CD40 is a TNF receptor (TNFR) superfamily member which is essential for B cell function.
Cbl-b, an adapter protein and ubiquitin ligase, has been shown to regulate activation of T
and B cells through their antigen receptors. In this study, we report that CD40-induced
proliferation is significantly augmented in mice lacking Cbl-b. Furthermore, Cbl-b−/− mice
display enhanced thymus–dependent (TD) Ab responses and germinal center (GC)
formation, whereas introduction of CD40 deficiency abolishes the hyper-Ab responses and …

It has been documented that CD40 is essential for B cell function. Casitas-B-lineage
lymphoma protein-b (Cbl-b), an adapter protein and ubiquitin ligase, has been shown to
regulate the activation of T and B cells through their Ag receptors. In this study, we report that
CD40-induced B cell proliferation is significantly augmented in mice lacking Cbl-b.
Furthermore, Cbl-b−/− mice display enhanced thymus-dependent Ab responses and
germinal center formation, whereas introduction of CD40 deficiency abolishes these effects …