Biology and Pharmacology of Novel Targets for Antiplatelet Therapy

wellasthevehicle(PBS),wereaddedtohumanarterialECsandECapoptosis,number,size,capacityfor in vitro-reendothelialisation after scratching, expression of adhesion molecules ICAM-1 and VCAM-1 were assessed. In parallel, platelet-, endothelial- and leukocyte-derived MPs were quantified. In a sep- arate sub-study, the same parameters were assessed in plasma of CAD patients undergoing standard medical rehabilitation or an exercise-based cardiac rehabilitation programme. Results: MPs of healthy, but not of CAD patients supported in vitro re-endothelialisation, while exo- somes had no influence. Exercise, but not standard rehabilitation improved CAD MP capacity to support in vitro rehabilitation. This was negatively correlated to the number of leukocyte- and endothelial-derivedMPs,butnottotalorplateletMPs.ECnumberwasnegativelyaffectedbyexposure to CAD MPs. ANCOVA analysis identified disease, but not the particle type as influencing factor. Instead, apoptotic cell death was influenced by particle type, but not by the disease, and was not alteredin rehabilitation.Similarly, ICAM-1and VCAM-1 expressionwereenhanced onECsafterincu- bation with exosomes, but not with MPs, with no effect of disease or rehabilitation. Conclusion: MPs and exosomes differentially affect endothelial cell function and underlie differential modulation in disease and rehabilitation. Those findings might in the future help to optimize and monitor cardiovascular therapy.