Pioneering research, presented at the European Society for Organ Transplantation (ESOT) Congress 2023 (September 17-20), opens promising avenues for expanding the organ donor pool and enhancing patient outcomes. By transplanting older donor organs into younger recipients, researchers from Harvard Medical School and the Mayo Clinic investigated the role of transplantation in inducing senescence, a biological mechanism linked to aging and age-related diseases. The researchers conducted age-disparate heart transplants from both young (3 months) and old (18–21 months) mice into younger recipients. Recipients of old hearts showed augmented frequencies of senescent cells in draining lymph nodes, livers, and muscles, in addition to augmented systemic mitochondrial DNA (mtDNA) levels, compared to recipients that received young grafts. Strikingly, transplanting old organs led to advanced physical and cognitive impairments in recipients.