Direct regulation of T cell exhaustion by NFAT [ChIP-Seq]

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