Project description:Gold salts has been used in the treatment of rheumatoid arthritis but has been replaced by biologicals such as TNF-alpha inhibitors. The mechanisms behind the anti-inflammatory effect of metallic gold ions are still unknown, however, recent data showed that charged gold atoms are released from pure metallic gold implants by macrophages via a dissolucytosis membrane, and that gold ions are taken up by local macrophages, mast cells and to some extent fibroblasts. These current findings offer new treatment options for metallic gold and deeper understanding of the effect of metallic gold on key inflammatory cells as macrophages are essential. In the present study the impact of phagocytised gold ions on the global gene expression profile of the human monocytic cell line THP-1 was investigated, using microarray analysis comprising approximately 20,000 genes. The gene expression data was confirmed by measurement of three secreted proteins. A unique gene expression signature of dissolucytotic macrophages that had taken up gold ions was demonstrated. A large number of regulated genes were functionally related to immunomodulation/protection. Gold ion uptake into macrophages induced downregulation of central inflammatory cytokines as TNF-alpha, IL-32 and CD28. The data obtained in this study offer new insights into the mode of action of gold ions and suggest a future role of metallic gold as implants or topical applications in treating inflammation.
