Significance of interleukin 6 in patients with sarcoidosis.
Interleukin 6 (IL-6) levels in various materials from patients with sarcoidosis were determined. The subjects of the study were 38 patients with sarcoidosis and 28 healthy controls. For detection of IL-6, an enzyme-linked immunosorbent assay method was used. Interleukin 6 activity in serum was detected in 4 of 30 patients, but not in 19 controls. In bronchoalveolar lavage (BAL) fluid, following 20-fold concentration, IL-6 activity was detected in four of ten patients (nonsmokers) and three of seven controls (two of two smokers and one of five nonsmokers). Interleukin 6 levels in the supernatants of cultured monocytes and alveolar macrophages (AMs) were significantly higher (p < 0.01 and p < 0.01, respectively) in patients with sarcoidosis than in controls. Interleukin 6 production from monocytes tended to correlate with that from AMs. A significant correlation (r = 0.70, p < 0.05) was found between IL-6 production from AMs and the ratio of CD4+/CD8+ in BAL fluid, although no correlation was observed between that from monocytes and CD4+/CD8+ ratio in BAL fluid. Taken together, IL-6 may be involved in the initiation and maintenance of alveolitis by activating and causing the proliferation of T cells.
Second Department of Internal Medicine, Nagoya City, University Medical School, Japan.
K
K
Sahashi
Y
Y
Ina
K
K
Takada
T
T
Sato
M
M
Yamamoto
M
M
Morishita
D000328:Adult; D001992:Bronchoalveolar Lavage Fluid / Q000737:chemistry; D016516:CD4-CD8 Ratio; D002478:Cells, Cultured; D005260:Female; D006801:Humans; D015850:Interleukin-6 / Q000032:analysis*; D016676:Macrophages, Alveolar / Q000378:metabolism; D008297:Male; D008875:Middle Aged; D009000:Monocytes / Q000378:metabolism; D012507:Sarcoidosis / Q000276:immunology / Q000378:metabolism*; D014409:Tumor Necrosis Factor-alpha / Q000032:analysis
D015850:Interleukin-6; D014409:Tumor Necrosis Factor-alpha