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

Vinod Krishna; Kurtis E Bachman

doi:10.1101/061879

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bioRxiv · 10.1101/061879

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

Vinod Krishna·Kurtis E Bachman

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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.

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Vinod Krishna, Kurtis E Bachman. 2016-07-05. A mechanism of T cell dependent selection of antigen engaged Germinal Center B cells. https://doi.org/10.1101/061879

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