ATAC-seq Reveals that Heme Regulates the Transcriptional Activity of Transcription Factors Driving CD8? T Cell Exhaustion

Regulatory heme is known to influence cellular behavior by modulating the activity of hemoproteins. We hypothesized that elevated levels of regulatory heme might drive T cell exhaustion through the modulation of transcription factor activity. To test this hypothesis, we first confirmed that treatment with hemin, a heme analog, effectively increased intracellular regulatory heme levels in T cells. To assess the transcriptional and chromatin changes induced by hemin, we performed ATAC-seq on CD8? T cells treated with or without exogenous hemin. The ATAC-seq analysis revealed that hemin-treated T cells displayed a distinct chromatin accessibility landscape compared to vehicle-treated controls. Integration of ATAC-seq and transcriptomic data using the Taiji analytical algorithm revealed that hemin modulates the activity of transcription factors involved in T cell exhaustion, including BACH2, MYB, MAF, BATF, RUNX3, and PRDM1. Overall design: Primary normal CD8 T cell treated with 25uM Hemin or veicle for bulk ATAC-seq analysis, 4 replicates are included in each group.