Featured Research

from universities, journals, and other organizations

Recently Discovered Cell Is Unexpected Player In Psoriasis

Date:
January 30, 2008
Source:
Rockefeller University
Summary:
When the FDA assesses a drug, it looks closely at its safety and its effectiveness, but it doesn't require a precise understanding of how the drug works. A new study shows that a strikingly successful psoriasis drug, etanercept, may not act on the immune cells that scientists had originally believed. In fact, their findings indicate that the disease itself may be partially driven by these recently discovered cells.

Second skin. New research suggests that the psoriasis drug etanercept targets dendritic cells (red), preventing them from producing tumor necrosis factor or TNF (green), a molecule associated with the skin disease. Compared with skin from a pretreatment patient (top), skin from a patient treated with the drug for two weeks has dramatically less TNF.
Credit: Image courtesy of Rockefeller University

When the FDA assesses a drug, it looks closely at its safety and its effectiveness, but it doesn’t require a precise understanding of how the drug works. A new study by Rockefeller University scientists shows that a strikingly successful psoriasis drug, etanercept, may not act on the immune cells that scientists had originally believed. In fact, their findings indicate that the disease itself may be partially driven by these recently discovered cells.

Related Articles


T helper or “Th” cells play a vital role in coordinating immune response. Until now, one of these types of helper cells, called Th1, was believed to be a major contributor to psoriasis because it produces a molecule called interferon gamma, which is strongly associated with the disease. But by looking at the reactions of immune cells to etanercept, James Krueger — head of the Laboratory of Investigative Dermatology and D. Martin Carter Professor in Clinical Investigation — and his colleagues found that a newly discovered helper cell, Th17, may play a major role in the disease.

Most studies of psoriasis drugs to date have begun looking at patients’ disease profiles four weeks after the treatment starts. But by that point, says biomedical fellow and first author Lisa Zaba, “all the action is over.” Instead, she decided to look not just at a patient’s latent response to etanercept treatment but also at what happens during the first few weeks. “We really wanted to discern patterns of action, so we could determine what’s happening first, what’s happening second,” she says. “That way, we can go back to the immune system and figure out which cells are partially responsible.”

By watching 20 different patients’ immune reactions to etanercept at four different time points — at the end of one week, two weeks, four weeks and 12 weeks — an interesting pattern began to emerge. At the end of week one, the drug had already decreased the activity of Th17 cells. It wasn’t until the 12th week, however, that interferon gamma levels decreased, indicating that the Th1 cells had been downregulated. “That raises the logical question,” Zaba says. “If this is supposed to be a Th1 disease, why are patients getting better before their Th1 activity goes down?”

When Zaba and her colleagues tried to answer this question, they discovered that the problem likely goes far beyond Th1 cells. In fact, Zaba says, “the dendritic cell is possibly more central to this disease.” Dendritic cells, which are responsible for directing immune response and which have receptors on their surface that etanercept prevents from activating, can’t mature and activate Th cells when the drug is present.

The more scientists understand about how psoriasis works, the better equipped they are to make therapies that treat it. By understanding the immune reaction in more detail, researchers will be able to create a drug more specific than etanercept, and one that can be even more effective.

Journal reference: Journal of Experimental Medicine online: November 26, 2007


Story Source:

The above story is based on materials provided by Rockefeller University. Note: Materials may be edited for content and length.


Cite This Page:

Rockefeller University. "Recently Discovered Cell Is Unexpected Player In Psoriasis." ScienceDaily. ScienceDaily, 30 January 2008. <www.sciencedaily.com/releases/2008/01/080124140754.htm>.
Rockefeller University. (2008, January 30). Recently Discovered Cell Is Unexpected Player In Psoriasis. ScienceDaily. Retrieved November 28, 2014 from www.sciencedaily.com/releases/2008/01/080124140754.htm
Rockefeller University. "Recently Discovered Cell Is Unexpected Player In Psoriasis." ScienceDaily. www.sciencedaily.com/releases/2008/01/080124140754.htm (accessed November 28, 2014).

Share This


More From ScienceDaily



More Health & Medicine News

Friday, November 28, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Rural India's Low-Cost Sanitary Pad Revolution

Rural India's Low-Cost Sanitary Pad Revolution

AFP (Nov. 28, 2014) — One man hopes his invention -– a machine that produces cheap sanitary pads –- will help empower Indian women. Duration: 01:51 Video provided by AFP
Powered by NewsLook.com
Research on Bats Could Help Develop Drugs Against Ebola

Research on Bats Could Help Develop Drugs Against Ebola

AFP (Nov. 28, 2014) — In Africa's only biosafety level 4 laboratory, scientists have been carrying out experiments on bats to understand how virus like Ebola are being transmitted, and how some of them resist to it. Duration: 01:18 Video provided by AFP
Powered by NewsLook.com
WHO Says Male Ebola Survivors Should Abstain From Sex

WHO Says Male Ebola Survivors Should Abstain From Sex

Newsy (Nov. 28, 2014) — WHO cites four studies that say Ebola can still be detected in semen up to 82 days after the onset of symptoms. Video provided by Newsy
Powered by NewsLook.com
Ebola Leaves Orphans Alone in Sierra Leone

Ebola Leaves Orphans Alone in Sierra Leone

AFP (Nov. 27, 2014) — The Ebola epidemic sweeping Sierra Leone is having a profound effect on the country's children, many of whom have been left without any family members to support them. Duration: 01:02 Video provided by AFP
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