Allergic asthma is linked to impaired bronchial epithelial secretion of interferons (IFNs) which may be causally linked with the increased risk of viral exacerbations. We have previously shown that allergen immunotherapy (AIT) effectively reduces asthma exacerbations and prevents respiratory infections requiring antibiotics; however, whether AIT alters antiviral immunity is still unknown.

To investigate the effect of house dust mite sublingual allergen immunotherapy (HDM-SLIT) on the bronchial epithelial antiviral and inflammatory responses in patients with allergic asthma.

In this double blind randomized controlled trial (VITAL), adult patients with HDM allergic asthma received HDM-SLIT 12-SQ or placebo for 24-weeks. Bronchoscopy was performed at baseline and at week-24 which included sampling for human bronchial epithelial cells (HBECs). HBECs were cultured at baseline and at week-24 and stimulated with the viral mimic poly(I:C). mRNA expression was quantified by RT-qPCR and protein levels were measured by multiplex ELISA.

Thirty-nine patients were randomized to HDM-SLIT (n=20) or placebo (n=19). HDM-SLIT resulted in increased poly(I:C)-induced expression of IFN-β, both at gene (p=.009) and protein (p=0.02) level. IFN-λ gene expression was also increased (p=0.03), whereas IL-33 tended to be decreased (p=0.09). On the other hand, pro-inflammatory cytokines IL-6 (p=.009) and TNF-α (p=0.08) increased compared with baseline in HDM-SLIT group. There was no significant change in TSLP, IL-4, IL-13, and IL-10.

HDM-SLIT improves bronchial epithelial antiviral resistance to viral infection. These results potentially explain the efficacy of HDM SLIT reducing exacerbations in allergic asthma.

The immunological effect of allergen-specific immunotherapy is well documented, but few studies have examined the long-term effects of pollen subcutaneous immunotherapy (SCIT) on health-related quality of life (HRQoL) in children and adolescents. Therefore, the aims of this study were to evaluate the effect of pollen SCIT on HRQoL and to assess the association between HRQoL and symptoms among children and adolescents with allergic rhinoconjunctivitisin a 3 year follow-up.

A prospective cohort study was conducted at a paediatric clinic in Sweden, including 158 children (5-16 years) on SCIT (birch and/or grass). Health-related quality of life, measured with DISABKIDS, symptom scores and allergen-specific IgE and IgG4 antibodies (blood test), were assessed at start, and after 1, 2 and 3 years of treatment. ANOVA and t-test were used to analyse differences over time, between groups and linear mixed model for the association between HRQoL and influencing factors.

After 1 year of pollen SCIT, HRQoL improved from 79.5 to 85.1 (p < 0.001), and the improvements were maintained (mean 1 years, 84.8, 3 years 87.2). Symptom scores decreased after 1 year, mean 19.9 to 11.5 (p < 0.001) and were maintained for year two (11.9) and year three (10.3). The proportion of children with severe or very severe symptoms decreased from 35.6% to 4.5% after 1 year of SCIT. Health related quality of life was associated with symptoms at all measured timepoints (p = 0.001-0.031); higher symptom scores were associated with lower perceived HRQoL. Allergen-specific IgE antibodies decreased, birch from 151.0 to 76.8 kU/L (p < 0.001), and IgG4 antibodies increased, birch from 2.2 to 17.6 g/L (p < 0.001), grass from 0.5 to 14.3 g/L (p < 0.001), during the study period.

After 1 year of pollen SCIT, HRQoL improved, and symptoms decreased; these changes were maintained during the study period. The proportion of severe and very severe symptoms significantly decreased.

Type 2 innate lymphoid cells (ILC2) are upregulated in childhood allergic rhinitis (AR) and are associated with AR severity. This study aimed to investigate changes in the ILC2 milieu in pediatric patients with AR after sublingual immunotherapy (SLIT).

Forty- pediatric patients with AR received house dust mite (HDM) allergen extract for SLIT group and thirty pediatric patients received placebo in the study, respectively. The levels of ILC2, ILC2-related cytokines (IL-5/IL-13) and their transcription factors (GATA binding protein 3, retinoic acid-related orphan receptor α) in the circulation were assessed after 1- and 2-year SLIT. Moreover, peripheral blood mononuclear cells (PBMCs) in patients were prepared and stimulated by recombinant thymic stromal lymphopoietin, IL-25, and IL-33 after 2-year SLIT. Subsequently, the levels of ILC2, IL-5, and IL-13 were tested.

The frequency of ILC2 and the levels of their transcription factors in the circulation were significantly decreased after SLIT in the SLIT group. The levels of ILC2-related cytokines in the SLIT group showed the same trend. The frequency of ILC2 was positively correlated with transcription factors and cytokines after SLIT. SLIT was observed to reduce the ability of HDM sensitization to generate the ILC2 milieu in PBMCs.

