The role of allergen-specific IgE, IgG and IgA in allergic disease

Cleavage specificity of the pitcher fluid proteases from Nepenthes × miranda and their reduction on allergenicity of cow's milk proteins

In this study, the pitcher fluid proteases from Nepenthes × miranda were researched as a novel protease resource due to their cleavage specificity and ability to reduce the allergenicity of cow's milk proteins. We found that these proteases are particularly efficient at the P1 position with K, L, V, S, I, and R residues and exhibit similar preferences to amino acid residues at the P1' position. It is concluded that P1 is responsible for specificity of pitcher fluid proteases, while P1' tends to show their broadness when hydrolyzation happens. And consistent with the destroying of epitopes, in vivo assays also demonstrated a reduction in allergenicity from both whey protein concentrates and caseins, although the effect on caseins paled to whey protein concentrates. Therefore, these proteases hold significant potential and warrant further development for applications addressing cow's milk protein allergies.

Di(2-ethylhexyl) Phthalate (DEHP) Exacerbates Food Allergy via Intestinal Barrier Dysfunction and Enhancing Allergic Sensitization

Di(2-ethylhexyl) phthalate (DEHP), a ubiquitous plasticizer, has raised concerns due to its potential role in exacerbating food allergy through chronic human exposure. The study aimed to investigate the potential effects of DEHP on ovalbumin (OVA)-induced food allergy and elucidate the underlying mechanisms related to intestinal barrier homeostasis. In OVA-sensitized BALB/c mice, DEHP exposure significantly exacerbated allergic responses by functioning as an immunoadjuvant, as evidenced by heightened anaphylactic symptoms, elevated serum levels of inflammatory mediators (IgE, IgG, IgG1, IgG2), and increased concentrations of histamine and monocyte chemoattractant protein-1 (MCP-1). Furthermore, DEHP disrupted intestinal barrier integrity and impaired mucin secretion. Administration of high-dose DEHP significantly downregulated the expression of tight junction proteins and mucins. Histopathological analysis revealed goblet cell depletion and diminished mucin production. The results suggest that DEHP exacerbated food allergy through a multifactorial mechanism involving intestinal barrier dysfunction and immune dysregulation. This study establishes a critical association between oral DEHP exposure and food allergy pathogenesis, providing insights into the interplay of environmental pollutants, intestinal immunity, and food allergy manifestation.

Spleen-Heart Cross-Talk Through CD23-Mediated Signal Promotes Cardiac Remodeling

BACKGROUND

Elevated levels of IgE are implicated in pathological cardiac remodeling. However, the origin of IgE remains unknown. In the current study, we aim to explore the source of IgE and the mechanisms underlying IgE production in the context of pathological cardiac remodeling.

METHODS

Flow cytometry was used to assess the changes of IgE-producing B cells in different organs/tissues, including the spleen, lymph nodes, bone marrow, peripheral blood, vasculature, and heart, in mice with cardiac remodeling induced by transverse aortic constriction (TAC). The role of IgE low-affinity receptor FcεRII (also named CD23) in IgE-producing B cells during cardiac remodeling was evaluated in mice with loss-of-CD23 or gain-of-CD23. The therapeutic potential of the CD23-neutralizing antibody was evaluated. The factors involved in organ cross-talk, which regulate IgE production, were identified and validated both in vitro and in vivo.

RESULTS

We found that splenic IgE-producing cells were significantly elevated in the TAC mice. CD23, as a negative regulator of IgE production, was decreased in splenic B cells of TAC mice. Global knockout of CD23 in mice aggravated TAC-induced IgE synthesis and cardiac remodeling in vivo. In contrast, global or B-cell-specific CD23 overexpression in mice reduced IgE synthesis and alleviated TAC-induced cardiac remodeling. Mechanistically, CD23 was cleaved by ADAM10 (A disintegrin and metalloproteinase domain 10) in the spleen. Screening assay with data-independent acquisition mass spectrometry-based proteomics and ELISA identified Ltf (lactotransferrin), released from the heart shortly after TAC stimulation, as a contributor to ADAM10 upregulation through binding to Ltf receptor Ncl (nucleolin). Meanwhile, Ltf administration promoted IgE elevation, accompanied by increased ADAM10 expression and decreased CD23 expression in vitro and in vivo. Furthermore, the plasma Ltf levels were positively correlated with TAC-induced cardiac remodeling, serum IgE, and sCD23 (soluble CD23). Consistently, Ltf levels were elevated in patients with heart failure with reduced ejection fraction and also positively correlated with serum IgE and sCD23.

CONCLUSIONS

Our findings indicate a critical role of the Ltf-ADAM10-CD23 axis in regulating IgE production through cross-talk between the heart and spleen. The Ltf-ADAM10-CD23 axis may represent new molecular targets for IgE-mediated pathological cardiac remodeling.

Boosting Immunity Through Nutrition and Gut Health: A Narrative Review on Managing Allergies and Multimorbidity

The increasing global burden of allergic diseases and multimorbidity underscores the urgent need for innovative strategies to strengthen immune health. This review explores the complex relationships among nutrition, gut microbiota, immune regulation, allergic diseases, and multimorbidity. It highlights how targeted nutritional and microbial interventions may influence disease outcomes. Dietary components and microbial metabolites dynamically modulated immune function, highlighting the critical role of the gut-immune-metabolism axis in disease pathogenesis and management. Personalized nutrition, guided by advances in diagnostics such as component-resolved diagnostics, basophil activation tests, and epigenetic biomarkers, allows for precise dietary interventions tailored to individual allergy phenotypes and multimorbidity profiles. The Mediterranean diet, breastfeeding, and microbiota-targeted therapies have emerged as effective strategies to enhance immune resilience, reduce inflammation, and manage allergic reactions. Technological advancements, including artificial intelligence-driven dietary assessments, wearable devices, and mobile applications, have further revolutionized personalized dietary management, enabling real-time, precise nutritional monitoring and intervention. Despite these advances, challenges in implementing personalized nutrition persist, including variability in dietary patterns, cultural and socioeconomic factors, and accessibility concerns. Future research should focus on long-term interventional and longitudinal studies to validate precision nutrition strategies and enhance clinical applicability. This integrative approach, combining nutrition, microbiome science, technology, and personalized healthcare, holds substantial promises for sustainable disease prevention and enhanced immune resilience across diverse populations.

Effects of fermented dried brewer's grain on performance, carcass characteristics, morphology of ileum and blood parameters in broiler chickens

This experiment investigated the effects of fermentation on the chemical composition of dried brewer's grain (DBG) and its inclusion in broiler diets on performance, carcass traits, intestinal histology, and blood proteins. The DBG was fermented for 21 days using Bacillus subtilis and Aspergillus oryzae. A total of 360 male broilers (Ross 308) were fed with 10 % or 20 % DBG or fermented DBG (FDBG) for 42 days. Results revealed that fermentation could reduce crude fiber, pH, nitrogen-free extract, neutral detergent fiber, acid detergent fiber, and total bacterial count whereas it increased Lactobacillus count as well as fat, ash, calcium, and phosphorus contents (P<0.01). Broilers fed 10 % FDBG exhibited a similar performance to the control group. Serum levels of total protein and globulin were significantly higher in broilers that received 10 % FDBG compared to the control (P<0.01). However, feeding broilers with 20 % DBG or 20 % FDBG reduced weight gain and worsened the feed conversion ratio (P < 0.001). Moreover, broilers that received 20 % DBG had a shorter ileal villus height compared to the control group (P=0.034). These findings suggest that microbial fermentation could improve the nutritional quality of DBG, and the fermented product (FDBG) could be included in broiler diets up to 10 % without impacting performance.

Single-cell RNA sequencing reveals immunological link between house dust mite allergy and childhood asthma

Allergic asthma in children is typically associated with house dust mites (HDM) as the key allergen. Nevertheless, the diagnostic rate remains below 60% due to the absence of specific symptoms and diagnostic markers, which hinders the implementation of targeted personalized therapies. This study investigates immunological features of asthma with house dust mite (HDM) sensitisation in children, aiming to uncover diagnostic markers at single-cell resolution. The cohort comprised 8 children with physician-diagnosed asthma (age range: 4-11 years), stratified into groups based on HDM sensitization status. Single-cell RNA sequencing of peripheral blood mononuclear cells (PBMCs) was conducted, employing Seurat for cell identification and differential gene expression analysis. Enrichment analyses and LASSO regression identified signature genes related to cellular origin, with protein-protein interaction networks elucidating cellular communication differences between groups. A total of 11 distinct cell types were identified, with classical monocytes and monocytes being the predominant cell types that differentiated the two groups. Among these, 12 genes were up-regulated, and 40 down-regulated, mainly involving MHC-II complex and antigen presentation pathways, as validated by Gene Ontology and Gene Set Enrichment Analysis. The machine learning model accurately predicted cellular groupings, evidenced by an area under the curve of 0.83. Enhanced communication signals in HDM allergy cases involved monocytes, contrasting with reduced interactions in naive CD8 + cells. HLA-DR and HLA-DP were identified as the primary hallmark receptors, and the innate immunity differences with non-dust mite allergic asthma were characterized by 18 genes including top candidates MT-ND4 and RPS3A. Individuals with HDM-sensitized asthma exhibited altered expression of MHC-II complex genes in their PBMCs and distinct gene expression patterns in antigen-presenting cells, highlighting the critical role of HLA-DR and HLA-DP in the HDM allergen presentation.

