HLA and bird breeder's hypersensitivity pneumonitis

Area of Science:

• Immunogenetics
• Pulmonary Medicine
• Allergy and Immunology

Background:

• Bird breeder's hypersensitivity pneumonitis (HP) is an immune-mediated lung disease.
• The role of Human Leukocyte Antigen (HLA) genes in HP susceptibility is not fully understood.
• Genetic factors are suspected to play a role in the development of HP.

Purpose of the Study:

• To investigate the association between HLA antigen status and bird breeder's HP.
• To identify specific HLA alleles or haplotypes linked to the disease.
• To explore the potential role of HLA-associated immune response (Ir) genes.

Main Methods:

• HLA antigen typing was performed on unrelated patients and related family members with bird breeder's HP.
• Comparison of HLA antigen frequencies between patients and healthy controls.
• Family studies to assess the segregation of HLA haplotypes with the disease.
• In vitro studies using HLA antisera to block lymphocyte responses to bird antigen.

Main Results:

• A statistically significant higher frequency of the HLABW40 antigen was observed in non-related patients (35%) compared to normal controls (10%).
• A consistent association of a specific HLA haplotype with bird breeder's HP was identified in three out of four studied families.
• Certain HLA antisera demonstrated the ability to block the blastogenic response to bird antigen, indicating an immune mechanism.

Conclusions:

• The findings strongly suggest a genetic predisposition to bird breeder's HP, linked to the HLA system.
• An HLA-associated immune response (Ir) gene likely contributes to the susceptibility or development of bird breeder's HP.
• Further research into HLA and immune response genes is warranted for understanding and potentially managing HP.