Decreased Apoptosis and Tissue Factor Expression After Lipid Lowering

To the Editor: We have read with interest the article by Aikawa et al.1 The authors found a drastic decrease in tissue factor expression and tissue factor activity in rabbit atherosclerotic plaques after lipid lowering. This was associated with a strong decrease in the number of macrophages in the plaques. Aikawa et al proposed that this could be a consequence of decreased macrophage replication or induction of apoptosis. Interestingly, we found that apoptosis was not increased but decreased after lipid lowering in this model.2 Moreover the proapoptotic protein Bax, which is upregulated in both human3 and experimental atherosclerotic plaques, was strongly decreased after lipid lowering.2 Furthermore, we demonstrated that the changes in cell composition of the plaques could be …