Positive association between HLA-DRB1*07 and specific IgE responses to purified major allergens of D. pteronyssinus (Der p 1 and Der p 2)

Allergen Differences and Correlation Analysis in Siblings Diagnosed with Respiratory Allergic Diseases

INTRODUCTION

Many parents of children with allergies are worried whether their subsequent children will have allergic reactions to the same allergens. Much of the current research on sibling allergens has been focused on twins; however, in real life, very few children are twins. Our study provides an opportunity to initially explore the sensitivity to allergens in siblings diagnosed with respiratory allergic diseases.

METHODS

Siblings diagnosed with bronchial asthma and/or allergic rhinitis in the Outpatient Department of Allergy Department of Yantai Yuhuangding Hospital from January 2018 to December 2021 were selected. The siblings were divided into elder group and younger group. Data of gender, age, feeding history, serum total IgE (TIgE), absolute eosinophil counts, and allergen-specific IgE (sIgE) were collected and analyzed. The sIgEs of allergens were divided into six categories and analyzed.

RESULTS

A total of 98 sibling pairs of patients were included in this study. There were no differences in the positive rates of the different types of allergens, TIgE values, and the absolute eosinophil values between the elder and younger groups and between different genders. Logistic regression analysis indicated that the elder siblings allergic to dust mites, fungi, weed pollens, or food had a statistically significant increased risk of having their younger sibling sensitive to these types of allergens (all p <0.05), and the risk of allergy to dust mites, weed pollens, and tree pollens of younger group increased with age (all p <0.05). Except for the sIgE values of dust mites, the sIgE values of the other allergens were significantly correlated between the two groups (all p <0.05).

CONCLUSION

The positive rates of different allergens were similar between siblings. Elder siblings with dust mites, fungi, weed pollen, or food allergen positivity will have younger siblings sensitive to the same types of allergens.

Meta-Analysis of the Association Study between Allergic Rhinitis and HLA-II Gene (DQB1) in Northern China

Objective

To explore the association between allergic rhinitis and HLA-II gene (DQB1) in the Chinese population.

Methods

The literature studies related to allergic rhinitis and HLA-II gene (DQB1) in the Chinese population were searched, and those that did not meet the requirements were excluded. The consistency was checked by using RevMan 4.1 software.

Results

The HLA-II gene (DQB1) may be a risk gene for patients with allergic rhinitis in Northern China (P < 0.01).

Conclusion

Allergic rhinitis in China was associated with the HLA-II gene (DQB1).

International consensus (ICON) on: clinical consequences of mite hypersensitivity, a global problem

Since mite allergens are the most relevant inducers of allergic diseases worldwide, resulting in significant morbidity and increased burden on health services, the International Collaboration in Asthma, Allergy and Immunology (iCAALL), formed by the American Academy of Allergy, Asthma and Immunology (AAAAI), the American College of Allergy, Asthma and Immunology (ACAAI), the European Academy of Allergy and Clinical Immunology (EAACI), and the World Allergy Organization (WAO), has proposed to issue an International Consensus (ICON) on the clinical consequences of mite hypersensitivity. The objectives of this document are to highlight aspects of mite biology that are clinically relevant, to update the current knowledge on mite allergens, routes of sensitization, the genetics of IgE responses to mites, the epidemiologic aspects of mite hypersensitivity, the clinical pictures induced by mites, the diagnosis, specific immunotherapeutic approaches, and prevention.

The HLA-DRB1 Polymorphism is Associated With Atopic Dermatitis, but not Egg Allergy in Korean Children

Purpose

We investigated whether particular HLA-DRB1 polymorphisms contribute to egg allergy development in Korean children with atopic dermatitis (AD).

Methods

HLA-DRB1 alleles were determined by PCR-sequence-specific oligonucleotide (SSO) and PCR-single-strand conformation polymorphism (SSCP) methods in 185 patients with AD and 109 normal control (NC) subjects. AD patients were divided into two groups: 1) AD with egg allergy, consisting of 96 patients with egg allergies as determined by egg-specific immunoglobulin E (IgE) reactivity; and 2) AD without egg allergy, consisting of 89 patients without egg allergies. HLA-DRB1 alleles were classified into functional groups (A, De, Dr, E, Q, R, a). HLA-DRB1 phenotype and functional group frequencies in the AD, AD with egg allergy, and AD without egg allergy groups were compared with those in the NC group.

