Human T-cell function in experimental ascorbic acid deficiency and spontaneous scurvy

• Published in: The American journal of clinical nutrition Vol. 36; no. 1; pp. 127 - 130
• Main Authors: Kay, NE, Holloway, DE, Hutton, SW, Bone, ND, Duane, WC
• Format: Journal Article
• Language: English
• Published: United States Elsevier Inc 01-07-1982
• Subjects: Adult; Ascorbic Acid - blood; Ascorbic Acid Deficiency - immunology; cellular immunity; delayed hypersensitivity; helper cells; Humans; Leukocytes - analysis; Male; Middle Aged; Phytohemagglutinins - pharmacology; Receptors, Immunologic - analysis; Scurvy - immunology; suppressor cells; T-lymphocytes; T-Lymphocytes - analysis; T-Lymphocytes - physiology; suppressor cells; T-lymphocytes; helper cells; delayed hypersensitivity; cellular immunity
• ISSN: 0002-9165; 1938-3207
• DOI: 10.1093/ajcn/36.1.127

Studies in animal models suggest that ascorbic acid deficiency impairs T-cell-mediated immunity. We studied five normal volunteers hospitalized on a metabolic unit and consuming a strictly controlled diet deficient in ascorbic acid 1) after a 5-wk control period of ascorbic acid supplementation (75 mg/day) and 2) after a 9-wk period of no supplementation. Three of the subjects were restudied after a 5-wk period of ascorbic acid supplementation after the deficient period. At the end of both control periods ascorbic acid levels in plasma ranged from 0.9 to 1.3 mg/dl and in leukocytes from 19 to 30 µg/108 cells. At the end of the deficient period levels of ascorbic acid in plasma ranged from 0.09 to 0.15 mg/dl and in leukocytes from 6.2 to 10 µg/108 cells, levels at or below those frequently found in frank scurvy. None of the T-cell parameters tested including mitogen responsiveness to phytohemagglutinin and percentage of T-cells bearing receptors for IgM (helper cells) and IgG (suppressor cells) was different in the deficient period compared to the control periods. One patient with spontaneous scurvy (plasma ascorbic acid 0.07 mg/dl, leukocyte ascorbic acid 4.9 µg/108 cells) was studied at the time of admission and after vigorous ascorbic acid repletion. All T-cell parameters after repletion were unchanged from admission. We conclude that in man ascorbic acid deficiency, even at the scorbutic level, does not alter T-cell numbers or impair in vitro T-cell function.