The effect of a mixture of alpha-tocopheryl phosphate plus di-alpha-tocopheryl phosphate (TPm) was studied in vitro on two cell lines, RASMC (from rat aortic smooth muscle) and human THP-1 monocytic leukemia cells. Inhibition of cell proliferation by TPm was shown in both lines and occurred with TPm at concentrations lower than those at which alpha-tocopherol was equally inhibitory. TPm led in nonstimulated THP-1 cells to inhibition of CD36 mRNA and protein expression, to inhibition of oxidized low-density lipoprotein surface binding and oxLDL uptake. In nonstimulated THP-1 cells, alpha-tocopherol had only very weak effects on these events.