The impact of Pan3CSK4 on the platelet activation and the expression of TLR2 on it
Objective To investgate role of TLR2 in the activation, the innate immune and inflammation of human platelets. Methods Human washed platelets were separated from healthy people(n=5) and were stimulated with different concentrations(1μg/ml, 5μg/ml, 10μg/ml) of TLR2 agonistPam3CSK4(a synthetic bacterial lipoproteins). Then the platelet aggregation rate, the expression of CD62p and TLR2 on the platelet surface were measured. Results The platelet aggregation rate were (28.32±5.67)%, (52.56±8.54)% and (76.24±11.23)%, respectively, at concentration of 1μg/ml, 5μg/mland 10μg/ml of Pam3CSK4, more than (12.83±2.43)% at 0μg/ml of it. In addition, the expression of CD62p were (18.45±2.66)%, (22.45±2.04)%, (29.53±4.08)%, respectively at above concentration of Pam3 CSK4, more than (11.20±1.67)% of CD62p at control group(P<0.01). The expression of TLR2 was not significantly increased at a lower concentration of Pam3CSK4(1μg/ml) with (16.85±6.10)% compared with(10.81±3.99)% at the control group. However, it were (21.15±9.90)% and (22.52±9.26)%, respectively, at a higher concentration(5μg/ml, 10μg/ml)more than(10.81±3.99)% at the control group(P<0.05). Conclusion Pam3CSK4 induce aggregation, activation and the up-regulation of TLR2 of platelet by stimulating TLR2 receptor of it. Thereafter, TLR2 play an important role in the innate immune of platelet. 
 
Key words: 
Platelet;  Toll-like receptor 2;  Platelet aggregation;  Platelet activation;  CD62p