Impaired thymopoiesis predicts for a high risk of severe infections after reduced intensity conditioning without anti-thymocyte globulin in double umbilical cord blood transplantation.

Umbilical cord blood stem cell transplantation (UCBT) is associated with retarded hematopoietic recovery and immune reconstitution and a high infection-related morbidity and mortality, especially after conditioning including anti-thymocyte globulin (ATG). However, data on immune recovery, incidence of infections, and outcome in double UCBT (dUCBT) recipients receiving an ATG-free reduced intensity conditioning (RIC) are lacking. In this study, recovery of lymphocyte subsets, thymopoiesis, and its association with severe infections and clinical outcome was assessed in a group of 55 recipients of a dUCBT ATG-free RIC regimen.

Keratinocyte growth factor and stem cell factor to improve thymopoiesis after autologous CD34+ cell transplantation in rhesus macaques.

Deficient thymopoiesis and retarded recovery of naive CD4(+) T cells are important determinants of insufficient immune-competence following hematopoietic stem cell transplantation (HSCT). Although keratinocyte growth factor (KGF) may protect the thymic epithelium, stem cell factor (SCF) is involved in early thymopoiesis. We evaluated whether KGF alone or combined with SCF would affect thymopoiesis and hematologic recovery following myeloablative autologous HSCT into rhesus macaques.