Role of autoimmune response in neuropathic pain of disc herniation.

Abstract

Inflammatory responses cause pain associated with disc herniation. Recent studies have showed that autoimmune-mediated inflammation was evoked by herniated discs because nucleus pulposus is among the sequestered antigens that do not provoke immune reaction in normal conditions. Some nucleus pulposus cells, like cells in the ocular anterior chamber, express Fas-ligand on the cell surface, which can cause apoptosis of Fas-positive immune cells, resulting in the inhibition of autoimmune reactions. However, a secondary infiltration of neutrophils can cause inflammation. Our recent studies showed that the pain associated with disc herniation was related to cell-mediated immune responses with both macrophages and natural killer cells. These results suggest that specific ligands or blockers, which inhibit Toll-like receptor-mediated immune responses, may be a new therapeutic tool for pain associated with herniated discs.