One hundred years of allergen immunotherapy: time to ring the changes

Effect of house dust mite sublingual immunotherapy in patients with adult atopic dermatitis with rhinitis

Aim: Whether house dust mite (HDM) sublingual immunotherapy (SLIT) is effective for the skin symptoms of adult atopic dermatitis (AD) is unclear.Methods: HDM SLIT was added to conventional AD treatment for 10 HDM-sensitized AD patients with rhinitis for 2 years.Results: Seven out of ten enrolled patients completed the study. Eczema Area and Severity Index score was significantly reduced when comparing before treatment and at 24 months follow-up. CD203c ratio in the basophil activation test using HDM extract, skin prick test with HDM extract and Dermatophagoides pteronyssinus/Dermatophagoides farinae specific-IgG4 tended to improve when comparing before treatment and after treatment.Conclusion: HDM SLIT might be a therapeutic option for AD patients with rhinitis who are sensitized to HDM.

Asthma and COPD: A Focus on β-Agonists - Past, Present and Future

Asthma has been recognised as a respiratory disorder for millennia and the focus of targeted drug development for the last 120 years. Asthma is one of the most common chronic non-communicable diseases worldwide. Chronic obstructive pulmonary disease (COPD), a leading cause of morbidity and mortality worldwide, is caused by exposure to tobacco smoke and other noxious particles and exerts a substantial economic and social burden. This chapter reviews the development of the treatments of asthma and COPD particularly focussing on the β-agonists, from the isolation of adrenaline, through the development of generations of short- and long-acting β-agonists. It reviews asthma death epidemics, considers the intrinsic efficacy of clinical compounds, and charts the improvement in selectivity and duration of action that has led to our current medications. Important β2-agonist compounds no longer used are considered, including some with additional properties, and how the different pharmacological properties of current β2-agonists underpin their different places in treatment guidelines. Finally, it concludes with a look forward to future developments that could improve the β-agonists still further, including extending their availability to areas of the world with less readily accessible healthcare.

Japanese Cedar Pollen Allergens in Japan

Pollen from members of the Cupressaceae tree family is one of the most important causes of allergic disease in the world. Cryptomeria japonica (Japanese cedar) and Chamaecyparis obtusa (Japanese cypress) are Japan's most common tree species. The pollen dispersal season is mainly from February to May. The major allergens of Japanese cedar and Japanese cypress exhibit high amino acid sequence similarity due to the phylogenetic relationship between the two species. An epidemiological study has shown that the prevalence of Japanese cedar pollinosis is approximately 40%. Younger children (5 to 9 years old) showed a high prevalence of Japanese cedar pollinosis as 30% in 2019, indicating that season pollinosis is getting worse. Pharmacotherapy is the most common treatment for pollinosis induced by Japanese cedar and Japanese cypress. Patients' satisfaction with pharmacotherapy is low due to insufficient experienced effect and daytime somnolence. Unlike pharmacotherapy, allergy immunotherapy (AIT) addresses the basic immunological mechanisms of allergic disease and activates protective allergen-reactive pathways of the immune system. AIT is now recognized as the only treatment option with the potential to provide long-term post-treatment benefits and alter the natural course of the allergic disease, including Japanese cedar pollinosis.

Allergen-specific immunotherapy induces monocyte-derived dendritic cells but attenuates their maturation and cytokine production in the lesional skin of an atopic dermatitis mouse model

Atopic dermatitis (AD) is a common inflammatory skin disease, but current treatments for AD are mostly limited to the alleviation of symptoms and inhibition of inflammation. Allergen-specific immunotherapy (ASIT) is the only curative approach for allergic diseases and could be a promising way to cure AD. Although ASIT has been gradually applied to patients with AD, there are still few studies on its efficacy evaluation and mechanisms. Based on our previous established AD mouse model by dinitrofluorobenzene and an extract of Dermatophagoides farina, we performed ASIT on this AD model through subcutaneous injection of Dermatophagoides farina extracts to evaluate the efficacy of ASIT and study its underlying mechanisms. Our results showed that ASIT could not only alleviate skin lesions and scratching behaviors of AD mice but also inhibit their Th2-type immune responses. Furthermore, ASIT could increase the infiltration of monocyte-derived dendritic cells in skin lesions but attenuated their maturation and production of interleukin 1α and interleukin 12/23 p40. As immature and semi-mature dendritic cells preferentially induce tolerance, accumulation but inhibition of maturation of monocyte-derived dendritic cells after ASIT may indicate a novel mechanism of ASIT and a potential therapeutic target for AD.

