Type I interferons induce an epigenetically distinct memory B cell subset in chronic viral infection 2024 Cooper et al

Highlights

• scATAC-seq and scRNA-seq reveal expansion of an MBC subset in chronic LCMV infection
• A distinct chronic MBC subset is associated with increased IFN-I-associated ISG signature
• The chromatin landscape of MBCs is established during a critical window early in infection
• IFN-I dynamics govern memory B cell epigenome and phenotype in chronic viral infection

Summary

Memory B cells (MBCs) are key providers of long-lived immunity against infectious disease, yet in chronic viral infection, they do not produce effective protection. How chronic viral infection disrupts MBC development and whether such changes are reversible remain unknown. Through single-cell (sc)ATAC-seq and scRNA-seq during acute versus chronic lymphocytic choriomeningitis viral infection, we identified a memory subset enriched for interferon (IFN)-stimulated genes (ISGs) during chronic infection that was distinct from the T-bet+ subset normally associated with chronic infection. Blockade of IFNAR-1 early in infection transformed the chromatin landscape of chronic MBCs, decreasing accessibility at ISG-inducing transcription factor binding motifs and inducing phenotypic changes in the dominating MBC subset, with a decrease in the ISG subset and an increase in CD11c+CD80+ cells. However, timing was critical, with MBCs resistant to intervention at 4 weeks post-infection. Together, our research identifies a key mechanism to instruct MBC identity during viral infection.

Paywall, https://www.cell.com/immunity/abstract/S1074-7613(24)00137-7