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Germinal center B cells recognize antigen through a specialized immune synapse architecture.

ABSTRACT: B cell activation is regulated by B cell antigen receptor (BCR) signaling and antigen internalization in immune synapses. Using large-scale imaging across B cell subsets, we found that, in contrast with naive and memory B cells, which gathered antigen toward the synapse center before internalization, germinal center (GC) B cells extracted antigen by a distinct pathway using small peripheral clusters. Both naive and GC B cell synapses required proximal BCR signaling, but GC cells signaled less through the protein kinase C-?-NF-?B pathway and produced stronger tugging forces on the BCR, thereby more stringently regulating antigen binding. Consequently, GC B cells extracted antigen with better affinity discrimination than naive B cells, suggesting that specialized biomechanical patterns in B cell synapses regulate T cell-dependent selection of high-affinity B cells in GCs.

SUBMITTER: Nowosad CR

PROVIDER: S-EPMC4943528 | biostudies-literature | 2016 Jul

REPOSITORIES: biostudies-literature

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Germinal center B cells recognize antigen through a specialized immune synapse architecture.

Nowosad Carla R CR Spillane Katelyn M KM Tolar Pavel P

Nature immunology 20160516 7

B cell activation is regulated by B cell antigen receptor (BCR) signaling and antigen internalization in immune synapses. Using large-scale imaging across B cell subsets, we found that, in contrast with naive and memory B cells, which gathered antigen toward the synapse center before internalization, germinal center (GC) B cells extracted antigen by a distinct pathway using small peripheral clusters. Both naive and GC B cell synapses required proximal BCR signaling, but GC cells signaled less th ...[more]

PMID: 27183103

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