B-1 B cells lose self-control in SCD

In this issue of Blood, Su et al report that patients with sickle cell disease (SCD) have elevated quantities of a subset of B cells (B-1 cells), which significantly correlates with red blood cell (RBC) autoantibody levels. They also show that antiviral cytokines, type 1 interferons (IFN-Is), contribute to alterations in B-1 cell subsets, T-cell-independent antibody responses, and RBC autoantibody production in SCD mice (see figure). Although it has been shown that patients with SCD have an elevated frequency of RBC autoanti-bodies,2 mechanisms contributing to this frequency are lacking and represent one of the preeminent questions in the field.