Prolonged tomato juice consumption has no effect on cell-mediated immunityof well-nourished elderly men and women

The immunomodulatory potential of carotenoids has been investigated thoroug hly only for beta-carotene, Data on the immunomodulatory activity of other carotenoids such as lycopene are scarce. The objective of this study was to investigate the effects of prolonged tomato juice consumption on cell-medi ated immunity of well-nourished healthy elderly persons. In an intervention study, 33 female and 20 male subjects (aged 63-86 y) consumed 330 mL/d tom ato juice (47.1 mg/d lycopene) or mineral water for 8 wk. Immune status was assessed by measuring number and lytic activity of natural killer (NK) cel ls, secretion of cytokines [interleukin (IL)-2, IL-4, tumor necrosis factor -alpha (TNF-alpha)] by activated peripheral blood mononuclear cells (PBMC), lymphocyte proliferation, and delayed-type hypersensitivity (DTH) skin res ponses. Tomato juice consumption resulted in significantly increased plasma lycopene and beta-carotene concentrations over time. In both treatment gro ups, TNF-or and IL-4 secretion were increased at the end of the interventio n period, whereas IL-2 secretion was decreased. Tomato juice consumption ha d no effect on lymphocyte proliferation, DTH or the number of NK cells. Lyt ic activity of NK cells was increased in both groups at the end of the inte rvention period. In conclusion, these results show that prolonged tomato ju ice consumption increased plasma lycopene concentrations without significan tly affecting cell-mediated immunity in well-nourished elderly subjects.