Results

The frequency of DRB1^*08:02 was decreased in the AD with egg allergy group compared with the AD without egg allergy group (2.1% vs. 10.1%, P=0.021), and DRB1^*15:01 was increased in the AD with egg allergy group compared with the AD without egg allergy group (22.9% vs. 11.2%, P=0.036). However, significance was lost after Bonferroni correction. HLA-DRB1^*11:01 had a significantly higher frequency in AD patients compared with NCs (12.4% vs. 1.8%, corrected P=0.048) and was regarded as a susceptibility factor associated with AD. DRB1^*08:03 was decreased in AD patients compared with NCs (10.8% vs. 19.3%, P=0.043). HLA-DRB1 functional group 'a', which includes DRB1^*15:01, seemed to be associated with the development of egg allergy in AD (P=0.033), but this result was not significant after Bonferroni correction.

Conclusions

HLA-DRB1 polymorphism is not associated with egg allergy, but HLA-DRB1^*11:01 is associated with AD in Korean children.

Human leucocyte antigen polymorphisms in nut-allergic patients in South Wales

BACKGROUND

Peanuts and tree nuts are among the most common foods provoking severe allergic reactions including fatal anaphylaxis. However, little is known of the underlying genetic and immunological mechanisms involved.

OBJECTIVE

Based on findings in other allergic diseases, we have investigated whether specific human leucocyte antigens (HLA) are associated with nut allergy.

METHOD

Eighty-four patients presenting at the allergy clinic with symptoms of nut allergy were typed for the HLA Class I (HLA-A and B) and Class II (HLA-DRB1 and DQB1) loci by PCR using sequence-specific primers. Carriage frequencies were compared with 82 atopic non-nut-allergic subjects and 1798 random blood donors.

RESULTS

The frequency of HLA-B(*)07 (28.57%) and DRB1(*)11 (15.48%) was increased in the nut-allergic patients compared to the atopic controls (12.20% and 3.66%, respectively) but not when compared to the blood donors (28.86% and 10.12%). DRB1(*)13 and DQB1(*)06 were both increased in frequency in the nut allergy patients over both the atopic and blood donor controls. However, none of these increased frequencies were significant when corrected for the number of comparisons undertaken.

CONCLUSION

At HLA '2-digit resolution' and with undifferentiated patients with nut allergy, there are no major disturbances in the frequency of HLA-A, B, DRB1 or DQB1 types. However, the difference in frequency of HLA-DRB1(*)11 between the nut allergy patients and the atopic controls merits further investigation as this may represent an important phenotypic relationship.

A Role for IL-10-Mediated HLA-DR7-Restricted T Cell-Dependent Events in Development of the Modified Th2 Response to Cat Allergen

Although high dose exposure to inhaled cat allergen (Fel d 1) can cause a form of tolerance (modified Th2 response), the T cell mechanism for this phenomenon has not been studied. T cell responses to Fel d 1 were characterized in both allergic (IgE(pos)) and modified Th2 (IgE(neg)IgG(pos)) responders as well as serum Ab-negative controls (IgE(neg)IgG(neg)). Fel d 1 stimulated high levels of IL-10 in PBMC cultures from all individuals, with evidence of Th2 and Th1 cytokine skewing in allergic and control subjects, respectively. Using overlapping peptides, epitopes at the N terminus of Fel d 1 chain 2 were shown to stimulate strong T cell proliferation and to preferentially induce IL-10 (peptide 2:1 (P2:1)) or IFN-gamma (P2:2) regardless of the allergic status of the donor. Injection of cat extract during conventional immunotherapy stimulated expansion of IL-10- and IFN-gamma-producing chain 2 epitope-specific T cells along with increased Fel d 1-specific serum IgG and IgG4 Ab. Six of 12 modified responders expressed the major HLA-DRB1 allele, *0701, and both P2:1 and P2:2 were predicted ligands for this allele. Cultures from DR7-positive modified responders produced the highest levels of IL-10 to P2:1 in addition to other major and minor epitopes within chains 1 and 2. In the presence of anti-IL-10 mAb, both T cell proliferation and IFN-gamma production were enhanced in a Fel d 1- and epitope-specific manner. We conclude that IL-10-producing T cells specific for chain 2 epitopes are relevant to tolerance induction, and that DR7-restricted recognition of these epitopes favors a modified Th2 response.