Monday, February 16, 2015

Light sensitive proteins could one day help mend our broken hearts

Nottingham University. UK: Around 175,000 heart attacks are diagnosed in the UK each year. They can leave irreparable damage to the heart tissue. Stem cell therapy could one day improve our chances of mending a broken heart but getting grafted tissue to beat in sync with the rest of the heart is a major stumbling block in heart tissue engineering.


Scientists at The University of Nottingham and the Israel Institute of Technology aim to overcome this problem using proteins known as rhodopsins which are extremely sensitive to light.

In Nottingham the research, funded by the British Heart Foundation (BHF) and the British Council’s BIRAX initiative (1) is being led by Chris Denning, Professor of Stem Cell Biology in the School of Medicine. He said: “We plan to incorporate this new technology into beating heart muscle patches that can eventually be grafted onto damaged hearts. These patches of muscle tissue can then be controlled by a pacemaker that emits light.”  
 
Our heart beat is controlled by the brain via pace maker cells which trigger the beating of the whole heart. Stem cell cardiomyocytes – cardiac muscle cells – represent a stage of development similar to that of the foetus – not the adult. These immature foetal cells have not had chance to mature so they beat uncontrollably. 

The cell engineering work to make cardiomyocytes that respond to light will be carried out at Nottingham using special robotic platforms. The aim is to make them in sufficient quantities for the team in Israel led by Professor Lior Gepstein to pulse these cells and monitor them with light and carry out transplantation studies in animal models of heart failure.

The heart muscle cells will contain two types of rhodopsin – one which is stimulated by blue light to induce electrical activity and one stimulated by yellow light to suppress electrical activity. This approach ensures that any light-emitting pacemaker will only work on the transplanted tissue containing the rhodopsins.

The researcher team hopes this light sensitive tissue can then be grafted on to a damaged heart, helping it beat more effectively to reduce the devastating effects of heart failure without the risk of heart rhythm problems.

Before the BIRAX scheme, collaboration between UK and Israel scientists had proved difficult despite the world class regenerative research happening in both countries. Professor Denning and Professor Gepstein had previously been competitors in this field but this project will allow them to combine expertise and resources to accelerate developments in regenerative treatments for heart patients.

Professor Denning said: “This grant of £400,000 ensures we can work on a very promising technique for solving one of the major challenges in regenerative medicine to mend a broken heart.

“For years Professor Gepstein and I have been competing to be the first in our field. But this project means that instead of each team doing the same things twice, we will be coordinating our efforts to ensure we can help heart patients as soon as possible.”

Professor Peter Weissberg, Medical Director at the BHF, said: “Science is not an isolated enterprise. It is a global endeavour. While competition between labs can fuel progress, it is nowhere near as productive as bringing the world’s best scientists together to work towards a shared goal.

“The BIRAX initiative makes it possible for the BHF to fund top UK scientists, like Professor Denning, to work with their equivalents in Israel and help us reach our goal of finding new treatments for the millions around the world living with heart failure.”

Alan Gemmell, Director of the British Council, said: “This programme combines the best of what Britain and Israel can offer the world.  World-class scientists and world-leading medical research charities are working with us to improve the lives of millions of people.”

BIRAX is a 5-year, £10 million fund investing in cutting-edge science by world-class researchers in labs in Britain and Israel. It is funded by a mix of philanthropists and medical research foundations or charities. It is Britain’s most important bilateral initiative with Israel. Israel and the United Kingdom are both leaders in regenerative medicine and natural partners for research in this ground-breaking field.