T cells targeting a KRAS mutation can induce durable tumor regression in some patients with metastatic epithelial cancer. It is unknown whether T cells targeting mutant KRAS that are capable of killing tumor cells can be identified from peripheral blood of patients with pancreatic cancer. We developed an in vitro stimulation approach and identified HLA-A*11:01–restricted KRAS G12V–reactive CD8+ T cells and HLA-DRB1*15:01–restricted KRAS G12V–reactive CD4+ T cells from peripheral blood of 2 out of 6 HLA-A*11:01–positive patients with pancreatic cancer whose tumors expressed KRAS G12V. The HLA-A*11:01–restricted KRAS G12V–reactive T cell receptor (TCR) was isolated and validated to specifically recognize the KRAS G12V8–16 neoepitope. While T cells engineered to express this TCR specifically recognized all 5 tested human HLA-A*11:01+ and KRAS G12V+ pancreatic cancer organoids, the recognition was often modest, and tumor cell killing was observed in only 2 out of 5 organoids. IFN-γ priming of the organoids enhanced the recognition and killing by the TCR-engineered T cells. The TCR-engineered T cells could significantly slow the growth of an established organoid-derived xenograft in immunodeficient mice. Our data suggest that this TCR has potential for use in TCR-gene therapy, but additional strategies that enhance tumor recognition by the TCR-engineered T cells likely will be required to increase clinical activity.
Xiongfei Xu, Shiwei Guo, Haihui Gu, Zhanshan Cha, Xiaohan Shi, Xiaoyi Yin, Huan Wang, Suizhi Gao, Bo Li, Lingyu Zhu, Wei Jing, Kailian Zheng, Zhuo Shao, Peng Cheng, Chunhong Zheng, Yi-Ping Shih, Yunguang Li, Baohua Qian, Dong Gao, Eric Tran, Gang Jin
This file is in Adobe Acrobat (PDF) format. If you have not installed and configured the Adobe Acrobat Reader on your system.
PDFs are designed to be printed out and read, but if you prefer to read them online, you may find it easier if you increase the view size to 125%.
Many versions of the free Acrobat Reader do not allow Save. You must instead save the PDF from the JCI Online page you downloaded it from. PC users: Right-click on the Download link and choose the option that says something like "Save Link As...". Mac users should hold the mouse button down on the link to get these same options.