Expression of low-molecular-weight kininogen mRNA in human fibroblast WI38 cells

Expression of the low-molecular-weight kininogen (L-kininogen) mRNA in the human fibroblast cell line WI38 was examined by means of the reverse-transcription polymerase chain reaction and Southern blotting using human L-kininogen cDNA as a probe. The results demonstrated that WI38 fibroblasts expressed L-kininogen mRNA and that the expression was stimulated by 1 mM dibutyryl cAMP or 10 microM prostaglandin E2. Dexamethasone (1 microM) inhibited the stimulatory effect of prostaglandin E2. These results suggest that human fibroblasts supply L-kininogen, a protein precursor of the inflammatory mediator kinins, to connective tissues in response to inflammatory stimuli and that glucocorticoids may exert the antiinflammatory effect in part by inhibiting the local production of L-kininogen.