OBJECTIVETo observe the morphology and phenotypes of cells extracted from the endplate in the intervertebral discs and identify the factors affecting their biological characteristic.

METHODSThe intervertebral disc endplate were digested enzymatically, and the morphology of the obtained cells was examined under light microscope. Immunhistochemical analysis of collagen II and real-time PCR was carried out, and the morphologies, viability, cell growth, apoptosis and chondrocyte matrix production were compared between the cells isolated from the degenerative and normal vertebral endplates.

RESULTSThe cells in primary culture presented with spherical and oval morphology, and the cytoplasm was stained blue with toluidine blue. The morphologies of the cartilage endplate cells and the articular cells were almost identical. All the freshly isolated cells expressed collagen II. The degenerative vertebral endplate cells showed decreased expression of collagen II with increased apoptotic cells as compared with normal vertebral endplate cells.

CONCLUSIONThe intervertebral disc endplate cells, like articular cartilage cells, express cartilage-specific matrix proteins. Degenerative vertebral endplate cells show decreased cell vitality with increases cell apoptosis.