ICS/LABA Combined With Subcutaneous Immunotherapy Modulates the Th17/Treg Imbalance in Asthmatic Children

Rationale

The imbalance of T helper (Th17) cell and regulatory T (Treg) cell are involved in allergic asthma pathogenesis. We hypothesized that ICS/LABA could modulate the Th17/Treg imbalance and that subcutaneous immunotherapy (SCIT) could coordinate with ICS/LABA to rebalance the dysfunction of Th17/Treg.

Methods

Thirty house dust mites (HDM) allergic asthmatic children and fifteen healthy control subjects were enrolled in this study. Fifteen asthmatic children were treated by ICS/LABA powder inhalation, while the other fifteen asthmatic children were treated by ICS/LABA powder inhalation combined with HDM-SCIT. Asthmatic subjects were followed up for 6 months, but 2 asthmatics treated with ICS/LABA were lost to follow-up. Flow cytometry was used to determine the proportions of Th17 and Treg in CD4⁺ T cells from peripheral blood mononuclear cells (PBMCs). Serum levels of IL-17A and IL-10 were assessed by ELISA.

Result

ICS/LABA treatment significantly reduced the percentage of Th17 cells (1.252 ± 0.134% vs. 2.567 ± 0.386%), serum IL-17A (49.42 ± 2.643 pg/ml vs. 66.75 ± 3.442 pg/ml) and Th17/Treg ratio (0.194 ± 0.025 vs. 0.439 ± 0.072) compared to baseline (P<0.01). The ICS/LABA+HDM-SCIT treatment group showed similar reduction in the percentage of Th17 cells (1.11 ± 0.114% vs. 2.654 ± 0.276%), serum IL-17A (49.23 ± 2.131 pg/ml vs. 66.41 ± 2.616 pg/ml) and the Th17/Treg ratio (0.133 ± 0.015 vs. 0.4193 ± 0.050) (P<0.01). ICS/LABA+HDM-SCIT treatment group demonstrated elevated Treg percentages (8.483 ± 0.408% vs. 6.549 ± 0.299%) and serum IL-10 levels (127.4 ± 4.423 pg/ml vs. 93.15 ± 4.046 pg/ml), resulting in a lower Th17/Treg ratio than the ICS/LABA group.

Conclusion

ICS/LABA treatment regulates Th17/Treg imbalance mainly by mitigating Th17-induced inflammation in asthma patients. The addition of SCIT further enhanced such effect by upregulating Treg cells.

Adherence to subcutaneous immunotherapy with aeroallergens in real-life practice during the COVID-19 pandemic

Background

The success of subcutaneous immunotherapy (SCIT) mostly depends on regular injections. Our aim was to investigate adherence to SCIT with aeroallergens during the COVID‐19 pandemic and demonstrate clinical consequences of treatment disruptions in real life.

Methods

Visual analogue scale for quality of life (VAS‐QoL), VAS for symptom scores (VAS‐symptom), medication scores (MSs), and total symptom scores (TSS‐6) were recorded during the pandemic in 327 adult allergic rhinitis and/or asthmatic patients receiving maintenance SCIT, and these scores were compared with the pre‐pandemic data. Patients were grouped according to SCIT administration intervals; no delay (Group 1), <2 months (Group 2), and ≥2‐month intervals (Group 3).

Results

A total of 104 (31.8%) patients (Group 3) were considered as nonadherent which was mostly related to receiving SCIT with HDMs and using public transportation for reaching the hospital. Median MS, VAS‐symptom, and TSS‐6 scores of Group 3 patients during the pandemic were higher than the pre‐pandemic scores (p = 0.005, p < 0.001, p < 0.001, respectively), whereas median VAS‐QoL scores of Group 3 during the pandemic were lower than the pre‐pandemic scores (p < 0.001). Median TSS‐6 and VAS‐symptom scores were the highest in Group 3 compared with other groups (p < 0.001 for each comparison). Median VAS‐QoL scores were the lowest in Group 3 compared with Group 1 and Group 2 (p < 0.001, p = 0.043, respectively).

Conclusion

When precautions in allergy clinics are carefully applied, adherence to SCIT can be high during a pandemic. Patients must be encouraged to regularly adhere to SCIT injections since delays in SCIT administration can deteriorate clinical symptoms.