Changes in the ILC2 milieu may be correlated with the curative effect and immune regulation function of SLIT. Our results suggested that the regulatory effect on ILC2 is part of the therapeutic mechanism of SLIT.

Sublingual immunotherapy (SLIT) is an effective treatment for allergic rhinitis (AR), but its efficacy is variable among individuals. This study aimed to characterize serum exosome-derived microRNAs (miRNAs) and evaluate their abilities in predicting the efficacy of SLIT in AR.

RNA sequencing was performed to explore differentially expressed exosomal miRNAs in serum exosomes between AR patients and healthy controls (HCs). Sequencing analysis results were verified in an independent cohort, and the correlations between the levels of exosome-derived miRNAs and disease severity were evaluated. The most promising miRNAs were further tested in two AR cohorts treated with SLIT to assess their abilities in predicting short and long term efficacy, respectively.

The exosome-derived miRNAs profiling in the AR group was significantly different from the HC group, and differentially expressed genes were enriched and clustered in pathways such as PI3K-Akt and ErbB signalling pathways. The top three most significant miRNAs were verified by reverse transcription polymerase chain reaction (qRT-PCR), and results showed that miR-146a-3p levels were significantly elevated in the AR group and correlated with the total and specific gE levels, the visual analogue scale of the total nasal symptom score (all p < 0.05). Further data in the first validation cohort suggested that miR-146a-3p levels were significantly downregulated in the effective group, and logistic regression showed that miR-146a-3p levels were associated with the short-term efficacy of SLIT(p < 0.05). The receiver operating characteristic (ROC) curve showed that miR-146a-3p could early predict SLIT efficacy (AUC = 0.669, p = 0.047). In the second validation cohort, miR-146a-3p levels were also decreased in the effective group and the ROC curve further confirmed its reliable accuracy in predicting the long-term efficacy of SLIT in AR patients (AUC = 0.749, p < 0.001).

Serum exosome-derived miRNAs may be involved in the development of AR and associated with its disease severity. Serum exosome-derived miR-146a-3p seems to be a novel biomarker for predicting the short and long-term efficacies of SLIT in AR patients.

Subcutaneous immunotherapy (SCIT) is now the only treatment that can modify the natural course of allergic rhinitis (AR). However, not all children with AR benefit from SCIT.

To evaluate the efficacy of SCIT in dust-mites-induced AR children and explore correlative factors predicting treatment response to SCIT.

225 children aged 4-17 years old with AR were recruited from January 2016 to September 2019, and monitored at baseline, 4, 12, and 24 months after the start of SCIT treatment. The visual-analogue-score (VAS) was used to assess the clinical symptoms. Multivariate binary logistic regression analyses and receiver operating characteristic curves were used to explore correlative factors in predicting the efficacy of SCIT.

The significant declines in VAS started after 4 months of SCIT and continued to improve throughout the study compared with baseline. An increase in children's age (OR=0.688, 95%CI: 0.479-0.988) and those with allergic history (OR=0.097, 95%CI: 0.009-1.095) were negatively associated with the risk of poor efficacy. Polysensitized children were more likely to suffer poor efficacy (OR=15.511 95%CI: 1.319 182.355). The clinical response at month 4 (r=0.707) and month 12 (r=0.925) was related to that at month 24. The area under the curve (AUC) for improvement at month 4 and month 12 was 0.746 and 0.860, respectively.

Our study confirmed the clinical efficacy of SCIT in AR children. Children with younger age, negative allergic history, and multiple allergens may predict a worse efficacy. The onset of action and the clinical response to SCIT in the second year can be predicted as early as by month 4.

Allergic rhinoconjunctivitis(ARC) is a common chronic inflammatory disease. Numerous studies on the treatment of ARC have been published. By contrast, there are few bibliometric studies on immunotherapy for ARC. The purpose of this article is to describe the current treatments for ARC and to identify the trends in immunotherapy for ARC.

Publications were searched from the Web of Science (WOS) Core Collection on April 25, 2022. CiteSpace and Microsoft Excel software were used for further bibliometric analysis.

A total of 969 publications on immunotherapy for ARC in English were retrieved. The number of relevant publications has been continuously increasing over the past 20 years, with many of the publications coming from Germany and the United States of America. In terms of institutions, the ALK Company in Denmark, Imperial College London in United Kingdom, and Charite-Universitatsmedizin Berlin in Germany published the most articles on immunotherapy for ARC. Meanwhile, Allergy and Journal of Allergy and Clinical Immunology published the most number of studies, and Oliver Pfaar from Germany authored the most number of articles. "Subcutaneous immunotherapy," "international consensus," "allergen immunotherapy," and "recommendation" were the most popular subjects. Thus, directions in research can be predicted as studies regarding mechanisms of ARC, clinical trials, and extracts have reported high-quality results.

