The influence of Matrigel or growth factor reduced Matrigel on human intervertebral disc cell growth and proliferation.

Matrigel (reconstituted basement membrane extract) is a potent inducer of cell growth and differentiation in vitro. This study examined phenotypic variation and proliferative responses of human annular intervertebral disc cells in vitro in Matrigel and Growth Factor Reduced Matrigel (GFR-Matrigel). Cells from age- and gender-matched control subjects and patients with degenerative disc disease were grown either on the surface of, or suspended within, either matrices. Disc cells grew well on top of both matrices with cells spontaneously forming cell projections. Cells grown within either matrix migrated within the gel to form colonies. Increased colony formation within the matrices was seen with young control and patient cells (p < 0.05). Old and young control and patient cells showed increased proliferation within GFR-Matrigel compared to Matrigel. When grown on the matrix surface, young patient and control donor cells showed increased proliferation on GFR-Matrigel compared to Matrigel. Cellular proliferation was significantly greater inside a 3-dimensional environment than a two-dimensional surface monolayer environment. Disc cells had increased proliferation when grown in or on GFR-Matrigel compared to Matrigel. These studies serve as a baseline for subsequent investigations regarding effects of cytokines on disc cells and increase our knowledge of the influence of extracellular matrices on disc cell proliferation.