Absolute quantification of Bet v 1 in birch polymerized allergenic extracts via mass spectrometry-targeted analysis

BACKGROUND

Quantifying major allergens is essential for evaluating the quality and efficacy of allergenic extracts. They are usually measured in non-polymerized extracts using immunoassays. However, the direct measurement of allergens in allergoids is currently not supported. This study set out to develop a method for quantifying Bet v 1 in polymerized birch extracts using mass spectrometry-based targeted analysis.

METHODS

Three isotopically labelled peptide sequences of Bet v 1 were synthetized and used as internal standards for the development of a mass spectrometry-based targeted analysis. The calibration curves of the three peptides to assess the linearity and limit of detection, as well as reverse calibration curves with a constant amount of sample, were constructed. The Bet v 1 content was determined and measured in 18 batches of depigmented (native extracts purified by a mild acid treatment) and depigmented-polymerized extracts.

RESULTS

Bet v 1 isoforms were identified in both type of extracts by mass spectrometry. According to mass spectrometry-targeted analysis depigmented and depigmented-polymerized extracts exhibited mean values of 70.5 and 73.5 µg Bet v 1/mg of lyophilized extract, respectively. A statistically significant correlation between the allergen content of both extracts was identified. Statistically significant differences were observed when the Bet v 1 content in non-polymerized extracts was measured via mass spectrometry (70.5 ± 11.6 µg/mg) or immunoassay (83.7 ± 19.8 µg/mg).

CONCLUSIONS

These results represent the first direct quantification of Bet v 1 in allergoids using mass spectrometry-based targeted analysis. The proposed method demonstrates robustness and reliability and constitutes a promising alternative for detailed characterization of polymerized allergenic extracts.

COVID-19 vaccination and allergen immunotherapy (AIT) - A position paper of the German Society for Applied Allergology (AeDA) and the German Society for Allergology and Clinical Immunology (DGAKI)

Background: Vaccinations against severe acute respiratory syndrome coronavirus type 2 (SARS-CoV-2) are intended to induce an immune response to protect against infection/disease. Allergen immunotherapy (AIT) is thought to induce a (different) immune response, e.g., to induce tolerance to allergens. In this position paper we clarify how to use AIT in temporal relation to COVID-19 vaccination. Four SARS-CoV-2 vaccines are currently approved in the EU, and their possible immunological interactions with AIT are described together with practical recommendations for use. Materials and methods: Based on the internationally published literature, this position paper provides specific recommendations for the use of AIT in temporal relation to a SARS-CoV-2 vaccination. Results: AIT is used in 1) allergic rhinitis, 2) allergic bronchial asthma, 3) insect venom allergy, 4) food allergy (peanut). Conclusion: For the continuation of an ongoing AIT, we recommend an interval of 1 week before and after vaccination for subcutaneous immunotherapy (SCIT). For sublingual immunotherapy (SLIT) and oral immunotherapy (OIT), we recommend taking them up to the day before vaccination and a break of 2 – 7 days after vaccination. Initiation of a new SCIT, SLIT, or OIT should be delayed until 1 week after the day of the second vaccination. For SCIT, we generally recommend an interval of ~ 1 week to COVID-19 vaccination.

Real-life adherence to subcutaneous immunotherapy: What has changed in the era of the COVID-19 pandemic

BACKGROUND

Allergen immunotherapy (AIT) must be continued for 3 years, to achieve a long-term modifying effect. Adherence is a key to ensure effectiveness. The objective of this study was, first of all, to evaluate the adherence with subcutaneous immunotherapy (SCIT) and to identify the main causes of SCIT withdrawal in real-life practice in our clinic. Secondly, we also aimed to investigate to what extent the COVID-19 pandemic altered our SCIT receiving patients' treatment adherence behaviors and the factors that affected their decisions.

METHODS

Retrospective analysis of the medical records of patients ages ≥18 years, who had started SCIT in January 2014 or later until September 2020 in our department for the diagnosis of allergic rhinitis, allergic asthma or venom allergy, were included in the study. Adherence was determined as the accomplishment of 3 years of SCIT.

RESULTS

A total of 124 patients (72 female [58.1%]; median age, 35 [19-77] years) were included. The adherence rate to SCIT in our tertiary center's real-life setting was 56.25% with a follow-up duration of 3 years before COVID-19 pandemic. Dose modification, defined as reducing patient's planned SCIT dose due to a systemic allergic/large local reaction or missed injection, and its frequency, which is the number of dose adjustments done throughout the SCIT, was found to be the only factor related to nonadherence. But with the pandemic only in 6 months, among 63 patients receiving SCIT, 15 patients (23.81%) dropped out, and the most common reason was fear of being infected with COVID-19 virus during receiving SCIT in hospital (93.33%). The only independent predictor of drop-out during the COVID-19 pandemic was short duration of AIT (p = 0.012). When we compare the dropped-out cases before and after the start of pandemic, AIT duration was significantly shorter in pandemic period (p = 0.005).

