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Cutting edge: An in vivo reporter reveals active B cell receptor signaling in the germinal center.

ABSTRACT: Long-lasting Ab responses rely on the germinal center (GC), where B cells bearing high-affinity Ag receptors are selected from a randomly mutated pool to populate the memory and plasma cell compartments. Signaling downstream of the BCR is dampened in GC B cells, raising the possibility that Ag presentation and competition for T cell help, rather than Ag-dependent signaling per se, drive these critical selection events. In this study we use an in vivo reporter of BCR signaling, Nur77-eGFP, to demonstrate that although BCR signaling is reduced among GC B cells, a small population of cells exhibiting GC light zone phenotype (site of Ag and follicular helper T cell encounter) express much higher levels of GFP. We show that these cells exhibit somatic hypermutation, gene expression characteristic of signaling and selection, and undergo BCR signaling in vivo.

SUBMITTER: Mueller J

PROVIDER: S-EPMC4369439 | biostudies-literature | 2015 Apr

REPOSITORIES: biostudies-literature

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Cutting edge: An in vivo reporter reveals active B cell receptor signaling in the germinal center.

Mueller James J Matloubian Mehrdad M Zikherman Julie J

Journal of immunology (Baltimore, Md. : 1950) 20150227 7

Long-lasting Ab responses rely on the germinal center (GC), where B cells bearing high-affinity Ag receptors are selected from a randomly mutated pool to populate the memory and plasma cell compartments. Signaling downstream of the BCR is dampened in GC B cells, raising the possibility that Ag presentation and competition for T cell help, rather than Ag-dependent signaling per se, drive these critical selection events. In this study we use an in vivo reporter of BCR signaling, Nur77-eGFP, to dem ...[more]

PMID: 25725108

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