کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
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1907219 | 1046340 | 2008 | 9 صفحه PDF | دانلود رایگان |

Aging is associated with a decrease in naïve (TN) and central memory (TCM), and an accumulation of effector memory (TEM and TEMRA) T cell subsets. Previously, we have demonstrated an increased sensitivity of TN and TCM CD4+ and CD8+ T cells in aging to TNF-α-induced apoptosis. In this investigation, we examined whether similar differential sensitivity is applicable to CD95-mediated apoptosis. We show that TN and TCM CD4+ and CD8+ T cells from aged subjects are significantly more sensitive to CD95-mediated apoptosis. Increased apoptosis is associated with increased activation of caspase-8 and caspase-3. Both caspase-8 and caspase-3 inhibitors blocked CD95-mediated apoptosis and activation of caspase-8 and caspase-3 in TN and TCM CD4+ and CD8+ T cells. No significant difference was observed in apoptosis or in activation of caspase-8 and caspase-3 in TEM and TEMRA CD4+ and CD8+ T cells between young and aged subjects; both populations were relatively and comparably resistant to CD95-mediated apoptosis and caspase activation. No correlation was observed between the sensitivity/resistance of any of the subsets of CD4+ or CD8+T cells to CD95-mediated apoptosis and the expression of CD95. Our data suggest that increased CD95-mediated apoptosis of TN and TCM CD8+ and CD4+ T cells may play a role in their decline in human aging.
Journal: Experimental Gerontology - Volume 43, Issue 4, April 2008, Pages 266–274