TY - JOUR
T1 - Transgenic expression of IL15 improves antiglioma activity of IL13Rα2-CAR T cells but results in antigen loss variants
AU - Krenciute, Giedre
AU - Prinzing, Brooke L.
AU - Yi, Zhongzhen
AU - Wu, Meng Fen
AU - Liu, Hao
AU - Dotti, Gianpietro
AU - Balyasnikova, Irina V.
AU - Gottschalk, Stephen
N1 - Funding Information:
This work was supported by NIH Grants 1R01CA173750-01 and 1R21NS089802-01, NCI Cancer Center Support grant P30CA125123, American Brain Tumor Association Basic Research Fellowship in the honor of Joel A. Gingras Jr. (BRF160004), Alex Lemonade Stand Foundation, Curing Kids Cancer, Cookies for Kids Cancer, and the James S. McDonnell Foundation.
Publisher Copyright:
© 2017 American Association for Cancer Research.
PY - 2017/7
Y1 - 2017/7
N2 - Glioblastoma (GBM) is the most aggressive primary brain tumor in adults and is virtually incurable with conventional therapies. Immunotherapy with T cells expressing GBM-specific chimeric antigen receptors (CAR) is an attractive approach to improve outcomes. Although CAR T cells targetingGBMantigens, such as IL13 receptor subunit α2 (IL13Rα2), HER2, and EGFR variant III (EGFRvIII), have had antitumor activity in preclinical models, early-phase clinical testing has demonstrated limited antiglioma activity. Transgenic expression of IL15 is an appealing strategy to enhance CAR T-cell effector function. We tested this approach in our IL13Rα2-positive glioma model in which limited IL13Rα2-CAR T-cell persistence results in recurrence of antigenpositive gliomas. T cells were genetically modified with retroviral vectors encoding IL13Rα2-CARs or IL15 (IL13Rα2-CAR.IL15 T cells). IL13Rα2-CAR.IL15 T cells recognized glioma cells in an antigen-dependent fashion, had greater proliferative capacity, and produced more cytokines after repeated stimulations in comparison with IL13Rα2-CAR T cells. No autonomous IL13Rα2-CAR. IL15 T-cell proliferation was observed; however, IL15 expression increased IL13Rα2-CAR T-cell viability in the absence of exogenous cytokines or antigen. In vivo, IL13Rα2-CAR.IL15 T cells persisted longer and had greater antiglioma activity than IL13Rα2-CAR T cells, resulting in a survival advantage. Gliomas recurring after 40 days after T-cell injection had downregulated IL13Rα2 expression, indicating that antigen loss variants occur in the setting of improved T-cell persistence. Thus, CAR T cells for GBM should not only be genetically modified to improve their proliferation and persistence, but also to target multiple antigens. Summary: Glioblastoma responds imperfectly to immunotherapy. Transgenic expression of IL15 in T cells expressing CARs improved their proliferative capacity, persistence, and cytokine production. The emergence of antigen loss variants highlights the need to target multiple tumor antigens. Cancer Immunol Res; 5(7); 571-81.
AB - Glioblastoma (GBM) is the most aggressive primary brain tumor in adults and is virtually incurable with conventional therapies. Immunotherapy with T cells expressing GBM-specific chimeric antigen receptors (CAR) is an attractive approach to improve outcomes. Although CAR T cells targetingGBMantigens, such as IL13 receptor subunit α2 (IL13Rα2), HER2, and EGFR variant III (EGFRvIII), have had antitumor activity in preclinical models, early-phase clinical testing has demonstrated limited antiglioma activity. Transgenic expression of IL15 is an appealing strategy to enhance CAR T-cell effector function. We tested this approach in our IL13Rα2-positive glioma model in which limited IL13Rα2-CAR T-cell persistence results in recurrence of antigenpositive gliomas. T cells were genetically modified with retroviral vectors encoding IL13Rα2-CARs or IL15 (IL13Rα2-CAR.IL15 T cells). IL13Rα2-CAR.IL15 T cells recognized glioma cells in an antigen-dependent fashion, had greater proliferative capacity, and produced more cytokines after repeated stimulations in comparison with IL13Rα2-CAR T cells. No autonomous IL13Rα2-CAR. IL15 T-cell proliferation was observed; however, IL15 expression increased IL13Rα2-CAR T-cell viability in the absence of exogenous cytokines or antigen. In vivo, IL13Rα2-CAR.IL15 T cells persisted longer and had greater antiglioma activity than IL13Rα2-CAR T cells, resulting in a survival advantage. Gliomas recurring after 40 days after T-cell injection had downregulated IL13Rα2 expression, indicating that antigen loss variants occur in the setting of improved T-cell persistence. Thus, CAR T cells for GBM should not only be genetically modified to improve their proliferation and persistence, but also to target multiple antigens. Summary: Glioblastoma responds imperfectly to immunotherapy. Transgenic expression of IL15 in T cells expressing CARs improved their proliferative capacity, persistence, and cytokine production. The emergence of antigen loss variants highlights the need to target multiple tumor antigens. Cancer Immunol Res; 5(7); 571-81.
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U2 - 10.1158/2326-6066.CIR-16-0376
DO - 10.1158/2326-6066.CIR-16-0376
M3 - Article
C2 - 28550091
AN - SCOPUS:85021919065
VL - 5
SP - 571
EP - 581
JO - Cancer immunology research
JF - Cancer immunology research
SN - 2326-6066
IS - 7
ER -