Featured Research

from universities, journals, and other organizations

A 24-karat gold key to unlock the immune system

Date:
March 26, 2012
Source:
American Friends of Tel Aviv University
Summary:
Using nanoparticles made of pure gold, researchers have developed a new method of introducing chemical residues into the immune system, triggering immune cells to help the body fight infection. The breakthrough could lead to an increased understanding of viruses and bacteria, better drug delivery systems, and more effective medications and vaccinations.

Gold particles modified with chemical residues interact with immune cells.
Credit: Prof. Vincent Rotello

Developing a drug or vaccine requires a delicate balancing act with the immune system. On one hand, medications need to escape detection by the immune system in order to perform their function. But vaccinations -- de-activated versions of a disease or virus -- need to do the reverse. They prompt the immune system to create protective antibodies. But scientists are still stumped by how the immune system recognizes different particles, and how it chooses whether or not to react against them.

Related Articles


Using nanoparticles made of pure gold, Dr. Dan Peer, head of Tel Aviv University's Laboratory of Nanomedicine at the Department of Cell Research and Immunology and the Center for Nanoscience and Nanotechnology, with a team including Drs. Meir Goldsmith and Dalit Landesman-Milo and in collaboration with Prof. Vincent Rotello and Dr. Daniel Moyano from the University of Massachusetts at Amherst, has developed a new method of introducing chemical residues into the immune system, allowing them to note the properties that incur the wrath of immune cells. Because the gold flecks are too small to be detected by the immune system, the immune system only responds when they are coated with different chemical residues.

This breakthrough could lead to an increased understanding of the properties of viruses and bacteria, better drug delivery systems, and more effective medications and vaccinations. Their study was published in the Journal of the American Chemical Society.

A tool for exploration

To begin probing the immune system, researchers used particles of gold, approximately two nanometers in diameter, and covered them with various chemical residues. Only when water-resistant residues were introduced did the immune system respond to their presence. That established a demonstrable link between hydrophobicity -- the degree to which a molecule repels water -- and the reaction of the immune system.

This idea has a basis in the normal functioning of the immune system, Dr. Peer explains. During cell death, the hydrophobic areas of the cell membrane become exposed. The immune system then realizes that damage has occurred and begins to alert neighboring cells.

The researchers discovered that the same principle held true for the chemicals added to the gold particles' surface. The more "water-hating" the particle is, the more actively the immune system will mobilize against it, he says.

Dr. Peer observes that this is only the first step in a long line of experiments. "We are using these gold particles to tackle the question of how the immune system recognizes different particles, which might include features such as geometry, charge, curvature, and so much more. Now that we know the tool works, we can build on it," he says.

Testing the "Danger Model"

Until now, scientists have developed theories about how the immune system functions, but have lacked the machinery to test these ideas. One such theory is the "Danger Model" by Prof. Polly Matzinger, which hypothesizes that cellular damage interacts with immune cells at the membrane level. Once they identify the foreign molecule as a "danger," the immune cells send signals throughout the immune system. Their initial experiment with hydrophobicity was designed to generate a toolbox for probing this theory, says Dr. Peer, whose investigations included both in vitro and in vivo experiments using mouse immune cells.

In the future, researchers will study various bacterial, viral, or damaged cells and to make the gold nanoparticles even more similar, thereby discovering which elements of dangerous particles are calling the body's immune system to arms. "We now have the capability of using nanomaterials to probe the immune system in a very accurate manner," says Dr. Peer, a breakthrough that could revolutionize the way we understand the immune system.


Story Source:

The above story is based on materials provided by American Friends of Tel Aviv University. Note: Materials may be edited for content and length.


Journal Reference:

  1. Daniel F. Moyano, Meir Goldsmith, David J. Solfiell, Dalit Landesman-Milo, Oscar R. Miranda, Dan Peer, Vincent M. Rotello. Nanoparticle Hydrophobicity Dictates Immune Response. Journal of the American Chemical Society, 2012; 134 (9): 3965 DOI: 10.1021/ja2108905

Cite This Page:

American Friends of Tel Aviv University. "A 24-karat gold key to unlock the immune system." ScienceDaily. ScienceDaily, 26 March 2012. <www.sciencedaily.com/releases/2012/03/120326160907.htm>.
American Friends of Tel Aviv University. (2012, March 26). A 24-karat gold key to unlock the immune system. ScienceDaily. Retrieved December 21, 2014 from www.sciencedaily.com/releases/2012/03/120326160907.htm
American Friends of Tel Aviv University. "A 24-karat gold key to unlock the immune system." ScienceDaily. www.sciencedaily.com/releases/2012/03/120326160907.htm (accessed December 21, 2014).

Share This


More From ScienceDaily



More Health & Medicine News

Sunday, December 21, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

The Best Tips to Curb Holiday Carbs

The Best Tips to Curb Holiday Carbs

Buzz60 (Dec. 19, 2014) It's hard to resist those delicious but fattening carbs we all crave during the winter months, but there are some ways to stay satisfied without consuming the extra calories. Vanessa Freeman (@VanessaFreeTV) has the details. Video provided by Buzz60
Powered by NewsLook.com
Sierra Leone Bikers Spread the Message to Fight Ebola

Sierra Leone Bikers Spread the Message to Fight Ebola

AFP (Dec. 19, 2014) More than 100 motorcyclists hit the road to spread awareness messages about Ebola. Nearly 7,000 people have now died from the virus, almost all of them in west Africa, according to the World Health Organization. Video provided by AFP
Powered by NewsLook.com
Researchers Test Colombian Village With High Alzheimer's Rates

Researchers Test Colombian Village With High Alzheimer's Rates

AFP (Dec. 19, 2014) In Yarumal, a village in N. Colombia, Alzheimer's has ravaged a disproportionately large number of families. A genetic "curse" that may pave the way for research on how to treat the disease that claims a new victim every four seconds. Duration: 02:42 Video provided by AFP
Powered by NewsLook.com
The Best Protein-Filled Foods to Energize You for the New Year

The Best Protein-Filled Foods to Energize You for the New Year

Buzz60 (Dec. 19, 2014) The new year is coming and nothing will energize you more for 2015 than protein-filled foods. Fitness and nutrition expert John Basedow (@JohnBasedow) gives his favorite high protein foods that will help you build muscle, lose fat and have endless energy. Video provided by Buzz60
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:

Strange & Offbeat Stories


Health & Medicine

Mind & Brain

Living & Well

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins