HOME >> MEDICINE >> NEWS
Old mystery solved, revealing origin of regulatory T cells that 'police' and protect the body

dendritic" cells within the thymus to eliminate these bad cells. T cells that pass both levels of selection are then released into the bloodstream to perform vital immune functions.

"It was believed that the only way to induce what is known as central tolerance was by deleting harmful T cells during development," says Liu.

But scientists now know that not all the "bad" T cells are destroyed through negative selection. Some autoreactive T cells escape the thymic censorship process and are released into the circulation. For that reason, researchers searched for additional mechanisms that exist in the blood and lymph system outside of the thymus to take care of these bad actors - which led to the discovery of regulatory T cells. These special T cells act like policemen to scour out dangerous T cells and suppress activation of the immune system, and thus maintain tolerance to self.

A major question in immunology was how regulatory T cells are developed in the thymus.

In 2002, in Nature Immunology, Liu and his research team revealed the existence of the chemical signal TSLP (thymic stromal lymphopoietin) that activates dendritic cells in the thymus. In 2004, they reported, also in Nature Immunology, that epithelial cells within Hassall's corpuscles express TSLP.

In this study, using human thymus tissue taken during cardiac surgery in children - tissue that otherwise would have been discarded " the researchers isolated different components of thymic cells, and reconstituted them in test tubes. They then conducted numerous experiments over several years, looking at different stages of T cell development and activation of dendritic cells.

They found that Hassall's corpuscles produce chemical signals that direct a specialized group of dendritic cells to turn some of the bad T cells into "good cop" regulatory T cells.

This means that the thymus is providing central tolerance not only through clonal deletion
'"/>

Contact: Nancy Jensen
nwjensen@mdanderson.org
713-792-0655
University of Texas M. D. Anderson Cancer Center
11-Oct-2005


Page: 1 2 3

Related medicine news :

1. UCLA, Italian chemists move closer to solving Lou Gehrigs disease mystery
2. Radiologists attempt to solve mystery of Tuts demise
3. Solution to bacterial mystery promises new drugs
4. St. Jude unlocks mystery of very aggressive leukemia
5. WA team uses baby tooth to solve death mystery
6. The upstairs/downstairs mystery of cell suicide is burdened by too much evidence
7. New book explains age-old mystery of geometrical illusions
8. Differential heart-attack risks among blacks, whites remain mystery
9. Exploring the molecular origin of blood clot flexibility
10. Higher levels of cells originating in bone marrow may be useful in prognosis of liver cancer
11. Tulane researcher reports on origin of deadly fever outbreak

Post Your Comments:
*Name:
*Comment:
*Email:


(Date:1/7/2020)... ... January 07, 2020 , ... ... for characterizing microbiome populations down to the strain level, has announced a ... organization. , TOMY provides high-quality instruments and services to industry segments including ...
(Date:1/7/2020)... ... January 07, 2020 , ... Red Oak ... Director of Foothills at Red Oak Recovery effective immediately. Ian began working ... the nation's leading residential treatment centers for adolescents. In this capacity, Ian worked ...
(Date:1/7/2020)... ... 06, 2020 , ... After 32 years in Stealth Mode, LumaCare ™ ... Duo ™. , The first public demonstrations of the LumaCare Duo will be given ... during CES 2020, the largest consumer electronics trade show and conference in the United ...
(Date:1/7/2020)... ... , ... R3 Stem Cell is now offering access to all regenerative training ... 24/7 and includes all the stem cell and exosome courses. , For several years, ... For the online regenerative training courses, R3 assembled all of the presentations and procedures ...
(Date:1/3/2020)... ... January 02, 2020 , ... ... lifestyle solutions, has announced the final round of U.S. finalists for its annual ... are Andrew Bischoff of Minnetonka, Minnesota; Ashley Pederson of St. Paul, Minnesota; Kim ...
Breaking Medicine News(10 mins):
(Date:1/7/2020)... , ... January 07, 2020 , ... ... enterprises and telecom service providers, announced today it has been selected by MetLife ... network infrastructure. , “As part of our ongoing commitment to maintain the ...
(Date:1/5/2020)... ... January 04, 2020 , ... The Voice First ... firms are fighting for leadership in both devices and voice assistant software. As ... during the past few years, multiple health-related voice assistants have been introduced, including ...
(Date:1/3/2020)... ... ... Stay on top of current hot topics through free webinars presented by leading ... free, so be sure to register today to save your place. Participate in the ... our upcoming webinars: , CLINICAL OPERATIONS , January 23 – The Benefits of a ...
Breaking Medicine Technology:
Cached News: