Intracerebral delivery of growth factors: potential application of genetically modified fibroblasts

To date, a number of different growth factors (e.g. nerve growth factor, brain-derived neurotrophic factor, neurotrophin-3, ciliary neurotrophic factor, and fibroblast growth factor) have been shown to act as a neurotrophic and/or neurotrophic agents on distinct neuronal populations within the peripheral and central nervous system. Knowledge as to how most of these factors influence the development and regeneration of growth factor-sensitive neurons has been obtained from in vitro examination. A new approach that can be used to assess the effects of growth factors on neuronal groups in vivo is the combined use of gene transfer and intracerebral grafting techniques. The present article explores the potential use of grafting genetically modified fibroblasts within the nervous system as a delivery method for growth factors.