Beryllium (Be)-antigen stimulates tumor necrosis factor-alpha (TNF-alpha) from bronchoalveolar lavage (BAL) cells in chronic beryllium disease (CBD). This study tested the hypothesis that high concentrations of Be-stimulated TNF-alpha are related to polymorphisms in the TNF-alpha promoter and clinical markers of disease severity in CBD. Demographic and clinical information was obtained from patients with CBD (n = 20). TNF-alpha concentrations were measured in BAL cell culture supernatant by ELISA. A priori, we categorized CBD subjects as either high or low TNF-alpha producers using a cutoff of 1,500 pg/ml. The TNF-alpha promoter sequence, +64 to -1045, was determined by direct sequencing. Human leukocyte-associated antigen (HLA)-DPB1 and -DRB1 genotyping was determined by polymerase chain reaction (PCR). High Be-stimulated TNF-alpha was associated with TNF2 alleles, Hispanic ethnicity, presence of HLA-DPB1 Glu69, and absence of HLA-DR4. Be-stimulated TNF-alpha concentrations correlated with markers of disease severity, including chest radiograph, beryllium lymphocyte proliferation, and spirometry. We found no novel TNF-alpha promoter polymorphisms. These data suggest that the TNF2 A allele at -308 in the TNF-alpha promoter region is a functional polymorphism, associated with a high level of Be-antigen-stimulated TNF-alpha and that these high TNF-alpha levels indicate disease severity in CBD.

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Bronchoalveolar lavage (BAL) cells from patients with chronic beryllium disease (CBD) have been used to evaluate the beryllium-specific immune response and potential immunotherapeutics. Beryllium induces interferon‐γ (IFN‐γ), interleukin‐2 (IL‐2), tumour necrosis factor‐α (TNF‐α), interleukin‐6 (IL‐6) and interleukin‐10 (IL‐10) from BAL cells. An antibody to IL‐2 and recombinant human (rHu) IL‐10 is able to partially suppress the beryllium-stimulated immune response. To obtain BAL cells, bronchoscopy is required, providing risk to the patient and a limited number of cells to study the immune response. As a result, the objectives of the study were to determine 1) whether CBD peripheral blood mononuclear cells (PBMNs) stimulated with beryllium would produce a similar cytokine pattern as BAL cells, and 2) whether this response could be modulated by interleukin‐4 (IL‐4), an immunomodulatory cytokine.CBD and normal individuals' PBMN and BAL cells were stimulated with and without beryllium sulfate. To modulate this antigen-stimulated response, we added rHu IL‐4 to the unstimulated and beryllium-stimulated cells. IFN‐γ, IL‐2, TNF‐α, IL‐6 and IL‐10 cytokine concentrations were determined from cell supernatants by enzyme-linked immunosorbent assays (ELISA), while IL‐4 messenger ribonucleic acid (mRNA) was assessed using polymerase chain reaction (PCR).Beryllium did not stimulate any of these cytokines from normal PBMNs. Increasing levels of IL‐6 and TNF‐α were produced constituitively by CBD PBMNs over time. Compared to the unstimulated CBD PBMNs, beryllium stimulated significant IFN‐γ, TNF‐α, IL‐2, IL‐6 and IL‐10 production. This response was similar to that stimulated from CBD BAL cells, although of a much lower magnitude. Low levels of IL‐4 mRNA were found in CBD and control PBMNs, which were not increased with beryllium stimulation. The beryllium-stimulated cytokine levels were not decreased by the addition of IL‐4. IL‐4 was unable to downregulate any of these beryllium-stimulated cytokines from CBD BAL cells or increase IL‐4 mRNA from either CBD PBMN or BAL cells, and thus is an unlikely immunomodulatory agent in CBD.From the data, it was concluded that chronic beryllium disease peripheral blood mononuclear cells provide a model to study the beryllium-stimulated immune response. Interleukin‐4's inability to downregulate any of the beryllium-stimulated cytokines makes it an unlikely therapeutic candidate in chronic beryllium disease.