Common Allergens and Immune Responses Associated with Allergic Rhinitis in China

Prevalence of aeroallergen sensitization in children in Northern China

OBJECTIVE

This study aimed to analyze the sensitization rate of different aeroallergens in children of different age, sex, and disease groups, describe the changing trend of different aeroallergens in different ages, and analyze the sensitization risk factors for asthma.

METHODS

Children (<18 years old) with suspected atopic diseases who visited the Department of Allergy of Children's Hospital Affiliated to Capital Institute of Pediatrics and underwent a skin prick test (SPT) were retrospectively enrolled from January 2019 to November 2021.

RESULTS

A total of 5465 patients (3514 boys, 1951 girls; mean age, 7 ± 3 years) were enrolled. Of them, 3703 patients (67.8%) were sensitized to at least one aeroallergen. Before 4 years of age, mold was the most prevalent aeroallergen (103/380 [27.1%]), whereas after 4 years of age, weed pollen was the most prevalent aeroallergen. After 6 years of age, tree pollen became the second most prevalent aeroallergen. After 12 years of age, the sensitization rate of indoor aeroallergens was lower than that of outdoor aeroallergens. Logistic regression showed that sensitization to mold (odds ratio [OR]:1.4, 95% confidence interval (CI): 1.2-1.7, p < 0.001), animal dander (OR: 1.6, 95% CI: 1.4-1.9, p < 0.001), and polysensitization (OR: 1.4, 95% CI: 1.0-1.8, p = 0.038) were potential sensitization risk factors for asthma.

CONCLUSIONS

Mold is an important allergen in early life. Different kinds of allergens affect different age groups. Patients who are sensitized to mold or animal dander or experience polysensitization should be carefully monitored for asthma risk.

Multicenter study of seasonal and regional airborne allergens in Chinese preschoolers with allergic rhinitis

This study is nationwide multicenter epidemiological research, aimed at investigating the distribution changes and seasonal patterns of various airborne allergens among preschool children with allergic rhinitis (AR) in different regions of China, and analyzing the clinical correlation between sensitization to various airborne allergens and AR symptoms in children. Information on children was collected through standard questionnaires, and total IgE (tIgE) and specific IgE (sIgE) for 11 inhalant allergens were tested. The results showed that dust mites are the primary allergens for preschool AR children (39%). Among pollen allergens, Amb a had the highest positivity rate (8.1%), followed by Art v (7.8%). The sensitization rates for two mites peaked in May (46.9% and 40.6%). Art v peaked in August (21.5%), while Amb a had peaks in May (12.7%) and August (17.8%). The sensitization peaks for various tree pollens mainly occurred in August. In the Eastern monsoon region, the sensitization rate to mites was significantly higher than in the Northwest arid and semi-arid regions; whereas, for pollen allergens, the sensitization rates to Amb a, Pla a, Pin a, Pop d, and Bet v were significantly higher in the Northwest arid and semi-arid regions than in the Eastern monsoon region. The correlation among various tree pollens, specifically between Pla a, Pin r, Pop d, and Bet v was strong (0.63 ~ 0.79), with a cross-overlapping percentage of 53.9%. Children with multiple pollen sensitizations had higher cumulative nasal symptom scores than those negative for pollen (P < 0.01). Children with only pollen sensitization had higher cumulative rhinitis symptom scores than the all-negative group (P < 0.0001) and the mite-only sensitization group [P < 0.05], while the mite-only sensitization group also had higher scores than the all-negative group [P < 0.05], and the group sensitized to both pollen and mites had lower scores than the pollen-only group [P < 0.05]. This study indicates that sensitization to mites and grass pollens exhibits significant regional differences, with grass pollen allergies primarily occurring in autumn, sensitization to pollens in general exhibits a pronounced seasonal pattern. Moreover, pollen sensitization aggravates nasal and ocular symptoms in AR children.

Neuroimmune communication in allergic rhinitis

The prevalence rate of allergic rhinitis (AR) is high worldwide. The inhalation of allergens induces AR, which is an immunoglobulin E-mediated and type 2 inflammation-driven disease. Recently, the role of neuroimmune communication in AR pathogenesis has piqued the interest of the scientific community. Various neuropeptides, such as substance P (SP), vasoactive intestinal peptide (VIP), calcitonin gene-related peptide (CGRP), nerve growth factor (NGF), and neuromedin U (NMU), released via "axon reflexes" or "central sensitization" exert regulatory effects on immune cells to elicit "neurogenic inflammation," which contributes to nasal hyperresponsiveness (NHR) in AR. Additionally, neuropeptides can be produced in immune cells. The frequent colocalization of immune and neuronal cells at certain anatomical regions promotes the establishment of neuroimmune cell units, such as nerve-mast cells, nerve-type 2 innate lymphoid cells (ILC2s), nerve-eosinophils and nerve-basophils units. Receptors expressed both on immune cells and neurons, such as TRPV1, TRPA1, and Mas-related G protein-coupled receptor X2 (MRGPRX2) mediate AR pathogenesis. This review focused on elucidating the mechanisms underlying neuroimmune communication in AR.

Traditional Chinese Medicine constitution among patients with allergic rhinitis and its correlation with anxiety and depression

OBJECTIVE

To preliminary investigate the distribution of Traditional Chinese Medicine (TCM) constitution among patients with allergic rhinitis (AR) and reveal the related factors with anxiety and depression.

METHODS

Between July 2020 and June 2021, specialist doctor recruited AR patients in Beijing and Shanghai. A total of 630 patients admitted to participate in the survey, and 516 (81.9%) (male 54.3%, female 45.7%) participants completed the questionnaires. Three scales including Constitution in Chinese Medicine Questionnaire (CCMQ), Generalized Anxiety Disorder Questionnaire (GAD-7) and The Patient Health Queationaire-9 (PHQ-9) were applied. The χ2 and the Fisher's exact test were used to evaluate the classification data, multivariate logistic regression was used to explore the related factors of anxiety and depression.

RESULTS

According to 516 AR patients, the most commonly first-constitution was Yang-deficiency (22.1%) and frequent of all constitutions was inherited-special (21.6%). One third of AR patients (33.5%) suffered from anxiety, nearly half of AR patients (46.5%) were found to be depressive. Inherited-special (27.7%) was the most common constitution in patients with anxiety whereas Yang-deficiency (26.7%) was most common constitution in patients with depression. Sex, duration of symptoms, balanced, Qi-deficiency, phlegm-dampness, Qi-stagnation, and inherited-special constitutions were related with anxiety; Sex, income, duration of symptoms, balanced, Qi-deficiency, Yang-deficiency, phlegm-dampness, Qi-stagnation, and inherited-special constitutions were related with depression.

CONCLUSIONS

According to our study, the commonly constitution types of AR were Yang-deficiency and inherited-special. We found that the prevalence value of anxiety and depression were high. People with Qi-deficiency, phlegm-dampness, Qi-stagnation, and inherited-special constitutions were more likely to have mental problems than the others. Controlling these influential factors might be beneficial for clinical health management of AR patients, and the government should apply appropriate mental health treatment services to offer psychiatric support.