Acute coronary syndromes are associated with a reduction of VLA-1+ peripheral blood T cells and their enrichment in coronary artery plaque aspirates

Memory T cells producing interferon (IFN)γ and expressing very late antigen-1 (VLA-1) integrin collagen receptors are found in carotid atherosclerotic plaques, suggesting their involvement in coronary artery disease (CAD) as well. To determine the role of VLA-1+ T cells in CAD percent of CD3+ T cells binding monoclonal antibodies (mAb) to VLA-1 in peripheral blood (PB), and in coronary plaque material aspirated during coronary arterography and arterial blood, were analyzed in a cohort of 117 patients with CAD and 34 controls without CAD. % VLA-1+ T cells in PB was 0.63 ± 0.09% in controls compared to 0.96 ± 0.95% in patients with CAD (p < 0.009). The increase was due to a marked elevation of % VLA-1+ T cells in stable CAD (1.6 ± 0.27%) whereas %VLA-1+ T cells during acute coronary syndromes (ACS) and in patients with ischemia by thalium SPECT scan had significantly lower levels. %VLA-1+ T cells in coronary artery plaque material aspirated during therapeutic angiography in patients with ACS was significantly higher than in arterial blood (1.39 ± 0.96% vs 0.75 ± 0.84%, p < 0.035, n = 3). Thus, % VLA-1+ T cells increases in the PB during stable CAD but decreases in ACS. The finding of their enrichment in coronary blood containing atherosclerotic plaque aspirates suggests that a shift of VLA-1+ T cells from blood to atherosclerotic plaques may play a role in plaque instability in patients with ACS.