Longevity & AgingHuman Immune Atlas Maps How Immunity Rewires Itself Before Old Age
Researchers at the Allen Institute for Immunology profiled peripheral immunity in over 300 healthy adults aged 25–90 using single-cell RNA sequencing, proteomics, and flow cytometry, following 96 individuals longitudinally for two years with annual flu vaccination. The resulting Human Immune Health Atlas — encompassing more than 16 million peripheral blood mononuclear cells across 71 immune cell subsets — revealed robust, non-linear transcriptional reprogramming in T cells that begins well before advanced age. Crucially, this reprogramming drove a functional TH2 bias in memory T cells, which was linked to dysregulated B cell responses against highly boosted influenza vaccine antigens. These changes were independent of systemic inflammation or cytomegalovirus infection, identifying novel, age-intrinsic immune mechanisms as targets for intervention.
