IFN-beta 1b augments glucocorticoid-induced suppression of tumor necrosis factor-alpha production by increasing the number of glucocorticoid receptors on a human monocytic cell line

We studied the effect of recombinant interferon-beta 1b (IFN-beta 1b) on th e sensitivity to glucocorticoids (GC) and on the number of GC receptors (GC R) in the human monocytic cell line THP-1. We found that IFN-beta 1b augmen ts the suppressive effect that dexamethasone has on the stimulated producti on of tumor necrosis factor-alpha (TNF-alpha), most likely related to the i ncreased number of GCR observed after exposure to IFN-beta 1b. This provide s a possible clue to the mechanism of action of IFN-beta in multiple sclero sis.