To our knowledge, results of the present study represent the first to examine time-dependent changes in production of MV/ exchange of cell-specific antigens in cells derived from whole blood incubated with LPS. In diluted blood, addition of LPS (500 ng or 1 mg/mL) increased the number of MV from platelets and those positive for tissue factor but only after four hours of incubation [34] . Because the blood was diluted, unlike the present study, cell-cell interactions were most likely attenuated and no evaluation was performed relative to interaction with leukocytes which could have indirectly affected platelet activation and production of cytokines.