T-bet high and low sorted CD4 T cells after acute infection

The purpose of this study was to understand in detail how T-bet+ CD4 T cells differ depending on their quantitative T-bet levels after acute LCMV infection. For this, the murine T-bet ZsGreen reporter system was used for sorting cells ex vivo without manipulation according to their T-bet brightness into high and low expressors. The bulk RNA Sequencing of these cells showed that T-bet high cells (n=3) have a rather cytotoxic profile, while T-bet low cells (n=3) upregulate multiple Tfh associated markers while still strongly depicting a Th1 phenotype. Overall, only up to 5% of the expressed genes differed between high and low expressors. Furthermore, the bulk ATAC-sequencing also confirmed strong overlap in chromatin accessability of high (n=2) and low (n=2) expressors. Only a couple of the highly differentially expressed genes from the RNA-Seq data also showed differences in chromatin accessability at the TSS. This study provides a further insight into the quantitative differences of T-bet expressing CD4 T cells.