CONCLUSION

Adherence rate to SCIT in our real-world setting study was 56.25% before the COVID-19 pandemic. Our results indicated that patients requiring dose modification were more prone to be non-adherent. Approximately one quarter of patients dropped-out with the start of pandemic, almost all due to fear of being infected during receiving SCIT in hospital. Since short SCIT follow-up time was found to be the only risk factor for drop-out during the COVID-19 pandemic, we believe that patients who are in the early phases of their treatment should be observed more closely and their concerns should be answered by their doctors.

One Hundred Ten Years of Allergen Immunotherapy: A Broad Look Into the Future

Allergen immunotherapy (AIT) is the only disease-modifying treatment option for patients with type 1-mediated allergic diseases such as allergic rhinitis/rhinoconjunctivitis with/without allergic asthma. Although many innovations have been developed since the first clinical report of Noon et al in 1911, the improvement of clinical efficacy and tolerability of this treatment is still an important unmet need. Hence, much progress has been made in the characterization of the cell types, cytokines, and intracellular signaling events involved in the development, maintenance, and regulation of allergic reactions, and also in the understanding of the mechanisms of tolerance induction in AIT. This comprehensive review aims to summarize the current innovative approaches in AIT, but also gives an outlook on promising candidates of the future. On the basis of an extensive literature review, integrating a clinical point of view, this article focuses on recent and future innovations regarding biologicals, allergen-derived peptides, recombinant allergens, "Toll"-like receptor agonists and other adjuvants, and novel application routes being developed for future AIT.

Specific Dermatophagoides farinae extract for canine immunotherapy

BACKGROUND

Canine atopic dermatitis (cAD) is a pruritic allergic skin disease most often caused by Dermatophagoides farinae. Differences in the sensitization profile to D. farinae have been reported between people and dogs. However, allergic dogs traditionally have been treated with extracts intended for human immunotherapy.

HYPOTHESIS/OBJECTIVES

To develop a specific allergen immunotherapy for veterinary practice enriched in canine major allergens and to demonstrate its in vitro efficacy.

ANIMALS

Twenty privately owned dogs, clinically diagnosed with cAD, and three healthy dogs.

METHODS AND MATERIALS

A veterinary D. farinae allergen extract was manufactured and characterized compared to D. farinae extract used for human immunotherapy. The protein profile was analysed by SDS-PAGE and size exclusion chromatography and Der f 15 and Der f 18 allergens quantified by mass spectrometry. The allergenic profile was studied by immunoblot and the biological potency by enzyme-linked immunosorbent assay-inhibition assays. The extract's capacity to induce cytokine production [interleukin (IL)-10, interferon (IFN)-Ɣ] by peripheral blood mononuclear cells also was evaluated.

RESULTS

The veterinary extract showed a higher content of high molecular weight proteins, preferentially recognized by atopic dog sera. The fold-increases in Der f 15 and Der f 18 with respect to the human extract were 2.07 ± 0.32 and 1.63 ± 0.15, respectively. The veterinary extract showed higher biological potency (0.062 versus 0.132 µg required for 50% inhibition of dogs sera) compared to the human extract and induced significantly higher levels of IL-10 (1,780 pg/mL) and IFN-Ɣ (50.4 pg/mL) with respect to the negative control.

CONCLUSIONS AND CLINICAL IMPORTANCE

A veterinary D. farinae extract with a higher content of dog major allergens was developed and in vitro efficacy demonstrated by immunological parameters.

Allergen immunotherapy in the current COVID-19 pandemic: A position paper of AeDA, ARIA, EAACI, DGAKI and GPA: Position paper of the German ARIA GroupA in cooperation with the Austrian ARIA GroupB, the Swiss ARIA GroupC, German Society for Applied Allergology (AEDA)D, German Society for Allergology and Clinical Immunology (DGAKI)E, Society for Pediatric Allergology (GPA)F in cooperation with AG Clinical Immunology, Allergology and Environmental Medicine of the DGHNO-KHCG and the European Academy of Allergy and Clinical Immunology (EAACI)H

No abstract available.

