INDUCTION OF INTERLEUKIN-6 AND INTERLEUKIN-8 EXPRESSION BY BRONCHO-VAXOM (OM-85 BV) VIA C-FOS SERUM RESPONSIVE ELEMENT/

Background - Broncho-Vaxom (OM-85 BV) increases the resistance of the respiratory tract to bacterial infections by modulating host immune re sponses. The compound increases serum IgG levels but decreases IgE lev els in patients suffering from chronic bronchitis or chronic obstructi ve pulmonary disease. It increases concentrations of gamma-interferon (IFN-gamma), IgA, and interleukin (IL)-2 in bronchoalveolar lavage flu id of patients with bronchitis. Treatment with OM-85 BV increases the number of T helper and natural killer cells. In this study the effects of OM-85 BV on transcription of cytokines is investigated in human lu ng fibroblasts. Methods - Transcription and synthesis of IL-6 and IL-8 were assessed in cultured primary human lung fibroblasts using standa rd methods of Northern blot analysis for the level of mRNAs and enzyme linked immunosorbent assay for proteins. Results - Broncho-Vaxom (OM- 85 BV) at different concentrations induced transcription of IL-6 and I L-8. The effect of the drug on transcription of IL-6 and IL-8 genes co rrelated with secretion of the proteins into cell supernatants. OM-85 BV-dependent expression of the interleukin genes involved C-Fos/serum responsive element (C-Fos/SRE). Conclusions - The data suggest that th e various immunopharmacological activities of OM-85 BV that have been described in clinical studies may be explained by its ability to induc e expression of IL-6 and IL-8.