Does in vitro replicative senescence of human CD8+ cells reflect the phenotypic changes observed during in vivo ageing?

Immunosenescence is viewed as a remodeling process with the exhaustion of naïve T cells and filling up of the immunological space with memory cells. In this study some phenotypic changes of CD8(+) human cells during in vivo ageing were compared with those observed in long term cultures of lymphocytes derived from cord blood or from peripheral blood from donors of different age. Both in vivo and in vitro a significant decrease of the fraction of CD8(+)CD28(+) cells was observed. Comparing the proportions of other T cell subpopulations (the CD4/CD8(+) ratio, CD56, CD57, CD27) made it possible to conclude that replicative senescence in vitro partially reflects in vivo ageing.