Mind the gaps: Clinical trial concepts to address unanswered questions in aeroallergen immunotherapy-An NIAID/AHRQ Workshop

The Agency for Healthcare Research and Quality and the National Institute of Allergy and Infectious Diseases organized a workshop to develop trial concepts that could improve the use and effectiveness of aeroallergen immunotherapy (AAIT). Expert groups were formed to accomplish the following tasks: (1) propose a study design to compare the effectiveness and safety of subcutaneous versus sublingual AAIT; (2) propose a study design to compare the effectiveness and safety of AAIT by using 1 or a few allergens versus all or most allergens to which a patient is sensitized; (3) propose a study design to determine whether AAIT can alter the progression of childhood allergic airways disease; and (4) propose a study design to determine the optimal dose and duration of AAIT to achieve maximal effectiveness with acceptable safety. Study designs were presented by the workgroups, extensively discussed at the workshop, and revised for this report. The proposed trials would be of long duration and require large highly characterized patient populations. Scientific caveats and feasibility matters are discussed. These concepts are intended to help the development of clinical trials that can address some of the major questions related to the practice of AAIT for the management and prevention of allergic airways disease.

Allergen-specific immunotherapy induces regulatory T cells in an atopic dermatitis mouse model

BACKGROUND

Several studies have demonstrated that allergen-specific immunotherapy (SIT) can be an effective treatment for atopic dermatitis (AD). However, there is no relevant mouse model to investigate the mechanism and validate the novel modality of SIT in AD.

METHODS

NC/Nga mice with induced AD-like skin lesions received a subcutaneous injection of SIT (an extract of the house dust mite Dermatophagoides farinae [DfE]) or placebo for 5 weeks). Clinical and histological improvements of AD-like skin lesions were examined. The responses of local and systemic regulatory T (Treg) cells, natural killer (NK) cells, B cells, serum immunoglobulin, and T-cell cytokine response to DfE were evaluated to determine the underlying mechanism of the observed results.

RESULTS

Specific immunotherapy significantly improved AD-like skin lesions. Histologically, SIT decreased epidermal thickness and reduced inflammatory cell infiltration, especially that of eosinophils. Concomitantly, SIT suppressed Th2 responses and induced local infiltration of Treg cells into the skin. Also, SIT induced the immunoglobulin G4 and attenuated allergen-specific immunoglobulin E. Furthermore, SIT induced local and systemic IL-10-producing Treg cells and regulatory NK cells.

CONCLUSION

We established a SIT model on AD mice and showed that our model correlates well with previous reports about SIT-treated patients. Also, we revealed NK cells as another possible resource of IL-10 in SIT. Based on our results, we suggest our SIT model as a useful tool to investigate mechanism of action of SIT and to validate the efficacy of new SIT modalities for the treatment of AD.

Ultra-short-course booster is effective in recurrent grass pollen-induced allergic rhinoconjunctivitis

BACKGROUND

A relevant proportion of allergic rhinoconjunctivitis (ARC) patients experience recurrent symptoms after successfully completing allergen immunotherapy (AIT). This prospective, controlled, noninterventional study used internationally standardized instruments to determine the clinical effects of a preseasonal, ultra-short-course booster AIT on clinical outcome parameters.

METHODS

This two-arm study included patients aged ≥12 years with recurrent grass pollen-induced seasonal AR who had completed a successful course of any grass pollen AIT at least 5 years before enrolment. Overall, 56 patients received one preseasonal short-course booster AIT using tyrosine-absorbed grass pollen allergoids containing the adjuvant monophosphoryl lipid A (MPL® ); 51 control patients received symptomatic medication. The combined symptom and medication score (CSMS) was recorded in the (peak) grass pollen season. Furthermore, concomitant (antiallergic) medication use, the patients' state of health, Mini Rhinoconjunctivitis Quality of Life Questionnaire (MiniRQLQ) results and safety/tolerability of the treatment were assessed.

RESULTS

The CSMS in the peak grass pollen season was significantly lower in the booster AIT group (Δ=38.4%, P<.01). Moreover, significantly more patients in this group used no concomitant antiallergic medication throughout the peak grass pollen season. Twice as many patients in the booster AIT group as in the control group reported having a better state of health than in the preceding season. MiniRQLQ results showed significant differences favouring the booster AIT. The booster AIT was generally well tolerated, with only two patients reporting mild, grade 1 systemic adverse events.

