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Immunologic modulation by vitamin C in the elderly.

J C Delafuente·J M Prendergast·A Modigh
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Abstract

Aging is associated with a decline in both humoral-mediated and cellular-mediated immunity. These aberrations may contribute to morbidity and mortality in the elderly. Since we have previously shown that vitamin C enhances in vitro and in vivo immune functions in young healthy volunteers, we studied the effects of vitamin C on certain immunologic parameters in an elderly population. In vitro lymphocyte proliferation to the mitogen concanavalin-A was significantly less when compared to a young control group. When lymphocytes from the elderly were pre-incubated overnight and cultured in the presence of 10 micrograms/ml of vitamin C, mitogen-stimulated lymphocyte proliferation was similar to that from controls without vitamin C in culture. Having demonstrated significant in vitro immunoenhancement with vitamin C, we next studied the effects of oral ingestion of 2 g of vitamin C daily on certain in vitro and in vivo immunologic parameters in the elderly. When compared with a placebo-treated group, 3 weeks of vitamin C treatment did not effect in vitro mitogen-stimulated lymphocyte proliferation or in vivo reactivity to common skin test antigens. The augmenting effects of in vitro vitamin C suggest that this essential vitamin may be an effective agent in modulating aberrant immunologic functions in the elderly. The clinical significance of these findings requires further study.

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AgedAgingAntigensAscorbic AcidConcanavalin AHumansImmune SystemIn Vitro TechniquesLymphocyte ActivationClinical TrialControlled Clinical TrialJournal ArticleResearch Support, Non-U.S. Gov't

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J C Delafuente, J M Prendergast, A Modigh. 1986. Immunologic modulation by vitamin C in the elderly.. https://doi.org/10.1016/0192-0561(86)90060-3

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