Non-allergenic mixed T cell epitope peptides for preventing Scy p 9 allergic reactions

Filamin c is an allergen with strong IgE-binding activity of Scylla paramamosain (named Scy p 9). In this study, the T cell epitopes of Scy p 9 were identified using the CD4+T lymphocyte proliferation assay in the mononuclear cells of the spleen allergic mice. Nine of the thirteen T cell epitope peptides that have been found have the ability to trigger the production of the Th1 cytokine (IFN-γ) and TGF-β. Meanwhile, the findings of the inhibitory Dot blot and basophil activation test of crab allergy patients showed that the mixed nine T cell epitope peptides lacked IgE-binding activity and was unable to stimulate the expression of CD63 and CD203c on the surface of basophils. Non-allergenic mixed T cell epitope peptides (NAMTEP) demonstrate the potential for preventing Scy p 9 allergies. According to the evaluation of the preventive effect of Scy p 9 allergy mouse model, mice challenged with oral administration of Scy p 9 after early injection of NAMTEP did not show any allergic symptoms. NAMTEP inhibited IgE generation and Th2 immune response, preventing Scy p 9 allergy reactions in mice. These results would provide a theoretical foundation for the specific prevention of allergens in crustacean aquatic products.

DNA-Programmed Reaction to Evaluate Specific IgE for Allergy Point-of-Care Testing

A DNA-programmed reaction to evaluate non-nucleic acids inputs with computation speed (≈30 min) and sensitivity (sub-picomolar) suitable for analyzing physiologically relevant biomarkers in a one-pot format and point-of-care testing setting is reported. Specifically, a DNA programme based on the proximity-activation exponential amplification reaction (PEAR) is designed to evaluate specific IgE (sIgE) against Der p 2 implicated in dust mite allergy which affects millions worldwide. In this work, we tailored the molecular components of the input-to-oligo barcode conversion module as an AND gate to detect inputs with binding specificity to Der p 2 antigen and is of an IgE isotype. In addition, an in situ biotinylation method is developed to generate amplified oligo barcodes amendable for direct visualization on a lateral flow format. As a proof-of-concept demonstration of its potential clinical utility, 21 clinical samples are evaluated by the as-developed sIgE PEAR programme using the dual readout modality of real-time fluorescence measurement for precise input quantification and simple lateral flow yes/no answer.

Associations of multiple metals exposure with immunoglobulin levels in pregnant women: Hangzhou Birth Cohort Study

Metal may affect maternal immune function, but few epidemiological studies have reported the associations between multiple-metal exposure and maternal immunoglobulin (Ig) levels. Based on the Hangzhou Birth Cohort Study, 1059 participants were included, and eleven metals in whole blood samples and serum IgA, IgG, IgE and IgM levels were measured. Linear regression, quantile-based g-computation (QGC), and Bayesian kernel machine regression (BKMR) models were used to evaluate the associations. Compared with the first tertile of metal levels, arsenic (As) was negatively associated with IgE (β = -0.25, 95% confidence interval (CI) = -0.48 to -0.02). Moreover, significant associations of manganese (Mn) with IgA, IgG and IgM were demonstrated (β = 0.10, 95% CI = 0.04 to 0.18; β = 0.07, 95% CI = 0.03 to 0.12; β = 0.10, 95% CI = 0.03 to 0.18, respectively). Cadmium (Cd) were associated with higher levels of IgM. QGC models showed the positive association of the metal mixtures with IgA and IgG, with Mn playing a major role. Mn and Cd had positive contributions to IgM, while As had negative contributions to IgE. In the BKMR models, the latent continuous outcomes of IgA and IgG showed a significant increase when all the metals were at their 60th percentile or above compared to those at their 50th percentile. Therefore, exposure to metals was associated with maternal Igs, and mainly showed that Mn was associated with increased levels of IgA, IgG and IgM, and As was associated with low IgE levels.

The reduction effect on sensitization of sesame protein Ses i 3 of ultrasound-assisted glycation treatment through modulation of T cell differentiation

This study aimed to investigate the potential reduction on the sensitization of sesame protein Ses i 3 through ultrasound-assisted glycation. Ses i 3 was extracted and purified using an immunoaffinity column, and the allergenicity changes of Ses i 3 were assessed by a comprehensive strategy, and T cell polarization was also assessed in vivo. Results showed ultrasound-assisted glycation treated Ses i 3 was more easily digestible; and the cell degranulation model showed the histamine, tryptase, and β-hexosaminidase induced by ultrasound-assisted glycation treatment were significantly decreased; besides, the serological results demonstrated that a notable decrease in the binding ability of immunoglobulin E (IgE) and IgG; finally, a BALB/c mice model demonstrated an alleviation of allergic responses induced by ultrasonic-assisted glycation treatment. Meanwhile, the results in vivo also found that ultrasonic-assisted glycation treated Ses i 3 induced enhanced Helper T cell (TH) 1 cell differentiation while weakening TH2 cell differentiation, promoting TH1/TH2 balance polarization. Additionally, it induced stronger regulatory T (Treg) cell differentiation, and suppressed TH17 cell differentiation, promoting Treg/TH17 balance. This study demonstrated that the sensitization of Ses i 3 was reduced after ultrasonic-assisted glycation treatment, and this effect was associated with the modulation of T cell differentiation.

Structural and Functional Insights Into IgE Receptor Interactions and Disruptive Inhibition

Immunoglobulin E (IgE) plays a critical role in host defense against parasites and venoms but is also best known for its central involvement in allergic reactions. Through interactions with its high- and low-affinity receptors, FcεRI and CD23, respectively, IgE sensitizes mast cells and basophils, drives antigen presentation, regulates antibody production, and overall amplifies type 2 immunity. The unique conformational flexibility of IgE, particularly within its Cε2-Cε4 domains of the Fc-region, has emerged as a key determinant of receptor specificity and function. Structural studies have revealed that IgE adopts distinct open and closed conformations that selectively enable FcεRI or CD23 binding. These insights have reshaped our understanding of receptor engagement and laid the foundation for therapeutic targeting approaches of IgE:receptor interactions to treat allergies. Initial anti-IgE biologics, such as omalizumab, were developed to neutralize free IgE in circulation and prevent receptor binding. While clinically successful, this approach has limitations, such as the inefficient targeting of receptor-bound IgE and the requirement for prolonged and frequent injections to achieve therapeutic benefit. Recent advances have led to the development of a new class of anti-IgE molecules termed "disruptive" IgE inhibitors that actively disassemble preformed IgE:FcεRI complexes. By exploiting conformational dynamics, creating steric interference, or allosteric mechanisms, these molecules, in addition to their neutralizing capacity, enable rapid active desensitization of allergic effector cells. In this review, we highlight how an improved structural and mechanistic understanding of IgE and its receptors has guided the design of such next-generation anti-IgE molecules. Such multifunctional biologics might offer faster onset, broader activity, and potential use in acute allergic situations, setting the stage for a new era in IgE-targeted therapy.

Allergen Immunotherapy: Pitfalls, Perks and Unexpected Allies

Allergen immunotherapy (AIT) is a well-established treatment aimed at reducing allergen sensitivity by gradually exposing the immune system to increasing doses of allergens. This promotes desensitization and immune tolerance through multiple mechanisms. AIT offers long-term immune modulation and is considered a potentially curative certain forms of allergic diseases. Altered antibody responses is a key mechanism of AIT in the production of allergen-specific IgG4 antibodies, which act as blocking antibodies to prevent allergen binding to IgE on mast cells (MCs) and basophils. However, IgG4 responses are sometimes ineffective due to variations in antibody affinity and epitope targeting. Reverse class switching from IgE to IgG4 and selective depletion of IgE-producing B cells represent potential strategies to improve AIT efficacy. Tregs play a central role in AIT by suppressing Th2-driven allergic responses and promoting immune tolerance through anti-inflammatory cytokines interleukin (IL)-10 and transforming growth factor (TGF)-β. However, genetic and environmental factors may impair Treg function, leading to AIT failure. AIT reduces MC and basophil activation, leading to long-term suppression of allergic inflammation. It modulates IgE-FcεRI interactions and cytokine signaling pathways, but in some cases, anaphylactic reactions or resistance to MC desensitization may occur. Discussion and conclusions: While AIT is a highly effective allergy treatment, variability in immune responses can impact its success. Advances in biologic therapies offer potential synergies with AIT. Understanding these interactions will help refine AIT strategies and improve patient outcomes.

