Allergology International最新文献

Atopy is considered the epidemic of the 21st century, and while decades of research have established a direct link between Th2 cells driving pathogenic IgE-mediated allergic disease, only in the past years have T follicular helper (Tfh) cells emerged as pivotal drivers of these responses. In this review, we will examine the molecular mechanisms governing the IgE response, with a particular emphasis on the key cytokines and signaling pathways. We will discuss the exclusion of IgE-producing B cells from germinal centers and explore the recently established role of follicular T cell function and heterogeneity in driving or curtailing these immune responses. Additionally, we will assess the current state of major monoclonal antibodies and allergen immunotherapies designed to counteract Th2-driven inflammation, as well as reflect on the need to investigate how these biologics impact Tfh cell activity, differentiation, and function, as these insights could pave the way for much-needed therapeutic innovation in the treatment of allergic diseases.

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.

Background: Hypersensitivity pneumonitis (HP) is a complex and heterogenous interstitial lung disease (ILD) that occurs in susceptible individuals due to certain inhaled antigens. Fibrotic-HP is a major underlying disease of progressive pulmonary fibrosis. Therefore, in addition to the radiological features of HP, quantitatively measuring fibrosis is important to evaluate disease severity and progression. The present study aimed to compare three-dimensional computed tomography (3D-CT)-derived lung volumes (LVs) of patients with HP and determine its association with mortality risk.

Methods: In this retrospective and multicenter cohort study, 126 patients diagnosed with HP (fibrotic, n = 72 and non-fibrotic, n = 54) with a confidence level higher than moderate were enrolled. Each lobe LV was measured using 3D-CT at the time of diagnosis and standardized using predicted forced vital capacity. The 3D-CT LV was compared with those of 42 controls and 140 patients with idiopathic pulmonary fibrosis (IPF).

Results: Compared to patients with fibrotic-HP, the standardized total LV was significantly higher in controls and patients with non-fibrotic-HP and was similar in patients with IPF. Longitudinal analyses demonstrated that approximately half of the patients with fibrotic-HP had an annual decrease in total LV. Decreased total and lower-lobe LVs were associated with shorter survival, and were independently associated with mortality together with ongoing exposure to inciting antigens. A composite model consisting of ongoing exposure to inciting antigens and total or lower-lobe LV successfully classified mortality risk into three groups.

Conclusions: Quantitatively measuring standardized LV can help determine disease severity, progression, and mortality risk in patients with fibrotic-HP.

Pollen-food allergy syndrome (PFAS) is caused by cross-reaction of a specific pollen antigen with the corresponding food allergen in sensitized individuals. The manifestations are usually limited to oral symptoms; however, sometimes, rhinitis, respiratory and skin symptoms, and anaphylactic shock may occur. In PFAS pathogenesis, when food containing protein antigens (pan-allergens) with high homology to pollen antigens is ingested, mast cells bound to pollen antigen-specific IgE distributed in the oral mucosa cross-react with the food antigen, causing a local type I allergic reaction. The prevalence of PFAS depends on the geographic conditions, such as the type and amount of pollen in the area. PFAS is prevalent in all regions owing to the wide variety of pollen antigens implicated in the disease, such as alder and grass pollen, even outside of the birch habitat area. Basic research on PFAS is expected to significantly contribute to elucidating the pathogenesis and development of therapeutic strategies for PFAS. Currently, effective treatment for patients with PFAS that allows safe consumption of raw foods is lacking, and avoiding the intake of causative foods is the basis of prevention. Furthermore, allergen immunotherapy for PFAS has not yet been established, but various attempts are underway to develop it into a novel treatment strategy. This review highlights the current research landscape on the pathophysiology, epidemiology, and clinical aspects of PFAS. We outline the research gaps that should be addressed to improve the outcomes of patients with PFAS.

Background: Systemic inhibition of pro-inflammatory cytokines affects the skin microbiome; however, the impact of systemic anti-inflammatory therapy on the skin fungal microbiome is poorly understood. To examine the effects of cytokine inhibition on the fungal community on human skin and oral mucosa, we analyzed the composition of the skin mycobiome before and after IL-23 inhibition.

Methods: The study enrolled 15 psoriasis patients. Swab samples were collected from the psoriasis-free skin of antecubital fossa, post-auricular, and the tongue surface before and after 16 weeks of treatment with anti-IL-23 antibodies. Fungal DNA was sequenced by ITS1 metagenomic analysis, and taxonomic classification was performed.

