Rationale: There is mounting evidence of a higher incidence of coronary heart disease in cytomegalovirus-seropositive individuals.
Objective: The aim of this study was to investigate whether acute myocardial infarction triggers an inflammatory T-cell response that might lead to accelerated immunosenescence in cytomegalovirus-seropositive patients.
Methods and results: Thirty-four patients with acute myocardial infarction undergoing primary percutaneous coronary intervention were longitudinally studied within 3 months after reperfusion (Cohort A). In addition, 54 patients with acute myocardial infarction and chronic myocardial infarction were analyzed in a cross-sectional study (Cohort B). Cytomegalovirus-seropositive patients demonstrated a greater fall in the concentration of terminally differentiated CD8 effector memory T cells (TEMRA) in peripheral blood during the first 30 minutes of reperfusion compared with cytomegalovirus-seronegative patients (-192 versus -63 cells/μL; P=0.008), correlating with the expression of programmed cell death-1 before primary percutaneous coronary intervention (r=0.8; P=0.0002). A significant proportion of TEMRA cells remained depleted for ≥3 months in cytomegalovirus-seropositive patients. Using high-throughput 13-parameter flow cytometry and human leukocyte antigen class I cytomegalovirus-specific dextramers, we confirmed an acute and persistent depletion of terminally differentiated TEMRA and cytomegalovirus-specific CD8(+) cells in cytomegalovirus-seropositive patients. Long-term reconstitution of the TEMRA pool in chronic cytomegalovirus-seropositive postmyocardial infarction patients was associated with signs of terminal differentiation including an increase in killer cell lectin-like receptor subfamily G member 1 and shorter telomere length in CD8(+) T cells (2225 versus 3397 bp; P<0.001).
Conclusions: Myocardial ischemia and reperfusion in cytomegalovirus-seropositive patients undergoing primary percutaneous coronary intervention leads to acute loss of antigen-specific, terminally differentiated CD8 T cells, possibly through programmed cell death-1-dependent programmed cell death. Our results suggest that acute myocardial infarction and reperfusion accelerate immunosenescence in cytomegalovirus-seropositive patients.
Keywords: aging; cytotoxic T-lymphocytes; human cytomegalovirus; myocardial infarction; programmed cell death 1; reperfusion; telomere.
© 2014 The Authors. Published on behalf of the American Heart Association, Inc., by Wolters Kluwer.