五月女 靖（Transkaryotic Therapies, Inc., Cambridge, MA）
The application of somatic cell gene therapy to large patient populations will require the development of safe and practical approaches to the generation and characterization of genetically manipulated cells. Transkaryotic implantation is a gene-therapy system based on the production of clonal strains of engineered primary and secondary cells, using non-viral methods. Upon implantation, these clonal cell strains stably and reproducibly deliver pharmacologic quantities of protein for the lifetime of the experimental animals. Improvements in this system are now possible by the use of homologous recombination. This will provide a greater degree of control and enhanced flexibility to the genetic modification of patient's cells.