Modeling Hematopoietic Aging Through Murine Bone Marrow Transplantation
Bejarano-García JA, Nufer M, Caracuel R, et al. Integrated Analysis of Hematopoietic Changes Following Heterochronic Bone Marrow Transplantation Between Young and Aged Mice. Transplantation and Cellular Therapy. 2026; (doi: 10.1016/j.jtct.2026.09.011).
To describe the systematic effect of aging on hematopoiesis, researchers transplanted bone marrow (BM) cells to and from both young and very aged mice. Assessment 6 months later, by comparison with age-matched controls not subjected to transplant, confirmed that hematopoietic aging mediates greater accumulation of hematopoietic stem cells but hinders their fitness and function, affects immune exhaustion, promotes T-cell memory skewing, and is implicated in myeloid bias, among other impacts. How these changes manifest hinges on a combination of donor age, recipient environment, and stress tied to the transplant itself, which is known for its role in hematopoietic reconstitution. Unlike previous work that presented heterochronic BM transplantation study results as isolated outcomes within simplified contexts, the current investigation demonstrates these phenomena across different lineages — including B cells, conventional T cells, regulatory T cells, and naïve/memory T cells — and anatomical locations. The findings could inform strategies for enhancing hematopoietic regeneration and immune competence post-transplantation, the researchers report.