The role of T-bet in B cells

We read with interest the recent paper by Liu et al. describing the observation that immunostimulatory CpG oligonucleotides induce the transcription factor T-bet in B cells, apparently leading to the suppression of immunoglobulin G1 (IgG1) and IgE isotype switching1. We were particularly interested in the potential implications of this observation to the pathogenesis of humoral autoimmunity, which seems to involve critical interactions between CpG sequences, Toll-like receptor 9 (TLR9) and T-bet2, 3, 4.