Umbilical cord blood: a comprehensive review of protective and restorative properties in clinical applications - a narrative review.

Umbilical cord blood has emerged as a valuable biological resource rich in hematopoietic stem and progenitor cells, offering promising therapeutic potential in regenerative medicine, hematologic disorders, and immune modulation. Compared to bone marrow and peripheral blood stem cells, UCB demonstrates several clinical advantages, including lower risk of graft-versus-host disease (GVHD), increased tolerance for human leukocyte antigen (HLA) mismatch, and rapid availability. Transplantation success rates with UCB have improved significantly, with recent studies reporting overall survival rates of 60-70% in pediatric hematopoietic stem cell transplant recipients and 55-65% in adult recipients, particularly in malignant conditions. The incidence of acute GVHD following UCB transplantation ranges from 20% to 40%, while chronic GVHD occurs in approximately 10-20% of cases - lower than rates observed with other stem cell sources. Moreover, UCB-derived stem cells are being investigated for their regenerative and immunomodulatory capabilities in conditions such as cerebral palsy, type 1 diabetes, and ischemic injury, with early-phase trials showing encouraging safety and efficacy profiles. Despite these advancements, disparities in cost-effectiveness and accessibility remain pressing issues. Public cord blood banks offer greater equity in access and have facilitated most unrelated transplants, whereas private banks, often costly, primarily serve families for autologous use with limited clinical indication. This review provides a comprehensive analysis of the biological underpinnings, clinical applications, and outcomes associated with UCB-based therapies, while highlighting ongoing challenges in global access, standardization, and therapeutic scalability.