Fig. 7: Cytokine patterns in the basal state and in response to an injury showed increased reactivity in immunoaged mice.

Systemic cytokine levels in the blood were screened pre-surgery and 3 days post-surgery for immunoaged and less-experienced (aged) 12-month-old mice. The cytokine levels in the basal state revealed an inflammaged status in immunoaged mice, as indicated by increased systemic levels of TNFα, IL-6, and IL-10. Upon activation due to osteotomy, the cytokine levels varied based on the immune experience level: Increased levels of IL-22, GM-CSF, and IL-1b could be observed in immunoaged mice. Most importantly, IL-22 not only showed high basal expression levels in immunoaged compared to aged mice but also appeared to react distinctly in the respective immunoaged phenotype, with a significant downregulation upon injury in aged mice but an increase upon injury in immunoaged mice. N = 4 per group; bar plot with SD; Welch’s t-test; black * = between immunological experience groups, gray * = between untreated and osteotomized groups.