Figure 2

Pxn-KD in platelets increases agonist-induced integrin αIIbβ3 activation. Bone marrow cells transduced with LentiLox-sh-control-GPIbα (Control) or LentiLox-sh-paxillin-GPIbα (Pxn-KD) at an MOI of 5 were transplanted into lethally irradiated recipient mice. (A) Activation of integrin αIIbβ3 was assessed by JON/A binding to platelets incubated with or without 1 mmol/L AYPGKF or 50 ng/mL convulxin. The plots represent the degree of GFP expression (horizontal) and binding of JON/A, a monoclonal antibody that recognizes activated integrin αIIbβ3 (vertical). (B) Columns and error bars represent the mean ± s.d. of the MFI of JON/A binding after stimulating GFP-positive platelets with the indicated agonists (n = 3–5). (C) Platelet aggregation induced by the indicated concentration of AYPGKF or convulxin was monitored by light transmission aggregometry. (D) Columns and error bars represent the mean ± s.d. of maximal platelet aggregation after stimulation (n = 5). Open bars: control platelets; black bars: Pxn-KD platelets. Statistical significance was determined by the Student’s t-test. *P < 0.05, **P < 0.01, and ***P < 0.001.