Despite the revolutionary achievements of chimeric antigen receptor (CAR) T cell therapy in treating cancers, especially leukemia, several key challenges still limit its therapeutic efficacy. Of particular relevance is the relapse of cancer in large part, as a result of exhaustion and short persistence of CAR-T cells in vivo. IL-2-inducible T cell kinase (ITK) is a critical modulator of the strength of T-cell receptor (TCR) signaling, while its role in CAR signaling is unknown. By electroporation of clustered regularly interspaced short palindromic repeats (CRISPR) associated protein 9 (Cas9) ribonucleoprotein (RNP) complex into CAR-T cells, we successfully deleted ITK in CD19-CAR-T cells with high efficiency. Bulk and single-cell RNA sequencing (scRNA-seq) analyses revealed down-regulation of exhaustion and up-regulation of memory gene signatures in ITK-deficient CD19-CAR-T cells. Our results further demonstrated a significant reduction of T cell exhaustion and enhancement of T cell memory, with significant improvement of CAR-T cell expansion and persistence both in vitro and in vivo. Moreover, ITK-deficient CD19-CAR-T cells showed better control of tumor relapse. Our work provides a promising strategy of targeting ITK to develop sustainable CAR-T products for clinical use.
Zheng Fu, Zineng Huang, Hao Xu, Qingbai Liu, Jing Li, Keqing Song, Yating Deng, Yujia Tao, Huifang Zhang, Peilong Wang, Heng Li, Yue Sheng, Aijun Zhou, Lianbin Han, Yan Fu, Chen-Zhi Wang, Saurav Kumar Choudhary, Kaixiong Ye, Gianluca Veggiani, Zhihong Li, Avery August, Weishan Huang, Qiang Shan, Hongling Peng