Related Experiment Video
Updated: Jul 17, 2026

A Proinflammatory, Degenerative Organ Culture Model to Simulate Early-Stage Intervertebral Disc Disease.
Published on: February 14, 2021
Galectin-3 expression in the intervertebral disc: a useful marker of the notochord phenotype?
Erbil Oguz1, Tsung-Ting Tsai, Alberto Di Martino
1Department of Orthopaedic Surgery, Thomas Jefferson University, Philadelphia, PA 19107, USA.
Study Design:
Galectin-3 expression in rat intervertebral disc at different stages in postnatal life is evaluated.
Objective:
To determine if galectin-3 expression is confined to cells of the nucleus pulposus in the postnatal rat intervertebral disc.
Summary Of Background Data:
During embryonic development, the anulus fibrosus is derived from the sclerotome, whereas the nucleus pulposus is notochordal. Many authorities opine that in the postnatal disc, notochordal cells play a central role in controlling the development of degenerative disc disease. Surprisingly, unequivocal evidence supporting the existence of notochordal cells in the nucleus pulposus in postnatal life has yet to be demonstrated. Since the expression of galectin-3 is commonly used to identify notochordal cells, we evaluated its expression in tissues of the rat disc and in cultured cells.
Methods:
Galectin-3 expression was studied in the nucleus pulposus and anulus fibrosus tissue of rat discs (2 days, 9 weeks, and 10 months old), and cultured cells using different biochemical and molecular biology methods. Rat sternal cartilage and cultured sternal chondrocytes were used as controls.
Results:
Immunohistochemical studies indicated that galectin-3 was present in the nucleus pulposus and anulus fibrosus. In both discal tissues and cultured cells, studies confirmed that there was a robust expression of galectin-3 messenger ribonucleic acid and protein. Protein expression patterns were similar in neonatal, young, and mature rats. There was also evidence of intracellular and membrane expression of galectin-3 in the cultured disc cells. Finally, significant levels of galectin-3 were evident in rat sternal cartilage and cultured sternal chondrocytes.
Conclusions:
Results of the study indicate that galectin-3 is expressed in the neonatal, young, and mature rat disc, and its expression is not restricted to the cells of the nucleus pulposus. Because of its ubiquitous expression, this protein cannot be used as a marker of notochordal cells in the postnatal rat disc.
Related Concept Videos
Degenerative Disc Disease ll: Pathophysiology
Degenerative Disc Disease I: Introduction
Role Of Notch Signalling In Intestinal Stem Cell Renewal
Direct cell-to-cell contact is needed for the activation of Notch signaling. The signal is initiated when a notch ligand binds to a receptor on an adjacent cell, also...

