Analysis of the immunoglobin E molecular sensitization profile in children with allergic asthma and predictive factors for the efficacy of allergy immunotherapy

Identification of rBlo t 41 with a chitin-binding type-2 domain: A novel major allergen from Blomia tropicalis

BACKGROUND

Blomia tropicalis (B. tropicalis) has been reported to impose an increased risk of allergic diseases. However, few characteristics of the unknown allergen components responsible for B. tropicalis allergy and clinical relevance have been fully identified.

METHODS

We synthesized and characterized the physicochemical properties and cross-reactivity of the newly discovered recombinant B. tropicalis group 41 allergen (rBlo t 41). Subsequently, sera were collected from 107 B. tropicalis allergic subjects to evaluate the prevalence of the rBlo t 41. Lastly, its allergenicity was tested in humans by basophil activation assays, and in mice by a model of allergic asthma.

RESULTS

The mature protein of rBlo t 41 was described as 104 amino acids long and 15.8 kDa, and its limited cross-reactivity was observed between allergens of house dust mites (HDM). Sensitization rate of rBlo t 41 (56.07 %) was lower than rBlo t 2 (76.29 %) and rBlo t 5 (69.07 %) in our study. Besides, rBlo t 41 elicited CD63 upregulation in basophils, whereas rBlo t 41-sensitized mice generated rBlo t 41-IgE and developed allergic airway inflammation after allergen exposure. Of note, component-based tests showed a high area under curve value (AUC = 0.75) of rBlo t 41, displaying its favorable diagnostic potential in B. tropicalis allergy.

CONCLUSIONS

rBlo t 41 was identified as a candidate novel major allergen with good diagnostic potential in B. tropicalis sensitization. Additionally, we provided strong evidence about rBlo t 41 on the clinically relevant manifestations in B. tropicalis allergies, conducive to facilitating the development of component-resolved diagnosis.

Detection of the peripheral blood antigens and clinical value in recurrent aphthous ulcer: A cross-section study

Abstract Background/purpose

Recurrent aphthous ulcer (RAU) is one of the most common diseases of oral mucosa, which is generally believed to be related to immunity, though the etiology is still unclear. It is suspected that allergies are directly related to RAU. So we sought to explore the relationship between hypersensitivity and RAU.

Materials and methods

40 RAU patients who were in ulceration period and 40 people who were in good health were selected from Jan 2016 to Feb 2017, matched in age and sex. The peripheral blood antigens of 40 RAU patients and 40 healthy people was tested, and serum specific IgE (sIgE) with 6 groups of antigens and total IgE (tIgE) analysis was performed to identify IgE-mediated allergic reaction possibly affecting RAU. We then investigated the food intolerance and IgG levels to discover the correlation between non-IgE mediated allergic reaction and RAU.

Results

The positive cases and rate of sIgE in RAU group was higher than that of control, but the difference was not statistically significant (P＞0.05). Positive grade of animal fur scraps (EX1), house dust mixed (HX2) and the serum tIgE concentration of the RAU group were significantly higher than the control group (P＜0.05).The number of food intolerance in RAU group was significantly higher than that in control group (P＜0.05).

Conclusion

Our findings suggested certain correlation between RAU and anaphylaxis. Daily contact allergens and food intolerance may be one of the causes of RAU. Moreover, this provides reference value for clinical diagnosis and treatment.

Effects of subcutaneous immunotherapy in allergic rhinitis children sensitive to dust mites

BACKGROUND

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.

OBJECTIVE

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

METHODS

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.

RESULTS

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.

CONCLUSION

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.

The Molecular Allergen Recognition Profile in China as Basis for Allergen-Specific Immunotherapy

Approximately 30% of the world population suffers from immunoglobulin-E (IgE)-mediated allergy. IgE-mediated allergy affects the respiratory tract, the skin and the gastrointestinal tract and may lead to life-threatening acute systemic manifestations such as anaphylactic shock. The symptoms of allergy are mediated by IgE-recognition of causative allergen molecules from different allergen sources. Today, molecular allergy diagnosis allows determining the disease-causing allergens to develop allergen-specific concepts for prevention and treatment of allergy. Allergen-specific preventive and therapeutic strategies include allergen avoidance, vaccination, and tolerance induction. The implementation of these preventive and therapeutic strategies requires a detailed knowledge of the relevant allergen molecules affecting a given population. China is the world´s most populous country with around 1.4 billion inhabitants and an estimated number of more than 400 million allergic patients. Research in allergy in China has dramatically increased in the last decade. We summarize in this review article what is known about the dominating allergen sources and allergen molecules in China and what further investigations could be performed to draw a molecular map of IgE sensitization for China as a basis for the implementation of systematic and rational allergen-specific preventive and therapeutic strategies to combat allergic diseases in this country.

Correlation study of cytokine levels in alveolar lavage fluid with exhaled nitric oxide and lung function in children with bronchial asthma

BACKGROUND

The associations between cytokines in the bronchoalveolar lavage fluid (BALF), lung cytokine expression, fractional exhaled nitric oxide (FeNO) and pulmonary function test results in pediatric asthmatics have not been extensively characterized. This study sought to explore correlations between cytokines BALF, FeNO, and pulmonary function test results.

METHODS

From October 2018 to October 2020, a prospective study was conducted on 42 children with asthma and 17 children with pulmonary foreign bodies that required bronchoscopy. Pulmonary function tests and FeNO tests were performed on all patients. Patients were divided into a high FeNO group or low FeNO group based on their FeNO results. Interleukin (IL)-4, IL-5, IL-6, IL-8, IL-13, and IL-17 in the BALF were measured by enzyme-linked immunosorbent assays. Pearson correlations were used to assess the correlations between the cytokines in BALF, the pulmonary function test results, and the FeNO results. Pearson correlation was used to calculate the correlation coefficient "r" among alveolar lavage fluid cytokines, lung function, and FeNO. Receiver operating characteristic (ROC) curves were used to determine the area under the curve (AUC), sensitivity, and specificity of BALF cytokines for the high and low FeNO groups.

RESULTS

IL-4, IL-5, IL-6, IL-8, IL-13, and IL-17 in BALF were significantly correlated with FeNO, but were not significantly correlated with the pulmonary function test results. Cytokine IL-4, IL-5, IL-6, IL-8, IL-13, and IL-17 in BALF were significantly different in the high FeNO, low FeNO, and control groups (all P<0.05). The AUCs for differentiating between low and high FeNO based on BALF cytokines ranged from 0.72 to 0.95. The sensitivity and specificity for discriminating between low and high FeNO based on IL-5 and IL-13 reached 95.7% and 100%, respectively.

CONCLUSIONS

The cytokine levels of the BALF of children with asthma were significantly elevated, correlated with FeNO, and can be used evaluate airway inflammation in children with asthma.