First-class delivery: Getting growth factors to their destination

Growth factor bioavailability in therapeutic applications such as wound healing is limited by extracellular matrix sequestration, proteolysis, and clearance. Local, transient delivery by gene transfer is an attractive concept. Many transfection strategies are available, and adenoviral vectors are in clinical trials. Keratinocyte growth factor-1 (KGF-1), an epithelial-specific member of the fibroblast growth factor (FGF) family, has achieved limited success in protein formulations. Matrix-and cell-based strategies for delivering a KGF-1 virion to target tissue may improve the reproducibility and efficiency of the process, although the advantages of cell-based therapy must be weighed against its added cost and complexity.