Human platelets were activated with E. coli for 30 min at 37°C, in a ratio 1:10 (platelet: bacteria). The CD62P expression induced by the strain O111 was significantly higher compared with non-stimulated platelets (*p = 0.03, n = 6), but lower than the response to TRAP (**p = 0.004, n = 5). Previous inhibition of platelet TLR4, reduced significantly the exposure of P-selectin induced by the bacteria (*p = 0.03, n = 6). TLR4 inhibition had no effect on P-selectin expression in TRAP-stimulated platelets (A). Platelets in PRP, stimulated with LPS (10μg/mL) did not show signs of activation (n = 5) (B). The data was analyzed by Wilcoxon signed rank test, two-tailed.