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T cell-B cell thymic cross-talk: maintenance and function of thymic B cells requires cognate CD40-CD40 ligand interaction.

ABSTRACT: Thymic development requires bidirectional interaction or cross-talk between developing T cells and thymic stromal cells, a relationship that has been best characterized for the interaction between thymocytes and thymic epithelial cells. We have characterized in this article the requirement for similar cross-talk in the maintenance and function of thymic B cells, another population that plays a role in selection of developing thymic T cells. We found that maintenance of thymic B cells is strongly dependent on the presence of mature single-positive thymocytes and on the interactions of these T cells with specific Ag ligand. Maintenance of thymic B cell number is strongly dependent on B cell-autonomous expression of CD40, but not MHC class II, indicating that direct engagement of CD40 on thymic B cells is necessary to support their maintenance and proliferation. Thymic B cells can mediate negative selection of superantigen-specific, self-reactive, single-positive thymocytes, and we show that CD40 expression on B cells is critical for this negative selection. Cross-talk with thymic T cells is thus required to support the thymic B cell population through a pathway that requires cell-autonomous expression of CD40, and that reciprocally functions in negative selection of autoreactive T cells.

SUBMITTER: Fujihara C

PROVIDER: S-EPMC4239311 | biostudies-literature | 2014 Dec

REPOSITORIES: biostudies-literature

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T cell-B cell thymic cross-talk: maintenance and function of thymic B cells requires cognate CD40-CD40 ligand interaction.

Fujihara Chiharu C Williams Joy A JA Watanabe Masashi M Jeon Hyein H Sharrow Susan O SO Hodes Richard J RJ

Journal of immunology (Baltimore, Md. : 1950) 20141024 11

Thymic development requires bidirectional interaction or cross-talk between developing T cells and thymic stromal cells, a relationship that has been best characterized for the interaction between thymocytes and thymic epithelial cells. We have characterized in this article the requirement for similar cross-talk in the maintenance and function of thymic B cells, another population that plays a role in selection of developing thymic T cells. We found that maintenance of thymic B cells is strongly ...[more]

PMID: 25344473

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Dataset Information

T cell-B cell thymic cross-talk: maintenance and function of thymic B cells requires cognate CD40-CD40 ligand interaction.

Publications

T cell-B cell thymic cross-talk: maintenance and function of thymic B cells requires cognate CD40-CD40 ligand interaction.

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