Navigation Links
Rare hybrid cell key to regulating the immune system
Date:5/24/2010

AUGUSTA, Ga. - A cell small in number but powerful in its ability to switch the immune system on or off is a unique hybrid of two well-known immune cell types, Medical College of Georgia researchers report.

"This is actually the first cell we know of that has this type of appearance in nature," Dr. Andrew Mellor, molecular geneticist and immunologist who co-directs MCG's Immunotherapy Discovery Institute, said of the cell that looks like a dendritic cell and a B cell but isn't really either.

The discovery of this rare hybrid could have implications for the efficacy of new therapies that manipulate these two cell types to treat diseases such as cancer and rheumatoid arthritis.

When MCG scientists first reported the human equivalent of this cell in Science in 2002, they called it a subset of the dendritic cell that clusters in high exposure areas such as the gut but also roams the body, looking for invaders like a virus or cancer. Dendritic cells show their find to T cells, telling them to ignore or attack by bringing trash-eating macrophages, natural killer cells and the like into the fight.

What seemed most unique about the subset is its ability to express indoleamine 2,3 dioxygenase, or IDO, to turn off T cells. IDO is an enzyme used by fetuses and tumors alike to escape the immune response.

The new studies show that is only part of the cells' distinctiveness. The cells also have the identifying markings of B cells, known for their ability to make antibodies against invaders. In fact, they found the IDO-presenting cells came from the same precursor cell as B cells. But, when the scientists looked at mice missing B cells, they still found the IDO-producing cells. Hence, the cell didn't need to produce antibodies to turn off T cells.

In reality, IDO-expressing cells have properties of both cells, said Burles A. Johnson III, an MCG M.D.-Ph.D. student and first author of the paper published online this week in PNAS. "It looks like a B cell and it's not. It looks like a dendritic cell and it is and it isn't," Johnson said.

While their studies are in mice, the cells also are in humans, showing up in some unfortunate places such as the drainage system for tumors, melanoma or even HIV where they likely help the diseases survive.

They also may be showing up in new dendritic cell therapies designed to strengthen the immune response to cancer. If the therapies happen to include some IDO-expressing cells, those could end up helping the cancer, said Mellor, the paper's corresponding author. "All you need is a few of these cells in your dendritic cell vaccine and you don't get stimulation any more, you get suppression," Mellor said.

Their confusing face could also cause hybrids to be lost in B cell-depleting therapies designed to lessen the immune system's attack on joints in rheumatoid arthritis. "These therapies may also deplete IDO-expressing cells and decrease therapy effectiveness because you are eliminating cells that are there to help you," Johnson said.

"This gives us new insight into why these therapies might not be working as well as we think they might," Mellor added. Long-term goals include figuring out how to manipulate the hybrid's activity to benefit patients.


'/>"/>

Contact: Toni Baker
tbaker@mcg.edu
706-721-4421
Medical College of Georgia
Source:Eurekalert  

Related medicine news :

1. Phybridge Named "Cool Vendor" by Leading Analyst Firm
2. TCT for Surgeons course will highlight hybrid surgical and interventional techniques
3. Phybridge Inc. Joins the Cisco Developer Network and Completes Cisco Interoperability Verification Testing
4. Howard Leights New Pilot Push-in Ear Plug Delivers Occupational Hearing Protection with Innovative, Hybrid Design
5. Mount Sinai discovers bone marrow plays critical role in enhancing immune response to viruses
6. New Blue Ocean Load & Go™ CR Series Immune Monitoring Systems Debut at ISAC CYTO 2010
7. ASCO data highlight novel anti-cancer approach that exposes tumors to immune attack
8. New Clues to Treating Immune System Disorders
9. PET scanning probes reveal different cell function within the immune system
10. Immunetics Wins $2.8 Million Contract for New Type of HIV Test
11. New Diagnostic Testing Company, Blue Ocean Biomedical, Specializes In Automated, Load & Go Cell Analysis Systems For Immune Monitoring
Post Your Comments:
*Name:
*Comment:
*Email:
Related Image:
Rare hybrid cell key to regulating the immune system
(Date:3/23/2017)... New York, NY (PRWEB) , ... March 23, 2017 , ... 82% of adults are ... every 3 kids do not brush their teeth the minimum two times a day that ... teeth; with students missing 51 million hours of school and adults missing 164 million hours ...
(Date:3/23/2017)... (PRWEB) , ... March 23, 2017 , ... ... investment in Los Angeles based healthcare technology company California Healthcom Group (CHG). ... the US, and healthcare arena. With headquarters in California, CHG is a growing, ...
(Date:3/23/2017)... ... March 23, 2017 , ... After raising more than ... , the most-funded travel pillow in crowdfunding history, has established a U.S. ... wildly popular travel innovation to Americans. , “We’re excited to be operating on U.S. ...
(Date:3/23/2017)... Los Angeles, CA (PRWEB) , ... March 23, 2017 , ... ... half of all Americans, yet poor sleep is likely not the only cause of ... these undesirable characteristics that make you look older or in poor health are likely ...
(Date:3/23/2017)... (PRWEB) , ... March 23, 2017 , ... The American ... 2017 marks the 40th Anniversary of ABQAURP’s dedication to Health Care Quality and Management ... who have contributed not only to the association, but also to the Health Care ...
Breaking Medicine News(10 mins):
(Date:3/23/2017)... March 23, 2017  A new genetic test ... identification of individuals who carry HLA-B*15:02 ... rare yet potentially deadly side effect of certain ... The gene HLA-B*15:02 is strongly associated ... Stevens-Johnson syndrome and toxic epidermal necrolysis in patients ...
(Date:3/23/2017)... On Wednesday, March 22, ... at 5,821.64, up 0.48%; the Dow Jones Industrial ... and the S&P 500 closed at 2,348.45, slightly ... out of nine sectors ended the day in ... on the following Medical Instruments & Supplies equities: ...
(Date:3/23/2017)... 23, 2017 Pre-market today, Stock-Callers.com has ... (NYSE: AGN), Horizon Pharma PLC (NASDAQ: HZNP), and Evoke Pharma ... are part of the Healthcare sector, which was slightly higher ... with the NYSE Health Care Index adding about 0.1% in ... 500 also were up nearly 0.1% as a group. Learn ...
Breaking Medicine Technology: