Over the past several decades, B cell antigen receptor (BCR)-induced signaling pathways have been described in extraordinary molecular detail, mainly from studies of B cell responses to antigens in vitro. BCR signaling has been shown to govern the initiation of transcriptional programs associated with B cell activation and fate decisions, as well as the BCR-dependent processing of antigen and presentation of antigen to T cells. However, although the potential of the BCR to orchestrate B cell behavior was known, there was no clear appreciation of the context in which B cells signal in secondary lymphoid organs in vivo or how that context influences signaling. In this Review, we describe the current view of the cellular consequences of BCR signaling and advances in the understanding of B cell signaling in context in vivo.
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Supported by the Intramural Research Program of the National Institute of Allergy and Infectious Diseases of the US National Institutes of Health. The authors thank R. Kissinger (of that institution) for expert preparation of the illustrations presented here.
The authors declare no competing interests.
Peer review information: Laurie A. Dempsey was the primary editor on this article and managed its editorial process and peer review in collaboration with the rest of the editorial team.
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