Different Development Forms of Local Allergic Rhinitis towards Birch

Local Allergic Rhinitis

Local allergic rhinitis (LAR) is defined by a clinical history suggestive of allergic rhinitis (AR), negativity of systemic IgE measurement and positive response to nasal allergen challenge (NAC). The term local respiratory allergy includes LAR, local allergic asthma (positive response in bronchial allergen challenge) and dual allergic rhinitis defined by the coexistence of AR and LAR. LAR worsens in severity and presence of comorbidities over time, and it is an independent entity from AR. Prevalence is higher in Mediterranean countries. LAR onset occurs during childhood in 36% of cases. Physiopathological features of LAR are: increased nasal eosinophilic inflammation, tryptase and eosinophil cationic protein, and presence of nasal specific IgE in secretions of 20-40% of subjects. A recent study demonstrated increase in sequential class switch recombination to IgE markers in mucosa of LAR with accumulation of IgE+ CD38+ plasmablasts. Moreover, there is increased expression in B cells of mucosal homing receptors CXCR3+ and CXCR4 in peripheral blood, with accumulation of Th9 and Th2 cells. NAC is the gold standard in the diagnosis of LAR. The measurement of specific IgE in nasal secretions basophil activation test or are still not suitable for diagnosis. There is ample evidence of the usefulness of allergen immunotherapy in the treatment in LAR after 4 DBPCRT in 152 patients. In conclusion, knowledge about LAR is continuously increasing, with detailed definition of physiopathological mechanisms and new phenotypes. More awareness of the disease should be promoted among different specialists, and NAC must be considered an essential diagnostic tool in any age group, including children.

[Research progress and clinical application of allergen nasal provocation test]

The allergen nasal provocation testing（NPT）, in which allergens are applied directly to the nasal mucosa under standard and controlled conditions to provoke the main symptoms of allergic rhinitis（AR）, reproduces the response of the upper respiratory tract to natural exposure to allergens under controlled conditions and is the only test currently available to confirm nasal reactivity to allergens. It is invaluable in studying the mechanisms of AR and in assessing the response to novel anti-allergic treatments. The test may play an increasingly important role in clinical practice, especially in the identification of local AR, the diagnosis of occupational AR, the clarification of the composition of allergens, the assessment of the efficacy of AR treatment and the selection of candidates undergoing allergen immunotherapy. This article reviewed the application of NPT in the diagnosis of allergic and non-allergic rhinitis, and also introduces the indications, contraindications, advantages and limitations of NPT in evaluating nasal response.

EAACI position paper on the clinical use of the bronchial allergen challenge: Unmet needs and research priorities

Allergic asthma (AA) is a common asthma phenotype, and its diagnosis requires both the demonstration of IgE-sensitization to aeroallergens and the causative role of this sensitization as a major driver of asthma symptoms. Therefore, a bronchial allergen challenge (BAC) would be occasionally required to identify AA patients among atopic asthmatics. Nevertheless, BAC is usually considered a research tool only, with existing protocols being tailored to mild asthmatics and research needs (eg long washout period for inhaled corticosteroids). Consequently, existing BAC protocols are not designed to be performed in moderate-to-severe asthmatics or in clinical practice. The correct diagnosis of AA might help select patients for immunomodulatory therapies. Allergen sublingual immunotherapy is now registered and recommended for controlled or partially controlled patients with house dust mite-driven AA and with FEV1 ≥ 70%. Allergen avoidance is costly and difficult to implement for the management of AA, so the proper selection of patients is also beneficial. In this position paper, the EAACI Task Force proposes a methodology for clinical BAC that would need to be validated in future studies. The clinical implementation of BAC could ultimately translate into a better phenotyping of asthmatics in real life, and into a more accurate selection of patients for long-term and costly management pathways.

