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Igkappa allelic inclusion is a consequence of receptor editing.

ABSTRACT: The discovery of lymphocytes bearing two light chains in mice carrying self-reactive antibody transgenes has challenged the "one lymphocyte-one antibody" rule. However, the extent and nature of allelically included cells in normal mice is unknown. We show that 10% of mature B cells coexpress both Igkappa alleles. These cells are not the result of failure in allelic exclusion per se, but arise through receptor editing. We find that under physiological conditions, editing occurs both by deletion and by inclusion with equal probability. In addition, we demonstrate that B lymphocytes carrying two B-cell receptors are recruited to germinal center reactions, and thus fully participate in humoral immune responses. Our data measure the scope of allelic inclusion and provide a mechanism whereby autoreactive B cells might "escape" central tolerance.

SUBMITTER: Casellas R

PROVIDER: S-EPMC2118438 | biostudies-literature | 2007 Jan

REPOSITORIES: biostudies-literature

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Igkappa allelic inclusion is a consequence of receptor editing.

Casellas Rafael R Zhang Qingzhao Q Zheng Nai-Ying NY Mathias Melissa D MD Smith Kenneth K Wilson Patrick C PC

The Journal of experimental medicine 20070108 1

The discovery of lymphocytes bearing two light chains in mice carrying self-reactive antibody transgenes has challenged the "one lymphocyte-one antibody" rule. However, the extent and nature of allelically included cells in normal mice is unknown. We show that 10% of mature B cells coexpress both Igkappa alleles. These cells are not the result of failure in allelic exclusion per se, but arise through receptor editing. We find that under physiological conditions, editing occurs both by deletion a ...[more]

PMID: 17210730

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Igkappa allelic inclusion is a consequence of receptor editing.

Publications

Igkappa allelic inclusion is a consequence of receptor editing.

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