Interleukin-1 activates transcription factor NF kappa B in glial cells

Recombinant human interleukin-1 (IL-1) alpha and beta were found to activate a latent cytosolic form of the transcription factor NF kappa B in rat C6 glioma. IL-1 beta was 10 times more potent than IL-1 alpha for this activity and both were inhibited by the IL-1 receptor antagonist. The activation was detectable from 20 min and remained sustained for up to 24 h. The electrophoretic mobility of the activated complex was shown to be different from that of the corresponding complexes in another IL-1-responsive cell line, the murine thymoma line EL4.NOB-1. C6 cells, when transiently transfected with five NF kappa B consensus sequence repeats linked to the reporter gene chloramphenicol acetyltransferase (CAT), demonstrated increased CAT activity in response to IL-1 beta treatment. The activation of NF kappa B in glial cells may thus represent an early step in IL-1 signalling in brain and is likely to have consequences for IL-1-induced gene expression in these cells.