Antibodies can protect against heart attacks, Trust researchers find

Antibodies could protect against heart attacks, according to research conducted at Imperial College London.

The research, which was funded by the National Institute for Health Research Comprehensive Biomedical Research Centre at Imperial College Healthcare NHS Trust, has been published this week in the journal EBioMedicine.

In collaboration with Lund University in Sweden, researchers studied a population of 10,000 patients with high blood pressure of which 87 had developed coronary heart disease (CHD) and measured the antibody levels in those who had heart attacks as well as control patients who did not. In a second study, in collaboration with researchers from the Thorax centre in Holland, they measured antibody levels in a further 143 patients who had their heart arteries imaged with cutting edge techniques.

Researchers found that those who had heart attacks in the first study, as well as those whose arteries had unstable fatty plaques in the second study, had much lower levels of an antibody called IgM anti MDA-LDL. In the first study, those with high levels had 70 per cent less chance of developing heart disease over nearly five years of follow up. The second study provided some explanation for those findings, in that those with highest levels of antibodies, were well protected from developing dangerous plaques that are more prone to rupturing and causing a heart attack.

Not only could this finding help doctors to more precisely identify patients at risk of heart attack, it also raises the possibility of using therapies that improve the immune system – such as vaccines and antibody injections  to reduce the risk of a heart attack.

The researchers don’t yet know why some people have higher levels of this specific antibody. Although, it may be that some people inherit these protective antibodies, others may have produced them in response to common bacterial infections in childhood.

Atherosclerosis is the build-up of fatty plaques in the walls of the arteries that lead to the brain or heart. If an atherosclerotic plaque ruptures, a deadly blood clot can form and block the blood supply to the heart or brain, causing either a heart attack or stroke. Each year in the UK over 100,000 people die as a result of atherosclerosis.

Lead researcher Dr Ramzi Khamis, consultant cardiologist at Imperial College Healthcare NHS Trust and BHF Clinical Research Fellow at the National Heart and Lung Institute, Imperial College London, said:

“We are one step closer to figuring out how the immune system protects from dangerous heart attacks. We hope that our research will help us find patients at the highest risk, as well as help us to develop therapies that target the immune system, which seems to play an important part in preventing heart attacks.”

Dr Noel Faherty, senior research advisor at the British Heart Foundation, which funded the research, said:

“Each year in the UK over 100,000 people die from a heart attack or stroke that has been caused by rupture of a fatty deposit, called a plaque, on the inside of an artery. By discovering which patients have plaques that are more likely to rupture and why we can save thousands of lives.

“We already know that our immune system takes part of the blame in causing these fatty deposits to form and rupture. But the whole story of how our immune system is involved in heart and circulatory diseases is a lot more complex. More research is needed, but in the future, we might be able use new drugs to tweak the immune system in different ways to prevent people having a heart attack or stroke.” 

Image courtesy of Imperial College London.