The combination of allergen immunotherapy and biologics for inhalant allergies: Exploring the synergy

The development of monoclonal antibodies that selectively target IgE and type 2 immunity has opened new possibilities in the treatment of allergies. Although they have been used mainly as single therapies found to have efficacy in the management of asthma and other T2-mediated diseases, there is a growing interest in using these monoclonal antibodies in combination with allergen immunotherapy (AIT). AIT has transformed the treatment of allergic diseases by aiming to modify the underlying immune response to allergens rather than just providing temporary symptom relief. Despite the proven efficacy and safety of AIT, unmet needs call for further research and innovation. Combination strategies involving biologics and AIT exhibit potential in improving short-term efficacy, reducing adverse events, and increasing immunologic tolerance. Anti-IgE emerges as the most promising therapeutic strategy, not only enhancing AIT's safety and tolerability but also providing additional evidence of efficacy compared with AIT alone. Anti-interleukin-4 receptor offers a reduction in adverse effects and an improved immunologic profile when combined with AIT; however, its impact on short-term efficacy seems limited. The combination of cat dander subcutaneous immunotherapy with anti-thymic stromal lymphopoietin was synergistic with enhanced efficacy and altered immune responses that persisted for 1 year after discontinuation compared with AIT alone. Long-term studies are needed to evaluate the sustained benefits and safety profiles of combination strategies.

A Single Multiplex CytoBas Assay Incorporating Eight Major Components for Accurate Detection of Allergen Sensitization in Asthma and Allergic Rhinitis

BACKGROUND

Allergic rhinitis and asthma can be triggered by a variety of aeroallergens, including house dust mites (HDM), tree and grass pollen, and household pets. Identification of the relevant allergen is critical for lifestyle changes and treatments, including allergen immunotherapy. We here assessed the diagnostic performance and clinical utility of a single flow cytometry staining of basophils with major aeroallergen components (AeroDiff CytoBas).

METHODS

In 156 atopic patients with allergic rhinitis/asthma and 21 non-atopic individuals, allergen-specific IgE levels were determined by ImmunoCAP, and component-specific IgE by ELISA. PBMCs were analyzed by flow cytometry with basophil markers and eight fluorochrome-conjugated allergen component tetramers.

RESULTS

Patients were stratified for sensitization to each of the four allergens. Allergen-component staining in a single multiplex CytoBas assay and component-specific IgE serology performed similarly for Der p 2, Lol p 1, Fel d 1, and Can f 1 (ROC AUC: 0.76-0.97 vs. 0.73-0.93). CytoBas had greater diagnostic accuracy than component-specific IgE serology (p < 0.001) for HDM sensitization using Der f 1 or Der p 1, and grass pollen using Lol p 5 or Phl p 1. Furthermore, the combined evaluation of Der p 1 and Der p 2 with CytoBas was 96.3% sensitive and 90.7% specific for HDM sensitization. The combined evaluation of Lol p 1 and Lol p 5 achieved 95.4% sensitivity and 96.4% specificity for ryegrass pollen sensitization.

CONCLUSION

AeroDiff CytoBas has similar to superior diagnostic accuracy compared to singleplex IgE serology, with the additional advantage of a single assay to evaluate multiple allergens. This enables precise and efficient component-resolved diagnosis of aeroallergen sensitization to guide personalized treatment for patients with allergic rhinitis and/or asthma.

Maternal obesity associates with altered humoral immunity in blood and colostrum

Maternal obesity is a condition with increasing prevalence worldwide, that correlates with negative infant outcomes. Here we performed an observational cross-sectional study, where peripheral blood and colostrum samples from 37 mothers with BMI between 18.5-25 or > 30 kg/m2 (21 and 16 mothers, respectively) were collected 24-48 h postpartum. B lymphocyte subpopulations were investigated using flow cytometry. IgG, IgA, and IgM concentrations, and antibody production from colostrum-resident B cells were quantified. Overall, naïve B lymphocytes were the most abundant subtype in peripheral blood, while CD27-IgD- double-negative B cells were the most frequent in colostrum. The colostrum from mothers with BMI > 30 kg/m2 contained significantly more IgG-secreting colostrum-resident B cells, more total IgG, and less total IgA. Mothers with BMI > 30 kg/m2 who had been vaccinated with the Pfizer BioNTech bivalent vaccine during the third trimester of pregnancy (n = 8) did not show higher IgA or IgG antibody responses against SARS-CoV-2 RBD in either tissue types compared to unvaccinated mothers, contrasting with mother of BMI between 18.5-25 kg/m2 (n = 7). This is the first characterization of B lymphocyte subpopulations and antibodies in the colostrum of mothers with obesity. This work uncovers maternal obesity as a possible modifier of humoral immune components in colostrum.

The Direct and Indirect Role of IgE on Airway Epithelium in Asthma

Asthma is a chronic airway inflammatory disorder, affecting over 350 million people worldwide, with allergic asthma being the most common form of the disease. Allergic asthma is characterized by a type 2 (T2) inflammatory response triggered by numerous allergens beginning in the airway epithelium, which acts as a physical barrier to allergens as well as other external irritants including infectious agents, and atmospheric pollutants. T2 inflammation is propagated by several key cell types including T helper 2 (Th2) cells, eosinophils, mast cells, and B cells. Immunoglobulin E (IgE), produced by B cells, is a key molecule in allergic airway disease and plays an important role in T2 inflammation, as well as being central to remodeling processes within the airway epithelium. Blocking IgE with omalizumab has been shown to be efficacious in treating allergic asthma however, the role of IgE on airway epithelial cells is less communicated. Developing a deeper explanation of the complex network of interactions between IgE and the airway epithelium will facilitate an improved understanding of asthma pathophysiology. This review discusses the indirect and direct roles of IgE on airway epithelial cells, with a focus on allergic asthma disease.

Allergy Treatment: A Comprehensive Review of Nanoparticle-based Allergen Immunotherapy

Allergic disorders rising in prevalence globally, affecting a substantial proportion of individuals in industrialized nations. The imbalance in the immune system, characterized by elevated allergen-specific T helper 2 (Th2) cells and immunoglobulin E (IgE) antibodies, is a key factor in allergy development. Allergen-specific immunotherapy (AIT) is the only treatment capable of alleviating allergic symptoms, preventing new sensitizations, and reducing asthma risk in allergic rhinitis patients. Traditional AIT, however, faces challenges such as frequent administration, adverse effects, and inconsistent patient outcomes. Nanoparticle-based approaches have emerged as a promising strategy to enhance AIT. This review explores the utilization of nanoparticles in AIT, highlighting their ability to interact with the immune system and improve therapeutic outcomes. Various types of nanoparticles, including polyesters, polysaccharide polymers, liposomes, protamine-based nanoparticles (NPs), and polyanhydrides, have been employed as adjuvants or carriers to enhance AIT's efficacy and safety. Nanoparticles offer advantages such as allergen protection, improved immune response modulation, targeted cell delivery, and reduced side effects. This review provides an overview of the current landscape of nanoparticle-based allergen immunotherapy, discussing its potential to revolutionize allergy treatment compared to traditional immunotherapy.

Pharmacology and safety of TAS5315, a Bruton tyrosine kinase inhibitor, in healthy volunteers: First-in-human, randomized, ascending-dose studies

AIM

TAS5315 is a Bruton tyrosine kinase (Btk) inhibitor in development for autoimmune and allergic diseases, including rheumatoid arthritis (RA) and chronic spontaneous urticaria (CSU). Two clinical studies evaluated the pharmacology and safety of single and multiple oral doses of TAS5315.

METHODS

Two phase 1 studies (single ascending-dose [SAD] and multiple ascending-dose [MAD]) assessed the pharmacokinetics (including effect of food), pharmacodynamics (Btk occupancy, inhibition of basophil activation) and safety of TAS5315 (up to 8 mg/day) in healthy males.

