Effect of various cytokines on production of IL-8 from monocytes and endothelial cells. Monocytes (1 × 10⁶cells/mL) and human umbilical venous cells (VE cells, confluent) were cultured with or without LPS (500 ng/mL), IL-1 (10 U/mL), TNF- (10 ng/mL), IFN-γ (200 U/mL), and M-CSF (100 ng/mL) in 24-well plates. After 2 days, supernatants were collected and an ELISA system for IL-8 was performed. Columns represent the mean ± SD (bar) of three independent experiments. Statistical analysis was performed using the Student’s t-test. *P < .01.