A timely article for Valentine’s Day. Researchers continue to make astonishing progress in areas of cell biology and human genomics. So, it should come as no surprise that growing a customized, replacement heart in a lab from reprogrammed cells will one day be on the horizon.

[div class=attrib]From the Guardian:[end-div]

Every two minutes someone in the UK has a heart attack. Every six minutes, someone dies from heart failure. During an attack, the heart remodels itself and dilates around the site of the injury to try to compensate, but these repairs are rarely effective. If the attack does not kill you, heart failure later frequently will.

“No matter what other clinical interventions are available, heart transplantation is the only genuine cure for this,” says Paul Riley, professor of regenerative medicine at Oxford University. “The problem is there is a dearth of heart donors.”

Transplants have their own problems – successful operations require patients to remain on toxic, immune-suppressing drugs for life and their subsequent life expectancies are not usually longer than 20 years.

The solution, emerging from the laboratories of several groups of scientists around the world, is to work out how to rebuild damaged hearts. Their weapons of choice are reprogrammed stem cells.

These researchers have rejected the more traditional path of cell therapy that you may have read about over the past decade of hope around stem cells – the idea that stem cells could be used to create batches of functioning tissue (heart or brain or whatever else) for transplant into the damaged part of the body. Instead, these scientists are trying to understand what the chemical and genetic switches are that turn something into a heart cell or muscle cell. Using that information, they hope to programme cells at will, and help the body make repairs.

It is an exciting time for a technology that no one thought possible a few years ago. In 2007, Shinya Yamanaka showed it was possible to turn adult skin cells into embryonic-like stem cells, called induced pluripotent stem cells (iPSCs), using just a few chemical factors. His technique radically advanced stem cell biology, sweeping aside years of blockages due to the ethical objections about using stem cells from embryos. He won the Nobel prize in physiology or medicine for his work in October. Researchers have taken this a step further – directly turning one mature cell type to another without going through a stem cell phase.

And politicians are taking notice. At the Royal Society in November, in his first major speech on the Treasury’s ambitions for science and technology, the chancellor, George Osborne, identified regenerative medicine as one of eight areas of technology in which he wanted the UK to become a world leader. Earlier last year, the Lords science and technology committee launched an inquiry into the potential of regenerative medicine in the UK – not only the science but what regulatory obstacles there might be to turning the knowledge into medical applications.

At Oxford, Riley has spent almost a year setting up a £2.5m lab, funded as part of the British Heart Foundation’s Mending Broken Hearts appeal, to work out how to get heart muscle to repair itself. The idea is to expand the scope of the work that got Riley into the headlines last year after a high-profile paper published in the journal Nature in which he showed a means of repairing cells damaged during a heart attack in mice. That work involved in effect turning the clock back in a layer of cells on the outside of the heart, called the epicardium, making adult cells think they were embryos again and thereby restarting their ability to repair.

During the development of the embryo, the epicardium turns into the many types of cells seen in the heart and surrounding blood vessels. After the baby is born this layer of cells loses its ability to transform. By infusing the epicardium with the protein thymosin ?4 (T?4), Riley’s team found the once-dormant layer of cells was able to produce new, functioning heart cells. Overall, the treatment led to a 25% improvement in the mouse heart’s ability to pump blood after a month compared with mice that had not received the treatment.

[div class=attrib]Read the entire article after the jump.[end-div]

[div class=attrib]Image courtesy of Google Search.[end-div]