The effect of MD-2 blockade on lipopolysaccharide- (LPS) or interferon-γ (IFNγ) -stimulated matrix metalloproteinase 1 (MMP-1) secretion. (a, b) U937 cells cultured in normal (a) or high glucose (b)-containing medium were treated with 100 ng/ml of LPS in the absence or presence of different concentrations (2·5–10 μg/ml) of anti-MD-2 antibodies or 10 μg/ml of control antibodies for 24 hr. After the treatment, MMP-1 in culture medium was quantified using ELISA. (c, d) U937 cells cultured in normal (c) or high glucose (d) -containing medium were treated with 100 units/ml of IFN-γ in the absence or presence of different concentrations (2·5–10 μg/ml) of anti-MD-2 antibodies or 10 μg/ml of control antibodies for 24 hr. After the treatment, MMP-1 secretion was quantified using ELISA. (e) Human monocytes were treated similarly as U937 cells with IFN-γ as described above in the absence or presence of 5 μg/ml of anti-MD-2 antibodies or control antibodies. After the treatment, MMP-1 secretion was quantified using ELISA.