Bioactive FGF-2 in sterilized extracellular matrix

Retention of growth factor activity during disinfection, lyophilization, and sterilization may be key to the development of safe, yet effective, human clinical products derived from biological sources. Traditional methods to reduce the antigenicity of biological materials used for wound healing are thought to destroy the bioactivity of growth factors contained within naturally occurring extracellular matrices. A sterilized extracellular matrix wound dressing (sECM) was examined for bioactive FGF-2 using a sandwich ELISA and an in-vitro bioassay. FGF-2 was present in sECM at a concentration as great as 97.9 +/- 11.7 ng/g. To detect bioactivity, the cell culture medium was incubated with sECM (sECM-CM) and was used as the growth medium for rat pheochromocytoma (PC12) cells. After 48 hours, sECM-CM induced differentiation in 22 percent of the cells versus eight percent of the positive controls. Addition of an FGF-2 neutralizing antibody reduced PC12 differentiation in the sECM-CM-treated cells to nine percent versus one percent in the control wells. These results indicate that both the presence and the bioactivity of FGF-2 are retained in sECM. Because FGF-2 is an important regulator of angiogenesis, wound healing, and regeneration, it is likely that bioactive FGF-2 retained in sECM contributes to the clinical successes observed when this material is used to treat hard-to-heal wounds.