33.2 Various vectors used for gene therapy of hemophilia

Adeno-associated virus (AAV) is the most used virus vector for the clinical trials conducted for hemophilia. This virus is of small size, well known and characterized for its effective gene therapy application. Retroviruses have also been used. Non-viral vectors are also being explored as an alternative to the AAV.

 

The schematic representation below shows the simplified method of gene therapy strategy being used for the treatment of hemophilia. Here the gene encoding for Factor VIII is inserted inside the viral vector and the human cell is infected with this virus. The gene enters the cell, reaches the nucleus and integrates at specific site. The gene is transcribed inside the cell and the functional factor VIII protein is synthesized which effectively elevates or overcomes the limitations of coagulation of the blood.

Figure 33.2 Gene therapy for haemophilia: