Data from Growth and Activation of Natural Killer Cells <i>Ex Vivo</i> from Children with Neuroblastoma for Adoptive Cell Therapy

Abstract

<div>Abstract<p><b>Purpose:</b> Adoptive transfer of natural killer (NK) cells combined with tumor-specific monoclonal antibodies (mAb) has therapeutic potential for malignancies. We determined if large numbers of activated NK (aNK) cells can be grown <i>ex vivo</i> from peripheral blood mononuclear cells (PBMC) of children with high-risk neuroblastoma using artificial antigen-presenting cells (aAPC).</p><p><b>Experimental Design:</b> Irradiated K562-derived Clone 9.mbIL21 aAPC were cocultured with PBMC, and propagated NK cells were characterized with flow cytometry, cytotoxicity assays, Luminex multicytokine assays, and a nonobese diabetic/severe combined immunodeficient (NOD/SCID) mouse model of disseminated neuroblastoma.</p><p><b>Results:</b> Coculturing patient PBMC with aAPC for 14 days induced 2,363- ± 443-fold expansion of CD56<sup>+</sup>CD3<sup>−</sup>CD14<sup>−</sup> NK cells with 83% ± 3% purity (<i>n</i> = 10). Results were similar to PBMC from normal donors (<i>n</i> = 5). Expression of DNAM-1, NKG2D, FcγRIII/CD16, and CD56 increased 6- ± 3-, 10- ± 2-, 21- ± 20-, and 18- ± 3-fold, respectively, on day 14 compared with day 0, showing activation of NK cells. <i>In vitro</i>, aNK cells were highly cytotoxic against neuroblastoma cell lines and killing was enhanced with GD2-specific mAb ch14.18. When mediating cytotoxicity with ch14.18, release of TNF-α, granulocyte macrophage colony-stimulating factor, IFN-γ, sCD40L, CCL2/MCP-1, CXCL9/MIG, and CXCL11/I-TAC by aNK cells increased 4-, 5-, 6-, 15-, 265-, 917-, and 363-fold (151–9,121 pg/mL), respectively, compared with aNK cells alone. Survival of NOD/SCID mice bearing disseminated neuroblastoma improved when treated with thawed and immediately intravenously infused cryopreserved aNK cells compared with untreated mice and was further improved when ch14.18 was added.</p><p><b>Conclusion:</b> Propagation of large numbers of aNK cells that maintain potent antineuroblastoma activities when cryopreserved supports clinical testing of adoptive cell therapy with ch14.18. <i>Clin Cancer Res; 19(8); 2132–43. ©2013 AACR</i>.</p></div>