Specificity of the human innate immune response to isocyanate-albumin. PBMCs from non-isocyanate exposed individuals (N=4) were cultured with 500 µg/ml of control “mock exposed” albØ, HDI-albØ, heated/aggregated albØ, TMA-albØ, DNCB-albØ. The concentrations of MIF (open bars) and MCP-1 (filled bars) in the culture supernatants at 48 hours were measured by ELISA, and chitinase-1 enzyme activity (stripped bars) on day 5 was measured fluorometrically as described in the methods.