Scientists remove amyloid plaques from brains of live animals with Alzheimer's disease

October 15, 2009

A breakthrough discovery by scientists from the Mayo Clinic in Jacksonville, FL, may lead to a new treatment for Alzheimer's Disease that actually removes amyloid plaques--considered a hallmark of the disease--from patients' brains. This discovery, published online in The FASEB Journal (http://www.fasebj.org), is based on the unexpected finding that when the brain's immune cells (microglia) are activated by the interleukin-6 protein (IL-6), they actually remove plaques instead of causing them or making them worse. The research was performed in a model of Alzheimer's disease established in mice.

"Our study highlights the notion that manipulating the brain's immune response could be translated into clinically tolerated regimens for the treatment of neurodegenerative diseases," said Pritam Das, co-author of the study, from the Mayo Clinic in Jacksonville, FL.

Das and colleagues made this unexpected discovery when they initially set out to prove that the activation of microgila trigger inflammation, making the disease worse. Their hypothesis was that microglia would attempt to remove the plaques, but would be unable to do so, and in the process cause excessive inflammation. To the surprise of the researchers, when microglia were activated by IL-6, they cleared the plaques from the brains.

To do this, the researchers over-expressed IL-6 in the brains of newborn mice that had yet to develop any amyloid plaques, as well in mice with pre-existing plaques. Using somatic brain transgenesis technology, scientists analyzed the effect of IL-6 on brain neuro-inflammation and plaque deposition. In both groups of mice, the presence of IL-6 lead to the clearance of amyloid plaques from the brain. Researchers then set out to determine exactly how IL-6 worked to clear the plaques and discovered that the inflammation induced by IL-6 directed the microglia to express proteins that removed the plaques. This research suggests that manipulating the brain's own immune cells through inflammatory mediators could lead to new therapeutic approaches for the treatment of neurodegenerative diseases, particularly Alzheimer's disease.

"This model is as close to human pathology as animal models get. These results give us an exciting lead to newer, more effective treatments of Alzheimer's disease," said Gerald Weissmann, M.D., Editor-in-Chief of The FASEB Journal. "This study demonstrates that investment in experimental biology is the best way to approach the challenge posed by an aging population to the cost of health care."
-end-
Receive monthly highlights from The FASEB Journal by e-mail. Sign up at http://www.faseb.org/fasebjournalreaders.htm. The FASEB Journal (http://www.fasebj.org) is published by the Federation of the American Societies for Experimental Biology (FASEB). The journal has been recognized by the Special Libraries Association as one of the top 100 most influential biomedical journals of the past century and is the most cited biology journal worldwide according to the Institute for Scientific Information. FASEB comprises 22 nonprofit societies with more than 80,000 members, making it the largest coalition of biomedical research associations in the United States. FASEB advances health and welfare by promoting progress and education in biological and biomedical sciences through service to its member societies and collaborative advocacy.

Details: Paramita Chakrabarty, Karen Jansen-West, Amanda Beccard, Carolina Ceballos-Diaz, Yona Levites, Christophe Verbeeck, Abba C. Zubair, Dennis Dickson, Todd E. Golde, and Pritam Das. Massive gliosis induced by interleukin-6 suppresses A deposition in vivo: evidence against inflammation as a driving force for amyloid deposition. FASEB J. doi:10.1096/fj.09-141754 ; http://www.fasebj.org/cgi/content/abstract/fj.09-141754v2

Federation of American Societies for Experimental Biology

Related Immune Cells Articles from Brightsurf:

Gut immune cells may help send MS into remission
An international research team led by UCSF scientists has shown, for the first time, that gut immune cells travel to the brain during multiple sclerosis (MS) flare-ups in patients.

Immune cells sculpt circuits in the brain
Brain immune cells, called microglia, protect the brain from infection and inflammation.

How tumor cells evade the immune defense
Scientists are increasingly trying to use the body's own immune system to fight cancer.

Breast cancer cells can reprogram immune cells to assist in metastasis
Johns Hopkins Kimmel Cancer Center investigators report they have uncovered a new mechanism by which invasive breast cancer cells evade the immune system to metastasize, or spread, to other areas of the body.

Breast cancer cells turn killer immune cells into allies
Researchers at Johns Hopkins University School of Medicine have discovered that breast cancer cells can alter the function of immune cells known as Natural killer (NK) cells so that instead of killing the cancer cells, they facilitate their spread to other parts of the body.

Engineered immune cells recognize, attack human and mouse solid-tumor cancer cells
CAR-T therapy has been used successfully in patients with blood cancers such as lymphoma and leukemia.

Mapping immune cells in brain tumors
It is not always possible to completely remove malignant brain tumors by surgery so that further treatment is necessary.

Nutrient deficiency in tumor cells attracts cells that suppress the immune system
A study led by IDIBELL researchers and published this week in the American journal PNAS shows that, by depriving tumor cells of glucose, they release a large number of signaling molecules.

Experience matters for immune cells
The discovery that immune T cells have a spectrum of responsiveness could shed light on how our immune system responds to infections and cancer, and what goes wrong in immune diseases.

Immune cells against Alzheimer's?
German researchers have developed a novel, experimental approach against Alzheimer's.

Read More: Immune Cells News and Immune Cells Current Events
Brightsurf.com is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to Amazon.com.