EXPRESSION OF NEUTROPHIL AND MONOCYTE CD-11B CD-18 ADHESION MOLECULESAT DIFFERENT SITES OF THE CORONARY TREE IN UNSTABLE ANGINA-PECTORIS/

To assess the site of leukocyte activation in unstable angina, the exp ression of neutrophil and monocyte CD11B/CD18 adhesion molecules in 26 patients was measured from blood samples taken from the coronary osti um, the coronary sinus, and the coronary artery just distal to the cul prit lesion (postobstructive chamber), CD11B/CD18 adhesion molecules d etected by direct immunofluorescence evaluated by flow cytometry were significantly higher in the coronary sinus blood than in both the coro nary ostium and the postobstructive chamber blood, suggesting that leu kocyte activation takes place at the microcirculatory interface with t he injured myocardium, probably as the result of short but repeated ep isodes of myocardial ischemia.