Cell and gene therapy in the treatment of pain

Chronic pain represents a clinical problem of enormous impact. Understanding of the anatomy, pharmacology, and physiology of pain has resulted in the identification of new targets and candidate drugs, but effective novel therapies have been slow to emerge. One approach is to transplant cells that secrete bioactive macromolecules, or use viral vectors to transfer the genes coding for those molecules, in order to deliver short-lived potent peptides of known analgesic efficacy to targeted sites in the nervous system. The data from animal models are reviewed, and the prospect for development of human therapies based on this approach is considered.