RESULTS

TAS5315 showed linear pharmacokinetics over a 0.01-8 mg dose range; maximum plasma concentration and area under the plasma concentration-time curve were reduced by ~40% by food. TAS5315 had dose dependent effects on Btk and basophil activation. In the SAD study, doses ≥2 mg resulted in mean Btk occupancy of almost 100% at 2 and 6 h, and >80% at 24 h, post-administration. TAS5315 1-8 mg/day inhibited basophil activation (mean change from baseline -55% to -89%). TAS5315 was generally tolerable. Although it dose-dependently reduced platelet aggregation (over 2-8 mg in both studies) and prolonged bleeding time (1-8 mg in the MAD study), no relationship between these effects and clinical symptoms was observed. All adverse drug reactions were mild and resolved without treatment; no noteworthy safety concerns were observed in either study.

CONCLUSION

These data indicate TAS5315 has potential as a novel therapeutic for immunological diseases associated with aberrant Btk signalling, including RA and CSU. Further evaluation of TAS5315 is warranted.

Allergen-Specific Immunotherapy and Trained Immunity

The high prevalence of allergic diseases reached over the last years is attributed to the complex interplay of genetic factors, lifestyle changes, and environmental exposome. Allergen-specific immunotherapy (AIT) is the single therapeutic strategy for allergic diseases with the potential capacity to modify the course of the disease. Our knowledge of the mechanisms involved in allergy and successful AIT has significantly improved. Recent findings indicate that long-term allergen tolerance upon AIT discontinuation not only relies on the generation of proper adaptive immune responses by the generation of allergen-specific regulatory T and B cells enabling the induction of different isotypes of blocking antibodies but also relies on the restoration of proper innate immune responses. Trained immunity (TRIM) is the process by which innate immune cells acquire memory by mechanisms depending on metabolic and epigenetic reprogramming, thus conferring the host with increased broad protection against infection. This concept was initially explored for infectious diseases, as well as for vaccination against infections, but compelling experimental evidence suggests that TRIM might also play a role in allergy and AIT. Hyperinflammatory innate immune responses in early life, likely due to TRIM maladaptations, lead to aberrant type 2 inflammation-enhancing allergy. However, exposure to farming environments and specific microbes prevents recurrent infections and allergy development, likely due to mechanisms partially depending on TRIM. TRIM-based vaccines and next-generation AIT vaccines inducing metabolic and epigenetic reprogramming in innate immune cells and their precursors have shown protective antiallergic effects. A better understanding of the factors involved in early-life TRIM mechanisms in the context of allergy and the identification and characterization of novel tolerance inducers might well enable the design of alternative TRIM-based allergen vaccines for allergic diseases.

Pathogenic and Nonpathogenic Antibody Responses in Allergic Diseases

Allergen-specific antibodies, particularly of the IgE class, are a hallmark of many allergic diseases. Yet paradoxically, (1) a proportion of healthy individuals possess allergen-specific IgE without clinical signs of allergy; (2) some, but not all, allergic individuals develop a more severe disease over time or fail to respond to allergen-specific immunotherapy; and (3) allergen-specific IgG antibodies can inhibit IgE-mediated responses but they can also induce allergic reactions. In this review, we discuss the occurrence of and transition between nonpathogenic and pathogenic allergen-specific antibody responses in the light of a two-stage model. We recapitulate different factors and scenarios that may induce different inflammatory conditions and qualitatively distinct allergen-specific T- and B-cell responses, influencing IgE origins and affinities, IgE/IgG(4) ratios, IgG effector functions, antibody glycosylation patterns, Fc and glycan-binding receptor expression and involvement, and ultimately their propensity to elicit allergic responses. Differences in these antibody characteristics may determine the onset of symptomatic allergy and the severity or remission of the disease.

Interactions between protein Z and lycopene: A win-win scenario for both security and stability

Malt protein Z (PZ), the main albumin in malt endosperm, exhibits trypsin inhibitory activity and has the ability to bind fat-soluble active molecules. However, its potential utilization as a food ingredient necessitates an evaluation of its allergenicity. Lycopene has many functional activities, such as antioxidant and treatment or alleviation of various diseases, but its tendency to degrade easily hinders its effective utilization. Therefore, this paper investigates the allergenicity of PZ and provides a win-win scenario that PZ interacts with lycopene. PZ interacts with lycopene through non-covalent interactions with a ratio of 4.07 ± 0.20, leading to the formation of homogenous particles with an increased absolute zeta potential, from -7.3 ± 0.2 to -20.0 ± 0.6. Unsurprisingly, the presence of lycopene alleviates the allergenicity of PZ by decreasing the IgE, mMcp-1 and vascular permeability, such as the plasma mMcp-1 decreased from 245.0 ± 5.2 ng/mL for the PZ group to 217.8 ± 4.1 ng/mL for the PZ-LYC group. To uncover the potential mechanism, the linear antigenic epitopes of PZ by ABCpred were predicted, which are almost the potential binding site of lycopene at PZ. On the other hand, PZ improved the storage stability of lycopene. The addition of PZ increased lycopene retention in solution from 14.9 ± 2.7 % to 65.5 ± 2.8 % over 10 days at room temperature with light exposure. These results provide foundations for PZ utilization concerning security, and give ways to protect bioactive molecules.

Zyxin-a novel detrimental target, is inhibited by Saikosaponin A during allergic asthma

BACKGROUND

Allergic asthma is a heterogeneous disease involving numerous inflammatory cells. Mast cell (MC) plays a key role during allergic asthma. Saikosaponin A (SSA) inhibits MC activation and ameliorates allergic asthma, however, its underlying mechanism remains unclear. This study aims to identify SSA-binding proteins and reveal their functions.

METHODS

C57BL/6J mice were used to establish allergic asthma models to evaluate therapeutic effect of SSA. Protein microarray, RNA-seq, surface plasmon resonance (SPR), and pull-down assay were used to explore and validate the binding proteins of SSA. The functions of Zyxin were explored by knockdown and overexpression in LAD2. Zyxin knockout mice were constructed to investigate the role of Zyxin in allergic asthma.

RESULTS

SSA alleviates allergic asthma and inhibits MC activation. Zyxin was confirmed as a binding protein of SSA. In vitro experiments proved the crucial role of Zyxin in mast cell exocytosis. Zyxin Ser142/143 is phosphorylated during MC activation, which can be inhibited by SSA. In vivo studies showed that Zyxin expression in MC has detrimental effects, while its deficiency ameliorates allergic asthma.

CONCLUSION

Our results verified the detrimental effect of Zyxin in allergic asthma for the first time. We also innovatively demonstrated that SSA exerts inhibitory effects on MC activation and allergic asthma by directly binding to and inhibiting Zyxin phosphorylation.

Asthma identified as a major risk factor for recurrent respiratory tract infections in children: a meta-analysis of 29 studies

BACKGROUND

Recurrent respiratory tract infections (RRTIs) in children represent a significant clinical challenge. Although some studies have identified potential risk factors, a comprehensive and systematic overview is lacking.

OBJECTIVE

This analysis is carried out to provide more advanced evidence to guide future prevention and health care.

METHODS

This study (PROSPERO: CRD42024576464) was conducted in accordance with PRISMA guidelines. PubMed, Embase, Web of Science, and the Cochrane Library were searched for relevant studies published in English. Subgroup analysis, sensitivity analysis, and publication bias assessments were performed. Data analysis was conducted using Stata 17, and GRADE was employed to assess the quality of evidence. The risk factors identified in the positive results were discussed qualitatively.

RESULTS

A total of 29 studies covering 639,078 children were included. Some risk factors: asthma (OR = 3.08, 2.06-4.62), breastfeeding <6 months (OR = 1.26, 1.04-1.52), DCC: day care center (OR = 1.50, 1.16-1.93), have siblings (OR = 1.26, 1.00-1.59), ETS: Environmental tobacco smoke (OR = 1.13, 1.00-1.27), snoring (OR = 1.49, 1.16-1.93) got positive result.

CONCLUSION

This analysis identifies several key risk factors for RRTIs in children, providing enhanced evidence for prevention and management strategies. In particular, asthma warrants closer attention, given its strong association with respiratory infections in pediatrics.

Progressively differentiated TFH13 cells are stabilized by JunB to mediate allergen germinal center responses

Allergic diseases are common and affect a large proportion of the population. Interleukin-13 (IL-13)-expressing follicular helper T (TFH13) cells are a newly identified population of TFH cells that have been associated with high-affinity IgE responses. However, the origins, developmental signals, transcriptional programming and precise functions of TFH13 cells are unknown. Here, we examined the developmental signals for TFH13 cells and found a direct and progressive differentiation pathway marked by the production of IL-21. These two pathways differed in kinetics and extrinsic requirements. However, both pathways converged, forming transcriptionally similar TFH13 cells that express the transcription factor JunB as a critical stabilizing factor. Using an intersectional genetics-based TFH13-diphtheria toxin receptor model to perturb these cells, we found that TFH13 cells were essential to drive broad germinal center responses and allergen-specific IgG and IgE. Moreover, we found that IL-21 is a broad positive regulator of allergen germinal center B cells and synergizes with IL-13 produced by TFH13 cells to amplify allergic responses. Thus, TFH13 cells orchestrate multiple features of allergic inflammation.

