Immunoproteasome remodeling in senescing human macrophages reveals the loss of PA28αβ capping as a hallmark of immunosenescence

We established an in vitro model of blood monocyte-derived human macrophages that acquire a senescent-like phenotype upon long-term culture. Using this model, we investigated how the proteome is remodeled during senescence by analyzing cell extracts at 7 days (mature macrophages), 14 days (onset of senescence), and 28 days (fully senescent.)