Zinc and immune function: the biological basis of altered resistance to infection

• Published in: The American journal of clinical nutrition 1998-08, Vol.68 (2S), p.447S-463S
• Main Authors: Shankar, A.H, Prasad, A.S
• Format: Article
• Language: English
• Subjects: Animals; antioxidants; apoptosis; Apoptosis - drug effects; B-lymphocytes; Biological and medical sciences; biological resistance; cell biology; cell cycle; cell division; cytokines; Cytokines - physiology; dietary mineral supplements; dose response; fetal development; glucocorticoids; Glucocorticoids - physiology; horizontal resistance; Humans; immune response; Immune system; immunity; Immunity - drug effects; immunosuppression (physiological); infection; Infection - immunology; Infections; literature reviews; lymphocyte proliferation; macrophages; Medical sciences; Metabolic diseases; monocytes; natural killer cells; neutrophils; nutrient deficiencies; nutritional status; Other nutritional diseases (malnutrition, nutritional and vitamin deficiencies...); T-lymphocytes; Thymic Factor, Circulating - physiology; thymulin; thymus hormones; trace element deficiencies; Zinc; Zinc - deficiency; Zinc - pharmacology
• ISSN: 0002-9165; 1938-3207
• DOI: 10.1093/ajcn/68.2.447s

Zinc is known to play a central role in the immune system, and zinc-deficient persons experience increased susceptibility to a variety of pathogens. The immunologic mechanisms whereby zinc modulates increased susceptibility to infection have been studied for several decades. It is clear that zinc affects multiple aspects of the immune system, from the barrier of the skin to gene regulation within lymphocytes. Zinc is crucial for normal development and function of cells mediating nonspecific immunity such as neutrophils and natural killer cells. Zinc deficiency also affects development of acquired immunity by preventing both the outgrowth and certain functions of T lymphocytes such as activation, T(h)1 cytokine production, and B lymphocyte help. Likewise, B lymphocyte development and antibody production, particularly immunoglobulin G, is compromised. The macrophage, a pivotal cell in many immunologic functions, is adversely affected by zinc deficiency, which can dysregulate intracellular killing, cytokine production, and phagocytosis. The effects of zinc on these key immunologic mediators is rooted in the myriad roles for zinc in basic cellular functions such as DNA replication, RNA transcription, cell division, and cell activation. Apoptosis is potentiated by zinc deficiency. Zinc also functions as an antioxidant and can stabilize membranes. This review explores these aspects of zinc biology of the immune system and attempts to provide a biological basis for the altered host resistance to infections observed during zinc deficiency and supplementation.