Antigen-activated B cells are short lived in the absence of a second signal provided by CD4+ T cells or cytokines. Zikherman and colleagues report that the NR4A family of nuclear receptors (NUR77 and NOR-1) are responsible for enforcing this ‘tolerance’ to self-antigen (signal 1 only) and explain, in part, why B cells are dependent upon a second signal.
- Corey Tan
- Ryosuke Hiwa
- Julie Zikherman