Comparison of Bach2-tdRFP high expression and low expression NP-specific IgG1 light zone GC B cells. Mus musculus

Despite the importance of memory B cells for protection from recurrent infection, how these cells are selected during germinal center (GC) reactions remains unclear. We show here that light zone (LZ) GC B cells with lower affinity BCRs express a less CD40 signature and relatively high levels of Bach2, being prone to enter the memory B cell pool. We also find that Bach2 contributes to memory B cell generation in a Blimp-1-independent manner and that its higher expression confers on LZ GC cells a more advantage for entering the memory B cell compartment. Thus, our data support an instructive model in which weak T cell help keep Bach2 expression relatively high, thereby being predisposed to enter the memory pool. Overall design: mRNA expression profiles of Bach2-tdRFP low and high expression NP-specific IgG1 light zone GC B cells were generated by deep sequencing using Illumina HiSeq 1500.