The Greffex Platform
Genetic approaches will fundamentally change the future of medicine. Information derived from the Human Genome Project will allow the development of novel therapeutic approaches whose implementations will hinge on the availability of an optimized gene delivery system. Numerous different gene transfer system have been investigated many of which were built on different naturally occurring viruses.
Greffex recognized that engineered adenoviruses could form the ideal vehicle to deliver genetic material. They would be safe, stable and “clean”. Earlier iterations of such vectors carried numerous viral genes required for efficient production. These genes had the ability to alter normal cellular behavior and to attract vigorous immune responses. To remove all viral genes and thus prevent their interference, helper viruses originally had to be employed to allow packaging of the therapeutic vector. However contamination of these fully deleted helper dependent adenoviral vectors hamper their introduction into the clinic.
To address FDA concerns, Greffex has designed a novel adenoviral architecture that allows the manufacture of fully deleted vectors without the use of a helper virus. With the development of this Greffex Vector Platform, we overcame two obstacles: interference by viral genes and contamination by helper viruses.
We have been using our flexible vector to investigate and develop the production of vaccines, gene therapy vectors and specific immune suppression products.
The vaccine platform packages vaccine genomes into capsids of the adenovirus 6 human serotype of low prevalence.
Greffex has previously looked at approaches to allow specific inhibition of immune functions for treatments of autoimmune issues and transplant therapy. The origins of our immune suppression technology can be traced to the observation that under certain conditions, T cells can be guided to destroy themselves instead of antagonizing tissue.
Our engineered veto© technology uses an engineered vector to deliver the immune inhibitory CD8™ gene to different transplants. The major advantage of this approach is its ability selectively to inhibit recipients’ immune responses once the tissue has been transplanted. In contrast to present general immune suppression therapies presently used to protect a transplant, normal protective immunity is maintained and recipients are not threatened by infectious diseases.
We have been adapting engineered veto© to “conventional” gene therapy specifically to prevent the immune system from interfering with the therapeutic effect.