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The microanatomic segregation of selection by apoptosis in the germinal center.

ABSTRACT: B cells undergo rapid cell division and affinity maturation in anatomically distinct sites in lymphoid organs called germinal centers (GCs). Homeostasis is maintained in part by B cell apoptosis. However, the precise contribution of apoptosis to GC biology and selection is not well defined. We developed apoptosis-indicator mice and used them to visualize, purify, and characterize dying GC B cells. Apoptosis is prevalent in the GC, with up to half of all GC B cells dying every 6 hours. Moreover, programmed cell death is differentially regulated in the light zone and the dark zone: Light-zone B cells die by default if they are not positively selected, whereas dark-zone cells die when their antigen receptors are damaged by activation-induced cytidine deaminase.

SUBMITTER: Mayer CT

PROVIDER: S-EPMC5957278 | biostudies-literature | 2017 Oct

REPOSITORIES: biostudies-literature

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The microanatomic segregation of selection by apoptosis in the germinal center.

Mayer Christian T CT Gazumyan Anna A Kara Ervin E EE Gitlin Alexander D AD Golijanin Jovana J Viant Charlotte C Pai Joy J Oliveira Thiago Y TY Wang Qiao Q Escolano Amelia A Medina-Ramirez Max M Sanders Rogier W RW Nussenzweig Michel C MC

Science (New York, N.Y.) 20170921 6360

B cells undergo rapid cell division and affinity maturation in anatomically distinct sites in lymphoid organs called germinal centers (GCs). Homeostasis is maintained in part by B cell apoptosis. However, the precise contribution of apoptosis to GC biology and selection is not well defined. We developed apoptosis-indicator mice and used them to visualize, purify, and characterize dying GC B cells. Apoptosis is prevalent in the GC, with up to half of all GC B cells dying every 6 hours. Moreover, ...[more]

PMID: 28935768

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YY1 Regulates the Germinal Center Reaction by Inhibiting Apoptosis.

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