Activation of the aryl hydrocarbon receptor improves allergen-specific immunotherapy of murine allergic airway inflammation: a novel adjuvant option?

Background: Allergen-specific immunotherapy (AIT) is able to restore immune tolerance to allergens in allergic patients. However, some patients do not or only poorly respond to current treatment protocols. Therefore, there is a need for deeper mechanistic insights and further improvement of treatment strategies. The relevance of the aryl hydrocarbon receptor (AhR), a ligand-dependent transcription factor, has been investigated in several inflammatory diseases, including allergic asthma. However, its potential role in AIT still needs to be addressed. Methods: A murine model of AIT in ovalbumin-induced allergic airway inflammation was performed in AhR-deficient (AhR-/-) and wild-type mice. Furthermore, AIT was combined with the application of the high-affinity AhR agonist 10-chloro-7H-benzimidazo[2,1-a]benzo[de]iso-quinolin-7-one (10-Cl-BBQ) as an adjuvant to investigate the effects of AhR activation on therapeutic outcome. Results: Although AhR-/- mice suffer stronger allergic responses than wild-type mice, experimental AIT is comparably effective in both. Nevertheless, combining AIT with the administration of 10-Cl-BBQ improved therapeutic effects by an AhR-dependent mechanism, resulting in decreased cell counts in the bronchoalveolar fluid, decreased pulmonary Th2 and Th17 cell levels, and lower sIgE levels. Conclusion: This study demonstrates that the success of AIT is not dependent on the AhR. However, targeting the AhR during AIT can help to dampen inflammation and improve tolerogenic vaccination. Therefore, AhR ligands might represent promising candidates as immunomodulators to enhance the efficacy of AIT.

[Efficacy and safety of dust mite subcutaneous immunotherapy in children with allergic asthma： a prospective randomized controlled study]. / å°˜èž¨çš®ä¸‹å ç–«æ²»ç–—åº”ç”¨äºŽå„¿ç«¥è¿‡æ•æ€§å“®å–˜ç–—æ•ˆä¸Žå®‰å ¨æ€§çš„å‰çž»æ€§éšæœºå¯¹ç §ç ”ç©¶.

OBJECTIVES: To investigate the efficacy and safety of subcutaneous immunotherapy (SCIT) using dust mites in children with allergic asthma. METHODS: In a prospective randomized controlled study, 98 children with dust mite-induced allergic asthma were randomly divided into a control group (n=49) and an SCIT group (n=49). The control group received inhaled corticosteroid treatment, while the SCIT group additionally received a standardized three-year SCIT regimen. The two groups were compared based on peripheral blood eosinophil percentage, visual analogue score (VAS), total medication score, Asthma Control Test/Childhood Asthma Control Test scores, fractional exhaled nitric oxide (FeNO), and lung function before treatment, and at 6 months, 1 year, 2 years, and 3 years after treatment. Adverse reactions were recorded post-injection to evaluate the safety of SCIT. RESULTS: Compared with pre-treatment levels, the SCIT group showed a significant reduction in the percentage of peripheral blood eosinophils, VAS, total medication score, and FeNO, while lung function significantly improved, and asthma control levels were better 3 years after treatment (P<0.05). Compared with the control group, the SCIT group showed more significant improvement in all evaluated indicators 3 years after treatment (P<0.05). A total of 2 744 injections were administered, resulting in 157 cases (5.72%) of local adverse reactions and 4 cases (0.15%) of systemic adverse reactions, with no severe systemic adverse events. CONCLUSIONS: SCIT is an effective and safe treatment for allergic asthma in children.

Current Management of Allergic Rhinitis.

Allergic rhinitis (AR) is the most common allergic disease worldwide and one of the most common chronic diseases in general. Allergic rhinitis is caused by inhalant allergens from outdoor and indoor environments with varying significance of different allergens in global regions. We provide options for the current management for AR including pharmacological treatments and nonpharmacological options and allergen immunotherapy (AIT). A literature review has been conducted in Medline, Pubmed, as well as the national and international study (ClinicalTrials.gov) and guideline registers and the Cochrane Library. Human studies published on the topic in the period up to and including November 2023 were taken into account. Allergen avoidance measures, pharmacotherapy, and AIT are the cornerstones of AR treatment. Nonpharmacological measures and behavioral recommendations should be adequately added. Tools of precision medicine are already playing a significant role and will be part of the diagnostic and therapeutic standard in the future. Patients benefit most in a network of different pharmacological and nonpharmacological treatment measures including AIT. Application of precision medicine tools for diagnosis and treatment will improve standards of care.

