Engineering γδT cells limits tonic signaling associated with chimeric antigen receptors.

Engineering γδT cells limits tonic signaling associated with chimeric antigen receptors. Sci Signal. 2019 Sep 10;12(598): Authors: Fisher J, Sharma R, Don DW, Barisa M, Hurtado MO, Abramowski P, Porter L, Day W, Borea R, Inglott S, Anderson J, Pe'er D Abstract Despite the benefits of chimeric antigen receptor (CAR)-T cell therapies against lymphoid malignancies, responses in solid tumors have been more limited and off-target toxicities have been more marked. Among the possible design limitations of CAR-T cells for cancer are unwanted tonic (antigen-independent) signaling and off-target activation. Efforts to overcome these hurdles have been blunted by a lack of mechanistic understanding. Here, we showed that single-cell analysis with time course mass cytometry provided a rapid means of assessing CAR-T cell activation. We compared signal transduction in expanded T cells to that in T cells transduced to express second-generation CARs and found that cell expansion enhanced the response to stimulation. However, expansion also induced tonic signaling and reduced network plasticity, which were associated with expression of the T cell exhaustion markers PD-1 and TIM-3. Because this was most evident in pathways downstream of CD3ζ, we performed similar analyses on γδT cells that expressed chimeric costimulatory receptors (CCRs) lacking CD3ζ but containing DAP10 stimulatory domains. These CCR-γδT cells did not exhibit tonic signaling b...
Source: Science Signaling - Category: Biomedical Science Authors: Tags: Sci Signal Source Type: research