Antigen-driven EGR2 expression is required for exhausted CD8+ T cell stability and maintenance [ATACseq]

In this study, we examined the role of the transcriptional regulator EGR2 in CD8+ T cell exhaustion during chronic viral infection. Flow cytometric and scRNAseq analysis indicated that EGR2 deficient CD8+ T cells had an abnormal effector-like phenotype. To examine whether this was due to epigenetic alterations, we conducted ATACseq analysis on sorted virus-specific tetramer+ CD8+ T cells isolated at day 20 post-infection with chronic LCMV-Cl13 from either littermate control or EGR2 T cell conditional knock-out mice. The resulting data demonstrated that there were substantial epigenetic changes within EGR2 KO CD8+ T cells, suggesting that EGR2 stabilises the exhausted epigenetic state. The open chromatin regions of exhausted wild-type or EGR2 knockout CD8+ T cells were examined by ATACseq.