Increased inhibitory surface marker PD-1 expression in CD4+T cells and Th2+T cells in allergen-specific immunotherapy.

Recent evidence has shown that T cell exhaustion is implicated in Allergen-specific Immunotherapy (AIT). However, how T cell exhaustion plays a role in AIT is far from clear. Our study aimed to investigate T cell exhaustion associated with allergen exposure during AIT in mice. Ovalbumin (OVA) - sensitized C57BL/6J asthma mouse and AIT mouse models were constructed. Quantitative real-time PCR (qRTPCR) and flow cytometry were used to monitor the occurrence of local and systemic CD4+ T cells and Th2+T cells exhaustion in OVA-sensitized mice. The inhibitory surface marker programmed cell death protein 1 (PD-1) on CD4+ T cells and Th2+T cells was significantly upregulated in AIT mice compared with asthmatic and control mice. The level of PD-1 on the surface of CD4+T cells of asthma mice was significantly higher than that of control mice. The inhibitory surface marker cytotoxic T lymphocyte-associated protein 4 (CTLA-4) on CD4+ T cells and Th2+T cells showed no significant difference between the AIT, asthma and control mice. Collectively, our study indicated that the expression of PD-1 on CD4+ T cells and Th2+T cells was increased in AIT. Allergen exposure promotes the expression of PD-1 on the surface of CD4+ T cells. T cell exhaustion plays an important role in AIT.

Soluble antigen arrays provide increased efficacy and safety over free peptides for tolerogenic immunotherapy.

Autoantigen-specific immunotherapy using peptides offers a more targeted approach to treat autoimmune diseases, but clinical implementation has been challenging. We previously showed that multivalent delivery of peptides as soluble antigen arrays (SAgAs) efficiently protects against spontaneous autoimmune diabetes in the non-obese diabetic (NOD) mouse model. Here, we compared the efficacy, safety, and mechanisms of action of SAgAs versus free peptides. SAgAs, but not their corresponding free peptides at equivalent doses, efficiently prevented the development of diabetes. SAgAs increased the frequency of regulatory T cells among peptide-specific T cells or induce their anergy/exhaustion or deletion, depending on the type of SAgA used (hydrolysable (hSAgA) and non-hydrolysable 'click' SAgA (cSAgA)) and duration of treatment, whereas their corresponding free peptides induced a more effector phenotype following delayed clonal expansion. Over time, the peptides induced an IgE-independent anaphylactic reaction, the incidence of which was significantly delayed when peptides were in SAgA form rather than in free form. Moreover, the N-terminal modification of peptides with aminooxy or alkyne linkers, which was needed for grafting onto hyaluronic acid to make hSAgA or cSAgA variants, respectively, influenced their stimulatory potency and safety, with alkyne-functionalized peptides being more potent and less anaphylactogenic than aminooxy-functionalized peptides. Immunologic anaphylaxis occurred in NOD mice in a dose-dependent manner but not in C57BL/6 or BALB/c mice; however, its incidence did not correlate with the level of anti-peptide antibodies. We provide evidence that SAgAs significantly improve the efficacy of peptides to induce tolerance and prevent autoimmune diabetes while at the same time reducing their anaphylactogenic potential.

Fluctuation of Disease Severity and Quality of Life Applying Intralymphatic Immunotherapy for Patients with Seasonal Allergic Rhinitis.

Allergen-specific immunotherapy is the only disease-modifying treatment for IgE-mediated allergic disorders. Intra lymphatic immunotherapy (ILIT) is an efficacious and time-saving alternative to subcutaneous immunotherapy (SCIT). This study aimed to evaluate the effects and safety of ILIT in patients with moderate to severe allergic rhinitis.  In this clinical trial, patients between 18 and 65 years old with moderate to severe allergic rhinitis were enrolled. They received monthly intra-lymphatic inguinal injections of an active allergen (1000 SQ-U Salsola kali pollen). Their clinical symptoms were assessed before and four weeks after treatments. The clinical signs were also evaluated during two consecutive pollination seasons and the following non-pollination season in April. No moderate or severe reactions were recorded following ILIT treatment. Lymph node enlargement, angioedema/urticaria, and local itching were seen instantly after injection. Patients who received ILIT experienced a significant clinical improvement in self-recorded seasonal allergic symptoms after the treatments, compared to themselves before ILIT. Furthermore, their quality of life significantly improved. This study suggests ILIT with Salsola-pollen extract may decrease symptoms of allergic rhinitis. It was safe and did not cause any crucial complications.

