Cancer Immunology, Immunotherapy

, Volume 61, Issue 9, pp 1451–1461

Expression of IL-15 in NK cells results in rapid enrichment and selective cytotoxicity of gene-modified effectors that carry a tumor-specific antigen receptor


  • Christiane Sahm
    • Chemotherapeutisches Forschungsinstitut Georg-Speyer-Haus
  • Kurt Schönfeld
    • Chemotherapeutisches Forschungsinstitut Georg-Speyer-Haus
    • Chemotherapeutisches Forschungsinstitut Georg-Speyer-Haus
Original article

DOI: 10.1007/s00262-012-1212-x

Cite this article as:
Sahm, C., Schönfeld, K. & Wels, W.S. Cancer Immunol Immunother (2012) 61: 1451. doi:10.1007/s00262-012-1212-x


Natural killer (NK) cells hold promise for adoptive cancer immunotherapy but are dependent on cytokines such as interleukin (IL)-2 for growth and cytotoxicity. Here, we investigated the consequences of ectopic expression of IL-15 in human NK cells. IL-2 and IL-15 belong to the common γ chain family of cytokines and have overlapping activities. Transduction of clinically applicable NK-92 cells with lentiviral vectors encoding human IL-15 resulted in predominantly intracellular expression of the cytokine, and STAT5 activation, proliferation and cytotoxicity of the producer cells in the absence of IL-2. Growth of non-transduced bystander cells was not supported, allowing rapid enrichment of gene-modified cells solely by IL-2 withdrawal. This was also the case upon transduction of NK-92 and NKL cells with a bicistronic lentiviral vector encoding IL-15 and a chimeric antigen receptor (CAR) targeting the pancarcinoma antigen EpCAM. Effector cells co-expressing CAR and IL-15 continued to proliferate in the absence of exogenous cytokines and displayed high and selective cell-killing activity against EpCAM-expressing breast carcinoma cells that were resistant to the natural cytotoxicity of unmodified NK cells. This strategy facilitates rapid isolation and continuous expansion of retargeted NK cells and may extend their potential clinical utility.


Interleukin-15Natural killer cellsLentiviral vectorscFv antibodyChimeric antigen receptorEpCAM

Supplementary material

262_2012_1212_MOESM1_ESM.pdf (264 kb)
Supplementary material 1 (PDF 264 kb)

Copyright information

© Springer-Verlag 2012