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B Cell Receptor Crosslinking Augments Germinal Center B Cell Selection when T Cell Help Is Limiting.

ABSTRACT: Antigen-dependent engagement of germinal center (GC) B cell receptors (BCRs) promotes antigen internalization and presentation for follicular helper T cells. However, whether BCR signaling is critical or synergistic with T cell help for GC B cell selection or differentiation is unclear. Here, by adapting an experimental approach that enables independent delivery of BCR-crosslinking antigen or T cell help to GC B cells in vivo, we showed that T cell help was sufficient to induce GC B cell expansion and plasmablast formation. However, although BCR crosslinking could not by itself promote GC B cell selection or differentiation, it could synergize with T cell help to enhance the GC and plasmablast responses when T cell help was limiting. These findings indicate that GC B cells can integrate variable inputs from T cell help and BCR signaling in vivo for an optimal process of selection and differentiation, critical for potent long-term humoral immunity.

SUBMITTER: Turner JS

PROVIDER: S-EPMC6289055 | biostudies-literature | 2018 Nov

REPOSITORIES: biostudies-literature

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B Cell Receptor Crosslinking Augments Germinal Center B Cell Selection when T Cell Help Is Limiting.

Turner Jackson Steed JS Ke Fang F Grigorova Irina Leonidovna IL

Cell reports 20181101 6

Antigen-dependent engagement of germinal center (GC) B cell receptors (BCRs) promotes antigen internalization and presentation for follicular helper T cells. However, whether BCR signaling is critical or synergistic with T cell help for GC B cell selection or differentiation is unclear. Here, by adapting an experimental approach that enables independent delivery of BCR-crosslinking antigen or T cell help to GC B cells in vivo, we showed that T cell help was sufficient to induce GC B cell expansi ...[more]

PMID: 30403996

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