The effects of increasing weekly doses of ascorbate on certain cellular and humoral immune functions in normal volunteers.

Certain functions of the blood neutrophils and lymphocytes from normal adult volunteers were evaluated after the ingestion of increasing doses of ascorbate. Serum immunoglobulins and levels of C'3 and total hemolytic complement were also measured. Enhancement of neutrophil motility to a chemotactic stimulus of endotoxin-activated autologous serum was observed in normal adult volunteers after the ingestion of 2 and 3 g ascorbate daily. No alteration was observed at lower doses. Other neutrophil functions evaluated that remained unaltered by ascorbate, were postphagocytic hexose monophosphate shunt activity and myeloperoxidase mediated iodination of ingested protein. Stimulation of lymphocyte transformation to the mitogens phytohaemagglutinin and concanavalin A was detected after the daily ingestion of 1, 2, and 3 g of ascorbate. Mitogen-induced protein synthesis was unaffected. Serum levels of IgG, IgA, IgM, C'3, and C'4 and total complement activity were unaltered by ascorbate.