This study investigated the correlation between regression of the herniated intervertebral disk and cellular proliferation in the surgical specimens. Tissues of herniated discs were obtained from 24 patients. For immunohistochemical studies, we used antibodies against CD68, UCHL-1, Vimentin, and Tenascin. Strong immunostaining for CD68 or Vimentin was observed in proliferating cells of herniated discs. Moderate immunostaining for Tanascin was detected in the extracellular matrix of the cellular proliferation area. The results presented here suggest that phagocytosis by macrophages and fibrosis by fibroblasts produce regression of herniated discs.
