Pediatric Blood & Cancer, December 2016, Vol.63(12), pp.2230-2239
To purchase or authenticate to the full-text of this article, please visit this link: http://onlinelibrary.wiley.com/doi/10.1002/pbc.26147/abstract Byline: Claudia Cappel, Sabine Huenecke, Anica Suemmerer, Stephanie Erben, Eva Rettinger, Verena Pfirrmann, Annekathrin Heinze, Olga Zimmermann, Thomas Klingebiel, Evelyn Ullrich, Peter Bader, Melanie Bremm Keywords: CIK (cytokine-induced killer) cells; immunotherapy; neuroblastoma Abstract Background Neuroblastoma (NB) is the most common solid extracranial tumor in childhood. Despite advances in therapy, the prognosis is poor and optimized therapies are urgently needed. Therefore, we investigated the antitumor potential of interleukin-15 (IL-15)-activated cytokine-induced killer (CIK) cells against different NB cell lines. Procedure CIK cells were generated from peripheral blood mononuclear cells by the stimulation with interferon-[gamma] (IFN-[gamma]), IL-2, OKT-3 and IL-15 over a period of 10-12 days. The cytotoxic activity against NB cells was analyzed by nonradioactive Europium release assay before and after blocking of different receptor-ligand interactions relevant in CIK cell-mediated cytotoxicity. Results The final CIK cell products consisted in median of 83% (range: 75.9-91.9%) CD3.sub.+CD56.sub.- T cells, 14% (range: 5.2-20.7%) CD3.sub.+CD56.sub.+ NK-like T cells and 2% (range: 0.9-4.8%) CD3.sub.-CD56.sub.+ NK cells. CIK cells expanded significantly upon ex vivo stimulation with median rates of 22.3-fold for T cells, 58.3-fold for NK-like T cells and 2.5-fold for NK cells. Interestingly, CD25 surface expression increased from less than equal to 1% up to median 79.7%. Cytotoxic activity of CIK cells against NB cells was in median 34.7, 25.9 and 34.8% against the cell lines UKF-NB-3, UKF-NB-4 and SK-N-SH, respectively. In comparison with IL-2-stimulated NK cells, CIK cells showed a significantly higher cytotoxicity. Antibody-mediated blocking of the receptors NKG2D, TRAIL, FasL, DNAM-1, NKp30 and lymphocyte function-associated antigen-1 (LFA-1) significantly reduced lytic activity, indicating that diverse cytotoxic mechanisms might be involved in CIK cell-mediated NB killing. Conclusions Unlike the mechanism reported in other malignancies, NKG2D-mediated cytotoxicity does not constitute the major killing mechanism of CIK cells against NB. Article Note: Claudia Cappel and Sabine Huenecke contributed equally to the manuscript.
Cik Cytokine‐Induced Killer Cells ; Immunotherapy ; Neuroblastoma