Figure 4.

Immune cellular bases for aging-associated alterations in generation of IFN-γ by immune cells of healthy old subjects. Columns and bars depict mean ± sd results of studies of NK/NKT cells and T cells from 3 healthy (group I) old female or male subjects and 3 young healthy female or male control subjects, with harvesting of supernates on d 2 (open bars) and d 3 (cross-hatched bars). Stimuli were 1 μg/well of anti-human CD3 + anti-human CD28 antibodies or combinations of 1 μg/well of anti-human CD3 antibody, 50 ng/ml of IL-18, 5 ng/ml of IL-2 or IL-12, and 50 ng/ml of phorbol myristate acetate (PMA). Significance of increases above and decreases below the 100% level, where values for young and old subjects would be the same, was calculated by a Mann-Whitney nonparametric test. ⁺P < 0.05; *P < 0.01.