Zinc induces thymulin secretion from human thymic epithelial cells In vitro and augments splenocyte and thymocyte responses In vivo

• Published in: International journal of immunopharmacology Vol. 17; no. 9; pp. 729 - 733
• Main Authors: Saha, Anutosh R., Hadden, Elba M., Hadden, John W.
• Format: Journal Article
• Language: English
• Published: England Elsevier Science 01-09-1995
• Subjects: Administration, Oral; aging; Aging - immunology; Cells, Cultured; Epithelial Cells; Humans; immune restoration; Immunotherapy; interleukins; mitogens; Receptors, Interleukin-2 - metabolism; Spleen - cytology; Spleen - drug effects; stress; thymic epithelial cells; Thymic Factor, Circulating - drug effects; Thymic Factor, Circulating - metabolism; thymic involution; thymulin; thymus; Thymus Gland - cytology; Thymus Gland - drug effects; Thymus Gland - metabolism; zinc; Zinc - administration & dosage; Zinc - pharmacology; stress; thymus; thymic involution; thymic epithelial cells; thymulin; mitogens; aging; zinc; immune restoration; interleukins
• ISSN: 0192-0561; 1879-3495
• DOI: 10.1016/0192-0561(95)00061-6

Zinc is incorporated into zinc-thymulin by the thymus and in this form is a critical hormonal regulator of cellular immunity. In the absence of serum, zinc induces human thymic epithelial cells (TEC) to secrete a factor which promotes the expansion of interleukin-2 (IL-2) receptor positive human peripheral blood lymphocytes in response to a low dose of phytohemagglutinin (PHA). This factor is removed by antithymulin antisera plus filtration and is thus presumed to be zinc-thymulin. Intraperitoneal treatment of hydrocortisone treated aged mice with zinc-thymulin (100 ng/day ×5) resulted in mild augmentation of splenocyte but not thymocyte responses
in vitro to IL-1, IL-2, and natural cytokine mixture (NCM) and to PHA and concanavalin A (Con A) (average increase 40%). Like zinc-thymulin treatment, oral ingestion of zinc (72 μg/day × 5) resulted in augmentation of splenocyte IL responses; in contrast, it augmented thymocyte responses to all stimuli (average increase 100%). These preliminary experiments indicate that treatment with zinc may have immunotherapeutic relevance, particularly in the aged and stressed organism.