This article reviews umbilical cord blood transplantation (CBT) supported by co-infusion of adult CD34+ stem cells from mismatched unrelated donors. Through the transient engraftment of the CD34+ cells, CBT recipients experience immune system support until the donated cord blood cells engraft. The authors also discuss the biological characteristics of umbilical cord blood that affect hematopoietic recovery in CBT recipients, including fetal immune system tolerance to foreign antigens, which contributes to a low incidence of GVHD, and the presence of sensitized maternal microchimeric cells, which can induce a graft-versus-leukemia effect.
Van Besien K, et al. Biol Blood Marrow Transplant
Related article: CBT supported by third-party CD34+ cells