Use of common γ chain cytokines for the visualization, isolation and genetic modification of memory T lymphocytes

An in vitro method for obtaining a genetically modified memory T cell population that is CD4+ or CD8+, comprising the steps of:

• a) activating lymphocytes in vitro in a cell-free medium with at least two specific activating receptor agonist antibodies that are able to drive lymphocyte activation, wherein one of the lymphocyte activating receptor agonist antibodies is specific for CD3 polypeptide and the other lymphocyte activating receptor agonist antibody is specific for CD28;
• b) exposing activated lymphocytes in vitro, in a cell-free medium, to an effective amount of interleukin added to the medium, wherein the interleukin is at least IL-7 and IL-15, able to selectively expand populations of memory T cells;
• and
• c) inserting and expressing an exogenous gene by means of an appropriate vector into the lymphocytes as obtained in b) to produce a genetically modified memory T cell population that is CD4+ or CD8+;
• wherein the effective amount of the interleukin added to the medium is from 5 ng/ml to 50 ng/ml;
• wherein the medium and interleukin of step b) are replaced every 3 to 4 days;
• and
• wherein about 80% of both CD8+ and CD4+T− cells of steps b) and c) are positive for the marker CD62L and marker CD127 and are central memory T-lymphocytes.