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RelB nuclear translocation regulates B cell MHC molecule, CD40 expression, and antigen-presenting cell function.

ABSTRACT: Mice with targeted RelB mutations demonstrated an essential role for RelB in immune responses and in myeloid dendritic cell differentiation. Human studies suggested a more global transcriptional role in antigen presentation. Burkitt lymphoma cell lines were used as a model to examine the role of RelB in antigen presentation. After transient transfection of BJAB with RelB, strong nuclear expression of RelB-p50 heterodimers was associated with increased APC function and expression of CD40 and MHC class I. Antisense RelB in DG75 reduced antigen-presenting capacity and CD40-mediated up-regulation of MHC molecules. The data indicate that RelB transcriptional activity directly affects antigen presentation and CD40 synthesis. Stimulation of RelB transcriptional activity may provide a positive feedback loop for facilitating productive APC/T cell interactions.

SUBMITTER: O'Sullivan BJ

PROVIDER: S-EPMC17215 | biostudies-literature | 2000 Oct

REPOSITORIES: biostudies-literature

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RelB nuclear translocation regulates B cell MHC molecule, CD40 expression, and antigen-presenting cell function.

O'Sullivan B J BJ MacDonald K P KP Pettit A R AR Thomas R R

Proceedings of the National Academy of Sciences of the United States of America 20001001 21

Mice with targeted RelB mutations demonstrated an essential role for RelB in immune responses and in myeloid dendritic cell differentiation. Human studies suggested a more global transcriptional role in antigen presentation. Burkitt lymphoma cell lines were used as a model to examine the role of RelB in antigen presentation. After transient transfection of BJAB with RelB, strong nuclear expression of RelB-p50 heterodimers was associated with increased APC function and expression of CD40 and MHC ...[more]

PMID: 11027342

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