Human herniated inter-vertebral discs: No evidence of an immune response

Many previous authors have reported morphological and histochemical observations on the nucleus pulposus in human herniated discs. It has been implied that an autoimmune response may be a cause of tissue damage, or may maintain the process involved in the invertebral disc herniation and consequent back pain. In a preliminary study we have now evaluated the presence of HLA-DR antigens in nucleus pulposus frozen sections and the presence of endothelial cells, by the use of antibodies against the von Willebrand factor. The results, on samples from 11 patients, showed only a few feeble HLA-DR antigen-positive cells in one case and no positivity for the von Willebrand factor. Therefore, on the basis of the results in this study, it may be said that an HLA-DR mediated auto-immune mechanism in human discal herniation is unlikely.