Critical role for programmed death 1 signaling and protein kinase B in augmented regulatory T-cell induction in cord blood

摘要

In newboms the induction of productive immune responses is generally blunted in comparison with adults, resulting in toler-ogenic immune reactivity. This immune status results in an increased potency to engraft neonatal animals, ineffective vaccination responses in newborns, and reduced occurrence of graft-versus-host disease when cord blood (CB)-derived allo-grafts are used. We hypothesized that forkhead box protein 3 (FOXP3)-positive regulatory T (Treg) cells are pivotal in this phenomenon because these cells are key players in immune homeostasis.