Development of a Targeted Gene-Delivery System Using Escherichia coli.

A gene-delivery system based on microbes is useful for development of targeted gene therapy of non-phagocytic cancer cells. Here, the feasibility of the delivery system is illustrated by targeted delivery of a transgene (i.e., eukaryotic GFP) by Escherichia coli to HER2/neu-positive cancer cells. An E. coli strain was engineered with surface display of the anti-HER2/neu affibody. To release the gene cargo, a programmed lysis system based on phage ϕX174 gene E was introduced into the E. coli strain. As a result, 3 % of HER2/neu-positive cells that were infected with engineered E. coli were able to express the GFP.