FIG. 1.
Induction of release of proinflammatory cytokines from MM6-CA8 cells by various pyrogens. The cells were primed with 10 ng of calcitriol/ml. After incubation for 72 h at 37°C with calcitriol, the cells were plated in a 24-well plate at 106 cells/0.9 ml/well, and 0.1 ml of pyrogen at various concentrations was added to each well. After incubation for 17 h at 37°C, the release of IL-6, TNF-α, or IL-1 in culture supernatants was evaluated by an ELISA. The amounts of cytokines released from MM6-CA8 cells cultured in a medium containing 0 μg of pyrogen/ml were as follows: IL-6, 2.1 ± 0.7 pg/ml; TNF-α, 0.6 ± 0.3 pg/ml; and IL-1, 2.5 ± 0.6 pg/ml. Data are expressed as the mean and SEM (n = 6 to 12).