Polymer Encapsulated Xenogeneic Cell Lines: A Novel Approach for Gene Therapy

Abstract

In ex-vivo gene therapy, a gene product can be delivered through the transplantation of autologous cells genetically engineered to express the desired gene. The encapsulation technology which consists in surrounding cells by a semipermeable polymeric membrane allows cells from either an allogeneic or xenogeneic source to be transplanted across species. This technology offers interesting potential for gene therapy such as the use of cell lines. Cell lines offer several advantages including unlimited availability, the possibility of rapid in vitro screening for the presence of pathogens from which cell bank are established, and the suitability for stable gene transfer using non-viral based recombinant DNA techniques. Use of a cell line of xenogeneic origin provides an additional advantage since the transplanted cells will be rejected by the host immune system in the event of device breakage. To increase the safety level, the engineered cells also express a suicide gene (thymidine kinase) rendering the cells sensitive to gancyclovir mediated destruction.