The activation mechanism of chimeric antigen receptor (CAR)-engineered T cells may differ substantially from T cells carrying native T cell receptor,but this difference remains poorly understood. We present the first ...The activation mechanism of chimeric antigen receptor (CAR)-engineered T cells may differ substantially from T cells carrying native T cell receptor,but this difference remains poorly understood. We present the first comprehensive portrait of single-cell level transcriptional and cyto-kine signatures of anti-CD19/4-1BB/CD28/CD3ζ CAR-T cells upon antigen-specific stimulation. Both CD4+helper T (TH) cells and CD8+cytotoxic CAR-T cells are equally effective in directly killing target tumor cells and their cytotoxic activity is associated with the elevation of a range of TH1 and TH2 signature cytokines,e.g.,interferon γ,tumor necrotic factor α,interleukin 5 (IL5),and IL13,as confirmed by the expression of master transcription factor genes TBX21 and GATA3. However,rather than conforming to stringent TH1 or TH2 subtypes,single-cell analysis reveals that the predominant response is a highly mixed TH1/TH2 function in the same cell. The reg-ulatory T cell activity,although observed in a small fraction of activated cells,emerges from this hybrid TH1/TH2 population. Granulocyte-macrophage colony stimulating factor (GM-CSF) is pro-duced from the majority of cells regardless of the polarization states,further contrasting CAR-T to classic T cells. Surprisingly,the cytokine response is minimally associated with differentiation status,although all major differentiation subsets such as na?ve,central memory,effector memory,and effector are detected. All these suggest that the activation of CAR-engineered T cells is a canon-ical process that leads to a highly mixed response combining both type 1 and type 2 cytokines together with GM-CSF,supporting the notion that polyfunctional CAR-T cells correlate with objective response of patients in clinical trials. This work provides new insights into the mechanism of CAR activation and implies the necessity for cellular function assays to characterize the quality of CAR-T infusion products and monitor therapeutic responses in patients.展开更多
基金supported by the Packard Fellowship for Science and Engineering, the CAREER award from the National Science Foundation (NSF), United States (Grant No. CBET-1351443)the grants from National Institutes of Health (NIH), United States (Grant No. U54 CA193461 and Sub-Project 7297 of Grant No. U54 CA209992)+1 种基金the CoPilot Grant from Yale Cancer Center, United States, to RFsupported by National Institutes of Health, United States (NIH U54DK106857)
文摘The activation mechanism of chimeric antigen receptor (CAR)-engineered T cells may differ substantially from T cells carrying native T cell receptor,but this difference remains poorly understood. We present the first comprehensive portrait of single-cell level transcriptional and cyto-kine signatures of anti-CD19/4-1BB/CD28/CD3ζ CAR-T cells upon antigen-specific stimulation. Both CD4+helper T (TH) cells and CD8+cytotoxic CAR-T cells are equally effective in directly killing target tumor cells and their cytotoxic activity is associated with the elevation of a range of TH1 and TH2 signature cytokines,e.g.,interferon γ,tumor necrotic factor α,interleukin 5 (IL5),and IL13,as confirmed by the expression of master transcription factor genes TBX21 and GATA3. However,rather than conforming to stringent TH1 or TH2 subtypes,single-cell analysis reveals that the predominant response is a highly mixed TH1/TH2 function in the same cell. The reg-ulatory T cell activity,although observed in a small fraction of activated cells,emerges from this hybrid TH1/TH2 population. Granulocyte-macrophage colony stimulating factor (GM-CSF) is pro-duced from the majority of cells regardless of the polarization states,further contrasting CAR-T to classic T cells. Surprisingly,the cytokine response is minimally associated with differentiation status,although all major differentiation subsets such as na?ve,central memory,effector memory,and effector are detected. All these suggest that the activation of CAR-engineered T cells is a canon-ical process that leads to a highly mixed response combining both type 1 and type 2 cytokines together with GM-CSF,supporting the notion that polyfunctional CAR-T cells correlate with objective response of patients in clinical trials. This work provides new insights into the mechanism of CAR activation and implies the necessity for cellular function assays to characterize the quality of CAR-T infusion products and monitor therapeutic responses in patients.