Medications often target a particular type of molecule known as receptors. Receptors act like docking stations on cells and help deliver a chemical message to a cell. By “docking” with this receptor the therapy exerts its effect by either mimicking, or blocking the action of the natural chemical messenger that would normally dock on the receptor. However, many drug molecules often bind to other similar receptors resulting in side effects and in some cases toxicity.
A key goal of modern drug development is to design medications that are very specific for their target, and minimise any incidental effects. In an attempt to make drugs as targeted as possible for their intended receptor, one of the most promising approaches is the use of specialised gene delivery methods to ensure the drug molecule is delivered directly to its target.
Dr Veedu’s project aims to develop a chemically-modified DNA enzyme to prevent the ITGA-4 gene from making its product. The aim is to deliver the molecule directly to the T-cells of the immune system in order to directly target the inflammatory cells in MS. This unique approach may offer a safer avenue for more targeted delivery of therapies for the treatment of MS.
Part of Dr Veedu’s results have recently been published in the highly prestigious journal Scientific Reports. In this paper Dr Veedu details how this incubator grant allowed his team to learn the necessary techniques and develop a gene-technology tool called a DNAzyme to target and block the receptor ITGA4.
ITGA4 is used by immune cells to enter the brain and spinal cord. The MS drug Tysabri (Natalizumab), also targets this molecule and has been shown to significantly reduce the number of MS relapses. Dr Veedu’s approach to blocking this molecule aims to produce this same effect, but also to reduce the risks associated with Tysabri treatment.
To complete this work, Dr Veedu and his team established a screening method to determine the efficiency and stability of the many different DNAzymes they produced. They also developed a more efficient and stable way of producing this specific DNAzyme, which is important if the molecule is to be efficient and practical for clinical use.
In further experiments Dr Veedu also began developing a way for this DNAzyme to be delivered to specific immune cells called T cells. T cells are important in the development of MS as they are involved in attacking the myelin sheath surround the nerve cells and causing inflammation in the brain. It is the T-cells that use the ITGA4 molecule to help them enter the brain to cause the inflammation.
This exciting gene technology approach to targeting the immune system is at the frontier of next generation of medicines. This preliminary work could lead to an innovative, targeted MS therapeutics that can control only the ‘bad’ effects of the immune system, but leave the ‘helpful’ parts untouched, potentially greatly reducing the risks associated with some medications.
Updated: 8 August 2017
Updated: 03 January, 2016