Ultrasound assisted glycation decreased the potential allergenicity through changing epitope and structures of Ses i 3

Ses i 3 is one of the major allergens in sesame, and this study aimed to investigate the effect and mechanism of ultrasound-assisted glycation on the potential allergenicity of Ses i 3. Results showed that the IgG and IgE binding of Ses i 3 was significantly reduced after ultrasound-assisted glycation, and the KU812 cell degranulation results showed a significantly decrease of degranulation in the ultrasound-assisted glycation group, suggesting a reduction in the allergenicity of Ses i 3. Subsequently, results from the contents of free amino groups and available lysine showed that ultrasound pretreatment facilitated the glycation reaction. Moreover, five linear epitopes were predicted, with S-5 (AA 571-582) being identified as the effective B cell linear epitope through solid-phase peptide synthesis and serological experiments. Its spatial location was also determined using a AlphaFold 3 model. Besides, inhibited competitive ELISA results indicated that the addition of inhibitor (S-5) didn't reduce the IgE binding of Ses i 3 in the ultrasound-assisted glycation group, suggesting that ultrasound-assisted glycation might have masked or destroyed the S-5 epitope. Ultraviolet (UV) spectra and intrinsic fluorescence emission spectrum results revealed a blue shift in the maximum absorption peaks, along with a significant reduction in surface hydrophobicity, indicating substantial changes in both secondary and tertiary structures. In conclusion, this study demonstrated that ultrasound-assisted glycation effectively reduced the allergenicity of Ses i 3, with the reduction being closely linked to changes in the S-5 epitope and structures. These findings will provide a basis for the development of hypoallergenic sesame products.

Effects of partial silage replacement with corn stover pellets on the rumen microbiota and serum metabolome of breeding cows

Introduction

Straw pellet ration replacing part of silage is of great significance for farmers to save farming costs and solve the lack of feed resources. A comprehensive analysis of rumen microbial and serum metabolite compositions is conducted to promote the development of the modern breeding cows-feeding industry.

Methods

In this study, 18 healthy 2-year-old Simmental breeding cows weighing 550 ± 20 kg were selected and randomly divided into two groups. They were fed under the same feeding conditions for 70 days, of which 8 in the control (CON) group were fed 65% roughage (100% silage) + 35% concentrate, and 10 in the treatment (TRT) group were fed 65% roughage (50% corn stover pellets +50% silage) + 35% concentrate, and milk quality, serum immunity indexes, serum metabolomes, rumen fermentation parameters, rumen Microorganisms.

Results

The results showed that there was no significant difference in production performance between the two groups of breeding cows fed hay and Corn stover pellet feed (p < 0.05); Immunoglobulin A (IgA) was significantly higher in TRT compared to CON (p < 0.05), and there was no significant difference in Immunoglobulin G (IgG) and Immunoglobulin M (IgM) between the two groups (p > 0.05); a total of 92 differential metabolites were screened out in the serum metabolomics analysis, among them, L-valine, L-leucine, L-arginine, L-cysteine, L-tyrosine, and L-tryptophan were up-regulated; In rumen fermentation parameters there was no significant difference between CON and TRT in rumen pH, rumen ammonia nitrogen (NH3-N) content, rumen Acetic/Propionic concentration (p > 0.05), and the concentration of Acetic, Propionic, butyric and Total volatile fatty acids (TVFA) in CON was significantly lower than that in TRT (p < 0.05). Among the rumen microorganisms, the dominant groups were Thick-walled Firmicutes, Bacteroidota, Prevotella and Ruminalococcus. In the correlation analysis between rumen fermentation parameters and rumen microorganisms, Propionic and TVFA showed a significant positive correlation with Prevotella (p < 0.05), butyric showed a highly significant positive correlation with Prevotella (p < 0.01), and propionic butyric, and TVFA showed a positive correlation with Bacteroides (p < 0.05); L-cysteine was significantly positively correlated with Prevotella and Anaeroplasma (p < 0.05) and Eubaterium in rumen microbial-serum metabolite correlation analysis (p < 0.01).

Conclusion

The microbial and metabolomic analyses provide us with essential data support to further provide a scientific basis for breeding cows feeding through the feeding pattern of straw pellets instead of silage, which will help breeding cows farming in future research.

Probiotics and gut microbiota modulation: implications for skin health and disease management

The gut microbiota, consisting of a varied population of microorganisms in the digestive tract, is essential for sustaining overall human health, encompassing skin health. This review explored the intricate relationship between gut microbiota and various skin disorders, investigating the pathways through which gut dysbiosis may have impacted the development and progression of these conditions. We focused on the impact of gut microbiota on atopic dermatitis, psoriasis, acne vulgaris, acne rosacea, and melanoma. The review highlighted the potential of probiotics as a therapeutic strategy for modulating gut microbiota composition and, consequently, improving skin health. We discussed the evidence supporting the use of probiotics in managing these skin disorders and explored the mechanisms by which probiotics delivered their positive effects. Finally, we discussed the potential role of gut microbiota in other skin diseases, emphasizing the need for further research to unravel the complex interplay between the gut and the skin. Significant gaps remain in understanding the gut-skin axis, how microbial interactions contribute to skin disorders, and how to effectively manipulate the microbiome for therapeutic purposes. This review provided extensive research on the gut-skin axis, highlighting the promising prospects of modulating gut microbiota as a therapeutic strategy for various dermatological conditions.

Sensitization to common foods and early vascular aging: associations and the mitigating effects of health behaviors

BACKGROUND

Sensitization to common foods is typically considered clinically irrelevant in individuals without symptomatic food allergies. However, recent studies found an association between IgE specific to the mammalian oligosaccharide galactose-α-1,3-galactose and cardiovascular disease (CVD). The aims of this study are to determine whether common food sensitization is associated with early vascular aging (EVA) and to examine whether healthier lifestyle behaviors modifies the association in individuals without CVD.

METHODS

This was a cross-sectional, population-based study of 2788 American participants aged 30 years or older without cardiovascular disease. Total and specific IgE levels for common foods were measured. EVA was defined based on the 10th percentile of the difference between chronological age (CA) and vascular age (VA). Logistic regression models were employed to assess the associations between food sensitization and EVA, and whether healthy lifestyle modified the association. Poisson regression models, ordinal logistic regression models, and linear regressions were performed as sensitivity analysis.

RESULTS

Sensitization to at least one food allergen associated with an increased risk of EVA (odds ratio [OR] 1.91 [95% confidence interval (CI), 1.1 to 3.3]). Milk sensitization demonstrated the most robust association (OR 7.18, [95% CI, 2.5 to 20.62]). Additionally, moderate to vigorous activities (MVA) (OR 0.33 [95% CI, 0.11 to 0.97]) and sufficient sleep duration (OR, 0.21 [95% CI, 0.07 to 0.65]) mitigate the association between food sensitization and EVA. Similar results were presented in Poisson regression models, ordinal logistic regression models, and linear regressions.

CONCLUSIONS

The findings that common foods sensitization is independently associated with EVA, and that MVA and adequate sleep duration mitigate the association, have significant public health implications. Further research is needed to elucidate the mechanisms.

Modulation of NF-κB/Nrf2 signaling by nobiletin mitigates airway inflammation and oxidative stress in PM2.5-exposed asthmatic mice

Exposure to fine particulate matter (PM2.5) is a significant risk factor for asthma, promoting airway inflammation and oxidative stress. This study evaluates Nobiletin's (NOB) efficacy in mitigating airway inflammation and oxidative lung damage in asthma-induced mice exposed to PM2.5. Using an ovalbumin (OVA) plus PM2.5-induced asthma model in BALB/c mice, we investigated the therapeutic impacts of NOB compared to dexamethasone (DEX). NOB significantly moderated lung index values and inflammatory markers without affecting body weight. Notably, NOB enhanced Nrf2 expression and decreased NF-κB-p65, IKK, and Keap-1 levels, aligning with reductions in malondialdehyde (MDA) and reactive oxygen species (ROS) while increasing superoxide dismutase (SOD) and glutathione peroxidase (GPx) activities. These findings suggest that NOB can effectively reduce airway inflammation and oxidative lung damage by modulating the NF-κB/Nrf2 signaling pathways.