CONCLUSION

Booster AIT using tyrosine-absorbed allergoids containing the adjuvant MPL® effectively prevents re-occurrence of symptoms in patients with grass pollen-induced ARC.

Effect of Japanese cedar-specific sublingual immunotherapy on allergen-specific TH2 cell counts in blood

BACKGROUND

The contribution of antigen-specific TH cells in peripheral blood to immunologic mechanisms underlying sublingual immunotherapy (SLIT) remains unclear, partly because of the lack of a standardized method for the analysis of this rare lymphocyte subset.

OBJECTIVE

To clarify the role of antigen-specific TH cells during SLIT using a sensitive method analyzing activation marker CD154-positive TH cells with multicolor flow cytometry.

METHODS

We assessed antigen-specific TH cells using multicolor flow cytometry based on the expression of the activation marker CD154 and intracellular cytokines in patients with Japanese cedar pollinosis receiving SLIT at baseline and during the first pollen season after the initiation of SLIT.

RESULTS

A total of 18 patients between 12 and 44 years of age were enrolled in the present study. Of these, 8 patients received SLIT (SLIT group) and 10 patients received symptomatic treatment only (control group). Although seasonal pollen exposure significantly increased the number of Japanese cedar-specific interleukin 5- and interleukin 4-producing TH cells in the control group (P < .01 for both), SLIT ameliorated this increase in the SLIT group (P = .64 and P = .84, respectively).

CONCLUSION

The present study indicates that allergen-specific TH2 cells in peripheral blood are involved in mechanisms underlying SLIT. The analysis of antigen-specific TH cells using multicolor flow cytometry based on the expression of the activation marker CD154 represents a sensitive and relatively simple, standardized method for monitoring peripheral antigen-specific TH cells during allergen-specific immunotherapy.

Oral immunotherapy for food allergy: clinical and preclinical studies

Food allergies affect approximately 5% of the U.S. population and have increased in the last decade. In recent years, oral immunotherapy (OIT) has been tested in clinical trials for peanut, milk, and egg allergies in young children. OIT appears to be fairly well tolerated by most subjects and leads to desensitization with a greatly increased threshold of allergen required to induce reactions. Further approaches being investigated in preclinical studies in mouse models indicate the potential for using adjuvants, such as TLR9 agonists in combination with OIT; peptide OIT; and non-allergen specific applications such as herbal formulations. Further questions about OIT remain, including the optimal dosing and length of treatment; whether tolerance can be developed; and the exact cellular mechanisms resulting in protection following OIT. With many clinical trials underway across the United States and other countries, and a growing pipeline of preclinical research with translational potential, there is great hope for a widely applicable food allergy treatment.

The rate of epinephrine administration associated with allergy skin testing in a suburban allergy practice from 1997 to 2010

Allergy skin testing is considered a safe method for testing for IgE-mediated allergic responses although anaphylactic events can occur. Reported rates of anaphylaxis per patient are not consistent and range from 0.008 to 4%. The aim of this study was to determine the rate of epinephrine use associated with allergy skin-prick testing (SPT) and intradermal testing (IDT) in a suburban practice over 13 years. This retrospective chart review used billing and procedure coding records during the time period from January 1997 to June 2010 to identify encounters where epinephrine was administered after SPT or IDT. Patient encounters with procedure codes for skin testing plus either parenteral epinephrine, corticosteroid, antihistamine, or i.v. fluid administration were identified. These patient charts were reviewed to determine if epinephrine was administered, whether systemic reactions developed, and rates of epinephrine administration were calculated. There were 28,907 patient encounters for SPT and 18,212 for IDT. Epinephrine was administered in six patient encounters (0.02%) where SPT was performed; no IDT encounters led to epinephrine administration. There were no fatalities. Allergy skin testing to a variety of allergens, when administered by well-trained personnel, is a safe procedure. This study, involving the largest population to date, showed a rate of systemic reactions requiring epinephrine of 20 per 100,000 SPT visits. No epinephrine was given after IDT.