Over the past 20 years, the overall quality of research on immunotherapy for ARC has gradually improved, allowing the introduction of specific and targeted treatment. Currently, the main focus of ARC research is the novel routes of drug delivery and combined treatment with biological agents.

In IgE-mediated food allergies, exposure to the allergen activates systemic allergic responses. Oral immunotherapy (OIT) treats food allergies through incremental increases in oral allergen exposure. However, OIT only induces sustained clinical tolerance and decreased basophil sensitivity in a subset of individuals despite increases in circulating allergen-specific IgG in all treated individuals. Therefore, we examined the allergen-specific antibodies from 2 OIT cohorts of patients with sustained and transient responses. Here, we compared antibodies from individuals with sustained or transient responses and discovered specific tolerance-associated conformational epitopes of the immunodominant allergen Ara h 2 recognized by neutralizing antibodies. First, we identified what we believe to be previously unknown conformational, intrahelical epitopes using x-ray crystallography with recombinant antibodies. We then identified epitopes only recognized in sustained tolerance. Finally, antibodies recognizing toleranceassociated epitopes effectively neutralized allergen to suppress IgE-mediated effector cell activation. Our results demonstrate the molecular basis of antibody-mediated protection in IgE-mediated food allergy, by defining how these antibodies disrupt IgE-allergen interactions to prevent allergic reactions. Our approach to studying the structural and functional basis for neutralizing antibodies demonstrates the clinical relevance of specific antibody clones in antibody-mediated tolerance. We anticipate that our findings will form the foundation for treatments of peanut allergy using neutralizing antibodies and hypoallergens.

To analyze various risk factors including causes that may lead to adverse reactions, especially systemic adverse reactions（SRs）, before and after mite allergen subcutaneous immunotherapy (SCIT), so as to provide real-world reference data for further improving the safety of mite allergen SCIT.

The local adverse reactions（LRs）and SRs of 230 patients with allergic rhinitis and/or asthma who received SCIT in Weifang people's hospital were analyzed retrospectively. The data of patient characteristics, drug factors and environmental elements of adverse reactions were collected and statistically analyzed.

There were 28 cases (12.2%) of SRs in 230 patients. All the patients received a total of 7515 injections and 37 SRs (0.49%) were observed. 32.4% (12/37) of SRs could identify their external and subjective triggers. SRs patients had higher 2-year SCIT compliance than no-SRs patients (p = 0.026). The prevalence of SRs in SCIT patients with atopic dermatitis or simple allergic asthma are no statistical significance (P = 0.111).

The incidence of SRs in this study is within an ideal range. Through professional patient education and pre injection risk factor assessment, Compliance is still wellcontrolled and guaranteed although SRs occurred.

Allergic rhinitis (AR) is a common upper airways inflammatory condition especially in paediatric population; its burden potentially impacts on quality of life, quality of sleep and daily performance, which can be difficult to perceive but not less relevant in the middle-long term. The present review aims to provide an updated overview on AR epidemiology, diagnosis and with a special focus on its connections with bronchial asthma. In fact, when considering asthmatic pediatricpopulation, AR is probably the most important risk factor for asthma onset and the most impactful extra bronchial determinant of asthma control. Under this perspective, allergen immunotherapy (AIT) should always be considered in the light of a precision medicine approach. In fact, AIT does represent a unique opportunity to specifically interfere with AR immunological background, improve both AR and bronchial asthma control and prevent allergic disease evolution. Verifying the patient's eligibility to that option should be considered as a priority for every physician managing children suffering from AR, especially when associated with bronchial asthma.

To develop a questionnaire and a scoring system for evaluating physicians' knowledge of allergen immunotherapy (AIT).

Questionnaire was designed using the Questionnaire Star tool. A total of 1024 physicians were assessed, and based on the score divided into accurate judgment and inaccurate judgment groups. Statistical analysis was done, and counting data were expressed as frequencies and percentage values. Chi-square test and multi-factor logistic analysis were used to determine influencing factors on the indications for AIT.

Physician's age, grade of the hospital, and pediatric specialty influenced the accurate judgment of AIT indication after adjustment for independent variables (P < 0.05). In all, 80.5% physicians exercised accurate assessment for allergic rhinitis. Allergic conjunctivitis was judged accurately by 47.0% physicians. Bronchial asthma was judged accurately by 71.0% physicians, and atopic dermatitis by 61.3% physicians, with a higher accuracy rate for pediatricians than nonpediatriciansfor all the mentioned conditions (P 0.05).

The results of our study demonstrated a high accuracy judgment rate among clinicians for rhinitis, asthma, and dermatitis, and a low accuracy rate for desensitization of healthy people with allergic conjunctivitis, food allergies, and allergen sensitization.