Cell-mediated immune response and cytokine production in idiopathic senile anorexia

Some aspects of humoral and cell-mediated immunity and the capacity of peripheral blood mononuclear cells (PBMCs) of fourteen elderly persons with idiopathic anorexia to produce several cytokines, such as tumor necrosis factor alpha (TNF alpha), interleukin-1 beta (IL-1 beta), interleukin-6 and interferon-gamma (IFN gamma), were studied and the results were compared with those obtained in a control group of ten age-matched, normal weight healthy subjects. In addition, spontaneous and induced production of these cytokines was also measured in cultures of PBMCs of fourteen healthy young individuals as a control group of age. A significant decrease in CD2 (pan T-cells) and CD4 (T-helper) lymphocyte subpopulations, but unchanged CD8 (T-suppressor) subset, and a reduced response in delayed cutaneous hypersensitivity tests were observed in senile underweight anorectic patients. Monocyte counts did not show significant differences between patients and control subjects. The spontaneous release by PBMCs of all the cytokines measured did not differ between the anorectic and either the elderly or young control group. A significant increase in IL-6 production after mitogen stimulation with tetradecanoylphorbol acetate (TPA) and phytohemagglutinin (PHA) after 24 and 48 h of culture, as well as a greater induced TNF alpha production after 48 h of incubation with the same mitogens, was found in the anorectic patients as compared with the elderly controls. However, stimulated production of both IL-1 beta with TPA and of IFN gamma with PHA did not differ significantly between anorectics and aged controls.(ABSTRACT TRUNCATED AT 250 WORDS)