Most gene therapy protocols using adenovirus vectors currently offer a rather temporary solution to disease. Soon after the gene therapy vector has delivered its therapeutic gene to diseased cells, the gene is often lost or destroyed and the therapeutic benefit is lost. In a paper in the October issue of Nature Biotechnology, researchers at Stanford University School of Medicine have found a way of prolonging a therapeutic gene’s life by getting an adenovirus vector to integrate its genetic cargo into the target cells’ chromosomes. They accomplished this by hooking up their therapeutic gene to a piece of DNA (called a transposon) that naturally integrates into host chromosomes. By inserting the therapeutic gene into the host cell chromosome, they were able to achieve long-term gene expression.
To demonstrate their approach, Mark Kay and colleagues incorporated a transposon containing the sequence for human coagulation Factor IX (hFIX) into one adenoviral vector and the enzymes necessary for cutting and pasting the transposon into another vector. Systematic delivery of the viruses allowed stable integration of the transgene into mouse liver. Integration of the transgene was sufficient to maintain therapeutic levels of hFIX for more than six months in mice. Since integrated transgenes should persist for extended periods of time, these vectors may provide a new means to improve gene therapy.
Mark A. Kay
Stanford University Medical Center
Stanford, CA, USA
Tel: +1 650 498 6531
Abstract available online.
(C) Nature Biotechnology press release.
Message posted by: Trevor M. D'Souza