Aggregation of wild-type, Tec^-/-, Btk^-/-, and Btk^-/-/Tec^-/-murine platelets in response to CRP and ADP. Traces showing the effect of loss of Tec, Btk, or both on platelet aggregation responses to (A) ADP and CRP, (B) collagen and, (C) CRP with ADP. Aggregation was conducted using platelets at a concentration of 1.5 × 10⁸/mL in diluted heparinized platelet-rich plasma (PRP). Agonist addition was timed at 30 seconds, and subsequent monitoring using a Chronolog 490-2D aggregometer (ChronoLog) was maintained for 5 minutes. The scale indicates the percentage change in optical density where resting PRP (diluted) is set at 0% and platelet-poor plasma is equivalent to 100%. Traces are illustrative of at least 4 separate experiments.