Six Injections of Modified Adjuvanted PQ Grass Is Effective and Well-Tolerated in a Pivotal Phase III Trial

BACKGROUND

PQ Grass 27600 SU (PQ Grass) cumulative dose is a pre-seasonal, six-injection, aluminium-free, modified subcutaneous immunotherapy product under development for the treatment of allergic rhinitis (AR). A pivotal Phase III randomised double-blind, placebo-controlled clinical trial was performed to evaluate the efficacy and safety of PQ Grass in subjects with seasonal AR.

METHODS

An adaptive group sequential trial PQGrass306 (G306) with one pre-defined interim analysis was designed, using 2 parallel groups applying a 1:1 active versus placebo randomisation of patients aged 18-65. The primary efficacy endpoint was the EAACI (European Academy of Allergy and Clinical Immunology) Combined Symptom and Medication Score (EAACI-CSMS0-6) averaged over the peak grass pollen season (GPS).

RESULTS

858 subjects were screened and 555 subjects were randomised. Based on the results of the pre-defined interim analysis, the trial was stopped for success showing superiority in favour of PQ Grass. The primary endpoint EAACI-CSMS0-6 (peak GPS) demonstrated a highly significant and clinically meaningful point difference of PQ Grass over placebo of -0.27 points (95% CI: -0.42 to -0.12), corresponding to a relative difference of -20.3% (p = 0.0005). Highly consistent and beneficial results were obtained for PQ Grass for all key secondary endpoints. Significant induction of blocking IgG4 and IgA antibody subclasses occurred. PQ Grass was well tolerated, and no unexpected safety signals occurred.

CONCLUSIONS

This pivotal Phase III trial demonstrated a significant and clinically meaningful effect on the primary endpoint as well as highly consistent secondary endpoint results and a supportive safety profile.

Full-Length Immune Repertoire Reconstruction and Profiling at the Transcriptome Level Using Long-Read Sequencing

BACKGROUND

Due to the diversity of the immune repertoire (IR), reconstructing full-length IR using traditional short-read sequencing has proven challenging.

METHODS

A full-length IR sequencing (FLIRseq) work flow was developed with linear rolling circle amplification and nanopore sequencing. Its accuracy and quantification ability were verified by plasmid mixtures and commercial B-cell receptor/T-cell receptor sequencing (BCR/TCR-seq) based on short reads. IRs in tissues and the peripheral blood from 8 patients with acute lymphoblastic leukemia, 3 patients with allergic diseases, 4 patients with psoriasis, and 5 patients with prostate cancer were analyzed using FLIRseq.

RESULTS

FLIRseq reads had lower mismatch rates and gap rates, and higher identify rates than nanopore reads (all P < 2.2 × -16). The relative quantification of components by FLIRseq was consistent with the actual quantification (P > 0.05). FLIRseq had superiority over BCR/TCR-seq, providing the long complementarity-determining region 3, B-cell isotype, and the rarely used V gene sequence. FLIRseq observed an increase in clonotype diversity (P < 0.05) and a decrease in the percentage of abnormal BCRs/TCRs in patients with leukemia in remission. For patients with allergic diseases or psoriasis, FLIRseq provided direct insights into V(D)J recombination and specific immunoglobulin classes. Compared with that in prostate cancer tissues, the full-length V segment of the biased T-cell receptor β chain from lymphocytes in psoriatic tissues showed a more consistent AlphaFold2-predicted protein structure (P < 0.05).

CONCLUSIONS

FLIRseq enables unbiased and comprehensive analyses of direct V(D)J recombination and immunoglobulin classes, thereby contributing to characterizing pathogenic mechanisms, monitoring minimal residual disease, and customizing adoptive cell therapy.

Molecular allergy diagnosis enabling personalized medicine

Allergic patients are characterized by complex and patient-specific IgE sensitization profiles to various allergens, which are accompanied by different phenotypes of allergic disease. Molecular allergy diagnosis establishes the patient's IgE reactivity profile at a molecular allergen level and has moved allergology into the era of precision medicine. Molecular allergology started in the late 1980s with the isolation of the first allergen-encoding DNA sequences. Already in 2002, the first allergen microarrays were developed for the assessment of complex IgE sensitization patterns. Recombinant allergens are used for a precise definition of personal IgE reactivity profiles, identification of genuine IgE sensitization to allergen sources for refined prescription of allergen-specific immunotherapy and allergen avoidance diagnosis of co- versus cross-sensitization, epidemiologic studies, and prediction of symptoms, phenotypes, and development of allergic disease. For example, molecular IgE sensitization patterns associated with more severe respiratory allergies, severe food allergy, and allergy to honeybee or vespids are already established. The implementation of molecular allergy diagnosis into daily clinical practice requires continuous medical education and training doctors in molecular allergy diagnosis, and may be facilitated by clinical decision support systems such as diagnostic algorithms that may take advantage of artificial intelligence.

Prediction, identification, and analysis of major B-cell linear epitopes of bomb m 6 from silkworm pupa

Bomb m 6 is one of the most representative allergens in silkworm pupae. The aim of the present study was to investigate the B-cell linear epitopes of Bomb m 6. Sequence propensity- and machine learning-based strategies were first used to predict 12 and 8 candidate epitopes, respectively. Then, 46 overlapping peptides [P1-P46; length, 15 amino acids (AAs); offset, 5 AAs] spanning the Bomb m 6 sequence were synthesized and tested for IgE/IgG reactivity by dot blotting. Seven IgE-binding epitopes and six IgG-binding epitopes were identified. AA61-80, AA136-150, and AA146-150 were identified as the shared dominant IgE/IgG-binding epitopes. The epitopes contain mainly α-helix and β-sheet structures and high proportions of hydrophobic AAs, and are distributed in charged regions. The major peptides of the epitopes were poorly resistant to simulated gastrointestinal fluid digestion. These findings provide a reference for the prevention of and immunotherapy for silkworm pupa allergy.

Comprehensive review of pollen-food allergy syndrome: Pathogenesis, epidemiology, and treatment approaches

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.

IL-10: the master immunomodulatory cytokine in allergen immunotherapy

INTRODUCTION

Allergen immunotherapy (AIT) is the only disease-modifying treatment for patients with IgE-mediated allergic diseases. Successful AIT can induce long-term immune tolerance to the common allergen, which provides clinical benefits for years after discontinuation. The cytokine interleukin (IL)-10, as a key anti-inflammatory mediator with strong immunoregulatory functions, has drawn increasing attention over the past decades.

AREAS COVERED

After an extensive search of PubMed, EMBASE, and Web of Science databases, covering articles published from 1989 to 2024, our review aims to emphasize the key common information from previous reviews on the crucial involvement of IL-10 in allergen immunotherapy (AIT) induced immunological tolerance. In this review, we discuss the regulation of IL-10 expression and the molecular pathways associated with IL-10 function. We also further summarize mechanisms of immune tolerance induced by AIT, especially the indispensable role of IL-10 in AIT.

EXPERT OPINION

IL-10 plays an indispensable role in immune tolerance induced by AIT. Understanding the importance of the role of IL-10 in AIT would help us comprehend the mechanisms thoroughly and develop targeted therapeutics for allergic diseases.

Reducing the solubility of the major birch pollen allergen Bet v 1 by particle-loading mitigates Th2 responses

BACKGROUND

Solubility is a common feature of allergens. However, the causative relationship between this protein-intrinsic feature and sensitization capacity of allergens is not fully understood. This study aimed to proof the concept of solubility as a protein intrinsic feature of allergens.

METHODS

The soluble birch pollen allergen Bet v 1 was covalently coupled to 1 μm silica particles. IgE-binding and -cross-linking capacity was assessed by inhibition ELISA and mediator release assay, respectively. Alterations in adjuvanticity by particle-loading were investigated by activation of dendritic cells, mast cells and the Toll-like receptor 4 pathway as well as by Th2 polarization in an IL-4 reporter mouse model. In BALB/c mice, particle-loaded and soluble Bet v 1 were compared in a model of allergic sensitization. Antigen uptake and presentation was analysed by restimulating human Bet v 1-specific T cell lines.

RESULTS

Covalent coupling of Bet v 1 to silica particles resulted in an insoluble antigen with retained IgE-binding and -cross-linking capacity and no increase in adjuvanticity. In vivo, particle-loaded Bet v 1 induced significantly lower Bet v 1-specific (s)IgE, whereas sIgG1 and sIgG2a levels remained unaffected. The ratio of Th2 to Th1 cells was significantly lower in mice sensitized with particle-loaded Bet v 1. Particle-loading of Bet v 1 resulted in a 24-fold higher T cell activation capacity in Bet v 1-specific T cell lines, indicating more efficient uptake and presentation than of soluble Bet v 1.

