Single-Cell RNA Sequencing Reveals that Bach2 with Inactive Heme-Binding Sites Sustains the Stemness of CD8+ T Cells

Bach2 is vital for the formation of progenitor exhausted T cells and for maintaining their stem-like properties. In B cells, Bach2 undergoes conformational changes that reduce its transcriptional repression activity due to decreased DNA-binding affinity and increased degradation, subsequently triggering Blimp1 expression. Therefore, we aimed to use scRNA-seq to determine whether mutation of the heme-binding site in Bach2 (Bach2MUT) could more efficiently preserve stem-like properties in tumor-infiltrating lymphocytes (TILs) compared to wild-type Bach2 (Bach2WT). Overall design: P14 cells were isolated from P14 mice and then overexpressed with either Bach2WT (CD45.1) or Bach2MUT (CD45.1/.2). The cells were co-transferred into Yumm1.7-gp33 tumor-bearing mice. Nine days later, CD3+CD8+CD44+CD45.1 or CD3+CD8+CD44+CD45.1/.2 cells were sorted and subjected to CMO multiplexing followed by scRNA-seq.