Recent studies indicate that immature B cells compete with recirculati
ng B cells for survival signals. The signals, delivered through the B-
cell receptor for antigen, induce immature cells to differentiate into
recirculating cells and maintain the survival of recirculating cells.
They do not induce proliferation or differentiation to antibody-produ
cing cells. (C) Current Biology Ltd ISSN 0952-7915.