.....Cross-sectional studies have established hallmark age-associated differences between adaptive immune factors in young and old people, particularly a lower number and percentage of naïve T cells, especially CD8+ T cells, and accumulations of late-differentiated CD8+ T cells. The latter but not the former is strongly affected by infection with the persistent ß-herpesvirus HHV5 (cytomegalovirus, CMV). Only limited longitudinal studies have so far investigated whether these differences actually reflect age-associated changes at the individual level. The Swedish OCTO/NONA-Immune studies identified a set of immune parameters including infection with CMV which predicted survival in people over 85 at baseline. Moreover, the Leiden 85+ study showed that T cell-mediated pro-inflammatory specific for CMV antigens was enriched in very old survivors, suggesting the overarching necessity of maintaining effective immunosurveillance of this virus.
Here, the disparate impact of CMV on "immunosenescence" and survival in human populations under different condition is reviewed
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