Project description:During persistent antigen stimulation, CD8+ cytolytic T cells (CTL) show a gradual decrease in effector function, or “exhaustion”, which impairs the immune response to tumors and infections. Here we show that NFAT, a transcription factor with an established role in T cell activation, in parallel controls a second transcriptional program conferring the characteristic features of CD8+ T cell exhaustion, including upregulation of genes encoding inhibitory cell surface receptors and diminished TCR signaling. Expression of an engineered NFAT1, which induces this negative regulatory program in the absence of the effector program, interferes with the ability of CD8+ T cells to protect against Listeria infection or attenuate tumor growth in vivo. NFAT elicits this second program of gene expression in large part by binding to a subset of the sites occupied by NFAT during a typical effector response, suggesting that a balance between the two pathways determines the outcome of TCR signaling. Understanding the role of CA-RIT-NFAT1 in T cells
Project description:During persistent antigen stimulation, CD8+ cytolytic T cells (CTL) show a gradual decrease in effector function, or “exhaustion”, which impairs the immune response to tumors and infections. Here we show that NFAT, a transcription factor with an established role in T cell activation, in parallel controls a second transcriptional program conferring the characteristic features of CD8+ T cell exhaustion, including upregulation of genes encoding inhibitory cell surface receptors and diminished TCR signaling. Expression of an engineered NFAT1, which induces this negative regulatory program in the absence of the effector program, interferes with the ability of CD8+ T cells to protect against Listeria infection or attenuate tumor growth in vivo. NFAT elicits this second program of gene expression in large part by binding to a subset of the sites occupied by NFAT during a typical effector response, suggesting that a balance between the two pathways determines the outcome of TCR signaling. Determination of NFAT1 binding sites in CD8 T cells in vitro
Project description:During persistent antigen stimulation, CD8+ cytolytic T cells (CTL) show a gradual decrease in effector function, or “exhaustion”, which impairs the immune response to tumors and infections. Here we show that NFAT, a transcription factor with an established role in T cell activation, in parallel controls a second transcriptional program conferring the characteristic features of CD8+ T cell exhaustion, including upregulation of genes encoding inhibitory cell surface receptors and diminished TCR signaling. Expression of an engineered NFAT1, which induces this negative regulatory program in the absence of the effector program, interferes with the ability of CD8+ T cells to protect against Listeria infection or attenuate tumor growth in vivo. NFAT elicits this second program of gene expression in large part by binding to a subset of the sites occupied by NFAT during a typical effector response, suggesting that a balance between the two pathways determines the outcome of TCR signaling.
Project description:During persistent antigen stimulation, CD8+ cytolytic T cells (CTL) show a gradual decrease in effector function, or “exhaustion”, which impairs the immune response to tumors and infections. Here we show that NFAT, a transcription factor with an established role in T cell activation, in parallel controls a second transcriptional program conferring the characteristic features of CD8+ T cell exhaustion, including upregulation of genes encoding inhibitory cell surface receptors and diminished TCR signaling. Expression of an engineered NFAT1, which induces this negative regulatory program in the absence of the effector program, interferes with the ability of CD8+ T cells to protect against Listeria infection or attenuate tumor growth in vivo. NFAT elicits this second program of gene expression in large part by binding to a subset of the sites occupied by NFAT during a typical effector response, suggesting that a balance between the two pathways determines the outcome of TCR signaling.
Project description:Complex regulatory mechanisms control continuous maintenance of myeloid progenitors and renewal of differentiated cells. Transcription factors play a important role in these processes. Here we report that the activation the calcineurin-NFAT signaling pathway inhibit the proliferation of myeloid granulocyte-monocyte progenitor (GMP). Myeloid progenitor subtypes possessed different susceptibilities to Ca2+ flux induction and consequently differential engagement of the calcineurin-NFAT pathway. This study show that inhibition of the calcineurin-NFAT pathway enhanced proliferation of GMPs both in vivo and in vitro. The calcineurin-NFAT signaling in GMPs is initiated through Flt3-L. The inhibition of the calcineurin-NFAT pathway altered the expression of the cell cycle regulation genes CDK4, CDK6, and CDKN1A, thus enabling faster cell cycle progression. The extensive use of NFAT inhibitors in the clinic should take into account that, in addition to the immunosuppression role in lymphoid cells, these NFAT inhibitors also affect the maintenance of the myeloid compartment. Microarray technology was used to understand the effects of NFAT inhibitors on C-kit enriched lineage negative cells.