Adherent cells and lymphocytes were isolated from whole blood of healthy humans (controls, n = 4) and critically ill patients (n = 4). Adherent cells were incubated either with LPS (1 ng/mL) or SAC (0.075% wt/vol) in the presence or absence of rhIFN-γ (10 ng/mL) for 24 hours (A, B). In addition, lymphocytes from both experimental groups were incubated with LPS (1 ng/mL) or SAC (0.075% wt/vol) in the presence or absence of rhIL-12 p70 (5 ng/mL) for 24 hours (C). Concentrations of IL-12 p40 and p70 in adherent cell supernatants and of IFN-γ in lymphocyte supernatants were determined with specific ELISA. Data are presented as mean ± SEM; *P < .05 LPS/SAC versus LPS/SAC + rhIFN-γ/rhIL-12 p70; #P < .05 patient versus control.