We recently found an important protective role for BAFF in atherosclerosis, which we suggest acted via macrophage-expressed TACI (transmembrane activator and CAML interactor)31; this provides an alternative mechanism for the protective effect of B cell depletion, which results in high BAFF levels.30 In Btg mice, BAFF levels were lower than in control mice (Figure IVE in the online-only Data Supplement). This evidence concerns the gene TNFRSF13B and atherosclerosis.