IL-15 plays an essential role in the regulation of the development and activation of NK cells.734 In patients with non-Hodgkin’s lymphomas, high concentrations of serum IL-15 following autologous peripheral blood hematopoietic stem cell transplantation (APHSCT) were associated with better survival.735 In addition, systemic administration of recombinant IL-15 could stimulate the activity of NK cells. This evidence concerns the gene IL15 and non-Hodgkin lymphoma.