Influence of roxithromycin on inflammatory cytokine production from nasal polyp fibroblasts in vitro.

The influence of macrolide antibiotics, roxithromycin (RXM) and josamycin (JM) on inflammatory cytokine production from human nasal polyp fibroblasts (NPFs) was examined using an in vitro cell culture technique. Addition of RXM at a concentration of 10.0 microg/ml to cell cultures suppressed both IL-6 and RANTES (but not IL-8) production in response to stimulation with 25.0 ng/ml tumor necrosis factor (TNF)-alpha. However, JM could not suppress IL-6, IL-8 and RANTES production from NPFs induced by TNF-alpha stimulation in vitro, even when added to cell cultures at a concentration of 20.0 microgram/ml. In the second part of the study, we examined the influence of RXM on cytokine mRNA expression in NPFs. Addition of RXM at a concentration of 10.0 mg/ml to cell cultures caused reduction of the mRNA expressions of both IL-6 and RANTES, which were enhanced by TNF-alpha stimulation in vitro.