TF and atherosclerosis: Similarly, platelet up-regulation of the expression of TF procoagulant activity in mononuclear cells was significantly impaired by pretreatment with the active metabolite of the antiplatelet drug clopidogrel.54 Noteworthy, in addition to TF induction, platelet-monocyte aggregates increase the expression of monocyte chemotactic protein-1 and interleukin 8, proinflammatory cytokines related to the progression of atherosclerosis.55–57