AIM: To investigate whether increased plasma L-homocysteine (Hcy) level could promote monocyte chemoattractant protein-1 (MCP-1) and interleukin-8 (IL-8) in cultured whole blood. METHODS: Human whole blood or different type of peripheral blood cells from health volunteers were incubated with Hcy and/or the inhibitors. MCP- 1 and IL-8 level were measured by ELISA assay. RESULTS: Hcy 10-1000 μmol/L induced production of MCP-1 and IL-8 in cultured human whole blood (P＜0.05). The major cellular source of these chemokines comed from monocytes.Meanwhile,Hcy also promoted the upregulation of MPO level even at the 10 μmol/L in the cultured whole blood.secretion in cultured human whole blood, especially in monocytes via oxidative stress mechanism.