CONCLUSIONS

Our results show that solubility is a decisive factor contributing to the sensitization capacity of allergens. The reduction in sensitization capacity of insoluble, particle-loaded antigens results from enhanced antigen uptake and presentation compared to soluble allergens.

Localization and antigenicity reduction of immunodominant conformational IgE epitopes on αs1-casein

αs1-Casein (αs1-CN) is the major allergen in cow milk; however, the understanding of its conformational epitopes remains limited due to the absence of a well-defined three-dimensional structure, which has impeded efforts to effectively reduce its antigenicity. This study employed molecular dynamics simulations (MD), ELISA, cell assays and peptidomes analysis to investigate the critical conformational epitopes of αs1-Casein. MD and immunological analyses identified a dominant conformational epitope encompassing the regions S55-E75 & Y154-T174 & F179-W199, which exhibited strong binding affinity to IgE and triggered the releasing of β-hexosaminidase, histamine and IL-6 in KU812 cells, thereby inducing allergic responses. Notably, the segments Y154-T174 and F179-W199 were particularly impactful. Furthermore, the presence of helical structures within the epitopes enhanced their binding to IgE to a certain extent. Peptidomes analysis further revealed that papain efficiently disrupted the key epitope (Y154-T174) by selectively cleaving the hotspot amino acid residues (Y154 and Y165), thereby significantly reducing the antigenicity of αs1-CN, decreasing IgE and IgG binding to 7.28 % and 10.39 %, respectively. These findings enhance the understanding of αs1-CN's antigenic epitopes and provides a theoretical and technical foundation for the targeted reduction of its antigenicity.

On the role of antibody affinity and avidity in the IgE-mediated allergic response

Type I hypersensitivity, also known as classical allergy, is mediated via allergen-specific IgE antibodies bound to type I FcR (FcεRI) on the surface of mast cells and basophils upon cross-linking by allergens. This IgE-mediated cellular activation may be blocked by allergen-specific IgG through multiple mechanisms, including direct neutralization of the allergen or engagement of the inhibitory receptor FcγRIIb which blocks IgE signal transduction. In addition, co-engagement of FcεRI and FcγRIIb by IgE-IgG-allergen immune complexes causes down regulation of receptor-bound IgE, resulting in desensitization of the cells. Both, activation of FcεRI by allergen-specific IgE and engagement of FcγRIIb by allergen-specific IgG are driven by allergen-binding. Here we delineate the distinct roles of antibody affinity versus avidity in driving these processes and discuss the role of IgG subclasses in inhibiting basophil and mast cell activation.

Development of an Automated Capture-SELEX Device for Efficient Screening of β-Conglycinin Aptamer

β-Conglycinin is the main allergen present in soybeans, and it is causing wide concern due to its notable allergenicity, heat, and digestive enzyme resistance. Screening for aptamers that both recognize β-conglycinin and inhibit the allergic reactions that it triggers is necessary. Conventional aptamer screening is labor-intensive, requires skilled personnel, and has limited reproducibility. To address these limitations, an automated device was developed to enhance the efficiency of aptamer selection in Capture-SELEX. The device achieves highly integrated, reproducible, and accurate contamination control. Using this device, a high-affinity and specific aptamer, β-5, was selected with a Kd = 18.24 ± 2.42 nM for β-conglycinin, as confirmed by isothermal titration calorimetry and fluorescence polarization. Thermodynamic analysis revealed that enthalpy-driven binding and docking simulations clarified the recognition mechanism. Overall, this automated device enables high-efficiency aptamer generation for certain targets, with aptamer β-5 expected to play a vital role in the detection of β-conglycinin and the targeted inhibition of its allergic reaction.

Dietary fiber pectin alters the gut microbiota and diminishes the inflammatory immune responses in an experimental peach allergy mouse model

Since therapeutic options are limited the utilization of prebiotics is suggested to prevent food allergies (FAs). Using an experimental peach allergy model we explored the effect of dietary fiber pectin, a high-methoxyl heteropolysaccharide, on the manifestation of FA. CBA/J mice were sensitized, subsequently orally boosted and provoked with peach peel extract. For dietary intervention, mice were fed a pectin containing diet before (primary-preventive) or after (secondary-preventive) sensitization. Non-treated allergic and sham-treated mice were fed a diet containing 20% cellulose. Fecal microbiota, humoral and intestinal immune cell responses were analyzed. Pectin remarkably affected the gut microbiota composition and diversity, promoting mainly the growth of Bacteroides. The frequency of mast cells, macrophages, and CD3+T cells in the lamina propria of the small intestine was reduced, whereas the frequency of B cells and CD4+T cell subpopulation was enhanced. Pectin intervention in the primary-preventive stetting significantly triggered serum IgA levels, whereas production of IgE and mMCPT-1 was reduced. Remarkably, in both settings peach allergen-specific IgG1/IgG2a ratio and specific IgE were significantly reduced to baseline. The data suggest, that dietary supplementation of pectin in both intervention approaches can diminish inflammatory responses and signs of allergic immune responses, accompanied by alteration of the gut microbiota composition.

Fecal microbiota transplantation as a new way for OVA-induced atopic dermatitis of juvenile mice

Children all over the world suffer from atopic dermatitis (AD), a prevalent condition that impairs their health. Corticosteroids, which have long-term negative effects, are frequently used to treat AD. There has been a growing body of research on the gut microbiota's function in AD. Nevertheless, the function and underlying mechanisms of fecal microbiota transplantation (FMT) in AD children remain to be established. Therefore, in order to assess the preventive effects of FMT treatment on AD and investigate the mechanisms, we constructed an ovalbumin (OVA)-induced juvenile mouse AD model in this investigation. This study explored the role and mechanism of FMT treatment in AD through 16S RNA sequencing, pathological histological staining, molecular biology, and Flow cytometry. Results demonstrated that the FMT treatment improved the gut microbiota's diversity and composition, bringing it back to a level similar to that of a close donor. Following FMT treatment, OVA-specific antibodies were inhibited, immunoglobulin (Ig) E production was decreased, the quantity of mast cells and eosinophils was decreased, and specific inflammatory markers in the skin and serum were decreased. Further mechanistic studies revealed that FMT treatment induced CD103+ DCs and programmed cell death ligand 1 (PD-L1)/programmed cell death 1 (PD-1) expression in skin-draining lymph nodes and promoted Treg production to induce immune tolerance and suppress skin inflammation. Meanwhile, changes in the gut microbiota were substantially correlated with Th2 cytokines, OVA-specific antibodies, and PD-L1/PD-1. In conclusion, FMT regulates the Th1/Th2 immunological balance and the gut microbiota. It may also inhibit AD-induced allergy responses through the PD-L1/PD-1 pathway, and providing a unique idea and possibly a fresh approach to the treatment of AD.

Subcutaneous immunotherapy for bee venom allergy induces epitope spreading and immunophenotypic changes in allergen-specific memory B cells

BACKGROUND

Allergen immunotherapy (AIT) is the only disease-modifying treatment for allergic disorders. We have recently discovered that allergen-specific memory B cells (Bmem) are phenotypically altered after 4 months of sublingual AIT for ryegrass pollen allergy. Whether these effects are shared with subcutaneous allergen immunotherapy (SCIT) and affect the epitope specificity of Bmem remain unknown.

OBJECTIVE

The study aimed to evaluate the phenotype and antigen receptor sequences of Bmem specific to the major bee venom (BV) allergen Api m 1 before and after ultra-rush SCIT for BV allergy.

METHODS

Recombinant Api m 1 protein tetramers were generated to evaluate basophil activation in a cohort of individuals with BV allergy before and after BV SCIT. Comprehensive flow cytometry was performed to evaluate and purify Api m 1-specific Bmem. Immunoglobulin genes from single Api m 1-specific Bmem were sequenced and structurally modeled onto Api m 1.

RESULTS

SCIT promoted class switching of Api m 1-specific Bmem to IgG2 and IgG4 with increased expression of CD23 and CD29. Furthermore, modeling of Api m 1-specific immunoglobulin from Bmem identified a suite of possible new and diverse allergen epitopes on Api m 1 and highlighted epitopes that may preferentially be bound by immunoglobulin after SCIT.

CONCLUSIONS

AIT induces shifting of epitope specificity and phenotypic changes in allergen-specific Bmem.

