Transcription factor NF-kappa B regulates inducible CD83 gene expression in activated T lymphocytes

The immunoglobulin superfamily member CD83 is expressed on the surface of m ature dendritic cells that present processed antigens to T lymphocytes. In addition, T cells acquire CD83 expression following mitogenic stimulation i n vitro. Here we report two lines of evidence demonstrating that this induc ible lymphocyte response is genetically programmed by transcription factor NF-kappaB and contingent upon proteolytic breakdown of its cytoplasmic inhi bitor I kappaB alpha. First, signal-dependent induction of CD83 mRNA expres sion is blocked in both transformed and primary T cells harboring a degrada tion-resistant mutant of I kappaB alpha that constitutively represses NF-ka ppaB. Second, as revealed in gel retardation assays, the I kappaB alpha con stitutive repressor prevents the inducible interaction of NF-kappaB with co nsensus recognition sites identified in the CD83 promoter. Given that I kap paB alpha is functionally coupled to the T-cell antigen receptor, these fin dings suggest that the downstream transcription unit for CD83 is triggered by NF-kappaB during an adaptive immune response. (C) 2001 Elsevier Science Ltd. All rights reserved.