Haemophilia A is a blood clotting disease due to a genetic lack of production of Factor VIII, a crucial blood-clotting factor. This is called a X-linked recessive disease and the large majority of sufferers are male.
There is no cure for Haemophilia A, and haemophiliacs require regular, expensive transfusions of Factor VIII to survive, failing which even the slightest injury to the body can lead to uncontrolled or even fatal bleeding. Sometimes, antibodies are generated against replacement Factor VIII, so even more complex and expensive therapies are required to overcome this problem. Transfusion itself of contaminated blood has also resulted in transmission of the dreaded HIV (AIDS) virus.
Professor Kon Oi Lian at the National Cancer Centre has successfully implanted the Factor VIII gene into robust Cord Lining Stem Cells which are able to tolerate electroporation to allow for Site Specific Insertion of the Factor VIII gene into its specific locus. Thetransplantation of these cells into mice have maintained levels of Factor VIII for up to 14 days, restoring their blood clotting ability.
This is the first step in research, with the ultimate aim of transplanting these cells into man to provide a long-term replacement of Factor VIII for sufferers of Haemophilia A.
The above work by Professor Kon has been published and not only shows successful integration into Cord Lining Epithelial Cells of the Factor VIII gene into haemophiliac mice and improvement of their clotting characteristics, but also shows the robustness of these cells as inserting the Factor VIII gene would damage weaker cells.
Publication: Sivalingam J, Krishnan S, Ng WH, et al. Biosafety assessment of site-directed transgene integration in human umbilical cord-lining cells. Mol Ther. 2010; (18)7: 1346-1356
This study will be followed by a dog study, after which human trials will follow.