Gender specificity of altered human immune cytokine profiles in aging

TLDR

Cytokine production by T cells and monocytes was quantified in 50 individuals aged 65 years or older and in age‑matched younger controls matched for sex, race, and national origin. The study found that aging alters cytokine profiles in a gender‑specific manner, with old men showing reduced IFN‑γ and IL‑17 production but increased levels in disease states, while old women exhibited elevated IFN‑γ (primarily from CD8 T cells) and disease‑associated increases in TNF‑α and IL‑6, highlighting distinct immune aging trajectories by sex.

Abstract

Cytokine generation by T cells and monocytes was determined for 50 subjects aged 65 yr or older and concurrently studied young subjects individually matched to each old subject for sex, race, and national origin. Highly significant differences between cytokine levels of old and young subjects all were gender specific. For T cells stimulated with anti-CD3 plus anti-CD28 antibodies, mean ratios of IFN-gamma generation for healthy old to young subjects were 0.22 for men (P<0.001; n=15) and 3.35 for women (P<0.001; n=13), and those of IL-17 were 0.30 for men (P<0.001) and no difference for women. CD8 T cells were the source of high IFN-gamma in healthy old women. For old men with an inflammatory or immune disease (n=10), mean old to young ratios of T-cell-generated IFN-gamma and IL-17 increased with disease severity up to 5.78 and 2.97 (both P<0.01), respectively, without changes for old women with similar diseases (n=12). For differentiated LPS-stimulated monocytes, old to young ratios of TNF-alpha and IL-6 generation were high only in women with immune or inflammatory disease (2.38, P<0.05 and 1.62, P<0.01, respectively), whereas ratios of IFN-gamma-evoked IP-10 chemokine were low in all groups. Alterations in immune cytokine profiles with aging show significant gender specificity.