Histone-induced CXCL10 production is dependent on TLR4 and IFN-γ.

(A) CTHs (60 μg/ml) were added to heparinized blood in presence of antibodies against human TLR2 (25 μg/ml), human TLR4 (25 μg/ml) or isotype control (25 μg/ml). After a 12-hour incubation at 37°C, the release of CXCL10 was measured. Blood stimulated with CTHs in the absence of an antibody served as control. (B) CTHs (60 μg/ml) were mixed with heparinized blood in the presence or absence of the TLR4 antagonist CLI-095 (1.25 μg/ml). After a 12-hour incubation at 37°C, the release of CXCL10 was measured. Blood stimulated with CTHs in the absence of antagonist served as control. (C) CTHs (60 μg/ml) were incubated with heparinized blood in presence of antibodies against human IFN-γ (25 μg/ml) or an isotype control (25 μg/ml). After a 12-hour incubation at 37°C, the release of CXCL10 was measured. Blood stimulated with CTHs in the absence of an antibody served as control.