Molecular mechanisms of immune cell death in immunosenescence.

Along with organismal aging, multiple compartments of the immune system undergo a progressive functional degeneration that may contribute to - or at least allow for - disease, a scenario that is commonly known as "immunosenescence". While not all immune cell populations suffer from organismal aging through similar mechanisms, immunosenescence appears to involve numerical alterations in specific immune cell types that - at least in some settings - result from the unscheduled activation of regulated cell death (RCD), often along with unbalanced hematopoietic output downstream of thymic involution and bone marrow defects. Here, we critically discuss core RCD mechanisms including apoptosis, necroptosis, ferroptosis, pyroptosis and NETosis as key regulators of global immune homeostasis in the context of immunosenescence.