Navigation Links
New insights into how immune system fights atherosclerosis
Date:12/21/2012

New York, NY (December 21, 2012) A study led by Columbia University Medical Center (CUMC) researchers has found that an important branch of the immune system, in reaction to the development of atherosclerotic lesions, mounts a surprisingly robust anti-inflammatory T cell response that helps prevent the disease from progressing. The findings may help inform the design of anti-atherosclerosis vaccines and other therapies that can take advantage of this aspect of the immune system. The study was published today in the online edition of the Journal of Clinical Investigation.

When the body encounters viruses, bacteria, or other potential threats, dendritic cells the sentinels of the immune system are dispatched to take a sample of the pathogen and present it to T cells. This activates the production of pro-inflammatory effector T cells (which attack the pathogen) and anti-inflammatory regulatory T cells (which keep the pro-inflammatory response in check).

"Normally, the pro-inflammatory response dominates, and that is what people assumed to be the case in atherosclerosis," said study leader Ira Tabas, MD, PhD, the Richard J. Stock Professor, Department of Medicine, and professor of pathology & cell biology (in physiology and cellular biophysics) at CUMC. "However, we found that the T cell response to atherosclerosis is mostly anti-inflammatory."

The researchers, led by postdoctoral scientist Manikandan Subramanian, PhD, used mice whose dendritic cells lacked MYD88, a signaling protein that initiates the cells' maturation. Since immature dendritic cells cannot activate T cells, the elimination of MYD88 effectively disabled the production of both effector and regulatory T cells. The mice were also bred to lack the LDL receptor, leaving them prone to the development of atherosclerosis.

The net effect of these changes in the mice was to increase the size of atherosclerotic lesions. "What this means is that the dominant effect of dendritic cells in the setting of atherosclerosis is to promote the development of protective regulatory T cells," said Dr. Tabas.

Earlier studies had suggested just the opposite: that effector T cells dominate in response to atherosclerosis. "In those studies, researchers disabled dendritic cells at an earlier stage, creating all sorts of compensatory processes," said Dr. Tabas. "That's probably why they came to a different conclusion. In our model, we were able to knock out only the step involved in activating T cells, leaving everything else alone."

The researchers found that T regulatory cells act by suppressing pro-inflammatory effector T cells and macrophages, which was expected. They also identified a new mechanism that directly links regulatory-T-cell activation with protection from atherosclerosis. According to Dr. Tabas, regulatory T cells secrete TGF-beta (a cytokine, or signaling molecule), which suppresses MCP-1 (monocyte chemoattractant protein-1), a protein that recruits monocytes, a type of white blood cell.

"Now we have a specific mechanism that could explain the preclinical success of dendritic vaccines and that provides a new understanding of how these vaccines might be improved," said Dr. Tabas.


'/>"/>
Contact: Karin Eskenazi
ket2116@columbia.edu
212-342-0508
Columbia University Medical Center
Source:Eurekalert

Related biology news :

1. New insights into cloud formation
2. Research on flavanols and procyanidins provides new insights into how these phytonutrients may positively impact human health
3. Battle of the sexes offers evolutionary insights
4. Study provides new insights into structure of heart muscle fibers
5. Study offers new insights into the effects of stress on pregnancy
6. Cell biology -- new insights into the life of microtubules
7. Yak genome provides new insights into high altitude adaptation
8. Zebrafish provide insights into causes and treatment of human diseases
9. Feces fossils yield new insights into ancient diets and thrifty genes
10. Piglets in mazes provide insights into human cognitive development
11. The ENCODE Project publishes new genomic insights in special issue of Genome Research
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:8/23/2017)... 23, 2017  The general public,s help is being enlisted in what,s ... live in and on the human body –and are believed to affect ... The Microbiome Immunity Project is ... starting with the gut. The project's goal is to help advance scientific ... ...
(Date:7/20/2017)... DAL ) customers now can use fingerprints instead of their ... (DCA). ... launches biometrics to board aircraft at Reagan Washington National Airport ... Delta,s biometric boarding pass experience that launched in May at ... process to allow eligible Delta SkyMiles Members who are enrolled in CLEAR ...
(Date:6/23/2017)... N.Y. and ITHACA, N.Y. ... ) and Cornell University, a leader in dairy research, ... with bioinformatics designed to help reduce the chances that ... With the onset of this dairy project, Cornell University ... Consortium for Sequencing the Food Supply Chain, a food ...
Breaking Biology News(10 mins):
(Date:10/11/2017)... ... October 11, 2017 , ... A new ... rates in frozen and fresh in vitro fertilization (IVF) transfer cycles. ... to IVF success. , After comparing the results from the fresh and frozen ...
(Date:10/10/2017)... (PRWEB) , ... October 10, 2017 , ... San Diego-based ... of its corporate rebranding initiative announced today. The bold new look is part ... as the company moves into a significant growth period. , It will also expand ...
(Date:10/10/2017)... ... October 10, 2017 , ... For the second time ... US2020 STEM Mentoring Award. Representatives of the FirstHand program travelled to Washington, D.C. ... US2020. , US2020’s mission is to change the trajectory of STEM education in ...
(Date:10/10/2017)... Oct. 10, 2017 International research firm Parks Associates ... speak at the TMA 2017 Annual Meeting , October 11 in ... the residential home security market and how smart safety and security products ... Parks Associates: Smart ... "The residential security market ...
Breaking Biology Technology: