AUG 31, 2017 12:38 PM PDT

Two Immune Cell Types Accidentally Promote Heart Disease

WRITTEN BY: Kara Marker

Prescribing drugs that lower “bad” cholesterol is a common approach to treating heart disease, but scientists from the Karolinska Institute think there may be another solution.

Histopathology of atherosclerosis. Credit: Wikimedia User Pathos

Atherosclerosis, a disease characterized by the development of plaques in blood vessels that impede blood flow, is a common marker of heart disease. Immune cells called T cells and dendritic cells are regular occupiers of atherosclerotic plaques, where a collection of these cells and other debris floating through blood vessels ultimately pack together and block the flow of oxygenated blood to the heart. By targeting these immune cells, Karolinska Institute scientists believe they could develop a method for treating heart disease completely separate from techniques focused on lowering low-density lipoprotein (LDL), AKA “bad” cholesterol.

The main “ingredient” of this new technique is a protein called PCSK9 (proprotein convertase subtilisin kexin 9). PCSK9 proteins degrade LDL receptors, which results in increased amounts of LDL. Thus, PCSK9 inhibitors are prescribed to lower LDL cholesterol. But there’s yet another use for PCSK9 inhibitors.

The scientists needed to find a way to inhibit immune cells promoting the formation of atherosclerotic plaques without suppressing the entire immune system. So, they needed to know what specifically activates the T cells and dendritic cells found in atherosclerotic plaques. They discovered two key players: PCSK9 and oxidized LDL.

When LDL becomes oxidized, a modification is made to the lipoprotein that promotes its interaction with and uptake by macrophages, making oxidized LDL a clear marker for cardiovascular disease.

Researchers collected T cells from carotid arteries from people with atherosclerosis and from healthy individuals. Dendritic cells were taken from human peripheral blood. They combined dendritic cells with oxidized LDL before adding in T cells.

They found that oxidized LDL both triggered production of PCSK9 proteins and induced dendritic cell maturation and T cell activation into helper cells. However, inhibiting PCSK9 reversed the effects.

“This changed a pro-inflammatory profile into an anti-inflammatory state that is potentially anti-atherosclerotic,” explained lead author Prof Johan Frostegård. “The benefits of PCSK9 inhibition extend beyond lowering LDL cholesterol.”

Source: Methods in Molecular Biology, European Society of Cardiology

About the Author
I am a scientific journalist and enthusiast, especially in the realm of biomedicine. I am passionate about conveying the truth in scientific phenomena and subsequently improving health and public awareness. Sometimes scientific research needs a translator to effectively communicate the scientific jargon present in significant findings. I plan to be that translating communicator, and I hope to decrease the spread of misrepresented scientific phenomena! Check out my science blog: ScienceKara.com.
You May Also Like
MAR 22, 2022
Cardiology
Stress Reduction May Help Treat Atrial Fibrillation
MAR 22, 2022
Stress Reduction May Help Treat Atrial Fibrillation
Americans are feeling unprecedented levels of stress; reducing it may help treat atrial fibrillation.
APR 06, 2022
Technology
Mobile App Predicts Genetic Risks for Coronary Artery Disease
APR 06, 2022
Mobile App Predicts Genetic Risks for Coronary Artery Disease
Coronary artery disease(CAD) is the most common form of heart disease, affecting about 18 million adult Americans each y ...
APR 19, 2022
Cardiology
Daily Coffee May Improve Longevity and Heart Health
APR 19, 2022
Daily Coffee May Improve Longevity and Heart Health
Good news for coffee fans!
MAY 09, 2022
Clinical & Molecular DX
COVID-19 Vaccine Technique Guiding Heart Disease Research
MAY 09, 2022
COVID-19 Vaccine Technique Guiding Heart Disease Research
The heart is made up in part of cardiomyocytes, specialized cells responsible for controlling heart beats. After a heart ...
JUN 30, 2022
Cardiology
Greenlanders Face Genetic Heart Risks
JUN 30, 2022
Greenlanders Face Genetic Heart Risks
About one third of Greenlanders are at higher risk of heart disease and high cholesterol.
JUL 07, 2022
Cardiology
Reduce TV Viewing to Prevent Heart Disease
JUL 07, 2022
Reduce TV Viewing to Prevent Heart Disease
According to new research, over 10% of coronary heart disease cases could be prevented by watching less than one hour of ...
Loading Comments...