Controlled release delivery vehicles for water-soluble osteogenic proteins from demineralized bovine bone matrix were constructed using polyanhydride polymers. The water-soluble proteins were isolated from a 4 M guanidine hydrochloride extract of bone matrix. The water-soluble proteins possessed Chondrogenic Stimulating Activity (CSA) when tested in stage 24 chick limb bud cell cultures, but were incapable of inducing cartilage or bone in vivo when implanted intramuscularly into mice by themselves. The polyanhydride polymers alone were also incapable of inducing ectopic cartilage or bone. However, when the water-soluble proteins were incorporated into the polymeric delivery vehicle, the combination was capable of inducing cartilage and bone up to 50% of the time. These results demonstrate that it is possible to use polyanhydride polymers as controlled-release delivery vehicles for soluble bioactive factors that interact with a local cell population.

No abstract

A controlled-release delivery vehicle for water-soluble osteogenic proteins from demineralized bone matrix was constructed using purified type I collagen. The water-soluble proteins were isolated from a 4 M GdnHCl extract of bone matrix. Although the water-soluble proteins were capable of inducing cartilage formation in vitro, they were incapable of inducing cartilage or bone in vivo when implanted intramuscularly into mice in the absence of an appropriate delivery vehicle. The collagen-based delivery vehicle alone was also incapable of inducing osteogenesis in vivo. However, when the water-soluble proteins were incorporated into the delivery vehicle, the combination was capable of inducing cartilage and bone 76% of the time. These results demonstrate that it is possible to formulate a controlled-release delivery vehicles for soluble bioactive factors which upon release interact with local responsive cells.

No abstract

No abstract