Annals of the New York Academy of Sciences, Vol 587, Issue 1 59-69, Copyright © 1990 by New York Academy of Sciences
Micronutrient status and immune function in tuberculosis
D. N. McMurray, R. A. Bartow, C. L. Mintzer and E. Hernandez-Frontera
Department of Medical Microbiology and Immunology, College of Medicine, Texas A&M University, College Station 77843.
Both macro- and micronutrients have been shown to affect resistance to
tuberculosis, which is mediated by macrophages activated by T lymphocytes.
Others have demonstrated inhibition of mycobacterial replication in
macrophage cultures treated with vitamin D or retinoic acid. We examined
the influence of dietary zinc and vitamin D on resistance to tuberculosis.
Guinea pigs were fed diets containing varying levels of zinc or vitamin D,
and infected 6 weeks later by the respiratory route with virulent
Mycobacterium tuberculosis. Zinc-deficient guinea pigs had fewer
circulating T cells and reduced tuberculin (PPD) hypersensitivity. The
response of peritoneal exudate macrophages to the lymphokine MIF was
impaired. Zinc deprivation did not influence disease resistance in
BCG-vaccinated or nonvaccinated animals. Vitamin D deficiency adversely
affected the tuberculin reaction and ability to control the infection.
Lymphocytes from vitamin D-deprived animals did not proliferate normally
when cultured with PPD. A diet supplemented with vitamin D enhanced T cell
responses to PPD in vivo. These results suggest that zinc and vitamin D
status affect immunity to tuberculosis.
