Sensitization profiles of aeroallergens among allergic rhinitis patients in China: A 13-year multicenter retrospective study

Chinese expert consensus on allergen component resolved diagnosis

BACKGROUND

Allergen component resolved diagnosis (CRD) is a method for identifying specific protein molecules that cause hypersensitivity. Unlike traditional methods that use crude allergen extracts containing multiple component species, CRD focuses on individual allergen protein molecules for more precise diagnosis. The World Allergy Organization (WAO) recommends CRD as a supplement to clinical history and allergen extract testing, and in some cases, it can replace crude extract tests.

METHODS

CRD involves the use of natural or recombinant proteins to detect specific IgE antibodies directed at individual allergenic components. This method allows for a more detailed analysis of a patient's allergic response compared to the use of whole allergen extracts. The Allergy Prevention and Control Specialty Committee of the Chinese Preventive Medicine Association, in collaboration with multidisciplinary experts, developed an expert consensus that incorporates the consensus of the European Academy of Allergy and Clinical Immunology (EAACI), WAO, and important domestic literature on CRD in recent years.

RESULTS

The consensus aims to standardize the algorithm of allergen diagnosis and provides a reference for clinical practice. It also offers guidance for clinicians on the common protein families identified by CRD, the scenarios where CRD is applicable, and the significance of detecting common allergen components.

CONCLUSIONS

Despite its potential, CRD is not widely used in clinical practice in China due to the lack of allergen component reagents and a general unawareness among clinicians about CRD's application and interpretation of test results. The expert consensus developed by the Chinese Preventive Medicine Association aims to address this gap and enhance the clinical application of CRD in China.

Augmented type 2 inflammatory response in allergic rhinitis patients experiencing systemic reactions to house dust mite subcutaneous immunotherapy

BACKGROUND

Subcutaneous immunotherapy (SCIT) can induce systemic reactions (SRs) in certain patients, but the underlying mechanisms remain to be fully elucidated.

METHODS

AR patients who were undergoing standardized HDM SCIT (Alutard, ALK) between 2018 and 2022 were screened. Those who experienced two consecutive SRs were included in the study group. A control group was established, matched 1:1 by gender, age, and disease duration with the study group, who did not experience SRs during SCIT. Clinical and immunological parameters were recorded and analyzed both before SCIT and after 1 year of treatment.

RESULTS

A total of 161 patients were included, with 79 (49.07%) in the study group. The study group had a higher proportion of AR combined asthma (26.8% vs. 51.8%, p < 0.001) and higher levels of sIgE to HDM and HDM components (all p < .001). Serum IL-4 and IL-13 levels in the study group were higher than those in the control group (p < .05). The study group received a lower maintenance dosage of HDM extracts injections than control group due to SRs (50000SQ vs. 100000SQ, p < .05). After 1 year of SCIT, the VAS score, the lung function parameters of asthmatic patients over 14 years old significantly improved in both groups (all p < .05). After a 7-day exposure to 20 μg/mL HDM extracts, the percentages of Th1, Th17, Tfh10, and Th17.1 in PBMCs decreased, while the Tfh13 cells significantly increased in the study group (p < .05).

CONCLUSION

The type 2 inflammatory response is augmented in HDM-induced AR patients who experienced SRs during SCIT. Despite this, SCIT remains effective in these patients when administered with low-dosage allergen extracts.

Alternaria Allergy and Immunotherapy

BACKGROUND

Allergen immunotherapy (AIT) is the only known causative treatment for Alternaria allergy, but the difficulty in standardizing Alternaria extracts hampers its effectiveness and safety.

SUMMARY

Alternaria, a potent airborne allergen, has a high sensitization rate and is known to trigger the onset and exacerbation of respiratory allergies, even inducing fungal food allergy syndrome in some cases. It can trigger a type 2 inflammatory response, leading to an increase in the secretion of type 2 inflammatory cytokines and eosinophils, which are the culprits behind allergic symptoms. Diagnosing Alternaria allergy is a multistep process, involving a careful examination of clinical symptoms, medical history, skin prick tests, serum-specific IgE detection, or provocation tests. Alt a1, the major component of Alternaria, is a vital player in diagnosing Alternaria allergy through component-resolved diagnosis. Interestingly, Alternaria can reduce the protein activity of other allergens like pollen and cat dander when mixed with them. In order to solve the problems of standardization, efficacy and safety of traditional Alternaria AIT, novel AIT methods targeting Alt a1 and innovative vaccines such as epitope, DNA, and mRNA vaccines seem promising in bypassing the standardization issue of Alternaria extracts. But these studies are in early stages, and most researches are still focused on animal models, calling for more evidence to validate their use in humans.

