Arterial stiffness is a well-known predictor of future cardiovascular events. However, the underlying mechanism of arterial stiffening is not well known. We investigated the relationship between arterial stiffness and T cell immunosenescence, which is linked to cytomegalovirus (CMV) infection.Design and Method:
Arterial stiffness was evaluated using pulse wave velocity (PWV) measurements in 415 Koreans (age 59 ± 12 years). We also investigated the frequency of CD57+ or CD28null senescent T cells in peripheral blood lymphocytes and analyzed which immune parameters were correlated with PWV. In addition, CMV-specific T cells were stimulated with overlapping peptides covering pp65 protein, and T cell function was evaluated by intracellular cytokine staining of IFN-γ and TNF-α. Cytotoxic function of T cells was also measured by CD107a staining.Results:
In a multivariate analysis, the frequency of CD57+ cells in the CD8+ T-cell subset was independently correlated with PWV. Because a major population within CD8+CD57+ T cells is known to be reactive to CMV, we analyzed CMV-specific immune responses. CMV pp65-specific T cells were more frequently observed in the CD8+CD57+ population than in the CD8+CD57- population. Multivariate analysis revealed that the frequency of CMV pp65-specific IFN-g+, TNF-a+, or CD107a+ cells in the CD8+ T-cell subset was independently correlated with PWV.Conclusions:
We demonstrate that arterial stiffness is associated with senescent CD57+ T cells and CMV pp65-specific T cells in the CD8+ T-cell subset. Our data suggest a possible role of CMV-specific, senescent CD8+CD57+ T cells in the pathogenesis of arterial stiffening.