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A B-cell receptor-specific selection step governs immature to mature B cell differentiation.

ABSTRACT: Seventy percent of peripheral immature conventional (B2) B cells fail to develop into mature B cells. The nature of this cell loss has not been characterized; the process that governs which immature B cells develop into long-lived peripheral B cells could be either stochastic or selective. Here, we demonstrate that this step is in fact selective, in that the fate of an immature B cell is highly dependent on its Ig receptor specificity. A significant skewing of the B cell receptor repertoire occurs by the time cells enter the mature B cell fraction, which indicates that there is selection of only a minority of immature B cells to become mature B cells. Because only a few heavy-light chain pairs are enhanced of the diverse available repertoire, we favor the idea that selection is positive for these few heavy-light chain pairs rather than negative against nearly all others. Because most immature B cells are lost at this transition, this putative positive selection event is likely to be a major force shaping the mature B cell receptor repertoire available for adaptive immune responses.

SUBMITTER: Levine MH

PROVIDER: S-EPMC16000 | biostudies-literature | 2000 Mar

REPOSITORIES: biostudies-literature

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A B-cell receptor-specific selection step governs immature to mature B cell differentiation.

Levine M H MH Haberman A M AM Sant'Angelo D B DB Hannum L G LG Cancro M P MP Janeway C A CA Shlomchik M J MJ

Proceedings of the National Academy of Sciences of the United States of America 20000301 6

Seventy percent of peripheral immature conventional (B2) B cells fail to develop into mature B cells. The nature of this cell loss has not been characterized; the process that governs which immature B cells develop into long-lived peripheral B cells could be either stochastic or selective. Here, we demonstrate that this step is in fact selective, in that the fate of an immature B cell is highly dependent on its Ig receptor specificity. A significant skewing of the B cell receptor repertoire occu ...[more]

PMID: 10688906

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A B-cell receptor-specific selection step governs immature to mature B cell differentiation.

Publications

A B-cell receptor-specific selection step governs immature to mature B cell differentiation.

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