Effect of platelet-derived LIGHT on chemokine-release from HUVECs and monocytes. The diagrams show the ability of a neutralizing antibody against LIGHT (anti-LIGHT; 100 μg/mL) to attenuate the effect of platelet releasate (PR) prepared from thrombin-stimulated platelets (0.1 U/mL; for 10 and 90 minutes) on the enhancement of MCP-1 (A) and IL-8 (B) from HUVECs after 5 hours of stimulation and MCP-1 (E) and IL-8 (F) from monocytes after 20 hours of stimulation. A control antibody of the same isotype (IgG) and concentration was used as a control. Data are presented as mean ± SEM, n = 6. *P < .05 versus HUVECs or monocytes stimulated with platelet releasate. (C-D) Effect of rhLIGHT (1-100 ng/mL) on protein levels of MCP-1 (C) and IL-8 (D) in monocyte supernatants stimulated for 20 hours. Data are presented as mean ± SEM, n = 6. *P < .05 and **P < .01 versus unstimulated cells.