Donor age matters in T-cell depleted haploidentical hematopoietic stem cell transplantation in pediatric patients: Faster immune reconstitution using younger donors

•Haploidentical transplantation using TCD is associated with encouraging results in children receiving transplant in remission.•Donor selection is a challenge and it should be include variables such as KIR Genotype or age.•Increased number of NK cells in peripheral blood at day +30 is associated with better outcomes.•The use of younger donors is related with improved immune recovery in all lymphocytes populations.

T-cell depleted (TCD) haploidentical transplantation is increasingly used in paediatric patients with haematological malignancies and donor selection is a challenge. We conclude that a simple criterion such as donor age should be also considered in depleted haploidentical setting because faster immune reconstitution is achieved using younger donors decreasing non-relapse related mortality.