OBJECTIVE: To test the hypothesis that the expanded population of non-proliferative CD28-
CD8+ T cells in HIV disease have shortened telomeres, thereby providing evidence that
increased rounds of CD8+ cell division occur during HIV disease, possibly leading to …

Telomerase reverse transcribes telomere DNA onto the ends of linear chromosomes and
retards cellular aging. In contrast to most normal somatic cells, which show little or no
telomerase activity, immune cells up-regulate telomerase in concert with activation …

A large proportion of the CD8+ T cell pool in persons chronically infected with HIV consists
of cells that show features of replicative senescence, an end stage characterized by
irreversible cell cycle arrest, multiple genetic and functional changes, and shortened …

Accelerated telomere shortening in lymphocytes has been associated with a variety of
human pathologies, including HIV disease, Down syndrome, and cardiovascular disease.
Recent findings indicate that reduced telomere length is also associated with chronic …

Induction of telomerase, the enzyme that extends telomeres, accompanies human T
lymphocyte activation. Nevertheless, high proportions of memory T cells with shortened
telomeres are present in vivo during HIV infection and aging. To elucidate the long-term …

Telomeres, the repeated sequences that cap chromosome ends, undergo shortening with
each cell division, and therefore serve as markers of a cell's replicative history. In vivo, clonal
expansion of T cells during immune responses to both foreign and autoantigens is …

Highly active antiretroviral treatment has resulted in dramatically increased life expectancy
among patients with HIV infection who are now aging while receiving treatment and are at
risk of developing chronic diseases associated with advanced age. Similarities between …

HIV risk behaviors, susceptibility to HIV acquisition, progression of disease after infection,
and response to anti-retroviral therapy all vary by age. In those living with HIV, current
effective treatment has increased the median life expectancy to> 70 years of age. Biologic …

The strict limit in proliferative potential of normal human somatic cells–a process known as
replicative senescence–is highly relevant to the immune system, because clonal expansion
is fundamental to adaptive immunity. CD8+ T cells that undergo extensive rounds of antigen …

Cells of the immune system are unique among normal somatic cells in that they have the
capacity to upregulate the telomere-extending enzyme, telomerase, albeit in a precisely
controlled fashion. Kinetic analysis of telomerase activity in long-term T cell cultures has …