Evaluating the Therapeutic Potential of Microneedle Patch Laser With Multiple Wavelengths in Allergic Rhinitis: Insights From an Allergic Rhinitis Mouse Model

OBJECTIVE

There is insufficient evidence to determine the effectiveness of treating allergic rhinitis with a patch laser affix to the skin as opposed to direct intranasal irradiation of the nasal mucosa. We aimed to evaluate the effect of the microneedle patch laser with multiple wavelengths in an allergic rhinitis (AR) mouse model and its underlying mechanism.

METHODS

The microneedle patch laser was attached to the skin above the mouse's nasal cavity, transmitting light to the nasal mucosa. For 10 days, the microneedle patch laser administered simultaneous exposure to wavelengths of 670, 780, 850, and 910 nm at either 10 or 20 min each day. Multiple allergic parameters were evaluated following the microneedle patch laser treatment.

RESULTS

Microneedle patch laser treatment decreased allergic symptoms and inhibited OVA-specific IgE levels. Additionally, it significantly reduced eosinophil infiltration, epithelial thickness of the nasal mucosa, and IL-4 cytokine levels.

CONCLUSION

The light emitted by the microneedle patch laser attached to the skin, penetrated effectively to the nasal mucosa within the nasal cavity, suggesting potential for treating allergic rhinitis in mice and could be extended in clinical applications.

Adjuvant Effect of Lactobacillus paracasei in Sublingual Immunotherapy of Asthmatic Mice

Background: Sublingual immunotherapy (SLIT) has shown promise in mitigating allergic asthma symptoms; nevertheless, its high dose and prolonged duration of treatment raise safety concerns. This study explored the potential of Lactobacillus paracasei (L. paracasei) to enhance the effectiveness of SLIT in a mouse model of allergic asthma. Methods: Allergic asthma was induced in Balb/c mice following sensitization and challenge with a house dust mite (HDM) allergen. Subsequently, the mice were subjected to SLIT (66 and 132 µg) either alone or in combination with L. paracasei supplementation. Asthma-associated parameters, including rubbing frequency, IgE level, cytokine profiles, and histological changes, were evaluated to assess treatment efficacy. Results: mice that received SLIT 132 µg combined with the probiotic (combined 132) demonstrated a significant reduction in allergic symptoms (rubbing). This treatment strategy led to a marked IgE and eosinophil level decrease in serum; an increase in anti-inflammatory cytokines like IFN-γ and IL-10; and a reduction in pro-inflammatory cytokines IL-17 and TNF-α. The combination therapy also mitigated lung inflammation and supported the restoration of the structural integrity of the colon, promoting the recovery of goblet cells and mucus secretion. Probiotic treatment alone also effectively reduced IgE levels, increased IFN-γ, and decreased levels of IL-17 and TNF-α. Conclusions: The adjuvant effect of L. paracasei in enhancing SLIT represents a promising approach for improving asthma treatment efficacy.

Immunoglobulin-coating patterns reveal altered humoral responses to gut bacteria in pediatric cow milk allergies

BACKGROUND

Pediatric cow milk allergies (CMA) can occur in immunoglobulin (Ig) E and non-IgE-mediated forms. Unlike IgE-mediated allergies, the mechanisms of disease pathogenesis in non-IgE-mediated food allergy and an association with microbiome has not been well established. Previous studies have identified the presence of altered humoral responses to gut bacteria in IgE mediated allergies. Here, we analyzed IgA, IgE and IgG responses to gut bacteria in subjects with either IgE or non-IgE mediated CMA to identify relative proportions of Ig-coated bacteria and characterize unique disease specific microbial signatures.

METHODS

Multi-parametric flow cytometry analysis was used to identify IgA, IgE and IgG responses to gut bacteria in CMA patients. Cell sorting of Ig coated gut bacteria was subsequently performed followed by high throughput 16S rRNA gene sequencing and specific patterns of humoral responses to gut bacteria assessed in each study group.

RESULTS

We identified significant alterations in IgA and IgG gut bacterial coating patterns in CMA subjects. Proportions of IgA-coated bacteria were decreased in IgE mediated CMA subjects without atopic dermatitis (ALL) and non-IgE mediated CMA subjects (ENP), compared to healthy controls (CON). In comparison, IgG-coated bacteria was significantly elevated in CMA subjects with atopic dermatitis (AD). Alpha and beta diversities displayed significant differences in IgA-, IgE-, and IgG-coated bacteria in AD and ENP groups. Significant differences in bacteria coated by IgA, IgE and IgG were detected at Phyla, Genus and Species levels and associated bacterial dysbiosis in IgE and non-IgE mediated allergies were identified. Linear discriminant analysis (LDA) effect size (LEFse) revealed unique disease associated bacterial signatures, including several pathogenic bacteria namely Bacteroides fragilis, Ruminococcus gnavus, Eubacterium dolichum, Fusobacterium, Clostridium neonatale and Robinsoniella peoriensis. Receiver operating characteristic curve analysis confirmed the efficiency of using the bacterial signatures identified as biomarkers for disease.

CONCLUSIONS

Altered IgA and IgG responses to gut bacteria were identified in CMA subjects. The disease-specific responses were associated with alterations in bacterial diversity and concomitant dysbiosis of Ig-coated bacteria in IgE-mediated and non-IgE-mediated CMA pediatric subjects. The identification of pathogenic bacteria uniquely associated with different classes of allergic disease indicates a role of these bacteria in driving disease-specific pathological phenotypes.

IgE versus IgG and IgA: Differential roles of allergen-specific antibodies in sensitization, tolerization, and treatment of allergies

The prevalence of asthma, rhinitis, and food allergies has increased dramatically over the last few decades. This increase originally started in western countries, but is now also evident in many other regions of the world. Given the fact that the increase is so quick, the noted increase cannot be linked to a genetic effect, and many environmental factors have been identified that are associated with increased or reduced prevalence of allergies, like changing dietary habits, increased urbanization, pollution, exposure to microorganisms and LPS, and the farming environment and raw milk consumption. Although the key role of allergen-specific IgE in allergies is well known, the role of allergen-specific IgG and IgA antibodies is less well defined. This review will provide an overview of the functions of allergen-specific IgE in allergy, the role of allergen-specific antibodies (IgG (4) and IgA) in allergen immunotherapy (AIT), the possibility to use allergen-specific antibodies for treatment of ongoing allergies, and the potential role of allergen-specific antibodies in tolerance induction to allergens in a preventive setting. In the last, more speculative, section we will present novel hypotheses on the potential role of allergen-specific non-IgE antibodies in allergies by directing antigen presentation, Th2 development, and innate immune training.

Antibodies in breast milk: Pro-bodies designed for healthy newborn development

This manuscript sheds light on the impact of maternal breast milk antibodies on infant health. Milk antibodies prepare and protect the newborn against environmental exposure, guide and regulate the offspring's immune system, and promote transgenerational adaptation of the immune system to its environment. While the transfer of IgG across the placenta ceases at birth, milk antibodies are continuously replenished by the maternal immune system. They reflect the mother's real-time adaptation to the environment to which the infant is exposed. They cover the infant's upper respiratory and digestive mucosa and are perfectly positioned to control responses to environmental antigens and might also reach their circulation. Maternal antibodies in breast milk play a key role in the immune defense of the developing child, with a major impact on infectious disease susceptibility in both HIC and LMIC. They also influence the development of another major health burden in children-allergies. Finally, emerging evidence shows that milk antibodies also actively shape immune development. Much of this is likely to be mediated by their effect on the seeding, composition and function of the microbiota, but not only. Further understanding of the bridge that maternal antibodies provide between the child and its environment should enable the best interventions to promote healthy development.

Depression of CaV1.2 activation and expression in mast cells ameliorates allergic inflammation diseases

Allergic inflammation is closely related to the activation of mast cells (MCs), which is regulated by its intracellular Ca2+ level, but the intake and effects of the intracellular Ca2+ remain unclear. The Ca2+ influx is controlled by members of Ca2+ channels, among which calcium voltage-gated channel subunit alpha1 C (CaV1.2) is the most robust. This study aimed to reveal the role and underlying mechanism of MC CaV1.2 in allergic inflammation. We found that CaV1.2 participated in MC activation and allergic inflammation. Nimodipine (Nim), as a strong CaV1.2-specific antagonist, ameliorated allergic inflammation in mice. Further, CaV1.2 activation in MC was triggered by phosphatizing at its Ser1928 through protein kinase C (PKC), which calcium/calmodulin-dependent protein kinase II (CaMKII) catalyzed. Overexpression or knockdown of MC CaV1.2 influenced MC activation. Importantly, CaV1.2 expression in MC had detrimental effects, while its deficiency ameliorated allergic pulmonary inflammation. Results provide novel insights into CaV1.2 function and a potential drug target for controlling allergic inflammation.