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A mechanism of T cell dependent selection of antigen engaged Germinal Center B cells.

ABSTRACT: A model of B cell affinity selection is proposed, and an explanation of peripheral tolerance mechanisms through antibody repertoire editing is presented. We show that affinity discrimination between B cells is driven by a competition between obtaining T cell help and removal of B cells from the light zone, either through apoptosis or by a return to the dark zone of germinal centers. We demonstrate that this mechanism also allows for the negative selection of self reactive B cells and maintenance of B cell tolerance during the Germinal Center reaction. Finally, we demonstrate that clonal expansion upon return to the Germinal Center dark zone amplifies differences in the antigen affinity of B cells that survive the light zone.

SUBMITTER: Krishna V

PROVIDER: S-EPMC6107130 | biostudies-literature | 2018

REPOSITORIES: biostudies-literature

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A mechanism of T cell dependent selection of antigen engaged Germinal Center B cells.

Krishna Vinod V Krishna Vinod V Bachman Kurtis E KE

PloS one 20180823 8

A model of B cell affinity selection is proposed, and an explanation of peripheral tolerance mechanisms through antibody repertoire editing is presented. We show that affinity discrimination between B cells is driven by a competition between obtaining T cell help and removal of B cells from the light zone, either through apoptosis or by a return to the dark zone of germinal centers. We demonstrate that this mechanism also allows for the negative selection of self reactive B cells and maintenance ...[more]

PMID: 30138347

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