Enhanced aggregation and granular secretion following GPVI stimulation in ELMO1^−/−platelets. Representative aggregation (A) and dense granule secretion tracings (B) of washed platelets from ELMO1^−/− or WT littermate controls activated with the indicated agonists for 4 minutes. Platelet aggregation and dense granule secretion was detected by lumiaggregometry under stirring conditions at 37°C. Quantification of extent of aggregation (C) and dense granule secretion (D) of at least 3 independent experiments from panels A and B, respectively. Data are presented as mean ± SE and were analyzed by Student t test (*P < .05). Flow cytometry analysis of P-selectin exposure (E) and activated integrin αIIbβ3 (F) of washed murine platelets from ELMO1^−/− or WT littermate controls activated with the indicated concentrations of CRP for 10 minutes at 37°C. Data are presented as fold increase over basal ± SE from at least 3 independent experiments and were analyzed by Student t test (*P < .05). A.U, arbitrary units.