Navigation Links
Macrophage proliferation appears to drive progression of atherosclerosis

New insights into the development of vulnerable atherosclerotic plaques could lead to better treatment or prevention of heart attacks and strokes. In a report being published online in Nature Medicine, researchers at the Massachusetts General Hospital (MGH) Center for Systems Biology re-evaluated previous assumptions regarding the role of inflammatory cells in atherosclerosis and found that the process relies on proliferation of certain immune cells within plaques and not exclusively on the uptake of cells from the blood.

The prevailing theory of atherosclerosis has been that plaques grow by drawing white blood cells called monocytes in from the circulation. These monocytes then mature into macrophages, cells that ingest lipid and cholesterol molecules but remain within the plaques, leading to the buildup of a fatty core that contributes to the risk of plaque rupture. While it had been believed that each macrophage descended from a single monocyte that had entered a plaque, the MGH team found that proliferation of new macrophages within plaques is a major driver of their growth.

"Currently, there is quite a bit of interest in targeting inflammation as a way to treat vascular disease, and one of the ways to do so is by targeting the cells responsible, says Filip Swirski, PhD, of the MGH Center for Systems Biology, senior author of the Nature Medicine report. "We discovered that the atherosclerotic lesion is a very dynamic environment, and even though the macrophages within a lesion are fundamentally derived from monocytes, they do not require constant monocyte input to sustain their numbers."

In a series of experiments in mice, the MGH-CSB team first found that existing plaques within the aortas of animals fed a high-cholesterol diet showed evidence of a rapid and constant proliferation of macrophages that did not require the presence of monocytes in the blood. Although monocytes were needed for the initiation of atherosclerosis, once plaques had formed, macrophage proliferation became the primary mechanism for the further growth of plaques. The investigators also identified a receptor protein on macrophages that appears to contribute to their proliferation within plaques without the involvement of monocytes. While further study is required to determine whether the same processes occur in humans, the MGH team did find evidence of macrophage proliferation in plaques from human carotid arteries.

"I think this work will force some major re-evaluations," says Swirski, an assistant professor of Radiology at Harvard Medical School. "People have been thinking of targeting monocyte influx to treat atherosclerosis, but they need to consider macrophage proliferation as an additional or alternative approach, especially in established disease. That might actually be better than targeting circulating monocytes, since interrupting pathological processes within the plaques themselves could spare the beneficial immune responses mediated by monocytes."


Contact: Sue McGreevey
Massachusetts General Hospital

Related medicine news :

1. CWRU School of Medicine researchers discover gene that permanently stops cancer cell proliferation
2. TG02 Potently Inhibits the Proliferation and Survival of Multiple Myeloma Cell Lines through Depletion of the Key Survival Protein MCL-1
3. Soy-based compound may reduce tumor cell proliferation in colorectal cancer
4. Off-Label Drug Use Appears Common
5. Exercise Appears to Ease Nerve-Damage Pain in Rat Study
6. New Pill Appears Effective, Safe for Ulcerative Colitis: Study
7. New Drug Appears to Extend Survival in Advanced Prostate Cancer Patients
8. Ancient Genome Appears to Have Links to Modern Humans
9. Decline in incidence of heart attacks appears associated with smoke-free workplace laws
10. Meditation appears to produce enduring changes in emotional processing in the brain
11. Experimental Antidepressant Appears Quick-Acting, Safe
Post Your Comments:
(Date:6/25/2016)... ... ... of Bruton Memorial Library on June 21 due to a possible lice infestation, as reported ... head lice: the parasite’s ability to live away from a human host, and to infest ... in the event that lice have simply gotten out of control. , As lice are ...
(Date:6/25/2016)... (PRWEB) , ... June 25, 2016 , ... ... athletes and non-athletes recover from injury. Recently, he has implemented orthobiologic procedures as ... City area —Johnson is one of the first doctors to perform the treatment. ...
(Date:6/24/2016)... ... ... Those who have experienced traumatic events may suffer from a complex set of ... or alcohol abuse, as a coping mechanism. To avoid this pain and suffering, Serenity ... event. , Trauma sufferers tend to feel a range of emotions, from depression, guilt, ...
(Date:6/24/2016)... ... June 24, 2016 , ... Global law firm Greenberg ... Legal Elite. The attorneys chosen by their peers for this recognition are considered among ... Greenberg Traurig Shareholders received special honors as members of this year’s Legal Elite Hall ...
(Date:6/24/2016)... ... 24, 2016 , ... People across the U.S. are sharpening their pencils and ... essay contest in which patients and their families pay tribute to a genetic counselor ... National Society of Genetic Counselors (NSGC) Annual Education Conference (AEC) this September. , ...
Breaking Medicine News(10 mins):
(Date:6/24/2016)... , June 24, 2016 According ... by Type (Standard Pen Needles, Safety Pen Needles), Needle ... GLP-1, Growth Hormone), Mode of Purchase (Retail, Non-Retail) - ... This report studies the market for the forecast period ... reach USD 2.81 Billion by 2021 from USD 1.65 ...
(Date:6/23/2016)... 23, 2016  MedSource announced today that it ... software solution of choice.  This latest decision demonstrates ... to their clients by offering a state-of-the-art electronic ... establishes nowEDC as the EDC platform of choice ... clients.  "nowEDC has long been a preferred EDC ...
(Date:6/23/2016)... -- In a startling report released today, National Safety Council ... comprehensive, proven plan to eliminate prescription opioid overdoses. Prescription ... are tackling the worst drug crisis in recorded U.S. history, assigned ... Kentucky , New Mexico , ... 28 failing states, three – Michigan , ...
Breaking Medicine Technology: