Autoimmune chronic spontaneous urticaria

Paeoniflorin as a potential agent for urticaria treatment: Suppressing mast cell degranulation through HMGB1/TLR4/NF-κB signaling inhibition

INTRODUCTION

Paeoniflorin (PF) has strong immunomodulatory effects and has been widely used in the treatment of many diseases, but its mechanism of action in urticaria is not clear. The aim of this experiment was to investigate the role and mechanism of paeoniflorin in improving mast cell degranulation in urticaria.

METHODS

The mouse model of urticaria was replicated by ovalbumin+ aluminum hydroxide method, and the mast cell degranulation model was induced by anti-DNP IgE+ Dinitrophenyl- Bovine Serum Albumin (DNP-BSA), and the mice and cells were intervened by different doses of PF. The histopathological changes of the dorsal skin were observed using hematoxylin-eosin (HE) staining, the infiltration of mast cells was observed by Toluidine blue staining, the expression of mast cell tryptase (MCT) was examined by Immunohistochemical staining, the cell viability was detected by CCK8 assay, and Rhod-2/AM flow cytometry assay to determine calcium ion content, enzyme-linked immunosorbent assay (ELISA) detected mast cell degranulation-associated factors, and Western blot analyzed HMGB1/TLR4/NF-κB signaling factors.

RESULTS

PF reduced the number of scratches in mice, ameliorated histopathological damage in dorsal skin, decreased mast cell degranulation rate, reduced the levels of Ca2 +, MCT, β-HEX, HIS, MCP-1, TNF-α, and IL-13, and inhibited the expression of HMGB1, TLR4, MyD88, NF-κB p65 (Nucleus), and p-IκBα. Moreover, Rec-HMGB1 reversed the effect of PF.

CONCLUSION

PF mitigates urticarial mast cell degranulation through the inhibition of the HMGB1/TLR4/NF-κB signaling pathway, suggesting its potential as a therapeutic agent for the treatment of urticaria.

Efficacy and Safety of Ligelizumab in Chronic Spontaneous Urticaria: A Systematic Review and Meta-analysis of Randomized Controlled Trials

BACKGROUND AND OBJECTIVE: This meta-analysis aims to evaluate ligelizumab's efficacy and safety for chronic spontaneous urticaria (CSU) treatment by analyzing recent clinical trials and comparing it with placebo and omalizumab.

METHODS

PubMed, Embase, and Cochrane were searched up to October 2024. Eligible studies were randomized controlled trials (RCTs) comparing ligelizumab with placebo or omalizumab, reporting relevant outcomes. Nonrandomized studies, or those without control groups, were excluded. Risk of bias was assessed using the Cochrane RoB-2 tool, and the Grading of Recommendation, Assessment, Development, and Evaluations approach rated evidence certainty. Statistical analysis used R software (v.4.4.2), assessing heterogeneity by Cochran Q and I2 statistics.

RESULTS

Four RCTs with 2488 patients were included. Ligelizumab (< 72 mg) significantly improved itch severity score over 7 days (ISS7) [risk ratio (RR) 5.07; 95% confidence interval (CI) 3.12-8.24; prediction interval (PI) 2.31-11.15; P < 0.01; I2 = 0%], urticaria activity score over 7 days (UAS7) (RR 4.61; 95% CI 1.84-11.59; PI 0.34-62.49; P < 0.01; I2 = 55%), and overall urticaria activity (RR 4.26; 95% CI 2.63-6.92; PI 0.18-98.29; P < 0.01; I2 = 0%) versus placebo. The > 72 mg dose showed greater improvements in ISS7 (RR 5.12; 95% CI 2.72-9.64; PI 1.14-22.96; P < 0.01; I2 = 45%), UAS7 (RR 5.35; 95% CI 3.04-9.40; PI 1.78-16.08; P < 0.01; I2 = 31%), and overall activity (RR 4.34; 95% CI 2.67-7.04; PI 0.19-99.80; P < 0.01; I2 = 0%). Compared with ligelizumab (> 72 mg), omalizumab had fewer injection site reactions (RR 3.04; 95% CI 1.95-4.73; PI 0.17-53.81; P < 0.01; I2 = 0%) and erythema (RR 5.05; 95% CI 1.33-19.13; PI 0.08-312.57; P = 0.02; I2 = 17%). Moderate certainty evidence indicated that ≤ 72 mg probably improved ISS7, overall urticaria activity, and UAS7. For > 72 mg, improvements in overall urticaria activity were seen, but ISS7 and UAS7 were classified as low quality of evidence.

DISCUSSION

Ligelizumab significantly improves CSU symptoms compared with placebo, reducing disease severity, itching, and hives, with similar safety to omalizumab. Ligelizumab's higher affinity for immunoglobulin E (IgE) may provide better symptom control. Limitations include a small number of studies, short follow-up periods, and patient variability.

PROTOCOL REGISTRATION

International Prospective Register of Systematic Reviews (PROSPERO), CRD42024593072.

Global productivity, international collaborations, and research trends in chronic spontaneous urticaria: A bibliometric overview

Background

The treatment of chronic spontaneous urticaria (CSU) remains a challenge despite novel therapies such as omalizumab. With growing international interest in research on CSU, a comprehensive review of the global productivity, collaborations, and trending topics in CSU research may help inform future directions in patient management.

Objectives

This study aims to outline the trends in CSU research by using bibliometric analysis, focusing specifically on global productivity, collaborative efforts, and emerging research topics spanning from 1977 to 2023.

Methods

Publications related to CSU, including original articles, reviews, and letters, were sourced from the Web of Science Core Collection, and statistical analyses were performed using the Bibliometrix package in R and IBM SPSS Statistics.

Results

A total of 2940 publications from 77 countries were analyzed. CSU research activity has increased exponentially since 2010, with more than half of the publications (50.2% [1477 of 2940]) published since 2016. These publications appeared in allergy, immunology, and dermatology journals led predominantly by European, Asian, and American researchers. International collaborations rose from 11.3% to 22.2%. Shifts in research focus, such as a shift in treatments from antihistamines to omalizumab, and growing emphasis on quality of life were noted.

Conclusion

This study revealed a dynamic and increasingly collaborative CSU research landscape, emphasizing the need for continuous global partnerships to enhance treatment outcomes and improve patients' quality of life. Challenges regarding access to advanced therapies persist, highlighting the importance of expanding international collaborations and inclusive research practices.

Biological and target synthetic treatments for chronic spontaneous urticaria: A systematic review and network meta-analysis

BACKGROUND

Most biological and synthetic target-specific drugs for antihistamine-refractory chronic spontaneous urticaria (CSU) have not been compared head-to-head. This systematic review and network meta-analysis evaluated their relative efficacy and safety.

METHODS

Searches were conducted on PubMed, Embase, Web of Science and Cochrane library databases to March 25, 2024 for randomized trials. A random-effects model was used to calculate the network estimates reported as mean differences (MD) and odds ratios (OR) with corresponding 95% CIs. Main outcomes included the weekly urticaria activity score (UAS7), adverse events (AEs) and serious adverse events (SAEs).

RESULTS

23 randomized clinical trials with 6933 participants that compared 26 different interventions or dosages and placebos were included. Omalizumab 300 mg [MD -10.07, 95% CI (-11.35; -8.82)] continues to demonstrate superior efficacy compared with placebo. Remibrutinib, at doses of 35 mg once daily [MD -7.80, 95% CI (-12.76; -2.51)], 25 mg twice daily [MD -7.69, 95% CI (-9.85; -5.76)], and 10 mg twice daily [MD -7.61, 95% CI (-12.59; -2.47)], had the best overall performance for efficacy and safety. Dupilumab, fenebrutinib, and rilzabrutinib also showed greater efficacy than placebo. The results were similar for the proportion of patients who achieved UAS7 ≤ 6 or UAS7 = 0. No significant differences were found among all treatment comparisons for AEs and SAEs.

CONCLUSION

The findings of this study indicate that the biological agent omalizumab 300 mg and the oral small molecule remibrutinib at doses of 35 mg, 25 mg, or 10 mg are recommended for patients with antihistamine-refractory CSU.

TRIAL REGISTRATION

PROSPERO: CRD42024516289.

Immunological Avalanches in Renal Immune Diseases

The complex nature of immune system behavior in both autoimmune diseases and transplant rejection can be understood through the lens of avalanche dynamics in critical-point systems. This paper introduces the concept of the "immunological avalanche" as a framework for understanding unpredictable patterns of immune activity in both contexts. Just as avalanches represent sudden releases of accumulated potential energy, immune responses exhibit periods of apparent stability followed by explosive flares triggered by seemingly minor stimuli. The model presented here draws parallels between immune system behavior and other complex systems such as earthquakes, forest fires, and neuronal activity, where localized events can propagate into large-scale disruptions. In autoimmune conditions like systemic lupus erythematosus (SLE), which affects multiple organ systems including the kidneys in approximately 50% of patients, these dynamics manifest as alternating periods of remission and flares. Similarly, in transplant recipients, the immune system exhibits metastable behavior under constant allograft stimulation. This critical-point dynamics framework is characterized by threshold-dependent activation, positive feedback loops, and dynamic non-linearity. In autoimmune diseases, triggers such as UV light exposure, infections, or stress can initiate cascading immune responses. In transplant patients, longitudinal analysis reveals how monitoring oscillatory patterns in blood parameters and biological age markers can predict rejection risk. In a preliminary study on kidney transplant, all measured variables showed temporal instability. Proteinuria exhibited precise log-log linearity in power law analysis, confirming near-critical-point system behavior. Two distinct dynamic patterns emerged: large oscillations in eGFR, proteinuria, or biological age predicted declining function, while small oscillations indicated stability. During avalanche events, biological age increased dramatically, with partial reversal leaving persistent elevation after acute episodes. Understanding these dynamics has important implications for therapeutic approaches in both contexts. Key findings suggest that monitoring parameter oscillations, rather than absolute values, better indicates system instability and potential avalanche events. Additionally, biological age calculations provide valuable prognostic information, while proteinuria measurements offer efficient sampling for system dynamics assessment. This conceptual model provides a unifying framework for understanding the pathogenesis of both autoimmune and transplant-related immune responses, potentially leading to new perspectives in disease management and rejection prediction.

Clinical phenotypes and biomarkers in chronic urticaria

The medical field faces considerable challenges in treating chronic urticaria (CU), which includes both chronic spontaneous urticaria (CSU) and chronic inducible urticaria, owing to its varied nature. The complexity of this condition stems from multiple factors: varying disease mechanisms, different ways in which symptoms manifest, and inconsistent treatment outcomes. Although both forms of CU display hives that persist beyond six weeks, they have distinct causes and progression patterns. This study examines CSU specifically, exploring its various manifestations and associated biological indicators. Currently, there is a pressing need to identify reliable, accessible biomarkers for CSU to enhance diagnosis and develop targeted treatments. Better insights into how specific disease patterns are related to biological markers would significantly improve our understanding of CSU development and enhance patient treatment approaches.

Managing Chronic Urticaria in Children: An Update

PURPOSE OF REVIEW

To provide an update and new insights into the management of pediatric patients with chronic urticaria.

RECENT FINDINGS

Chronic urticaria in children may be more prevalent than previously thought, with a high resolution rate within two years. Patient-reported outcome measures (PROMs) are effective tools for assessing disease severity and control in pediatric populations. Children with chronic urticaria generally respond better to H1-antihistamines compared to adults. For patients refractory to antihistamines, omalizumab has shown excellent efficacy. Additionally, dupilumab has emerged as a potential treatment option, as it has been approved for chronic spontaneous urticaria in some countries. Managing chronic urticaria in children remains a diagnostic and therapeutic challenge. However, advancements in understanding disease mechanisms, the validation of tools to assess disease activity and control, the development of reliable biomarkers, and the availability of novel therapies offer significant promise. These developments will enable more effective treatment and improved outcomes for pediatric patients.

Mortality in adult patients with chronic spontaneous urticaria: A real-world cohort study

BACKGROUND

Chronic spontaneous urticaria (CSU), a common and debilitating disease, is widely held not to be life limiting, but the mortality of CSU has not been investigated.

OBJECTIVE

We sought to assess all-cause mortality in patients with CSU, risk for comorbidities that are leading causes of death, and impact of guideline-recommended urticaria treatments on mortality rates.

METHODS

This was a retrospective population-based cohort study of electronic health records of 272,190 adult patients with CSU and 12,728,913 controls without urticaria from the US collaborative network TriNetX.

RESULTS

The study included 264,680 propensity score-matched patients with CSU (mean [SD] age = 47.5 [19.8] years; 71.5% female) and a corresponding number of controls without urticaria. Patients with CSU had higher 3-month (hazard ratio [HR] 2.10, 95% CI 1.97-2.22), 1-year (HR 1.77, 95% CI 1.71-1.83), and 5-year (HR 1.69, 95% CI 1.65-1.73) all-cause mortality (all P < .0001). Compared with controls, patients with CSU exhibited higher risk and rates of the leading causes of death in the United States, including suicidal ideations/suicide attempts (HR 3.14, 95% CI 3.00-3.28) and malignant neoplasms (HR 2.09, 95% CI 2.02-2.16). The risk of mortality appeared to be more pronounced in White and younger patients with CSU. All-cause mortality rates at 5 years were significantly lower in patients treated with second-generation H1 antihistamines versus untreated patients (1.0% vs 2.3%; HR 1.84, P < .0001) and omalizumab-treated patients versus antihistamine-treated patients (0.7% vs 2.6%; HR 3.99, P = .0003).

CONCLUSIONS

CSU is associated with increased mortality likely due to comorbidities, especially suicide, and effective CSU treatment may reduce mortality. These findings should be investigated in additional studies and in other populations.

Endotypes, phenotypes, and biomarkers in chronic spontaneous urticaria: Evolving toward personalized medicine

Chronic spontaneous urticaria (CSU) is an inflammatory disorder that manifests with hives, angioedema, or both and lasts more than or equal to 6 weeks. Although certain elements of CSU pathogenesis are well defined, others remain unclear. We discuss our current understanding of the underlying CSU endotypes, distinct clinical phenotypes, and predictive biomarkers. It is increasingly recognized that CSU comprises a spectrum of different underlying pathogenic mechanisms and distinct clinical presentations. Broadly, 2 endotypes that drive CSU pathogenesis have been identified, namely type I (autoallergic) and type IIb (autoimmune). However, a subpopulation shows evidence of both types, and some patients show evidence of neither. Multiple identified biomarkers have been associated with these endotypes or with disease features, such as CSU severity and duration. There is a lack of connectivity among the identified biomarkers, genetic risk loci, phenotypes, and corresponding endotypes, and each of these is frequently considered independently of the others. These identifiable features also have been associated with response, or lack thereof, to available therapies. Future investigations should optimize the endotyping of CSU using point-of-care, noninvasive, accessible biomarkers and assess the differences in response to therapy. With multiple treatments in late-stage development, establishing clearly defined CSU endotypes will facilitate future treatment decision-making and tailored treatment approaches and will inform optimal trial design.

Update on the Treatment of Chronic Spontaneous Urticaria

Chronic spontaneous urticaria (CSU) is a mast cell-mediated skin disease that presents with wheals, angioedema, or both for more than 6 weeks. Less than 10% of patients have complete control of their CSU (the main goal of CSU treatment) with second generation H1-antihistamines, the first-line treatment. About 70% of patients with antihistamine-refractory CSU do not reach complete control with omalizumab, the second-line treatment. Novel therapies are especially needed for patients with mast cell-activating immunoglobulin (Ig)G autoantibodies (autoimmune CSU) associated with nonresponse or late response to omalizumab. Furthermore, there is a lack of disease-modifying treatments that induce long-term CSU remission after drug withdrawal. Several emerging treatments can address these unmet needs including Bruton tyrosine kinase inhibitors, e.g., remibrutinib and rilzabrutinib; anti-KIT monoclonal antibodies, e.g., barzolvolimab; and anti-cytokine therapies, e.g., dupilumab. In clinical trials, 30-31%, 28-32%, and 38-51% of patients with CSU showed complete response to treatment with dupilumab (phase 3, week 24), remibrutinib (phase 3, week 24), and barzolvolimab (phase 2, week 12), respectively. The most common adverse events were injection site reactions for dupilumab (12%), respiratory tract infections (11%), headache (6%), and petechiae (4%) for remibrutinib and changes in hair color (14%), neutropenia / decreased neutrophil count (9%) and skin hypopigmentation (1%) for barzolvolimab. This review provides an update on the current state of development of treatments for CSU.

The Role of Coagulation/Fibrinolysis Biomarkers in Pathophysiology, Disease Severity, and Treatment Response in Patients with Urticaria: A Scoping Review

The pathology of urticaria is complex. Recently, researchers have widely focused on the role that the coagulation/fibrinolysis system plays in the pathology of urticaria. The potential of coagulation/fibrinolysis biomarkers as disease severity or treatment response biomarkers remains uncertain, lacking comprehensive analysis in previous studies. Hence, we performed a scoping review to thoroughly analyze coagulation/fibrinolysis biomarkers that may predict disease progression and treatment response of urticaria. Data from 71 studies showed that chronic spontaneous urticaria (CSU) was the most-studied subtype (39 articles), with D-dimers being the most researched marker (56 articles). Twenty-one biomarkers were investigated, and ten biomarkers were significantly correlated with disease severity. Specifically, D-dimers (26 articles) and prothrombin fragment 1 + 2 (F1+2) (12 articles) plasma levels increased with exacerbation and decreased with remission. Biomarkers such as D-dimer also correlated significantly with inflammatory cytokines and complement, suggesting interactions among coagulation, immunity, and inflammation in the pathology of urticaria. While these biomarkers may predict treatment response, more evidence is needed. Additionally, anticoagulants such as warfarin, heparin sodium and tranexamic acid have been proved effective for urticaria. This review emphasizes that some coagulation/fibrinolysis biomarkers (such as D-dimer and F1+2) may be not only indicators of disease status but also potential predictors of treatment response. It aims to assist researchers and practitioners in gaining a better understanding of the close relationships among coagulation/fibrinolysis biomarkers, the condition of urticaria (especially chronic urticaria, CU), and its prognosis. It also provides new directions for future research on exploring treatment methods via the coagulation/fibrinolysis pathways.

Autoimmune Thyroid Diseases in Chronic Spontaneous Urticaria: The Role of Hormones, Anti-Thyroid Antibodies, and Ultrasound

Background/Objectives: Chronic spontaneous urticaria (CSU) is an immune-mediated skin disorder, with increasing evidence suggesting its association with autoimmune thyroid diseases. The presence of antithyroid antibodies (anti-TPO and anti-TG) and autoimmune thyroid disease indicates shared immunological mechanisms in the pathogenesis of both conditions. This study examines the prevalence of autoimmune thyroid changes in patients with CSU. Methods: The study was conducted as a combined retrospective-prospective observational analysis. It included 43 patients with CSU and 50 healthy participants in the control group. Thyroid hormone levels (TSH, T3, T4), anti-TPO and anti-TG antibodies, as well as ultrasound characteristics of the thyroid gland, were analyzed. Results: In patients with CSU, a higher prevalence of hypothyroidism (27.9% vs. 4% in the control group), hypertension, asthma, and diabetes were observed. Elevated levels of anti-TPO antibodies were found in 51.2% of CSU patients, compared to only 6% in the control group (p < 0.001). Similarly, anti-TG antibodies were increased in 41.9% of CSU patients, compared to 4% in the control group. Additionally, ultrasound analysis revealed significant differences in thyroid morphology, with a heterogeneous structure observed in 72.1% of CSU patients, compared to only 14% in the control group (p < 0.001). Nodular changes were present in 34.88% of CSU patients, whereas the prevalence in the control group was only 6% (p < 0.001). Conclusions: Our results confirm a significant association between CSU and autoimmune thyroid diseases, including a high prevalence of anti-TPO and anti-TG antibodies, hypothyroidism, diffuse heterogeneity, and nodular changes. Additionally, elevated T3 hormone levels were common among CSU patients, while T4 levels did not differ significantly from those in the control group.

A retrospective analysis of factors influencing response to omalizumab treatment in Indian patients with antihistamine refractory chronic spontaneous urticaria

Background

Chronic spontaneous urticaria (CSU) presents as a persistent and distressing condition, with varying treatment responses. Omalizumab, a monoclonal anti-IgE antibody, has shown efficacy in managing antihistamine (AH1)-refractory CSU, but its varied response patterns and associated factors remain understudied, particularly in India.

Methods

We conducted a retrospective study involving 81 antihistamine-resistant CSU patients treated with omalizumab at a tertiary care center in Northern India between 2018 and 2023. Baseline characteristics, treatment response, and adverse effects were analyzed. Patients were categorized into various response groups based on treatment timelines and biomarker correlations.

Results

We observed 65% achieved symptom cessation (group 1) following a single omalizumab dose, while 21% responded between second and third doses (group 2). A subset (7.4%) necessitated increased dosing frequency (group 3) for symptom control. Additionally, 6.2% showed persistent symptoms despite increased dosing frequency (group 4), exhibiting distinctive biomarker profiles indicative of an autoimmune endotype. Notably, 27.1% experienced exacerbations during treatment, emphasizing the need for tailored management approaches and response expectations.

Conclusion

Omalizumab demonstrated remarkable efficacy in the treatment of AH1-refractory CSU, with a good safety profile. This study highlights the complexity of treatment response to omalizumab and the potential utility of biomarkers in guiding personalized therapeutic strategies. Further research into biomarker-based endotypes is warranted to optimize CSU management.

Clinical burden, treatment, and disease control in patients with chronic spontaneous urticaria: Real-world evidence

BACKGROUND

Chronic spontaneous urticaria (CSU) is an unpredictable inflammatory skin condition with substantial clinical burden that affects 0.23% to 0.78% of the US population.

OBJECTIVE

To describe the incidence and prevalence of patients with a record of CSU diagnosis, treatment patterns, disease control, and clinical and economic burden in a US cohort of patients with CSU.

METHODS

Adults with a record of CSU diagnosis within the US HealthVerity claims database were eligible. Age- and gender-adjusted prevalence/incidence rates were calculated for January 2017 to December 2022. Clinical characteristics were described during the 1 year before CSU diagnosis (baseline) and the time after (follow-up). Proxy events representing uncontrolled CSU (any record of prescriptions for corticosteroids, biologics, or immunosuppressants [excluding all antihistamines and over-the-counter medication] or any CSU-related inpatient admissions or emergency department or urgent care visits) were used to identify patients with uncontrolled CSU. Health care resource utilization (HCRU) and health care costs were described.

RESULTS

Overall, 200,298 patients were followed-up for a median of 2.3 years after diagnosis. Estimated cumulative prevalence of diagnosed CSU was 0.57% (women: 0.80%; men: 0.32%). The average annual incidence rate was 0.08%. Corticosteroids were the most prescribed treatment during follow-up among the 166,195 patients prescribed at least 1 treatment (94.3%). Proxy events were observed in 59.1% of the patients. HCRU and health care costs increased from baseline in patients with uncontrolled CSU during follow-up.

CONCLUSION

Of patients with CSU who were prescribed treatment, more than 50% experienced uncontrolled CSU, which was associated with increased HCRU and health care costs.

Factors associated with the efficacy of omalizumab treatment in chronic spontaneous urticaria

BACKGROUND

Omalizumab is a preferred treatment in antihistamine-refractory chronic spontaneous urticaria (CSU) patients. However, factors that may impact treatment response remain to be explored.

OBJECTIVE

This study aimed to examine the factors affecting treatment response in CSU patients receiving omalizumab.

METHODS

This was a retrospective study that included 123 patients who received omalizumab treatment for CSU between January 2015 and April 2024. After administering omalizumab, we evaluated therapeutic efficacy with the urticaria control test (UCT). According to UCT, patients were classified as complete responders, partial responders, and nonresponders.

RESULTS

The median age of the patients was 42 (31-50) years, and there were 77 (62.9%) female patients. Sixty-four (52%) patients exhibited complete response, and 43 (35%) patients exhibited partial response to omalizumab treatment, whereas 16 (13%) patients were nonresponders. Autoimmune disease (AID) was present in 31 (25.2%) patients. The most common AID was thyroid autoimmunity, seen in 24 (77.4%) patients. AID was significantly higher in omalizumab treatment nonresponders than in partial and complete responders. The presence of an autoimmune thyroid disease was an independent risk factor for failure to respond to omalizumab treatment. Baseline IgE levels were significantly higher in omalizumab treatment responders with a complete response compared to those with a partial response and nonresponders.

CONCLUSION

Response to omalizumab treatment was influenced by the presence of an AID and baseline serum total IgE level. A concurrent autoimmune thyroid disease was found to be an independent risk factor affecting failed treatment response. Factors that can predict response to omalizumab treatment can help guide patients to more effective treatment.

Epidemiological insights into chronic urticaria, vitiligo, alopecia areata, and herpes zoster following COVID-19 infection: A nationwide population-based study

The long-term complications of coronavirus disease 2019 (COVID-19) continue to cause global concern. This study aimed to estimate the incidence and risk of chronic urticaria, vitiligo, alopecia areata, and herpes zoster following COVID-19 infection. Only participants confirmed by real-time reverse transcription-polymerase chain reaction tests to have COVID-19 were enrolled in the COVID-19 group. The matched cohort without COVID-19 was enrolled randomly at a ratio of 1:1. The incidence and risk of chronic urticaria, vitiligo, alopecia areata, and herpes zoster were assessed in both groups using univariable and multivariable Cox proportional hazard analyses. A total of 4 976 589 COVID-19 patients (9.58% of the total population of South Korea) and an equivalent number of matched non-infected control subjects were analyzed. Chronic urticaria, vitiligo, alopecia areata, and herpes zoster manifested at higher rates within the COVID-19 cohort, even after multivariable adjustment for potential confounders. COVID-19 may increase the risk of developing chronic urticaria, vitiligo, alopecia areata, and herpes zoster.

Relevance of the basophil activation test in a cohort of 240 patients with chronic spontaneous urticaria

BACKGROUND

The basophil activation test (BAT) is considered to be the best biomarker to predict autoimmune chronic spontaneous urticaria (aiCSU). To date, few studies have investigated the utility of BAT in real-world clinical practice, the role of aiCSU biomarkers in relation to omalizumab therapy and the degree of association between different aiCSU tests.

OBJECTIVES

To analyse the clinical and laboratory features of a prospective cohort with chronic spontaneous urticaria (CSU) according to their BAT status, as well as to study omalizumab efficacy according to aiCSU biomarkers.

METHODS

A prospective study was conducted from 2010 to 2024 in patients with CSU. BAT alongside other laboratory tests were performed, and clinical and therapeutic features were prospectively collected. Data obtained were compared according to BAT status (positive vs. negative). Furthermore, omalizumab drug survival was typified according to aiCSU biomarkers.

RESULTS

In total, 240 patients were included in the study. Patients who were BAT positive presented more frequently with low IgE levels, higher occurrence of IgG antithyroid peroxidase (anti-TPO) positivity, autologous serum skin test (ASST) positivity, basopenia and eosinopenia. Multivariate logistic regression revealed that ASST [odds ratio (OR) 7.69, 95% confidence interval (CI) 2.81-21.0] and anti-TPO (OR 2.63, 95% CI 1.05-6.61) were associated with BAT positivity. All aiCSU biomarkers (BAT, ASST, combined ASST/BAT positivity and low IgE/anti-TPO+) were associated with significantly shorter omalizumab survival because of treatment failure. In the cohort, both low IgE/anti-TPO+ and ASST were associated with BAT positivity.

CONCLUSIONS

The use of BAT in clinical practice delineates a subgroup of patients with specific clinical, laboratory and therapeutic features, including increased omalizumab failure.

Tezepelumab for the treatment of chronic spontaneous urticaria: Results of the phase 2b INCEPTION study

BACKGROUND

Tezepelumab, an mAb inhibiting thymic stromal lymphopoietin, is an upstream-targeted therapy with potential to inhibit multiple pathways in chronic spontaneous urticaria (CSU).

OBJECTIVE

We sought to evaluate tezepelumab efficacy and safety in patients with CSU despite treatment with second-generation H1 antihistamines.

METHODS

This phase 2b study randomized 183 patients (125 anti-IgE therapy-naive; 58 anti-IgE therapy-experienced) to placebo every 2 weeks, tezepelumab 210 mg every 4 weeks, tezepelumab 420 mg every 2 weeks, or omalizumab 300 mg every 4 weeks (anti-IgE-naive only) for 16-week treatment. The primary end point was change from baseline in weekly Urticaria Activity Score (UAS7) at week 16. Safety and exploratory end points were evaluated through week 32.

RESULTS

The 16-week primary end point was not met. In the overall population, tezepelumab 210 mg and 420 mg did not significantly improve UAS7 versus placebo (least squares mean [SE]: -13.5 [1.6] and -14.7 [1.5], respectively, vs -13.6 [1.6], P = .99, nominal and P = .60, nominal, respectively). Greater improvement in UAS7 versus placebo was observed in the anti-IgE-naive tezepelumab-treated populations (nominal significance); a trend toward significance was observed with omalizumab. In the anti-IgE-naive population, there was delayed, sustained, 32-week off-treatment improvement in UAS7 versus placebo with tezepelumab 210 mg (nominally significant) and 420 mg (trend), but not with omalizumab. This effect was larger in patients with lower baseline IgE levels and longer CSU duration and accompanied sustained IL-5 and IL-13 reductions. Tezepelumab and placebo safety findings were balanced.

CONCLUSION

Although the 16-week primary end point was not met, tezepelumab showed post-treatment reductions in CSU activity through week 32, suggesting a delayed, sustained, thymic stromal lymphopoietin blockade treatment effect.

Clinical and Pathophysiological Tangles Between Allergy and Autoimmunity: Deconstructing an Old Dichotomic Paradigm

Allergic and autoimmune disorders are characterised by dysregulation of the immune responses to otherwise inert environmental substances and autoantigens, leading to inflammation and tissue damage. Their incidence has constantly increased in the last decades, and their co-occurrence defies current standards in patient care. For years, allergy and autoimmunity have been considered opposite conditions, with IgE and Th2 lymphocytes cascade driving canonical allergic manifestations and Th1/Th17-related pathways accounting for autoimmunity. Conversely, growing evidence suggests that these conditions not only share some common inciting triggers but also are subtended by overlapping pathogenic pathways. Permissive genetic backgrounds, along with epithelial barrier damage and changes in the microbiome, are now appreciated as common risk factors for both allergy and autoimmunity. Eosinophils and mast cells, along with autoreactive IgE, are emerging players in triggering and sustaining autoimmunity, while pharmacological modulation of B cells and Th17 responses has provided novel clues to the pathophysiology of allergy. By combining clinical and therapeutic evidence with data from mechanistic studies, this review provides a state-of-the-art update on the complex interplay between allergy and autoimmunity, deconstructing old dichotomic paradigms and offering potential clues for future research.

Advances in Biologic Therapies for Allergic Diseases: Current Trends, Emerging Agents, and Future Perspectives

Biologic therapies have revolutionized the treatment of severe allergic diseases, including asthma, atopic dermatitis (AD), chronic spontaneous urticaria (CSU), chronic rhinosinusitis with nasal polyps (CRSwNP), eosinophilic gastrointestinal diseases (EGIDs), and allergic rhinitis (AR). These molecularly targeted agents provide significant benefits for patients unresponsive to conventional treatments by addressing underlying immune mechanisms, particularly type 2 inflammation driven by cytokines such as IL-4, IL-5, and IL-13. Recent advancements include biologics targeting alarmins like thymic stromal lymphopoietin (TSLP) and IL-33, which may address both type 2 and non-type 2 inflammation, broadening their therapeutic scope. Despite their effectiveness, biologics remain expensive, posing socioeconomic challenges, and there are concerns regarding long-term safety and inter-individual variability in responses. Promising innovations such as bispecific antibodies and ultra-long-acting agents are under investigation, alongside digital health tools like remote biomarker monitoring and AI-driven decision support systems, which aim to enhance personalized care. However, disparities in access, particularly for underserved populations, underscore the need for policy reforms and affordable biosimilars. This review synthesizes recent findings and emerging trends, highlighting the evolving role of biologics in transforming allergic disease management and offering insights into future research directions.

Utility of serum biomarkers in real-world practice for predicting response to omalizumab therapy in patients with chronic spontaneous urticaria

Background

Omalizumab (OMA), a recombinant humanized IgG monoclonal anti-IgE antibody, is approved for treatment for chronic spontaneous urticaria (CSU) refractory to second-generation H1-antihistamine (SGAH) therapy. However, currently, there are no validated serum biomarkers to reliably predict response to OMA treatment.

Objective

We explored the real-world clinical utility of using serum biomarkers for predicting response to OMA for CSU patients with disease refractory to high-dose SGAH therapy.

Methods

A single-center, retrospective chart review of CSU patients treated with OMA enrolled patients who had at their initial evaluation collection of a basophil histamine release assay for detecting IgG antibodies targeting FcεR1α subunit before starting OMA treatment. In addition, total IgE, IgG-anti-thyroid peroxidase (TPO), C-reactive protein, and absolute eosinophil count, if available, were analyzed as predictors for OMA response. The validated Outcome and Assessment Information Set Database (OASIS-D) rating system was used to assess responsiveness to OMA.

Results

High levels of IgG-anti-TPO were significantly associated with a poor response to OMA. However, basophil histamine release assay, total IgE, C-reactive protein, and absolute eosinophil count, as well as IgG-anti-TPO/total IgE ratios, were not predictive of a response to OMA therapy.

Conclusions

This real-world study confirms previous reports that a high IgG-anti-TPO level is a reliable predictor of poor response to OMA. However, better validation of basophil histamine release assay and other immunoassays that measure IgG antibodies to FcεR1α subunit are required before they can be recommended as predictors for OMA response. Whether any of these biomarkers are relevant for predicting response to novel advanced therapeutics under current development requires further investigation.

Expression of STAT3, IL27p28 and IL12p35 is deregulated and linked to autoimmune markers in chronic spontaneous urticaria

BACKGROUND

Chronic spontaneous urticaria (CSU) is a common inflammatory disorder characterized by weals, angio-oedema, or both, for more than 6 weeks. Autoimmunity is held to be one of the most frequent causes, but little is known about the expression and relevance of autoimmunity-driving genes in CSU, such as STAT3, STAT1, IL27p28 (IL30) and IL12p35 (IL12A).

OBJECTIVES

To investigate patients with CSU and the expression of STAT3, STAT1, IL27p28 and IL12p35, and possible links to clinical features.

METHODS

We enrolled 26 patients with CSU and 19 healthy controls (HCs) and determined their expression levels of STAT3, STAT1, IL27p28 and IL12p35 by quantitative real-time polymerase chain reaction. Patients were assessed for total IgE and IgG-anti-thyroid peroxidase (TPO), markers of autoimmune CSU.

RESULTS

Patients with CSU showed significantly higher expression of STAT3 but not STAT1: 17 (65%) and 10 (38%) of the 26 had elevated STAT3 expression and STAT3/STAT1 ratios, respectively, as compared with only 1 (5%) of the 19 HCs. High STAT3 expression and STAT3/STAT1 ratios were linked to low IgE and elevated IgG-anti-TPO. As compared with HCs, patients with CSU had markedly lower and correlated IL27p28 and IL12p35 mRNA expression levels. Low IL27p28 and IL12p35 expression levels were linked to higher STAT3/STAT1 ratios and low IgE.

CONCLUSIONS

STAT3 upregulation and higher STAT3/STAT1 ratios, along with IL27p28 and IL12p35 downregulation, clusters with features of autoimmune CSU. The role of STAT3 as a potential pathogenic driver of autoimmune CSU and target of treatment should be explored further.

CT-P39 Compared With Reference Omalizumab in Chronic Spontaneous Urticaria: Results From a Double-Blind, Randomized, Active-Controlled, Phase 3 Study

BACKGROUND

This study compared the therapeutic equivalence of CT-P39 (an omalizumab biosimilar) and EU-approved reference omalizumab (ref-OMA) in patients with chronic spontaneous urticaria.

METHODS

This double-blind, randomized, active-controlled Phase 3 study (NCT04426890) included two 12-week treatment periods (TPs). In TP1, patients received CT-P39 300 mg, ref-OMA 300 mg, CT-P39 150 mg, or ref-OMA 150 mg. In TP2, patients treated with ref-OMA 300 mg were rerandomized to CT-P39 300 mg or ref-OMA 300 mg; patients initially randomized to CT-P39 300 mg continued this regimen; and patients initially randomized to CT-P39 or ref-OMA 150 mg received 300 mg dosing with the same drug. The primary endpoint for the assessment of therapeutic equivalence of CT-P39 300 mg and ref-OMA 300 mg was change from baseline in weekly itch severity score (ISS7) at week 12.

RESULTS

In TP1, 619 patients were randomized (CT-P39 300 mg, n = 204; ref-OMA 300 mg, n = 205; CT-P39 150 mg, n = 107; ref-OMA 150 mg, n = 103). Equivalence was demonstrated between CT-P39 300 mg and ref-OMA 300 mg for mean change from baseline in ISS7 at week 12; confidence intervals (CIs) were within predefined equivalence margins: global analysis: treatment difference 0.77, 95% CI -0.37 to 1.90; US analysis: treatment difference 0.70, 90% CI -0.22 to 1.63. The proportion of patients experiencing ≥ 1 treatment-related adverse event was comparable across groups. Secondary efficacy, quality of life, pharmacokinetic, safety, and immunogenicity outcomes were comparable between groups at a given dose level, with no evident impact of switching.

CONCLUSIONS

Equivalent efficacy was observed between CT-P39 and ref-OMA, with comparable safety also evident.

Long term safety and efficacy of ligelizumab in the treatment of Japanese patients with chronic spontaneous urticaria

BACKGROUND

In Japan, urticaria is a common skin disorder with chronic spontaneous urticaria (CSU) being the most frequent subtype. This study evaluated the safety of ligelizumab (anti-IgE monoclonal antibody) in Japanese CSU patients.

METHODS

This was a Phase 3 multicenter, open-label, single-arm 52-week study in adult Japanese patients with CSU inadequately controlled with locally approved doses of H1-antihistamines. The primary objective reported the safety of ligelizumab 120 mg subcutaneously every 4 weeks, by evaluation of treatment emergent adverse events (TEAE). Secondary objectives evaluated efficacy by absolute change from baseline (CFB) in weekly urticaria activity score (UAS7), and the proportion of patients with UAS7 = 0, and dermatology life quality index (DLQI) = 0-1 over time.

RESULTS

From a total of 66 CSU patients (80.3% females; mean ± SD age 46.4 ± 13.2 years; mean ± SD baseline UAS7 28.7 ± 6.5) enrolled, 53 patients (80.3%) reported ≥1 TEAE during the study, with no severe or serious adverse events, no anaphylaxis events and low frequency of TEAEs leading to treatment discontinuations (6.1%). Absolute mean CFB of UAS7 showed a rapid onset of response at Week 4 (-14.2) with further improvement until end of treatment at Week 52 (-22.9). The proportion of patients achieving UAS7 = 0 improved over time (14.5% at Week 4; 50.0% at Week 52). A sizable proportion of patients achieved DLQI 0-1 with the first dose of ligelizumab (38.5%), and improvements observed throughout the study until Week 52 (68.8%).

CONCLUSIONS

Treatment with ligelizumab 120 mg was well-tolerated with mild to moderate adverse events and was efficacious in Japanese patients.

Etiology, Recent Advances, and Clinical Trials Data for the Treatment of Angioedema: A Review

Angioedema is a health issue that affects parts of the body like the upper pulmonary and gastric pathways and is identified by abrupt, nonpitting enlargement of the skin, mucous membranes, or both. The swelling usually lasts a few hours to 72 hours and may appear as non-puritic, subcutaneous, or submucosal organ edema. It is characterized by localized swelling brought on by the release of histamine. Itching is rare, and usual areas of appearance include the hands, feet, face, and genitalia, with periorbital swelling being the most often. The main objective of this review article is to study in brief the classifications, etiology, pathophysiology, and clinical trial data by describing the recent advancement in the treatment of angioedema. Various research articles obtained from different journals indexed under Scopus and SCI were used to prepare the review article and for illustrative work software such as Biorender and Microsoft Word was used. Histaminemediated angioedema, linked to allergic reactions, coexists with urticaria. Bradykinin-mediated angioedema, exemplified by hereditary angioedema and acquired forms, lacks urticaria. Idiopathic angioedema, with uncertain etiology. Imitated angioedema results from non-IgE-mediated reactions, often induced by medications. It is a complicated medical condition with a variety of causes and mechanisms. Over time, outcomes for patients have been greatly improved by a growing understanding of its etiology, pathophysiology, and available treatments. The field of medical treatment for this difficult problem is always changing, and this is partly due to clinical trials.

NOD-like receptor family pyrin domain containing 3 (rs10754558) gene polymorphism in chronic spontaneous urticaria: A pilot case-control study

BACKGROUND

Chronic spontaneous urticaria (CSU) is a persistent skin condition with no known cause or trigger. The unpredictability of CSU attacks lowers patients' quality of life. NOD-like receptor pyrin domain containing 3 (NLRP3) gene dysregulation can result in numerous immunological and inflammatory diseases.

OBJECTIVE

This case-control study aimed to determine the association between the NLRP3 inflammasome (rs10754558) single nucleotide polymorphism (SNP) and the occurrence, severity and etiology of CSU.

METHODS

Each study group included 62 participants; all were subjected to CSU severity evaluation by the urticaria activity score (UAS), autologous serum skin testing (ASST) and NLRP3 (rs10754558) genotyping.

RESULTS

The NLRP3 (rs10754558) CG genotype was the most predominant in both study groups, followed by the CC genotype (41.9 %) in the CSU group and the GG genotype (25.8 %) in the control group. Most of the CSU group (66.1 %) had the C allele, compared to most controls (53.2 %) with the G allele. The frequency of NLRP3 (rs10754558) genotypes and alleles did not differ significantly according to the severity of CSU by UAS (P > 0.05). The prevalence of the CC genotype was significantly higher among the ASST-positive CSU patients. The C allele elevated the likelihood of positive ASST in CSU patients by 21 times, suggesting the autoimmune theory of CSU. None of the ASST-positive patients had the GG genotype.

CONCLUSION

The NLRP3 inflammasome (rs10754558) C allele may be associated with CSU risk but not severity by UAS. It may also be associated with ASST positivity which suggests a connection between the C-allele and the autoimmune notion of CSU.

Anti-IgE therapy in chronic rhinosinusitis with nasal polyps

Chronic rhinosinusitis with nasal polyps (CRSwNP) is a chronic inflammatory condition characterized by type 2 (T2) immune responses with significant impacts on quality of life and health care costs. Local IgE production in nasal polyp tissue plays a key role in the T2 inflammatory cascade. Omalizumab, an anti-IgE monoclonal antibody, is an effective treatment for some patients with CRSwNP regardless of the patient's allergic status. Clinical trials, including the pivotal POLYP 1 and POLYP 2 studies, demonstrated omalizumab's efficacy in reducing nasal polyp size, improving symptom scores, and enhancing quality of life, particularly in patients with comorbid asthma and aspirin-exacerbated respiratory disease. As we summarize in this review, omalizumab's effect appears to involve the reduction in local IgE and T2 inflammation; however, this remains poorly understood. Notably, omalizumab's effectiveness appears to be partially sustained after long-term therapy, though symptoms and inflammation begin to return at discontinuation. Ongoing research is needed to determine the optimal duration of therapy and potential for biologics to modify the disease course. Additionally, further studies are needed to identify biomarkers to predict treatment response and to compare omalizumab with other biologics such as dupilumab in head-to-head trials. Omalizumab is one of the key T2-targeted therapeutic options for CRSwNP, with sustained effectiveness and strong safety profile.

Eosinophilic cationic protein and D-Dimer are potential biomarkers to predict response to antihistamines but not to omalizumab in chronic spontaneous urticaria

INTRODUCTION

Biomarkers that could reliably anticipate the effectiveness of antihistamines and omalizumab in treating chronic spontaneous urticaria (CSU) have not been conclusively identified. Our objective was to examine how eosinophilic cationic protein (ECP), tryptase, D-dimer, and total Immunoglobulin E (IgE) impact the response to antihistamine and omalizumab treatments in individuals with CSU.

METHODS

In this cross-sectional retrospective study, CSU patients that had undergone treatment with either antihistamines or omalizumab for a minimum of 12 weeks between 2015 and 2021 at an Allergy and Immunology Department were analyzed. Several demographic and laboratory parameters including eosinophil counts, mean platelet volüme (MPV), sedimentation, C-reactive protein (CRP), antinuclear antibodies (ANA) and Anti-thyroperoxidase (Anti-TPO) and total IgE, tryptase, ECP and D-dimer were retrived from patient files. The association of these biomarkers with Urticaria Control Test (UCT) and the effect of these biomarkers on treatment response were evaluated. Treatment response was assessed using the UCT, with a score of UCT ≥ 12 indicating a responder and UCT < 12 indicating a non responder.

RESULTS

The patients in the omalizumab group were older, had a longer disease duration and had worse urticaria control (lower baseline UCT scores). 421 patients were treated with antihistamines and 88 patients were treated with omalizumab. ECP was found to be inversely correlated with baseline UCT (p < 0.001 r=-0.268). ECP and D-dimer levels of non-responder patients in the antihistamine group were significantly higher than in responder patients (ECP: 49 ng/mL vs 28.1 ng/mL, p < 0.001) (D-dimer: 0.60 mg/L vs 0.30 mg/L, p < 0.001), while there were no significant difference in terms of tryptase and total IgE. These four biomarkers were similar, in omalizumab responders and non responders.

CONCLUSION

In this study with CSU, we looked at predictors of responses to treatments. ECP can serve as a marker of poor urticaria control and may predict antihistamine refractoriness along with D-dimer.

Biomarkers for Short-Term Omalizumab Response in Chronic Spontaneous Urticaria

BACKGROUND

Omalizumab, a monoclonal antibody targeting immunoglobulin E (IgE), is approved for adults and adolescents (12 years or older) with chronic spontaneous urticaria (CSU) that does not respond to high-dose antihistamines. In Korea, there is limited research on predictive biomarkers for omalizumab response in CSU patients.

OBJECTIVE

This retrospective, single-institution study aimed to identify clinical parameters predicting omalizumab response in Korean CSU patients.

METHODS

We analyzed records of CSU patients aged 19 or older starting omalizumab between January 2017 and October 2019. Omalizumab efficacy was assessed using the Urticaria Activity Score summed over 7 days (UAS7), categorized as well-controlled, mild, moderate, or severe. Ninety CSU patients participated in this study.

RESULTS

Among these, improvements in UAS7 categories from baseline to 12 weeks of treatment were observed in 78 patients, while 12 patients showed no significant efficacy. The present study identified potential biomarkers that could predict a patient's response to omalizumab, including disease duration and total serum IgE levels (p=0.022, p=0.046). Notably, a significant correlation was observed between higher detection rates in multiple antigen simultaneous test (MAST) food testing and lower treatment responses (p=0.033).

CONCLUSION

Shorter disease duration of CSU and elevated initial serum total IgE level may serve as potential predictive biomarkers for the responsiveness to omalizumab. Furthermore, a higher MAST food detection rate seemed to correlate with a less favorable treatment response, suggesting patients with a high MAST food detection rate might benefit from a food evaluation in addition to omalizumab treatment.

Treatment of patients with evidence of mast cell-mediated itch in the absence of hives with omalizumab

PURPOSE

The presence of wheals or hives has been viewed as a hallmark symptom of urticaria, a highly debilitating disease. This study explores our experience with omalizumab in patients with apparent mast-cell mediated pruritus in the absence of hives.

MATERIALS AND METHODS

This is a retrospective case series examining all patients with mast cell-mediated pruritus in the absence of hives from April 2022 to May 2024 at a tertiary referral clinic at Icahn School of Medicine at Mount Sinai in New York. Peak pruritus-numerical rating scale (PP-NRS) itch score changes over time were recorded and analyzed.

RESULTS

Six patients (67% women; mean [SD] age, 47.67 [13.52] years) were included in the analysis. The median [IQR] pruritus PP-NRS itch score before omalizumab injection was 9 [6 - 10] and the final median [IQR] PP-NRS itch score was 2.5 [0 - 5]. The mean [SD] reduction in the PP-NRS itch score was 6 [3.16].

CONCLUSIONS

This study suggests that patients with evidence of mast cell-mediated pruritus can be identified based on clinical features and may benefit from omalizumab therapy.

Association between immune cells and urticaria: a bidirectional Mendelian randomization study

Urticaria is characterized by transient itchy symptoms on the skin, usually accompanied by swelling, which is caused by mast cell activation leading to increased vascular permeability and dilation of the dermis. Urticaria involves recurrent activation of mast cells, T cells, eosinophils, and other immune cells around lesioned venules, with complex regulatory systems affecting mast cell functions, potentially contributing to urticaria pathogenesis. The direct causal relationship between immune cells and urticaria is currently unclear. To address this, our study utilized a bidirectional Mendelian randomization analysis, employing instrumental variables (IVs) associated with immune cells and urticaria, to investigate this causal relationship. First, by utilizing Genome-wide Association Study (GWAS) data, we identified 31 immunophenotypes associated with urticaria risk, with 18 increasing and 13 decreasing the risk. Through rigorous criteria, we identified 4 immunophenotypes that have a strong causal relationship with urticaria. Notably, HLA DR+ CD4+AC, CD45 on CD8br, and HLA DR on plasmacytoid dendritic cells were associated with an increased risk, while CD8dim NKT %lymphocyte was identified as a protective factor. Sensitivity analyses, including the MR-Egger intercept test, scatter plots, funnel plots, and leave-one-out analysis, supported the robustness of the findings. Reverse MR analysis suggested an inverse causal effect of urticaria on CD8dim NKT %lymphocyte, reinforcing the potential bidirectional nature of the relationship between urticaria and immune cell phenotypes. Our research substantiates the bidirectional causal relationship between immune cells and urticaria, thus benefiting for urticaria-targeted therapy development.

Exploring mechanisms of skin aging: insights for clinical treatment

The skin is the largest organ in the human body and is made up of various cells and structures. Over time, the skin will age, which is not only influenced by internal factors, but also by external environmental factors, especially ultraviolet radiation. Aging causes immune system weakening in the elderly, which makes them more susceptible to dermatosis, such as type 2 inflammatory mediated pruritus. The immune response in this condition is marked by senescent cells consistently releasing low amounts of pro-inflammatory cytokines through a senescence-associated secretory phenotype (SASP). This continuous inflammation may accelerate immune system aging and establish a connection between immune aging and type 2 inflammatory skin diseases. In addition, two chronic pigmentation disorders, vitiligo and chloasma, are also associated with skin aging. Aged cells escape the immune system and accumulate in tissues, forming a microenvironment that promotes cancer. At the same time, "photoaging" caused by excessive exposure to ultraviolet radiation is also an important cause of skin cancer. This manuscript describes the possible links between skin aging and type 2 inflammation, chronic pigmentation disorders, and skin cancer and suggests some treatment options.

Chronic Spontaneous Urticaria: A Review

Importance

Chronic spontaneous urticaria affects approximately 1% of the general population worldwide, including approximately 3 million people in the US, impairs patients' quality of life, and is associated with multiple comorbidities.

Observations

Chronic spontaneous urticaria affects patients of any age but is most common in females aged 30 to 50 years. Diagnosis is based on clinical presentation, ie, spontaneously recurring wheals, angioedema, or both. Chronic spontaneous urticaria persists for more than 1 year in most patients (1 or repeated episodes) and may present with comorbidities including chronic inducible urticaria (>10%), autoimmune thyroiditis (approximately 20%), metabolic syndrome (6%-20%), and anxiety (10%-31%) and depression (7%-29%). Known autoimmune endotypes (subtypes of urticaria defined by distinct pathogenesis) of chronic spontaneous urticaria are mediated by mast cell-activating IgE and/or IgG autoantibodies (>50%). Approximately 40% of patients with chronic spontaneous urticaria have a Dermatology Life Quality Index of more than 10, corresponding to a very large or extremely large negative effect on quality of life. Second-generation H1 antihistamines are first-line treatment; partial or complete response, defined as a reduction in urticaria symptoms of greater than 50%, is observed in approximately 40% of patients. The 2022 international urticaria guideline recommends the monoclonal anti-IgE antibody omalizumab as second-line treatment for antihistamine-refractory chronic spontaneous urticaria. However, at least 30% of patients have an insufficient response to omalizumab, especially those with IgG-mediated autoimmune urticaria. Cyclosporine, used off-label, can improve symptoms in approximately 54% to 73% of patients, especially those with autoimmune chronic spontaneous urticaria and nonresponse to omalizumab, but has adverse effects such as kidney dysfunction and hypertension.

Conclusions and Relevance

Chronic spontaneous urticaria is an inflammatory skin disease associated with medical and psychiatric comorbidities and impaired quality of life. Second-generation H1 antihistamines are first-line treatment, omalizumab is second-line treatment, and cyclosporine is third-line treatment for chronic spontaneous urticaria.

Distinct Clinical Profiles of IgE and IgG Autoantibodies to Thyroid Peroxidase in Chronic Spontaneous Urticaria

PURPOSE

In chronic spontaneous urticaria (CSU), autoimmune thyroid disease is the most common autoimmune comorbidity, and many CSU patients have immunoglobulin (Ig)E or IgG autoantibodies to thyroid peroxidase (TPO). It remains unclear how anti-TPO IgE and IgG autoantibodies are linked to each other and are associated with CSU features, activity, and therapeutic responses.

METHODS

CSU patients (n = 146, 92 females, mean age 42.9 years) and healthy normal controls (NCs, n = 30) were assessed for anti-TPO IgE and IgG by enzyme-linked immunosorbent assay, and the clinical and laboratory profiles, disease activity (UAS7), and response to 3 months of H1-antihistamine treatment were evaluated for anti-TPO IgE-positive and/or IgG-positive patients.

RESULTS

Among 146 CSU patients, 67 (46%, NCs: 6.6%) had elevated anti-TPO IgE and/or IgG, and 32 (22%), 35 (24%), and 5 (3%) had elevated anti-TPO IgE, anti-TPO IgG, and both, respectively. Of the patients with anti-TPO IgE and/or IgG, 44% (n = 27) had anti-TPO IgE but not IgG, 48% (n = 30) had anti-TPO IgG but not IgE, and only 8% (n = 5) had anti-TPO IgE and IgG. Compared to anti-TPO IgE-negative patients, anti-TPO IgE-positive ones had greater rates of atopy and antihistamine responses and lower disease activity (UAS7). Anti-TPO IgG-positive patients had greater rates of angioedema and elevated levels of anti-thyroglobulin IgG than anti-TPO IgG-negative patients.

CONCLUSIONS

Forty-six percentages of CSU patients have autoantibodies to TPO; most have either IgE or IgG autoantibodies but not both. Anti-TPO IgE and anti-TPO IgG come with distinct CSU profiles, including treatment responses.

The decrease in peripheral blood basophils in a mouse model of IgE-induced inflammation involves their migration to lymph nodes

BACKGROUND

During the active phase of urticaria, a decrease in peripheral blood basophils, known as basopenia, is observed. We previously reported that basopenia occurs as a result of basophils migrating to the skin in a contact dermatitis model where a Th2 response is induced with oxazolone.

OBJECTIVE

Although there is currently no established model for urticaria, given that urticaria is an IgE-mediated immediate-type allergic reaction, we aimed to determine whether an IgE-mediated model could reproduce the decrease in basophils in peripheral blood observed during the active phase of urticaria.

METHODS

Mice were pretreated with 2,4,6-trinitrophenylhaptene (TNP)-specific IgE and basophil dynamics were examined following stimulation with TNP-ovalbumin. Mast cell-deficient WBB6F1-KitW/KitW-v mice were used to investigate the role of mast cells in this IgE-mediated model.

RESULTS

Following stimulation, we observed immediate ear swelling and basopenia after 0.5 hours. However, the number of basophils observed in the skin lesions was low, while a higher number of basophils were observed in the antigen-draining lymph nodes (LN). In mast cell-deficient mice, no increase in basophils in the LN was observed, reflecting reduced antigen influx into the LN, but basophils remained in the skin.

CONCLUSIONS

In the IgE-mediated mouse model, basopenia was observed, which coincided with the induction of inflammation in the skin. The migration of basophils to the LN in this model suggests that the systemic immune system, including the LN, should be considered when exploring the pathogenesis of urticaria in humans.

Chronic Spontaneous Urticaria: Current and Emerging Biologic Agents

Antihistamine refractory chronic spontaneous urticaria (CSU) has a prevalence of up to 50%. Anti-immunoglobulin E (IgE) therapies have revolutionized management of CSU, yet refractory cases persist, suggesting a role for biologic agents that impact alternative routes of mast cell stimulation independent of cross-linking at FcεR1. This review addresses anti-IgE and Th2-targeted therapies in the management of CSU. In addition, we explore novel treatments targeting alternative pathways of mast cell activation including MAS-related G protein-coupled receptor-X2 and sialic acid-binding immunoglobulin-like lectin-6, inhibiting intracellular signaling via Bruton's tyrosine kinase, and disrupting KIT activation by SCF.

Key differences between chronic inducible and spontaneous urticaria

Introduction

The latest international EAACI/GA²LEN/EuroGuiDerm/APAAACI guideline for urticaria recommends limited laboratory testing for chronic spontaneous urticaria (CSU) and selective testing for only certain chronic inducible urticaria (CIndU) subtypes, though the rationale for these recommendations is poorly explained. This study aimed to improve the understanding of CIndU subtypes by comprehensively comparing their demographic, clinical, and laboratory characteristics with those of the better-characterized CSU.

Methods

We conducted a retrospective analysis of 567 patients (median age 41 years, 67% female) diagnosed with CSU, symptomatic dermographism (SD), cold urticaria (ColdU), cholinergic urticaria (CholU), and delayed pressure urticaria (DPU).

Results

Our findings revealed that patients with SD, ColdU, and CholU had lower levels of C-reactive protein (CRP), higher total serum immunoglobulin E (IgE) levels, and higher basophil counts compared to CSU patients. These subtypes also had distinct demographic and clinical features, such as a younger age of onset and a longer disease duration. In contrast, patients with DPU had significantly higher CRP levels and neutrophil counts compared to those with CSU.

Discussion

These findings highlight the heterogeneity among chronic urticaria subtypes, suggesting that a tailored approach to laboratory testing may be more effective. The distinct immunological and clinical features observed in CIndU subtypes suggest a need for subtype-specific diagnostic and therapeutic guidelines.

Mast cell signaling and its role in urticaria

Chronic urticaria is a mast cell (MC)-driven disease characterized by the development of itching wheals and/or angioedema. In the last decades, outstanding progress has been made in defining the mechanisms involved in MC activation, and novel activating and inhibitory receptors expressed in MC surface were identified and characterized. Besides an IgE-mediated activation through high-affinity IgE receptor cross-linking, other activating receptors, including Mas-related G-protein-coupled receptor-X2, C5a receptor, and protease-activated receptors 1 and 2 are responsible for MC activation. This would partly explain the reason some subgroups of chronic spontaneous urticaria (CSU), the most frequent form of urticaria in the general population, do not respond to IgE target therapies, requiring other therapeutic approaches for improving the management of the disease. In this review, we shed some light on the current knowledge of the immunologic and nonimmunologic mechanisms regulating MC activation in CSU, considering the complex inflammatory scenario underlying CSU pathogenesis, and novel potential MC-targeted therapies, including surface receptors and cytoplasmic signaling proteins.

MURDA: Multisource Unsupervised Raman Spectroscopy Domain Adaptation Model with Reconstructed Target Domains for Medical Diagnosis Assistance

Artificial intelligence combined with Raman spectroscopy for disease diagnosis is on the rise. However, these methods require a large amount of annotated spectral data for modeling to achieve high diagnostic accuracy. Annotating labels consumes significant medical resources and time. To reduce dependence on labeled medical data resources, we propose a method called Multisource Unsupervised Raman Spectroscopy Domain Adaptation Model with Reconstructed Target Domains (MURDA). It transfers knowledge learned from source domain data sets of different diseases to an unlabeled target domain data set. Compared to knowledge transfer from a single source domain, knowledge from multiple disease source domains provides more generalized knowledge. Considering the diversity of autoimmune diseases and the limited sample size, we apply MURDA to assist in the medical diagnosis of autoimmune diseases. Additionally, we propose a Double-Branch Multiscale Convolutional Self-Attention (DMCS) feature extractor that is more suitable for spectral data feature extraction. On three sets of serum Raman spectroscopy data sets for autoimmune diseases, the multisource domain adaptation diagnostic accuracy of MURDA was superior to traditional single source and multisource models, with accuracy rates of 73.6%, 83.4%, and 82.9%, respectively. Compared with pure source tasks without domain adaptation, it improved by 15.1%, 36%, and 21.6%, respectively. This demonstrates the effectiveness of Raman spectroscopy combined with MURDA in diagnosing autoimmune diseases. We investigated the important decision dependency peaks in migration tasks, providing assistance for future research on artificial intelligence combined with Raman spectroscopy for diagnosing autoimmune diseases. Furthermore, to validate the effectiveness and generalization performance of MURDA, we conducted experiments on the publicly available RRUFF data set, exploring the application of multisource unsupervised domain adaptation in more Raman spectroscopy scenarios.

High rates of mood disorders in patients with chronic idiopathic eosinopenia

Background

Mood disorders (MD) are multifactorial disorders. Identifying new biomarkers for the early diagnosis of MD and predicting response to treatment is currently a significant research topic. Both eosinopenia and MD are associated with increased activity of the hypothalamic-pituitary-adrenal axis. The present study, therefore, used a clear definition of chronic idiopathic eosinopenia (CIE) to determine the rate of MD in a large cohort of individuals with CIE.