Results: Data from samples collected from the antecubital fossa revealed that the α diversity of the skin mycobiome decreased significantly after treatment with anti-IL-23 antibodies (p = 0.0120). Fungal DNAs were not amplified in 6/15 swab samples after 16 weeks of IL-23 inhibition; by contrast, sufficiently detected in all 15 samples before treatment (p = 0.0554). A comparison of 9/15 paired samples containing well-detected reads revealed that the percentage of genus Malassezia in the mycobiome fell significantly after treatment with IL-23 inhibitors (before, 29.3% ± 9.9%; after; 8.5% ± 3.4%, p = 0.0137). The mycobiome on post-auricular skin and on the tongue surface showed no marked changes after IL-23 inhibition.

Conclusions: Taken together, the data suggest that inhibition of systemic IL-23 provokes dysbiosis of the mycobiome at the antecubital fossa skin, a finding characterized by reduced fungal diversity and a reduction in the percentage of the genus Malassezia.

Characteristic symptoms of NSAID-exacerbated respiratory disease (N-ERD) include asthma, chronic eosinophilic rhinosinusitis with nasal polyposis, cysteinyl LT (CysLT) overproduction and NSAIDs hypersensitivity. Some N-ERD patients present with episodic treatment-resistant extra-respiratory symptoms (CysLT-associated coronary artery vasospasm, gastroenteritis, or skin rash). Even when using standard treatments for respiratory and extra-respiratory symptoms, including systemic corticosteroids and aspirin desensitization, it is difficult to control the clinical symptoms and severe type 2 inflammation involved with mast cells, eosinophils, ILC2s, and platelet activation. Few treatment options are applicable in a clinical setting. Therefore, identifying effective treatments is essential for managing N-ERD patients who suffer from these conditions. Our previous observational study demonstrated 12-month omalizumab treatment of N-ERD was clinically effective against respiratory symptoms. Despite the remaining eosinophilia, omalizumab significantly reduced urinary LTE₄ and PGD₂ metabolites to near normal levels at steady state. Based on the preliminary study, we demonstrated that omalizumab induced tolerance to aspirin in N-ERD patients 3 months after therapy initiation and suppressed activation of mast cells during 24 h of initiation in a randomized manner. Moreover, omalizumab had significant efficacy against extra-respiratory symptoms at baseline (lacking aspirin exposure) as well as throughout aspirin challenge. This review addresses the latest discoveries related to N-ERD pathogenesis and the significant effectiveness of omalizumab on N-ERD as a mast cell stabilizer. Our findings regarding omalizumab-associated mast cell inhibitory effects are indirect evidence that mast cell dysregulation and, possibly, IgE are pivotal components of N-ERD.

Background: Artificial intelligence (AI) is a promising new technology that has the potential of diagnosing allergic conjunctival diseases (ACDs). However, its development is slowed by the absence of a tailored image database and explainable AI models. Thus, the purpose of this study was to develop an explainable AI model that can not only diagnose ACDs but also present the basis for the diagnosis.

Methods: A dataset of 4942 slit-lamp images from 10 ophthalmological institutions across Japan were used as the image database. A sequential pipeline of segmentation AI was constructed to identify 12 clinical findings in 1038 images of seasonal and perennial allergic conjunctivitis (AC), atopic keratoconjunctivitis (AKC), vernal keratoconjunctivitis (VKC), giant papillary conjunctivitis (GPC), and normal subjects. The performance of the pipeline was evaluated by determining its ability to obtain explainable results through the extraction of the findings. Its diagnostic accuracy was determined for 4 severity-based diagnosis classification of AC, AKC/VKC, GPC, and normal.

Results: Segmentation AI pipeline efficiently extracted crucial ACD indicators including conjunctival hyperemia, giant papillae, and shield ulcer, and offered interpretable insights. The AI pipeline diagnosis had a high diagnostic accuracy of 86.2%, and that of the board-certified ophthalmologists was 60.0%. The pipeline had a high classification performance, and the area under the curve (AUC) was 0.959 for AC, 0.905 for normal subjects, 0.847 for GPC, 0.829 for VKC, and 0.790 for AKC.

Conclusions: An explainable AI model created by a comprehensive image database can be used for diagnosing ACDs with high degree of accuracy.