KEY MESSAGES

This review delves into the various aspects of Alternaria allergy, including characteristics, epidemiology, immune mechanisms, diagnosis, clinical manifestations, and the application and limitations of Alternaria AIT, aiming to provide a foundation for the management of patients with Alternaria allergy.

Comparison of the therapeutic effects of medication therapy, specific immunotherapy and anti-IgE (Omalizumab) in patients with hay fever

Background

Hay fever, characterized by seasonal allergic reactions, poses a significant health challenge. Existing therapies encompass standard drug regimens, biological agents, and specific immunotherapy. This study aims to assess and compare the effectiveness of anti-IgE (omalizumab), medication therapy, and subcutaneous immunotherapy (SCIT) for hay fever.

Methods

Conducted as a retrospective cohort study, this research involved 98 outpatient hay fever patients who underwent routine medication, omalizumab treatment, or SCIT before the onset of the spring pollen season. A follow-up was performed one month after the start of the pollen season. The comprehensive symptoms and drug scores were used to evaluate patients with different intervention methods, facilitating a comparative analysis of therapeutic outcomes.

Results

Compared with before treatment, the symptoms of patients treated with the three methods were all significantly relieved, and the medication score were significantly reduced. Patients treated with omalizumab demonstrated higher symptoms and medication scores than SCIT group before treatment, but similar scores after treatment, which were both lower than medicine treatment group. After treatment with omalizumab or SCIT, patients in both groups had significantly lower medication scores than the medication group and were close to no longer using medication for symptom relief. The mountain juniper-sIgE was significantly higher after treatment than before treatment in both medicine treatment group and omalizumab treatment group.

Conclusion

Omalizumab and SCIT offer superior effects than medication therapy in hay fever patients.

Allergen immunotherapy in China

Allergen immunotherapy (AIT) is an etiological treatment strategy that involves administering escalating doses of clinically relevant allergens to desensitize the immune system. It has shown encouraging results in reducing allergy symptoms and enhancing patients' quality of life. In this review, we offer a thorough overview of AIT in China, examining its efficacy, safety, current practices, and prospects. We further underscore the progress made in AIT research and clinical applications, as well as the distinct challenges and opportunities that China faces in this area.

Serum exosome-derived miR-146a-3p promotes macrophage M2 polarization in allergic rhinitis by targeting VAV3 via PI3K/AKT/mTOR pathway

BACKGROUND

Our previous study showed that miR-146a-3p was elevated in serum exosomes of allergic rhinitis (AR) patients, but the underlying mechanisms were unclarified. This study was to investigate the impact of exosome-derived miR-146a-3p on macrophage polarization in the pathology of AR.

METHOD

We detected the expression of miR-146a-3p in nasal tissues of AR patients and healthy controls (HCs), and investigated its correlation with macrophage polarization markers. The impact of miR-146a-3p derived from AR serum exosomes on macrophage polarization was examined. Transcriptome sequencing was performed on macrophages treated with a miR-146a-3p inhibitor, and target genes of miR-146a-3p were explored through a combination of bioinformatics analysis and experimental validation.

RESULTS

The expressions of miR-146a-3p and macrophage polarization markers were increased in the AR nasal tissues, and a positive association was observed between the expressions of miR-146a-3p and the levels of CD163 and CD206. The AR serum exosomes could be uptake by macrophages, and promote M2 polarization and cytokine secretions. Mechanistically, miR-146a-3p regulation could impact both macrophage M2 polarization and cytokine secretion. Inhibition of miR-146a-3p altered the gene transcriptions within macrophages. Bioinformatics analysis and clinical pathological specimen research confirmed that VAV3 was a target gene of miR-146a-3p, and it exerted a detrimental effect on macrophage M2 polarization via the PI3K/AKT/mTOR pathway. Functional recovery experiments and dual-luciferase reporter gene assays confirmed that miR-146a-3p could selectively target and inhibit the expression of VAV3, thereby promoting macrophage M2 polarization through the PI3K/AKT/mTOR pathway.

CONCLUSION

Serum exosome-derived miR-146a-3p facilitated macrophage M2 polarization in AR by targeting VAV3 through the PI3K/AKT/mTOR pathway. These findings implied that miR-146a-3p and VAV3 could serve as potential targets for the development of novel therapeutic strategies in AR management.