[Role of allergen-specific immunotherapy (desensitization) for the treatment of allergies in Germany. Current situation]

Allergen-specific immunotherapy (SIT, desensitization) is applied monthly with subcutaneous injections (SCIT) or sublingually (SLIT) with droplets or tablets on a daily basis. Numerous immunological changes during SIT induce long-lasting tolerance. Efficacy has been demonstrated by a number of controlled studies for insect venom hypersensitivity (SCIT), allergic rhinoconjunctivitis (SCIT, SLIT particularly in grass pollen allergy), and allergic asthma (SCIT > SLIT). SIT is indicated in children and adults with severe allergic reactions from insect venoms (e.g., bee, wasp) or cumbersome symptoms from pollen, house dust mites or mold allergens and proven immediated-type allergy. Contraindications must be considered individually. SIT is performed for 3 years, in case of venom allergy 3-5 years. Severe systemic reactions are rare after SCIT. After SLIT rather local allergic symptoms of short duration occur in the mouth and throat. At present, the number prescriptions for SIT has decreased due to inadequate reimbursement of allergy-related services (diagnostics, therapies, monitoring). In the future, inferior medical care of allergic patients in Germany is expected, who until now have benefited from the preventive effects of SIT (reduced risk of developing asthma and new allergic sensitizations).

Epigenetic modifications and improved regulatory T-cell function in subjects undergoing dual sublingual immunotherapy

BACKGROUND

Allergen-specific immunotherapy is the only mode of therapy that has been demonstrated to offer a cure in patients with IgE-mediated respiratory allergies.

OBJECTIVE

We sought to demonstrate the safety and efficacy of timothy grass (TG) and dust mite (DM) dual sublingual immunotherapy (SLIT) and to begin to investigate the immune mechanisms involved in successful immunotherapy with multiple allergens.

METHODS

The safety and efficacy of dual SLIT with TG and DM in children and adults with demonstrated allergies to TG and DM were investigated in a single-center, randomized, double-blind, controlled phase I study. Thirty subjects received either TG and DM dual SLIT (n= 20) or placebo (n = 10). Immune parameters were evaluated for differentiation of desensitized subjects from control subjects.

RESULTS

Subjects treated with dual SLIT had decreased rhinoconjunctivitis scores (P < .001) and medication use scores (P < .001) and reduced responses to TG and DM allergen based on results of skin prick tests or nasal disk challenges (P < .01 and P < .001, respectively) compared with placebo-treated control subjects. An increase in TG- and DM-specific IgG(4) levels, reduced allergen-specific IgE levels, and subsequent basophil activation were observed in the active treatment group. Dual SLIT promoted allergen-specific suppressive CD4(+)CD25(high)CD127(low)CD45RO(+) forkhead box protein 3 (Foxp3)(+) memory regulatory T cells with reduced DNA methylation of CpG sites within the Foxp3 locus.

CONCLUSION

The results of this pilot study suggest that dual SLIT could be an effective means to treat subjects with sensitivities to a variety of allergens and that long-term tolerance might be induced by epigenetic modifications of Foxp3 in memory regulatory T cells.

Allergen immunotherapy practice patterns: a worldwide survey

BACKGROUND

Allergists around the world have different practice styles when administering subcutaneous aeroallergen immunotherapy (IT) in peak pollen seasons, especially when changing doses or frequency of IT. The Immunotherapy practice parameters do not specifically address this issue.

OBJECTIVE

Given the paucity of good data about adjustment of allergen immunotherapy during the pollen seasons, we examined whether a significant difference is present in the way allergists administer immunotherapy during allergy seasons.

METHODS

To quantify the practice styles of allergists who are members of the American Academy of Allergy, Asthma and Immunology (AAAAI), a self-reported electronic survey was disseminated in September 2010 with the help of the AAAAI Needs Assessment Committee. The responses were tallied and analyzed according to demographic information.

RESULTS

A total of 1,201 allergists in the AAAAI responded to the survey. Most responders practice in an urban or suburban nonacademic practice in the United States and have been in practice for more than 10 years. The size of their practice was variable. Those in practice for more than 10 years were more likely to adjust the dose and frequency of immunotherapy in pollen seasons.

CONCLUSION

This survey highlights the differences in the practice styles of AAAAI member allergists, and these differences may be associated with their demographic characteristics. Given the wide variability in how allergists adjust dose and frequency of immunotherapy during pollen seasons, establishing guidelines regarding this routine dilemma might help standardize the delivery of treatment to patients.

Long-term clinical and immunological effects of allergen immunotherapy

PURPOSE OF REVIEW

The present review updates current findings on long-term clinical and immunological outcomes after cessation of allergen immunotherapy for allergic respiratory disease.

RECENT FINDINGS

Recent studies have shown that allergen immunotherapy has sustained disease-modifying effects that persist for years after discontinuation. This is in contrast to the effects of antiallergic drugs that do not induce tolerance to offending allergens. Long-term effects of immunotherapy include a reduction in nasal symptoms, a decrease in the use of rescue medication and improvement in quality of life. These benefits are accompanied by immunological changes such as the induction of allergen-specific IgG antibodies with inhibitory activity for IgE-facilitated binding of allergen-IgE complexes to B cells. One study reported a reduction in the development of asthma in children with seasonal pollen-induced rhinitis.

