Immunogenetic studies on HLA-DR in German coal miners with and without coal worker's pneumoconiosis.

Coal worker's pneumoconiosis is caused by the pulmonary deposition of coal dust, including silica particles. Several factors such as chemical composition and physical properties of silica-containing dust, particle size distribution, intensity, and duration of exposure influence the disease development. Genetic factors may also be involved. To define whether HLA-DRB may function as a genetic factor for predisposition to coal worker's pneumoconiosis, we determined DRB1, 3, 4, 5 alleles. For this purpose, DRB typing with sequence-specific oligonucleotide probes in 204 German miners with pneumoconiosis and in 52 German miners without pneumoconiosis was used. The miners had worked under comparable conditions. The frequency of DR8 (1*0801-0804) was increased in patients developing pneumoconiosis during the first 15 years of mining (p = 0.047). The frequency of DR1 (1*0101-0103) was elevated (p = 0.022) and that of DR52 (3*0101, 3*0201, 3*0202, and 3*0301) was reduced (p = 0.026) in miners without pneumoconiosis. Our data show that the presence of DR1 and the absence of DR52 support the resistance to coal worker's pneumoconiosis. Furthermore, DR8 may be involved in the rapid development of coal worker's pneumoconiosis.