T-lymphocyte subsets and interleukin-2 production in zinc-deficient rats.
1. It has been suggested that zinc-deficiency impairs cellular (T-lymphocyte-mediated) immune responses via a selective effect on helper T-lymphocytes. We have addressed this question in the rat by employing recently developed reagents in the form of monoclonal antibodies which specifically identify rat T-lymphocyte subsets (identifying total T-cells, helper T-cells and suppressor T-cells) and also by quantifying helper T-cell function by measurement of the helper T-cell-derived molecule interleukin-2 (IL-2). 2. Zn-deficiency induced T-cell atrophy (assessed morphologically and phenotypically with anti-rat T-cell monoclonal antibodies) in both peripheral blood and spleen. The use of these specific monoclonal antibodies failed to demonstrate a selective effect of Zn deficiency on the helper T-cell fraction of the total T-lymphocyte population. 3. In contrast, the results of functional assays of the T-lymphocyte response were dependent on the conditions of culture but suggested that the generation of IL-2 and its corresponding receptor were determined by the intracellular Zn status. Thus, in vivo, helper T-lymphocyte numbers are non-specifically reduced since other T-cell subsets are also reduced in response to appropriate stimulation. The functional consequences of this are dependent on the intracellular concentration of Zn but appear to influence both IL-2 production and its receptors on activated T-cells.
D000818:Animals; D000911:Antibodies, Monoclonal / Q000032:analysis; D002478:Cells, Cultured; D007111:Immunity, Cellular; D007376:Interleukin-2 / Q000096:biosynthesis*; D008213:Lymphocyte Activation; D051381:Rats; D011919:Rats, Inbred Strains; D013154:Spleen / Q000276:immunology; D013601:T-Lymphocytes / Q000145:classification / Q000276:immunology*; D006377:T-Lymphocytes, Helper-Inducer / Q000276:immunology; D015032:Zinc / Q000172:deficiency*
D000911:Antibodies, Monoclonal; D007376:Interleukin-2; D015032:Zinc