Fig 1.

Asbestos and silica activate IL-1β secretion in human macrophages. (A) THP1 cells were stimulated for 6 h with the indicated amounts (mg/ml media) of asbestos, silica, diesel exhaust particles (DEP), cigarette smoke extract (CSE, in % solution) and MSU. (B) THP1 cells were stimulated with 0.2 mg/ml asbestos, 0.5 mg/ml DEP and 0.2 mg/ml MSU for the indicated times. Media supernatants (SN) were analysed for the presence of mature IL-1β, and cell extracts (Cell) for the presence of proIL-1β by Western blotting. (C) LPS-primed primary human monocyte-derived macrophages (M-CSF) were stimulated for 6 h with asbestos (0.2, 0.1, 0.05 mg/ml), silica (0.5, 0.2, 0.1 mg/ml), DEP (0.2 mg/ml) and MSU (0.2 mg/ml) and analysed by ELISA for IL-1β released into the media. Values are means ± S.E.M.