Methods

This retrospective population-based, case-control study uses data of seven consecutive years from the database of Leumit Health Services (LHS) - a nationwide health maintenance organization in Israel.

Results

Participants were 13928 LHS members with CIE and 27858 negative controls. The CIE group exhibited significantly higher rates of MD than the control group throughout the whole study period, except for atypical depressive disorder at baseline.

Conclusions

CIE might be associated with a higher prevalence of MD. Further basic research should elucidate the pathophysiologic mechanisms linking CIE and MD.

Efficacy and safety of switching to bilastine, an H1-antihistamine, in patients with refractory chronic spontaneous urticaria (H1-SWITCH): a multicenter, open-label, randomized, parallel-group comparative study

Background

For treating patients with refractory chronic spontaneous urticaria (CSU) resistant to standard doses of 2nd generation H1-antihistamines (H1AH) the International and Japanese guidelines recommend increasing H1AH dose. The latter also recommends switching to a different H1AH. This study explored if the efficacy of the standard dose of bilastine 20 mg is non-inferior to that of double-dose of H1AH in patients with refractory CSU.

Methods

This phase IV, multicenter, open-label, randomized, parallel-group trial evaluated the efficacy and safety of switching treatment to bilastine compared to treatment with a 2-fold dose of H1AH in patients with CSU refractory to standard dose H1AH. The primary endpoint was the mean total symptom score (TSS) at Day 5-7 after the start of administration.

Results

Treatment efficacy and safety were evaluated in 128 patients (bilastine, n=64; 2-fold dose of H1AH, n=64). The mean TSS at Day 5-7 after the start of administration was smaller than the non-inferiority margin of 0.8, demonstrating non-inferiority of the bilastine switching group to the double-dose H1AH group (0.17 (95% CI -0.32, 0.67)). No difference in Japanese version of Epworth Sleepiness Scale (JESS), DLQI, and urticaria activity score over 7 consecutive days (UAS7) was observed between the two groups. There were no serious adverse events in either group. H1AH-related adverse events occurred in 5 subjects (8 cases) and 2 subjects (3 cases) in the double-dose H1AH and bilastine groups, respectively.

Conclusions

Switching treatment to bilastine demonstrated non-inferiority to a double-dose of H1AH in terms of efficacy in patients with CSU refractory to standard dose H1AH with a favorable safety profile.

Clinical trial registration

https://jrct.niph.go.jp/latest-detail/jRCTs051180105, identifier jRCTs051180105.

Disease modification in chronic spontaneous urticaria

Chronic spontaneous urticaria (CSU) is a debilitating, inflammatory skin condition characterized by infiltrating immune cells. Available treatments are limited to improving the signs and symptoms. There is an unmet need to develop therapies that target disease-driving pathways upstream of mast cell activation to inhibit or delay the progression of CSU and associated comorbidities. Here, we aim to define disease modification due to a treatment intervention and criteria that disease-modifying treatments (DMTs) must meet in CSU. We have defined disease modification in CSU as a favorable treatment-induced change in the underlying pathophysiology and, therefore, the disease course, which is clinically beneficial and enduring. A DMT must fulfil the following criteria: (1) prevents or delays the progression of CSU, (2) induces long-term, therapy-free clinical remission, which is the sustained absence of CSU signs and symptoms without the need for treatment, and (3) affects the underlying mechanism of CSU, as demonstrated by an effect on disease-driving signals and/or a biomarker. DMTs in CSU should slow disease progression, achieve long-lasting disease remission, target disease-driving mechanisms, reduce mast cell-activating IgE autoantibodies, target cytokine profile polarization, and normalize the gut microbiome and barrier. Treating CSU at the immune system level could provide valuable alternatives to pharmacotherapy in CSU management. Specific DMTs in CSU are yet to be developed, but some show potential benefits, such as inhibitors of Bruton's Tyrosine Kinase, IL-4 and IL-13. Future therapies could prevent CSU signs and symptoms, achieve long-term clinical benefits after discontinuing treatment, and prevent associated concomitant disorders.

In chronic spontaneous urticaria, increased Galectin-9 expression on basophils and eosinophils is linked to high disease activity, endotype-specific markers, and response to omalizumab treatment

BACKGROUND

Galectin-9 (Gal-9) has been implicated in allergic and autoimmune diseases, but its role and relevance in chronic spontaneous urticaria (CSU) are unclear.

OBJECTIVES

To characterize the role and relevance of Gal-9 in the pathogenesis of CSU.

METHODS

We assessed 60 CSU patients for their expression of Gal-9 on circulating eosinophils and basophils as well as T cell expression of the Gal-9 receptor TIM-3, compared them with 26 healthy controls (HCs), and explored possible links with disease features including disease activity (urticaria activity score, UAS), total IgE, basophil activation test (BAT), and response to omalizumab treatment. We also investigated potential drivers of Gal-9 expression by eosinophils and basophils.

RESULTS

Our CSU patients had markedly increased rates of circulating Gal-9+ eosinophils and basophils and high numbers of lesional Gal-9+ cells. High rates of blood Gal-9+ eosinophils/basophils were linked to high disease activity, IgE levels, and BAT negativity. Serum levels of TNF-α were positively correlated with circulating Gal-9+ eosinophils/basophils, and TNF-α markedly upregulated Gal-9 on eosinophils. CSU patients who responded to omalizumab treatment had more Gal-9+ eosinophils/basophils than non-responders, and omalizumab reduced blood levels of Gal-9+ eosinophils/basophils in responders. Gal-9+ eosinophils/basophils were negatively correlated with TIM-3+TH17 cells.

CONCLUSION

Our findings demonstrate a previously unrecognized involvement of the Gal-9/TIM-3 pathway in the pathogenesis CSU and call for studies that explore its relevance.

Lin-CD117+CD34+FcεRI+ progenitor cells are increased in chronic spontaneous urticaria and predict clinical responsiveness to anti-IgE therapy

BACKGROUND

Chronic spontaneous urticaria (CSU) is a common, debilitating skin disorder characterized by recurring episodes of raised, itchy and sometimes painful wheals lasting longer than 6 weeks. CSU is mediated by mast cells which are absent from peripheral blood. However, lineage-CD34hiCD117int/hiFcεRI+ cells in blood have previously been shown to represent a mast cell precursor.

METHODS

We enumerated FcεRI-, FcεRI+ and FcεRIhi lineage-CD34+CD117+ cells using flow cytometry in blood of patients with CSU (n = 55), including 12 patients receiving omalizumab and 43 not receiving omalizumab (n = 43). Twenty-two control samples were studied. Disease control and patient response to omalizumab was evaluated using the urticaria control test. We performed single-cell RNA sequencing (scRNA-Seq) on lineage-CD34hiCD117hi blood cells from a subset of patients with CSU (n = 8) and healthy controls (n = 4).

RESULTS

CSU patients had more lineage-CD34+CD117+FcεRI+ blood cells than controls. Lineage-CD34+CD117+FcεRI+ cells were significantly higher in patients with CSU who had an objective clinical response to omalizumab when compared to patients who had poor disease control 90 days after initiation of omalizumab. scRNA-Seq revealed that lineage-CD34+CD117+FcεRI+ cells contained both lymphoid and myeloid progenitor lineages, with omalizumab responsive patients having proportionally more myeloid progenitors. The myeloid progenitor lineage contained small numbers of true mast cell precursors along with more immature FcεRI- and FcεRI+ myeloid progenitors.

CONCLUSION

Increased blood CD34+CD117+FcεRI+ cells may reflect enhanced bone marrow egress in the setting of CSU. High expression of these cells strongly predicts better clinical responses to the anti-IgE therapy, omalizumab.

Novel insight into MDA-7/IL-24: A potent therapeutic target for autoimmune and inflammatory diseases

Melanoma differentiation-associated gene-7 (MDA-7)/interleukin-24 (IL-24) is a pleiotropic member of the IL-10 family of cytokines, and is involved in multiple biological processes, including cell proliferation, cell differentiation, tissue fibrosis, the inflammatory response, and antitumor activity. MDA-7/IL-24 can regulate epithelial integrity, homeostasis, mucosal immunity and host resistance to various pathogens by enhancing immune and inflammatory responses. Our recent study revealed the mechanism of MDA-7/IL-24 in promoting airway inflammation and airway remodeling through activating the JAK/STAT3 and ERK signaling pathways in bronchial epithelial cells. Herein, we summarize the cellular sources, inducers, target cells, signaling pathways, and biological effects of MDA-7/IL-24 in several allergic and autoimmune diseases. This review also synopsizes recent advances in clinical research targeting MDA-7/IL-24 or its receptors. Based on these advancements, we emphasize its potential as a target for immunotherapy and discuss the challenges of developing immunotherapeutic drugs targeting MDA-7/IL-24 or its receptors in autoimmune and inflammatory disorders.