Nuclear receptor Nr4a1 modulates both regulatory T-cell (Treg) differentiation and clonal deletion
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
Authors: Fassett, Marlys S.; Jiang, Wenyu; D'Alise, Anna Morena; Mathis, Diane; Benoist, Christophe
Abstract
Immature thymocytes expressing autoreactive T-cell receptors (TCR) can adopt differing cell fates: clonal deletion by apoptosis or deviation into alternative lineages such as FoxP3(+) regulatory T cells (Treg). We revisited the role of the transcription factor Nr4a1 (Nur77), an immediate-early response gene induced by TCR engagement. Nr4a1KO mice show clear quantitative defects in antigen-induced clonal deletion. The impact of the Nr4a1 deletion is not enhanced by deletion of the proapoptotic factor Bim. In addition, Nr4a1 curtails initial differentiation into the Treg lineage in TCR transgenic mice and in nontransgenic mice. Transcriptional profiling of Nr4a1KO thymocytes under selection conditions reveals that Nr4a1 activates the transcription of several targets, consistent with these diverse actions: (i) Nr4a1 partakes in the induction of Bim after TCR triggering; (ii) perhaps paradoxically, Nr4a1 positively controls several transcripts of the Treg signature, in particular Ikzf2 and Tnfrsf9; (iii) consistent with its prosurvival and metabolic role in the liver, Nr4a1 is also required for the induction by TCR of a coordinated set of enzymes of the glycolytic and Krebs cycle pathways, which we propose may antagonize Treg selection as does activation of mTOR/Akt. Thus, Nr4a1 appears to act as a balancing molecule in fate determination at a critical juncture of T-cell differentiation.
Recent Advances in Allogeneic CAR-T Cells
BIOMOLECULES
Authors: Kim, Dong Wook; Cho, Je-Yoel
Abstract
In recent decades, great advances have been made in the field of tumor treatment. Especially, cell-based therapy targeting tumor associated antigen (TAA) has developed tremendously. T cells were engineered to have the ability to attack tumor cells by generating CAR constructs consisting of genes encoding scFv, a co-stimulatory domain (CD28 or TNFRSF9), and CD247 signaling domains for T cell proliferation and activation. Principally, CAR-T cells are activated by recognizing TAA by scFv on the T cell surface, and then signaling domains inside cells connected by scFv are subsequently activated to induce downstream signaling pathways involving T cell proliferation, activation, and production of cytokines. Many efforts have been made to increase the efficacy and persistence and also to decrease T cell exhaustion. Overall, allogeneic and universal CAR-T generation has attracted much attention because of their wide and prompt usage for patients. In this review, we summarized the current techniques for generation of allogeneic and universal CAR-T cells along with their disadvantages and limitations that still need to be overcome.