[Preventive effects of allergen immunotherapy to pneumallergens]. / Prévention des manifestations allergiques par une immunothérapie aux pneumallergènes.

Allergen immunotherapy is still the only curative treatment for respiratory allergies. It is based on repeated administration of allergenic extracts to sensitized patients. It can be administered either by subcutaneous or by sublingual route. The purpose of the treatment is to modulate the immune response to a specific allergen and to alter the course of the disease over a long-term period. Numerous studies and meta-analyses have demonstrated its efficacy in terms of symptoms and quality of life improvement as well as reduction of the allergic march. Indication of allergen immunotherapy includes moderate to severe allergic rhinitis and mild to moderate allergic asthma from GINA step 3. Early intervention in sensitized patients is nowadays promoted.

L'immunothérapie allergénique représente, encore aujourd'hui, le seul traitement curatif des allergies respiratoires. Elle consiste en l'administration répétée d'extraits allergéniques auxquels le patient est allergique. Elle peut se faire par voie sous-cutanée ou sublinguale. L'objectif est de moduler la réponse immunitaire afin de réduire les symptômes de l'allergie et de modifier le cours de la maladie allergique avec des effets perdurant sur le long terme. De nombreuses études et méta-analyses ont prouvé son efficacité en termes d'amélioration symptomatique, d'amélioration de la qualité de vie mais également de la réduction de l'évolution de la marche allergique. L'immunothérapie allergénique est indiquée dans le traitement de la rhinite allergique modérée à sévère et de l'asthme allergique dès le palier 3 du GINA («Global Initiative for Asthma¼). Une utilisation plus précoce est de plus en plus mise en avant pour bénéficier des effets préventifs de la modulation immunitaire.

Development of a low allergenic product for patients with milk allergy and assessment of its specific IgE reactivity.

BACKGROUND: Milk oral immunotherapy is the riskiest and most unpredictable form of oral immunotherapy. We aimed to produce a low allergenic product than conventional once baked-cake/muffin, to develop indirect in-house ELISA to check the tolerance status with milk products and evaluate IgE reactivity of patients' sera via western blotting (WB) and indirect in-house ELISA. METHOD: A low allergenic product named biscotti-twice baked-cake was developed, and the total protein concentration was determined. The protein content was studied by SDS-PAGE and proteomics. Milk-specific IgE (sIgE) binding assays were performed by WB and indirect in-house ELISA by using patients' sera. RESULTS: Casein band intensity was observed to be lower in the biscotti-twice baked-cake than in the once baked-cake (p = .014). Proteomics analysis and αS1-casein measurement showed that the lowest intensity of casein was found in biscotti. The low binding capacity of milk sIgE to biscotti compared with once baked-cake was shown by WB (p = .0012) and by indirect in-house ELISA (p = .0001). In the ROC analysis, the area under the curve (AUC) of the in-house ELISA IgE was comparable with Uni-CAP milk and casein sIgE. The AUC of the in-house ELISA IgE for cake (0.96) and biscotti (1) was slightly better than Uni-CAP milk sIgE (0.94; 0.97) and casein sIgE (0.96; 0.97), respectively. CONCLUSION: The low allergenicity of the newly developed low allergenic product "biscotti-twice baked-cake" has been demonstrated by in vitro experiments. Biscotti could be a safe treatment option than once baked-cake/muffin in patients who are reactive to once baked-milk products.

[Chronic rhinosinusitis with nasal polyposis : A retrospective analysis of therapeutic approaches in 463 patients]. / Chronische Rhinosinusitis mit Polyposis nasi : Retrospektive Analyse des therapeutischen Vorgehens bei 463 Patienten.

