Comparative effects of bone morphogenetic proteins and Sox9 overexpression on matrix accumulation by bovine anulus fibrosus cells: implications for anular repair.

Study Design: An in vitro biologic study comparing the effects of a series of bone morphogenetic proteins (BMPs) and Sox9 on the extracellular matrix accumulation by bovine anulus fibrosus (AF) cells.

Objective: To compare the effects of adenoviral-mediated overexpression of various BMPs and Sox9 on extracellular matrix accumulation by AF cells in vitro.

Summary Of Background Data: Repair of the disrupted AF, which is perceived to be a potential therapy to diminish nucleus pulposus (NP) herniation, may also offer a treatment strategy for severe symptomatic degenerative disc disease.

Transduced bovine articular chondrocytes affect the metabolism of cocultured nucleus pulposus cells in vitro: implications for chondrocyte transplantation into the intervertebral disc.

Study Design: Biologic study on the effects of coculture of bovine articular chondrocytes transduced ex vivo with genes expressing bone morphogenetic proteins (BMPs) on nucleus pulposus (NP) cells.

Objective: To evaluate the effects of bovine articular chondrocytes transduced with adenoviruses expressing various BMPs on proteoglycan and collagen production, and cellular proliferation of NP cells in vitro.

Summary Of Background Data: Matrix synthesis by intervertebral disc cells is promoted by exposing the cells to growth factors or delivering genes that permit sustained expression of growth factors.

Age-related differences in the accumulation and size of hyaluronan in alginate culture.

The alginate bead culture system has unique properties that make it possible to study the accumulation and turnover of macromolecules in two distinct matrix compartments of the cartilage matrix: the cell-associated matrix (CM) and the further removed matrix (FRM). Taking advantage of this culture system, the purpose of this study was to examine age-related changes in the metabolism of hyaluronan (HA) in these two compartments. Bovine chondrocytes, isolated from fetal, young adult, and old adult articular cartilage, were cultured in alginate beads.