Autologous Nucleus Pulposus Attracts Monocytes In Vivo In A Pig Model. Implications For The Pathophysiology Of Sciatica.

Abstract

Previous experimental studies have indicated that that an autoimmune reaction towards herniated nucleus pulposus may constitute a pathogenetic component in the pathophysiology of sciatica. If an autoimmune reaction would be present, one would expect that exposure of nucleus pulposus to the host would induce an up regulation of antigen-presenting cells, such as monocytes. Autologous nucleus pulposus was placed in perforated titanium chambers, which were placed subcutaneously in pigs, together with an equal amount of empty chambers for control. After 7 days, the chambers were harvested and the number of monocytes in the chambers was determined using flow cytometry. The proportion of monocytes was significantly higher in the nucleus pulposus filled chambers than in the empty chambers. In conclusion, nucleus pulposus was shown to attract monocytes, which may suggest that monocytes might play a role in the pathophysiology of sciatica.