BACKGROUND: Chronic rhinosinusitis with nasal polyps (CRSwNP) is a multifactorial inflammatory disease, the treatment of which has undergone significant changes in recent years. In addition to surgical approaches, topical and systemic steroids, and adaptive acetylsalicylic acid (ASA) desensitization, three specific antibodies have complemented the therapeutic portfolio since 2019. METHODS: A retrospective evaluation of all patients who presented as outpatients for the first time due to CRSwNP in 2007 and 2008 (collective A) and 2017 and 2018 (collective B) was performed, up to and including June 2023. RESULTS: The clinical courses of 463 patients (mean age 49.1 years, range 5-82 years; 65.9% male) were included in the analysis. Conservative treatment with nasal corticosteroids started before initial presentation was more frequent in collective B (collective A 43.9% vs. collective B 72.2%). In 278 of the 463 patients (60%; A: 62%, B: 58%), at least one operation on the nasal sinuses had been performed after initial presentation; in 101 of these patients (36.3%) recurrent polyposis (within mean follow-up of 2.4 years) required further treatment. The indication for ASA provocation/desensitization was applied less frequently in collective B, also due to a high discontinuation rate (at least 38%) of the maintenance therapy. Of the total cohort, 16 patients (3.5%; A: n = 8, B: n = 8) were meanwhile switched to antibody therapy at recurrence. CONCLUSION: A step-by-step guideline-orientated approach is recommended in the treatment of CRSwNP. Systemic antibodies as an add-on to nasal corticosteroids are a relatively new therapeutic option for treatment-refractory CRSwNP, which reduces the indication for ASA desensitization, which is associated with a relatively high incidence of side effects and poor compliance.

Food Allergy.

Food allergy is a growing health problem affecting both pediatric and adult patients. Food allergies are often immunoglobulin E (IgE) mediated but other food-induced non-IgE-mediated diseases exist. Diagnosis of food allergy relies on the combination of clinical and reaction history, skin and IgE testing as well as oral food challenges. Although oral immunotherapy has been able to achieve sustained unresponsiveness in some patients, no cure for food allergies has been found to date. Avoidance of the inciting food as well as availability of epinephrine autoinjectors remains the mainstay of treatment.

Oral Immunotherapy: An Overview.

Oral immunotherapy (OIT) is an alternative treatment of IgE-mediated food allergy that has been shown to increase tolerance threshold to many of the top food allergens, although this effect may be dependent on age, dose, frequency, and duration. OIT has been shown to be effective and safe in infants, and early initiation can improve rates of desensitization even for those foods whose natural history favors loss of allergy. Studies looking at protocol modification to improve OIT success are ongoing as is the evaluation of clinical tools to help monitor OIT effects.

Venom Hypersensitivity.

Stinging insects are a frequent cause of local and systemic hypersensitivity reactions, including anaphylaxis. For those with a history of life-threatening anaphylaxis, venom immunotherapy is effective, safe, and can be life-saving. Arachnids are a much less common source of envenomation through bites or stings and are less likely to cause a hypersensitivity reaction. However, recognizing the clinical manifestations when they do present is important for accurate diagnosis and treatment, and, when indicated, consideration of other diagnoses.

Successful rapid liposomal amphotericin B desensitization in pediatric case series.

Background: Liposomal amphotericin B (LAMB) is a crucial agent in the treatment of invasive fungal diseases caused by a wide variety of yeasts and molds. In the presence of an infection caused by a fungal agent resistant to alternative antifungal drugs, desensitization may be the only option to continue treatment. However, there is insufficient information and consensus with regard to amphotericin B desensitization protocols in the pediatric age group. Objective: We present our experience with five cases of patients in whom successful desensitization protocols were applied with LAMB, along with a review of the literature on pediatric cases. We also provide a sample desensitization protocol that we successfully applied. Methods: Pediatric patients who continued their treatment with the successful rapid desensitization protocol conducted at the Paediatric Allergy and Immunology Clinic of the Ministry of Health Ankara City Hospital between September 2019 and September 2023 were examined. Desensitization protocols were applied based on Castells' desensitization protocol. Results: Five patients ages between 5 and 12 years were referred to us due to the development of anaphylaxis during their treatment with LAMB. Anaphylaxis is diagnosed clinically, according to the European Academy of Allergy and Clinical Immunology guidelines: anaphylaxis (2021 update). A 16-step desensitization protocol was prepared by using LAMB solutions at four different dilutions (0.001, 0.01, 0.1, and 1 mg/mL). Each solution consisted of four steps, with a 15-minute infusion for each step. The patients were premedicated with 1 mg/kg/dose methylprednisolone and an antihistamine. Conclusion: The data we present on the successful application of a sample protocol to five cases, particularly in a pediatric setting, are noteworthy valuable contributions to the field, which demonstrates the feasibility and success of rapid desensitization with LAMB in pediatric patients. This can provide important insights and potentially serve as a reference for medical professionals working with similar cases in the future.