Computational Repurposing of Drugs and Natural Products Against SARS-CoV-2 Main Protease (Mpro) as Potential COVID-19 Therapies

We urgently need to identify drugs to treat patients suffering from COVID-19 infection. Drugs rarely act at single molecular targets. Off-target effects are responsible for undesirable side effects and beneficial synergy between targets for specific illnesses. They have provided blockbuster drugs, e.g., Viagra for erectile dysfunction and Minoxidil for male pattern baldness. Existing drugs, those in clinical trials, and approved natural products constitute a rich resource of therapeutic agents that can be quickly repurposed, as they have already been assessed for safety in man. A key question is how to screen such compounds rapidly and efficiently for activity against new pandemic pathogens such as SARS-CoV-2. Here, we show how a fast and robust computational process can be used to screen large libraries of drugs and natural compounds to identify those that may inhibit the main protease of SARS-CoV-2. We show that the shortlist of 84 candidates with the strongest predicted binding affinities is highly enriched (≥25%) in compounds experimentally validated in vivo or in vitro to have activity in SARS-CoV-2. The top candidates also include drugs and natural products not previously identified as having COVID-19 activity, thereby providing leads for experimental validation. This predictive in silico screening pipeline will be valuable for repurposing existing drugs and discovering new drug candidates against other medically important pathogens relevant to future pandemics.

Efficacy and Safety of Subcutaneous Immunotherapy for Local Allergic Rhinitis: A Meta-Analysis of Randomized Controlled Trials

BACKGROUND

Subcutaneous immunotherapy (SCIT) has been used for treating local allergic rhinitis (LAR) patients. However, the clinical efficacy and safety were still questioned.

OBJECTIVE

This study was designed to estimate the efficacy and safety of SCIT for treating LAR patients through meta-analysis.

METHODS

We systemically searched MEDLINE, Cochrane Library, and Embase publications. Randomized, double-blind, clinical trials for the efficacy and safety of Allergen Immunotherapy (AIT) for LAR were included. A meta-analysis of 4 clinical endpoints (combined symptom and medication scores [CSMS], symptom scores [SS], medication scores [MS] and rhinoconjunctivitis quality of life questionnaire [RQLQ]) and adverse events (AEs)) was performed after bias and heterogeneity assessments. The immunologic response results were summarized.

RESULTS

Four RCTs with 134 patients were included. Four studies for analyzing primary outcomes (CSMS, SS, MS) and AEs, three for RQLQ results. The results indicated an important significant difference between SCIT and placebo groups, list as follows: CSMS (SMD = -2.42, 95% CI: -3.60 to -1.25, P < .0001), SS (SMD = -2.08, 95% CI -3.68 to -0.48, P = .01), MS (SMD = -1.43, 95% CI: -2.65 to -0.21, P = 0.02), RQLQ (SMD = -0.70, 95% CI -1.29 to -0.12, P = .02), Local AEs (RR = 4.13, 95% CI 1.08 to 15.77, P = .04). For immunologic response, significantly increased serum sIgG4 levels and improvements of allergen tolerance was observed after SCIT.

CONCLUSIONS

Our meta-analysis suggests that SCIT has a significant effect on improving symptoms and reducing medicine consumption for LAR patients. Larger and multicenter clinical trials are needed to clarify the safety and long-term efficacy.

Allergen-specific immunotherapy for local allergic rhinitis: a systematic review and meta-analysis

BACKGROUND

Local allergic rhinitis (LAR) is a phenotype of chronic rhinitis exhibiting a local Th2-driven inflammation without positive clinical markers of atopy. Immunomodulatory effects of allergen-specific immunotherapy (AIT) induce allergen-specific tolerance. However, AIT is not well-recognized as a treatment for LAR.

METHODOLOGY

Systematic search on six electronic databases and registries was performed. Experimental and observational studies of AIT for LAR patients were retrieved. The primary outcomes were symptom score, medication score, combined symptom medication score, and disease-specific quality of life. Secondary outcomes were serum specific(s) IgG4, sIgE, and adverse events.

RESULTS

Four double-blind randomized controlled trials (156 patients) from two research units assessed the effects of subcutaneous immunotherapy (SCIT). Compared with placebo, SCIT showed significant reductions in symptom score, medication score, combined symptom medication score, disease-specific quality of life, and an increase in serum sIgG4. There was no significant change in serum sIgE. Likewise, two observational studies (one using SCIT and one using sublingual immunotherapy) improved post-therapeutic symptom score. No studies assessed the effects after discontinuation of treatment. AIT was safe without serious adverse events.

