Background and objective: Human leukocyte antigen (HLA) class II gene products are involved in the antigen presentation of exogenous antigens. The aim of this study was to evaluate whether specific immunoglobulin (Ig)E responses to purified major allergens of Dermatophagoides pteronyssinus (Der p 1 and Der p 2) were associated with genotypes of HLA-DRB1 alleles.
Subjects and methods: Peripheral venous blood samples were collected from two groups of unrelated Korean adolescents: 168 subjects with positive skin response (wheal > or = 3 mm) to crude D. pteronyssinus allergens and 94 age-matched controls with negative skin response and low serum-specific IgE to crude D. pteronyssinus allergens. The former group was found to contain 104 with high serum-specific IgE to crude D. pteronyssinus allergens, 100 with high serum-specific IgE to Der p 1, and 122 with high serum-specific IgE to Der p 2. Genotypes of the HLA-DRB1 alleles were determined using polymerase chain reaction-sequence specific oligonucleotide probes.
Results: HLA-DRB1*07 was significantly higher in subjects with a high serum-specific IgE response to crude D. pteronyssinus allergens than the controls (16.3% vs 3.2%, odds ratio [OR] = 5.93, corrected P [Pc] = 0.02). The excess of DRB1*07 was more marked in those with high serum-specific IgE responses to Der p 1 or Der p 2 than the controls (20.0% vs 3.2%, OR = 7.58, Pc = 0.004; 18.9% vs 3.2%, OR = 7.05, Pc = 0.006). Among subjects with high serum IgE to Der p 1, DRB1*13 significantly increased than the controls (32.0% vs 13.8%, OR = 2.93, Pc = 0.03).
Conclusions: We clearly observed the association between HLA-DRB1 alleles and specific IgE responsiveness to D. pteronyssinus major allergens. The molecular mechanism of HLA-DRB1*07 and DRB1*13 involvement in D. pteronyssinus-specific IgE responsiveness awaits further investigation.