FAP and atherosclerosis: 3.1. The FAP Expression in Human Coronaries Without and with Coronary Plaques with Different Levels of Atherosclerosis Progression Was Examined. FAP Staining Was Absent in Cross-Sections from Coronary Vessels with No Atherosclerosis, Whereas a Gradual Increase in Staining Was Observed with the Progression of Atherosclerotic Plaques