Given the superior results of CD4-IL15/IL15sushi CAR T cells in these in vivo experiments, this construct was then used in a phase I trial against refractory PTCL/CTCL, with the first three patients in the dose escalation trial demonstrating complete remission without the development of severe adverse effects. This evidence concerns the gene IL15 and mature T-cell and NK-cell non-Hodgkin lymphoma.