Towards biological anulus repair: TGF-β3, FGF-2 and human serum support matrix formation by human anulus fibrosus cells

• Published in: Tissue & cell Vol. 45; no. 1; pp. 68 - 76
• Main Authors: Hegewald, Aldemar A, Zouhair, Sabra, Endres, Michaela, Cabraja, Mario, Woiciechowsky, Christian, Thomé, Claudius, Kaps, Christian
• Format: Journal Article
• Language: English
• Published: Scotland Elsevier Ltd 01-02-2013
• Subjects: Adult; Advanced Basic Science; Aged; Aged, 80 and over; Anulus fibrosus; Cell Culture Techniques; Cells, Cultured; Extracellular matrix; Extracellular Matrix - drug effects; Extracellular Matrix - metabolism; Extracellular Matrix - pathology; Female; Fibroblast Growth Factor 2 - metabolism; Fibroblast Growth Factor 2 - pharmacology; Growth factors; Humans; Intervertebral disc; Intervertebral Disc - drug effects; Intervertebral Disc - metabolism; Intervertebral Disc - pathology; Intervertebral Disc Degeneration - metabolism; Intervertebral Disc Degeneration - pathology; Intervertebral Disc Displacement - metabolism; Intervertebral Disc Displacement - pathology; Regeneration; Serum - metabolism; Tissue Engineering; Transforming Growth Factor beta3 - metabolism; Transforming Growth Factor beta3 - pharmacology; Anulus fibrosus; Regeneration; Extracellular matrix; Tissue engineering; Growth factors; Intervertebral disc
• ISSN: 0040-8166; 1532-3072
• DOI: 10.1016/j.tice.2012.09.011

Abstract Closure and biological repair of anulus fibrosus (AF) defects in intervertebral disc diseases is a therapeutic challenge. The aim of our study was to evaluate the anabolic properties of bioactive factors on cartilaginous matrix formation by AF cells. Human AF cells were harvested from degenerated lumbar AF tissue and expanded in monolayer culture. AF cell differentiation and matrix formation was initiated by forming pellet cultures and stimulation with hyaluronic acid (HA), human serum (HS), fibroblast growth factor-2 (FGF-2), transforming growth factor-β3 (TGF-β3) and TGF-β3/FGF-2 for up to 4 weeks. Matrix formation was assessed histologically by staining of proteoglycan, type I and type II collagens and by gene expression analysis of typical extracellular matrix molecules and of catabolic matrix metalloproteinases MMP-2 and MMP-13. AF cells, stimulated with HS, FGF-2 and most pronounced with TGF-β3 or TGF-β3/FGF-2 formed a cartilaginous matrix with significantly enhanced expression of matrix molecules and of MMP-13. Stimulation of AF cells with TGF-β3 was accompanied by induction of type X collagen, known to occur in hypertrophic cartilage cells having mineralizing potential. HA did not show any chondro-inductive characteristics. These findings suggest human serum, FGF-2 and TGF-β3 as possible candidates to support biological treatment strategies of AF defects.