CONCLUSION

AIT has beneficial effects and safe for LAR. Its effects are restricted to studies with short-term follow-up. AIT may be considered in LAR patients.

Local Respiratory Allergy: From Rhinitis Phenotype to Disease Spectrum

Local respiratory allergy (LRA) is defined by the negativity of atopy tests, a clinical history suggestive of airway allergy and a positive response to the nasal and/or bronchial allergen challenge. The clinical spectrum of LRA is comprised of three conditions: local allergic rhinitis (LAR) and local allergic asthma in non-atopic patients, and dual allergic rhinitis (coexistence of allergic rhinitis and LAR) in atopic individuals. LRA is an independent disease phenotype not progressing to atopy over time, but naturally evolving to the clinical worsening and the onset of comorbidities. Published data suggests that LRA is mediated through the mucosal synthesis of allergen-specific (s)IgE, which binds to FcϵRI on resident mast cells, and in >50% of cases traffics to the blood stream to sensitize circulating basophils. To date, 4 clinical trials have demonstrated the capacity of allergen immunotherapy (AIT) to decrease nasal, conjunctival and bronchial symptoms, to improve quality of life, to increase the threshold dose of allergen eliciting respiratory symptoms, and to induce serum sIgG₄ in LRA individuals. Collectively, these data indicate that local allergy is a relevant disease mechanisms in both atopic and non-atopic patients with airway diseases.

Diagnosis and treatment of non-allergic rhinitis: focus on immunologic mechanisms

INTRODUCTION

Non-allergic rhinitis (NAR) is a heterogeneous nasal disease with high global prevalence. NAR can be subclassified as nonallergic rhinitis with eosinophilia syndrome (NARES), vasomotor rhinitis (VMR), and local allergic rhinitis (LAR). Although the precise factors involved in the etiology of NAR are not clear, there is evidence that immunological factors play an important role in the pathogenesis of NAR. This review provides a comprehensive overview of the immunological and neurogenic mechanisms involved in the diagnosis and treatment of NAR.

AREAS COVERED

This review provides a comprehensive overview of the immunological basis of diagnostic and treatment strategies for NARES, VMR, and LAR. In particular, recently documented molecular and immunological mechanisms of NAR are discussed, which may help to better understand the mechanisms underlying the pathologies of the different endotypes of NAR.

EXPERT OPINION

An increasing number of studies investigating the pathogenesis of NAR suggest that the immunological mechanisms underlying the different subtypes of NAR vary greatly, and are still not fully understood to accurately diagnose these subtypes. Thus, further studies should focus on making diagnosis and treatment of NAR more precise, safe, and effective. A better understanding of the immunological mechanisms involved in NAR should help in the discovery of new diagnostic and treatment strategies.

Precision Medicine in House Dust Mite-Driven Allergic Asthma

House dust mites (HDMs) are the allergenic sources most frequently involved in airway allergy. Nevertheless, not every sensitized patient develops respiratory symptoms upon exposure to HDM, and there is a clinical need to differentiate allergic asthmatics (AAs) from atopic non-allergic asthmatics with HDM sensitization. This differentiation sometimes requires in vivo provocations like the bronchial allergen challenge (BAC). Interestingly, recent data demonstrate that non-atopic patients with asthma can also develop positive BAC results. This novel phenotype has been termed local allergic asthma (LAA). The interest in identifying the allergic triggers of asthma resides in the possibility of administering allergen immunotherapy (AIT). AIT is a disease-modifying intervention, the clinical benefit of which persists after therapy discontinuation. Recently, new modalities of sublingual tablets of HDM immunotherapy registered as pharmaceutical products (HDM-SLIT tablets) have become commercially available. HDM-SLIT tablets have demonstrated a robust effect over critical asthma parameters (dose of inhaled corticosteroids, exacerbations, and safety), thus being recommended by international guidelines for patients with HDM-driven AA. In this review, we will summarize the current knowledge on the phenotype and endotype of HDM-driven AA, and LAA, address the difficulties for BAC implementation in the clinic, and discuss the effects of AIT in AA and LAA.