Genome wide mapping of chromatin accessibility in resident memory precursor cells [ATAC-seq]

The transcription factor (TF) networks that regulate the differentiation of resident versus circulating memory CD8+ T cells are incompletely understood. Here we show that the TF Bcl11b restricts gut resident memory (Trm) cell differentiation, while promoting splenic T central memory (Tcm) and effector memory (Tem) cell differentiation. The reduction of Bcl11b-deficient splenic Tcm and Tem cells was not due to major alterations in their programs, but rather due to the increased homing of their precursors to the small intestine. However, Bcl11b-deficient resident memory precursor cells upregulated residency program, including the TFs Ahr and Prdm1 (encoding Blimp1), and downregulated Tcf7, which restricts the residency program and promotes tissue egress. Bcl11b directly bound at Ahr and Prdm1, as well as at Tcf7 genes. Abrogating Ahr and Prdm1, or restoration of Tcf7 expression in Bcl11b-deficient cells led to partial correction of the excessive resident memory cell differentiation. Functionally, Bcl11b-deficient memory CD8+ T cells had an impaired recall response, but anti-tumor immunity was increased in adoptive cell therapy. Bcl11b also repressed the residency program in human CD8+ T cells and human Bcl11b low tumor-infiltrating lymphocytes showed increased residency gene expression. Thus, Bcl11b plays a critical role in balancing the circulating and tissue residency programs and reveals a potential novel target for cancer immunotherapies. Examination of changes to chromatin accessibility in resident memory precursor cells caused by the removal of Bcl11b.