Heart Disease Vaccine Shows Promise In Animal Studies
The La Jolla Institute for Allergy and Immunology (LIAI) outside of San Diego, CA recently announced promising results for a vaccine to treat and prevent heart disease. The shot can be given before the onset of disease or after confirmation of plaque buildup in the arteries, and has shown to decrease this buildup by 40%.
Heart and Lungs diagram from Gray’s anatomy/public domain
For a long time, plaque was thought to be composed entirely of low-density lipoprotein (LDL; “bad” cholesterol); decrease one’s intake of LDL, decrease the risk of heart disease. More recently, it was found that while LDL is a component of the plaques, it is the immune system’s response to this increase in LDL that causes inflammation and enlarges plaques to the point of rupturing.
Armed with this new knowledge, researchers, including those at the LIAI, sought to reign in the effects of the immune system to the point where LDL is much more tolerated. The hypothesis was that blocking the immune system in plaques would increase the amount of time an individual has to remedy the LDL buildup while decreasing the risk of atherosclerosis and heart disease. The issues though were twofold: first, in small amounts LDL is a necessary component, so a strong vaccine would remove all LDL, damaging a patient; second, LDL is composed of the same substances as other lipoproteins, such as HDL (“good” cholesterol), meaning a vaccine targeted to the lipoprotein components may decrease amounts of other, better cholesterol.
Dr. Klaus Ley, a vascular immunologist at LIAI, explained how they circumvented these issues: “Our vaccine works more like the desensitization process used in allergy shots. Allergy shots are designed to teach the individual’s immune system to tolerate the allergen. Our vaccine would work on the same principle–only in this case we’d be teaching the immune system to tolerate certain molecules of our own bodies that it mistakenly attacks, which causes inflammation.”
This toleration of the body’s own molecules worked extremely well. By injecting mice with murine-derived proteins specific to the inflammatory response to lipoproteins, the researchers were able to “teach” the immune system to tolerate the LDL rather than attack it. This approach decreased arterial plaque buildup in mice by 40%.
The conclusions of the publication were simple, but the impact could be huge. As of now, 1 in every 4 Americans a year die of heart disease, totaling 600,000 deaths and $109 billion in health care costs and lost productivity. Heart disease and its complications are the number one killer in the world (8.5 million people annually). Provided the animal studies continue to show positive results, the vaccine could enter human trials, and a blockbuster market, in as little as three years.
Edward Marks is a PhD student at the University of Delaware. His research involves the healing of myocardial tissue after major cardiac events using nanomedicine techniques, with the goal of pushing any advancement directly into the clinic. Edward received his BS from Rutgers University and Masters from the University of Delaware.
