A Comprehensive Analysis of Cytokine Network in Centenarians

Cytokines have been investigated extensively in elderly people, with conflicting results. We performed a comprehensive analysis of the plasma levels of 62 cytokines and growth factors involved in the regulation of the immune system, in healthy centenarians, and middle-aged controls. We confirmed the previously observed increase in the levels of several pro-inflammatory cytokines, such as TNF-alpha and IL-6, and found that several other cytokines, directly or indirectly involved in inflammation (such as IFN-alpha, IL-23, CCL-5), were present at higher levels in centenarians. We did not observe any increase in the levels of anti-inflammatory cytokines, with the notable exception of the Th2-shifting cytokine IL-19. No relevant difference was observed in cytokines regulating T cell immunity. Several growth factors having a role in regulating immunity, such as G-CSF, GM-CSF, EGF, and VEGF, were upregulated in centenarians, too. Principal component analysis of the cytokine dataset showed that pro and anti-inflammatory cytokines were the variables that contributed the most to the variability of the data we observed.

Automated summary

In this study, we analyzed the levels of 62 cytokines and growth factors in healthy centenarians and middle-aged controls. We found an increase in pro-inflammatory cytokines in centenarians, as well as other cytokines involved in inflammation. Anti-inflammatory cytokines did not show an increase, except for the Th2-shifting cytokine IL-19. Several growth factors involved in regulating immunity were also upregulated in centenarians. Principal component analysis showed that pro and anti-inflammatory cytokines contributed the most to the observed data variability.