A number of model systems have been employed to investigate age-associated changes in immune function. The purpose of the current study was to characterize senescent T cells and to investigate the inflamm-aging phenomenon both in vitro and in vivo using the old horse as a model. We examined whether decreased T cell proliferation induced by Con A is caused by increased apoptosis. We also utilized intracellular CFSE to analyze changes within each round of cell proliferation, in particular cytokine production. Intracellular staining with flow cytometry, RT-PCR, and ELISA were used to measure pro-inflammatory cytokines both in vitro and in vivo. While lymphocytes from old horses exhibit decreased proliferation, this is not the result of increased apoptosis. Instead, a larger percentage of the T cells remain in the parent generation and produce significant amounts of IFNγ. Likewise, old horses have increased frequency of CD8-IFNγ+ T cells and TNFα producing cells. We also show that old horses have elevated levels of IL-1β, IL-15, IL-18 and TNFα gene expression in peripheral blood and significant levels of TNFα protein in serum, all characteristics of inflamm-aging.
|Number of pages||9|
|Journal||Mechanisms of Ageing and Development|
|State||Published - Nov 2008|
Bibliographical noteFunding Information:
This work was supported by the William Robert Mills endowment and the Jeffrey C. Hughes Foundation, Gluck Equine Research Center. Lynn Ennis and the staff at the University of Kentucky’s Maine Chance Farm are recognized for their care of the horses.
- Inflammatory cytokines
ASJC Scopus subject areas
- Developmental Biology