Expression of chondrocyte markers by cells of normal and degenerate intervertebral discs.

Aims: To investigate the phenotype of cells in normal and degenerate intervertebral discs by studying the expression of molecules characteristic of chondrocytes in situ.

Methods: Human intervertebral discs taken at surgery were graded histologically, and classified on this basis as normal or degenerate. Eighteen of each type were selected, and in situ hybridisation was performed for the chondrocytic markers Sox9 and collagen II using (35)S labelled cDNA probes.