SUMMARY

Allergen immunotherapy induces clinical and immunological tolerance as defined by persistence of clinical benefit and associated long-term immunological parameters after discontinuation of treatment. These findings are largely confined to studies of subcutaneous and sublingual immunotherapy for seasonal pollinosis. Further studies are needed to address potential long-term clinical effects for other seasonal and perennial inhaled allergens in both children and adults, and to identify potential biomarkers of tolerance.

Advances in upper airway diseases and allergen immunotherapy in 2011

The purpose of this review is to highlight recently published important articles on upper airway diseases and allergen immunotherapy. We review articles on rhinitis, sinusitis, conjunctivitis, and immunotherapy. New insights into epidemiology, pathophysiology, diagnosis, and therapy are described for each of the above diseases.

Association of subcutaneous allergen-specific immunotherapy with incidence of autoimmune disease, ischemic heart disease, and mortality

BACKGROUND

Subcutaneous allergen-specific immunotherapy (SCIT) is a well-documented treatment of IgE-mediated allergic disease. Little is known about potential effects of SCIT on the risk of other chronic immune-related diseases. Over the years, a few casuistic reports have caused concern that SCIT might act as a trigger of autoimmune disease.

OBJECTIVE

We aimed to investigate the association of SCIT with the incidence of autoimmune disease and ischemic heart disease (IHD), as well as all-cause mortality.

METHODS

All Danish citizens without other known diseases were linked and followed through central registries on medications and hospital admissions. Persons receiving SCIT and persons receiving conventional allergy treatment (CAT; nasal steroids or oral antihistamines) were compared with regard to mortality and development of autoimmune diseases, acute myocardial infarction (AMI), and IHD. Cox regression (survival analysis) with age as the underlying time scale was used to estimate relative risks (hazard ratios [HRs] with 95% CIs) associated with SCIT compared with CAT adjusted for age, sex, vocational status, and income.

RESULTS

During the 10-year study period (1997-2006), a total of 18,841 and 428,484 persons were followed in the SCIT and CAT groups, respectively. Receiving SCIT was associated with lower mortality (HR, 0.71; 95% CI, 0.62-0.81) and lower incidence of AMI (HR, 0.70; 95% CI, 0.52-0.93), IHD (HR, 0.88; 95% CI, 0.73-1.05), and autoimmune disease (HR, 0.86; 95% CI, 0.74-0.99).

CONCLUSION

In this registry-based observational study, receiving SCIT compared with CAT was associated with lower risk of autoimmune disease and AMI, as well as decreased all-cause mortality.

Systemic reactions to subcutaneous allergen immunotherapy

Subcutaneous allergen immunotherapy (SCIT) has been practiced for 100 years. Many trials have established the efficacy of SCIT in reducing symptoms of both seasonal allergic rhinitis and asthma due to aeroallergens. However, clinical benefits of SCIT are tempered by risks of injection-related systemic reactions and life-threatening anaphylaxis. This article reviews data derived from retrospective surveys conducted to define the incidence, prevalence, and factors contributing to injection-related fatal anaphylactic and near-fatal systemic reactions, as well as recently initiated longitudinal surveillance studies of SCIT reactions.

Close collaboration between academia, industry and drug regulators is required in the development of allergen products for specific immunotherapy in children

Modification of the response to allergens at an early stage and thereby of the natural history of a respiratory allergic disease by preventing disease progression would constitute the key benefit of specific immunotherapy (SIT) in children. However, although allergen products for SIT have been on the market on a named-patient basis for many years, long-term efficacy, the optimal duration of the treatment and the optimal dosage have not been sufficiently elaborated until now. The enactment of the Therapy Allergen Ordinance in Germany mandates that allergen products for SIT of the most prevalent allergies must submit an application for marketing authorization to the German authorities. In line with the European Paediatric Regulation, decisions by the European Medicines Agency on agreed paediatric investigation plans must be included in these applications. These regulatory requirements provide a unique opportunity to fill the gap in knowledge concerning the benefits of SIT for children and to obtain the data needed to support evidence-based authorization of allergen products for immunotherapy. This goal can only be achieved through close cooperation between academia, drug regulators and industry as well as parent/patient organizations.