Adenosine and ATP affect LPS-induced cytokine production by macrophages

Macrophages are essential for controlling the majority of infections, and are mediators of natural immunity. During infection, lipopolysaccharide (LPS) stimulates macrophages to produce pro-inflammatory cytokines. Adenosine and ATP released into the extracellular space by immunological stimuli have been shown to regulate various immune functions. We evaluate immunological effects of adenosine and ATP on the production of cytokines related to inflammation and Thl/Th2 balance by rat peritoneal macrophages. Adenosine and ATP respectively increased the production of IL-10 without affecting the production of IL-1 ƒÀand IL-12 by macrophages. In addition, adenosine and ATP prevented the production of IL-1 iS and IL-12 by LPSstimulated macrophages. In contrast, adenosine inhibited IL-10 production by LPSstimulated macrophages, whereas ATP potentiated IL-10 production by LPS-stimulated macrophages. These results suggest that conditions related to increased adenosine and/or ATP may play an important role in .a wide range of immune reactions including the Thl and Th2 immune response.