Replicative Senescence: Aging of Cells
Telomere: are extreme ends of chromosomes consisting of (TTAGGG)n repeats and are essential for chromosomal stability. Telomere are 5-15 kb long in human lymphocytes and approximately 50-100 bp/yr are lost in vivo
Telomere lengths is maintained by a highlyspecialized ribonucleoprotin called telomerase
Replicative Senescence on AIDS:In AIDS patients there is an increase in number of CD28-CD8+ cells shortening of telomeres in CD8 cells suggest extensive replicative history as a result of clonal expansions
(Effros et al AIDS 10F17, 1996)