Targeting T cells to control their behaviour in heart disease

Investigating the topography of effector and regulatory immunity in the cardiovascular system: Basic mechanisms and therapeutic potential (renewal)

Coronary heart disease (CHD) can be caused by the inappropriate behaviour of T cells—a type of immune cell. Although T cells help us fight infection, sometimes their action on the heart and blood vessels is unwanted. T cells can contribute to the build-up of dangerous plaques in blood vessels, a condition called atherosclerosis. They have also been shown to be involved in the metabolic syndrome, a combination of diabetes, high blood pressure and obesity, and in myocarditis – inflammation of the heart. T cells are also involved in the body’s response to transplantation, helping the immune system reject donor hearts after a heart transplant. To control T-cell behaviour in different parts of the body, scientists need to understand what drives some T cells to travel to specific body tissues or organs. This is the basis for Professor Marelli-Berg's 5-year programme of research at Queen Mary University of London. The research will focus on identifying which T cells travel to the heart and blood vessel walls to cause inflammation, and what processes affect this migration, including whether metabolic imbalances can affect T-cell movement. Recently, Professor Marelli-Berg’s group identified a new molecular pathway that directs T-cell movement to the heart. They have shown that by blocking this pathway, they can prevent rejection of heart transplants without affecting the rest of the immune system. This breakthrough discovery could lead to new ways of blocking the immune response in the heart selectively without the severe side effects (such as infections and cancer) that affect transplant patients taking conventional immune blockers, which impair the whole body’s immune responses. Blocking the new ‘heart homing’ pathway may also help to combat T cell infiltration and heart damage in myocarditis.