Differential expression of Rel/NF-kappa B and octamer factors is a hallmark of the generation and maturation of dendritic cells

A key feature of maturation of dendritic cells is the down-regulation of an tigen-processing and up-regulation of immunostimulatory capacities. To stud y the differential expression of transcription factors in this process, we investigated the nuclear translocation and DNA binding of Rel/NF-kappa B an d octamer factors during in vitro generation and maturation of dendritic ce lls compared with macrophage development. RelB was the only factor strongly up-regulated during the generation of both immature dendritic cells and ma crophages. Cytokine-induced maturation of dendritic cells resulted in an in crease in nuclear RelB, p50, p52, and especially c-Rel, whereas cytokine-tr eated macrophages responded poorly. This upregulation of NF-kappa B factors did not correlate with lower levels of cytosolic NF-kappa B inhibitors, th e I kappa Bs, One I kappa B, Bcl-3, was strongly expressed only in mature d endritic cells. Furthermore, generation and maturation of dendritic cells l ed to a continuous down-regulation of the octamer factor Oct-2, whereas mon ocytes and macrophages displayed high Oct-2 levels. A similar pattern of ma turation-induced changes in transcription factor levels was found in cultur ed murine epidermal Langerhans cells, suggesting a general physiological si gnificance of these findings. Finally, this pattern of differential activat ion of Rel and octamer factors appears to be suitable in determining the ma turation stage of dendritic cells generated by treatment with different cyt okine combinations in vitro. (C) 2000 by The American Society of Hematology .