity and impact (UAS7 and quality of life); autologous serum skin test (ASST); IgG anti-FcεRI and IgG anti-IgE; IgG-anti-thyroperoxidase (IgG anti-TPO); total serum IgE; and basophil reactivity (BASO) using the basophil activation test (BAT) and basophil histamine release assay (BHRA).

RESULTS

Of the 182 patients, 107 (59%) were ASST+, 46 (25%) were BASO+, and 105 (58%) were IgG anti-FcεRI+/IgE+. Fifteen patients (8%) fulfilled all three criteria of aiCSU. aiCSU patients appeared more severe (UAS7 21 vs 9 P < 0.016) but showed no other clinical or demographic differences from non-aiCSU patients. aiCSU patients also had markedly lower total IgE levels (P < 0.0001) and higher IgG anti-TPO levels (P < 0.001). Of biomarkers, positive BAT and BHRA tests were 69% and 88% predictive of aiCSU, respectively.

CONCLUSIONS

aiCSU is a relatively small but immunologically distinct subtype of CSU that cannot be identified by routine clinical parameters. Inclusion of BHRA or BAT in the diagnostic workup of CSU patients may aid identification of aiCSU patients, who may have a different prognosis and benefit from specific management.

Autoimmunity (or Not) in Atopic Dermatitis

Atopic dermatitis (AD), one of the most frequent inflammatory skin diseases worldwide, is believed to result from a disturbed skin barrier as well as aberrant immune reactions against per se harmless allergens. Starting mostly during childhood with a chronic, remitting relapsing course, the disease can persist into adulthood in about one fifth of patients. Immune reactions to self-proteins have been observed in AD patients already in the beginning of the Twentieth century, when human cellular extracts were shown to provoke skin lesions. However, the term “autoimmunity” has never been claimed, since AD is first and foremost an atopic disease. In contrast, this IgE-hallmarked autoreactivity was termed “autoallergy” and is ongoing discussed regarding its impact on the disease. Since severely affected patients tend to develop IgE-hypersensitivity reactions to numerous environmental allergens, the impact of immune responses to self-proteins is difficult to determine. On the other hand: any autoreactivity, irrespective of the magnitude, implicates the potential of driving the chronification of the disease while shaping the immune response. This review article revisits the observations made on autoallergy from an actual point of view and tries to approach the question whether these still point to a contribution to the disease.

Spatial and functional heterogeneity of follicular helper T cells in autoimmunity

Follicular helper T cells provide signals that promote B cell development, proliferation, and production of affinity matured and appropriately isotype switched antibodies. In addition to their classical locations within B cell follicles and germinal centers therein, B cell helper T cells are also found in extrafollicular spaces - either in secondary lymphoid or non-lymphoid tissues. Both follicular and extrafollicular T helper cells drive autoantibody-mediated autoimmunity. Interfering with B cell help provided by T cells can ameliorate autoimmune disease in animal models and human patients. The next frontier in Tfh cell biology will be identification of Tfh cell-specific pathogenic changes in autoimmunity and exploiting them for therapeutic purposes.

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.

Pruritus in Autoimmune and Inflammatory Dermatoses

Pruritus in autoimmune and inflammatory dermatoses is a common symptom that can be severe and affect the quality of life of patients. In some diseases, pruritus is related to disorders activity and severity or may occur independent of the disease. Despite the high prevalence, the symptom is still underrated and there are only a few trials investigating the efficacy of drugs for disease-specific pruritus. In this review, the characteristics and possible pathomechanisms of pruritus in various dermatoses like autoimmune bullous diseases, connective tissue diseases as well as autoimmune-associated dermatoses (atopic dermatitis, psoriasis vulgaris) is illustrated. Additionally, studies analyzing the antipruritic treatment are discussed. Summarizing, the prevalence of pruritus in these diseases demonstrates the importance for symptom recognition and the need for an efficient antipruritic therapy.

A new look at IgE beyond allergies

Immunoglobulin E (IgE), though constitutively present at low levels, is most commonly studied in atopic disease where it plays a vital role in mast cell degranulation and in initiating a T helper 2 (Th2) response. With the advent of better detection assays, however, researchers are discovering the importance of IgE in actively contributing to many disease states and pathologies. This review will discuss the latest findings in IgE beyond its role in allergies and recently discovered roles for IgE in its cell-bound form on FcεRI-expressing effector cells like monocytes and dendritic cells. In terms of parasites, we will discuss helminth-induced IgE that appears to protect the worms from immune recognition and a tick-borne illness that elicits an IgE response against red meat. Next, we describe recent findings of how auto-reactive IgE can contribute to the progression of lupus and induce organ damage. Finally, we summarize the emerging roles of IgE in tumor surveillance and antibody-dependent cytotoxicity. We additionally discuss recent or ongoing clinical trials that either target harmful IgE or use the unique characteristics of the isotype.

Autoimmune Theories of Chronic Spontaneous Urticaria

Urticaria (hives) is a highly prevalent skin disorder that can occur with or without associated angioedema. Chronic spontaneous urticaria (CSU) is a condition which persists for more than 6 weeks in duration and occurs in the absence of an identifiable provoking factor. CSU results from pathogenic activation of mast cells and basophils, which gives rise to the release of proinflammatory mediators that support the generation of urticaria. Several theories have been put forth regarding the pathogenesis of CSU with much evidence pointing toward a potential autoimmune etiology in up to 50% of patients with this condition. In this review, we highlight the evidence surrounding the autoimmune pathogenesis of chronic urticaria including recent data which suggests that CSU may involve contributions from both immunoglobin G (IgG)-specific and immunoglobulin E (IgE)-specific autoantibodies against a vast array of antigens that can span beyond those found on the surface of mast cells and basophils.