Skewed representation of functionally distinct populations of Vgamma9Vdelta2 T lymphocytes in aging.
Exp Gerontol
; 40(1-2): 59-66, 2005.
Article
em En
| MEDLINE
| ID: mdl-15664733
ABSTRACT
We recently demonstrated that numerical and functional alterations of gammadelta T cells are present in healthy elderly. Here we observed that the decreased absolute number of Vgamma9Vdelta2 T cells present in old subjects in comparison with young/adult and middle aged donors is due to the reduction of naive and central memory Vgamma9Vdelta2 T cells bearing CD27 and CCR7 antigens. The proportion of effector/memory Vgamma9Vdelta2 T cells lacking CD27 or CCR7 markers was significantly increased in the peripheral blood of old subjects in comparison with younger donors. Moreover, the percentage of CD69+ gammadelta T cells was significantly increased in old subjects in comparison with younger donors after overnight activation, confirming that more effector cells are available in aged people. A functional analysis in young/adult and middle aged donors revealed that effector/memory CD27- Vgamma9Vdelta2 T cells are increased after 10-days of in vitro colture in the presence of isopentenylpyrophosphate (IPP) and IL-2. In contrast, the IPP+IL-2 mediated differentiation and expansion of CD27- effector/memory cells was absent in old subjects, confirming a lack of naive and central memory cells responding to IL-2. Accordingly, the expansion index of effector/memory CD27- Vgamma9Vdelta2 T cells was negatively correlated with the donor age. Finally, terminally differentiated Vgamma9Vdelta2 T cells measured as perforin content after 10-day in vitro expansion showed no age-related difference. These data demonstrated a shift of the circulating gammadelta T cell population towards CD27- and CCR7- effector T cells in the elderly with the reduction of immature CD27+ and CCR7+ T cell precursors.
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Base de dados:
MEDLINE
Assunto principal:
Envelhecimento
/
Subpopulações de Linfócitos T
/
Receptores de Antígenos de Linfócitos T gama-delta
Limite:
Adult
/
Aged
/
Aged80
/
Humans
/
Middle aged
Idioma:
En
Ano de publicação:
2005
Tipo de documento:
Article