Stable and unstable angina: Identifying novel markers on circulating leukocytes

There is currently no blood-based test that can rapidly and objectively distinguish between chest pain which is initiated by increased myocardial oxygen demand (stable angina pectoris (SAP)) and chest pain initiated due to decreased coronary blood flow (unstable angina pectoris (UAP)). Since leukocytes play an active role in the progression of coronary artery disease (CAD), we hypothesize these can provide novel markers of SAP and UAP. Here we use a microarray of 82 cluster of differentiation (CD) antibodies (plus controls) to selectively immobilize peripheral blood mononuclear cells. We find that the pattern of leukocyte immobilization from patients with CAD significantly differs from healthy donors. Within the CAD group, 15 SAP patients exhibited significant (p<0.05) changes in 8 of 82 CD antibody spots compared to 19 age-matched healthy blood donors. An additional ten CD antigens differed between healthy donors and patients with UAP (p<0.05). Furthermore, seven CD antibody spots are significantly different between SAP and UAP patients. These preliminary data suggest it is now appropriate to undertake a larger clinical trial to test the hypothesis that these antibody microarrays can monitor the progression from SAP to UAP.