Iron deficiency, but not underfeeding reduces the secretion of interferon-gamma by mitogen-activated murine spleen cells.
Interferon-gamma (IFN-γ), a cytokine primarily secreted by T and natural killer cells regulates cell-mediated and innate immunity. Iron deficiency, a public health problem in children impairs immune function. To determine whether reduced IFN-γ contributes to impaired immunity, we measured IFN-γ in supernatants of activated (2.5 μg/ml concanavalin A, 50 ng/ml anti-CD3 antibody) spleen cells from control (C), iron-deficient (ID), pair-fed (PF), and iron-replete mice for 3 (R3) and 14 days (R14) (11-12/group). Except for iron content, the low iron (5 ppm) and control (50 ppm) diets had identical composition. Mean indices of iron status after 51 days of feeding were as follows: C=PF≈R14>R3>ID (p<0.01). Iron deficiency, but not pairfeeding reduced IFN-γ concentration in mitogen-treated cells by 30-43% (p<0.05); iron repletion improved it. Reduced IFN-γ was not simply due to differences in IL-12 (IFN-γ inducer), percentage of CD3+ T cells, or impaired cell proliferation because these indices were not always decreased. It was likely due to a defect in T cell activation that leads to IFN-γ gene expression. IFN-γ positively correlated with indicators of iron status, body, and thymus weights (r=0.238-0.472; p<0.05). Reduced IFN-γ secretion during iron deficiency may affect response to infections.
Kuvibidila
Solo R
SR
Department of Nutritional Sciences, Oklahoma State University, Stillwater, OK 74078, USA. solokuv@msn.com
Gardner
Renee
R
Velez
M
M
Yu
L
L
D000818:Animals; D003677:Deficiency Diseases / Q000378:metabolism*; D005260:Female; D007371:Interferon-gamma / Q000378:metabolism*; D000090463:Iron Deficiencies; D051379:Mice; D008810:Mice, Inbred C57BL; D008934:Mitogens / Q000494:pharmacology*; D013154:Spleen / Q000166:cytology / Q000187:drug effects*
D008934:Mitogens; D007371:Interferon-gamma