The analgesic potential of cytokine neutralization with biologicals.

Many acute and chronic inflammatory diseases, cancer and neuropathic disorders are accompanied by severe pain states reducing drastically the life quality of the patients. Biologicals which preferentially target cytokines often reduce the disease processes by influencing immune cells, tissue healing, inflammatory aspects and other typical processes of the diseases. Remarkably the effect of biologicals in pain and nociception is often neglected or insufficiently explored. However, because of the dense interaction of the nociceptive system with the surrounding peripheral or central tissue, targeting cytokines has the potential to treat pain at the same time as the other symptoms of the disease. The following review shows mainly results from animal experiments (with some parallels to human studies). It depicts where and how cytokines are involved in nociceptive processing and pain and also indicates possible target strategies. It concentrates on the excitatory cytokines IL-6, TNF-α, IL-1ß, IFN-γ and IL-17.