New evidence in food allergies treatment.

PURPOSE OF REVIEW: To acknowledge, the newly available treatments for food allergy described in the latest scientific literature, such as oral immunotherapy (OIT), biologics and the combination of them in managing patients with IgE-mediated food allergies. RECENT FINDINGS: Recent studies suggest that OIT and biologics, alone or together, can have a role as disease-modifying treatments for food allergies. The FDA has recently approved omalizumab as a treatment for food allergy. Other biologics are currently under evaluation and further studies are needed to assess the efficacy and safety of these therapies. SUMMARY: The allergology scenario is rapidly evolving, the recent introduction and approval of new therapeutic strategies such as biotechnological drugs and allergen immunotherapy is changing the therapeutic paradigm: we are witnessing a shift from a strategy based on avoiding the trigger and reversing an allergic reaction already in progress, to one that aims to modify the natural history of the disease by acting on the immunological mechanisms that determine it. This approach is consistent with the modern perspective of a personalized patient-tailored medicine. In this opinion review, we will provide a brief analysis of current and future therapeutic options for IgE-mediated food allergy, focusing on OIT, biologics and their combination.

A modified schedule of multiple aeroallergen ultra-rush immunotherapy in perennial allergic rhinitis: safety, efficacy, and T lymphocyte cell population studies.

BACKGROUND: This study assessed whether a modified immunotherapy schedule for allergic rhinitis could be safe and efficient. Ultra-rush immunotherapy (URIT) rapidly desensitizes patients to aeroallergens. OBJECTIVE: We aimed to develop a modified URIT protocol in 3 days to achieve the target dose while observing whether it could improve this situation and decrease the time to achieve the maintenance dose. METHODS: The URIT was exercised in 21 patients with perennial allergic rhinitis. Premeditations were given to the patients 3 days prior to the immunotherapy and during the 3 days injections immunotherapy: pred nisolone, ranitidine, and Airokast/montelukast. Finally, the T cell population frequencies of patients prior to and after immunotherapy, including T helper 1, T helper 2, cytotoxic T lymphocytes, and regulatory T cells, were studied using flow cytometry. During the URIT protocol, 21 patients received 291 injections. RESULT: Six patients (28.6%) showed systemic reactions in our study. All systemic reactions occurred on the third day by the 1:1 dilution of the maintenance dose. These systemic reactions occurred in three patients after 13 injections, and the three remaining patients showed systemic reactions following the last injection. No systemic reaction was observed on the first and second day of the therapy, and the risk of systemic reaction with every injection was about 2%. Among the T cell populations, CD3+ and CD8+ cells decreased significantly. CONCLUSION: The findings emphasized that URIT, alongside premedication with a high dose of antihistamine, helped to achieve the maintenance dose and control clinical manifestations.

Tablet allergen immunotherapy: the anaphylaxis issue.

For the first time 15 years ago, tablet allergen immunotherapy (T-AIT) formulations were approved by regulatory agencies for treating allergic rhinitis caused by grass pollen in adults and children aged >5 years. Extensive evidences existed about effectiveness and safety of AIT. However, the safety profile is particularly compelling in children. Generally, T-AIT causes local reactions, mostly in the oral cavity, that are usually mild-to-moderate and often self-resolving. However, systemic allergic reactions are also observed with T-AIT, anaphylaxis representing the most fearsome adverse event, considering that it occurs in subjects treated for allergic rhinitis. Therefore, we conducted a literature search of patients reporting anaphylaxis because of T-AIT. Nine cases of anaphylactic reactions were reported in literature. Notably, no death was reported using T-AIT. This outcome was very important as it underscored the substantial safety of T-AIT. However, T-AIT deserves careful attention, mainly in the pediatric population. In this regard, after the first report of anaphylactic reaction at the first administration of T-AIT, manufacturers recommended that the first dose should be administered in a medical facility in the presence of staff with experience in managing anaphylaxis and the patient should be observed for at least 30 min. Interestingly, reported anaphylactic reactions were due to grass pollen extracts, with no report concerning other allergen extracts. However, it is relevant to note that anaphylactic reactions because of T-AIT are not reported in recent years.