Abstract
Monocytes (Mø) were simultaneously preincubated with Salicylazosulfapyridine (Salazopyrin®;) (SAZ), 0.78–12.5 mM, and lipopolysaccharide from E. coli, 1 × 10−9 g/ml. Presence of SAZ resulted in a dose-dependent decrease in the co-stimulatory activity in Mø culture supernatants, corresponding to a 50% reduction by SAZ, 2.0 mM. Co-stimulatory activity was estimated by the mitogen-induced thymocyte proliferation assay (THY assay). The results indicate an inhibitory effect of SAZ in vitro on the production of IL-1 and other possible co-stimulatory factors. This inhibitory effect was not due to decreased Mø viability, production of suppressive substances, or to drug interference with the THY assay. Equimolar preincubations with sulfapyridine, 5-aminosalicylic acid and N-acety-1–5-aminosalicylic acid were without effect on the production of co-stimulatory factors.