Navigation Links
Regulatory T-cells – Protector or Cause of Diseases

Immune system protects the body from infection causing agents. Regulatory T-cells, a part of the immune system, learn in early stages of life itself to recognize// the invaders and defend them. But, researchers have reported that these cells seem to protect certain bacteria, viruses and tumors.

Researchers at the Medical college of Georgia, studied the T-cells in the thymus and their subsequent movement in the body, using a genetically manipulated mice and the technology enabling the detection of antigen receptors. These antigen receptors determine what the T-cells recognize.

They found regulatory T cells learn what to protect while in the thymus and that everything the cells learn may not be good, according to research in the August issue of Immunity.

It is widely believed that regulatory T cells only recognize endogenous body tissue so they can stop T cells that are predisposed to attacking it, says Dr. Leszek Ignatowicz, MCG immunologist and the study’s corresponding author.

By examining receptors on all types of T cells before and after they leave the thymus, researchers found regulatory T cells are very diverse and able to recognize endogenous tissue and invaders, Dr. Ignatowicz says.

Unfortunately, the cells also may not learn to recognize all endogenous tissue which, along with environmental and other factors, can lead to autoimmune disease.

T cell schooling in the thymus peaks in the first six weeks of life in the mouse, which roughly translates to the first 15 years of human life. Those early lessons seem to last a lifetime and the few regulatory cells that develop later will be like the early cells, says Dr. Rafal Pacholczyk, MCG immunologist and lead author.

The findings mean, essentially from the beginning, some people may have regulatory T cells less skilled at keeping the immune system from attacking their bodies and/or too skilled at protecting invaders.

I t also means one day physicians might steer early education of regulatory T cells in the thymus as a way to vaccinate children against diseases such as lupus, arthritis and type 1diabetes. Or, they might add regulatory T cells to improve the mix in people who already have some bad police.

“We need some of the regulatory cells more than others,” says Dr. Ignatowicz. “We probably need more of the ones that recognize autoantigens on the pancreas and we need the ones that recognize tumors to be less frequent.”

The fact that most regulatory T cells in the body come directly from the thymus, not from other circulating T cells, also was previously unknown, Dr. Pacholczyk says. “Where they come from is the main question we wanted to answer,” says Dr. Ignatowicz.

It has been thought that some T cells circulating in the body might make the transformation, possibly because of what they are exposed to in the body. In fact T cells most aggressive at attacking endogenous tissue likely would be among those converting to protective regulatory cells, Dr. Ignatowicz says. “We did not find that does not happen, but it’s not the major mechanism for generating regulatory cells in the body,” Dr. Pacholczyk says.

All T cells are made in the bone marrow then move to the thymus as progenitor cells where they differentiate, upregulating surface receptors, which are molecules that detect different antigens. It’s a brutal process – 95 percent of the cells die in the thymus primarily because they recognize body tissue – that winds down after puberty.

All T cells wear their receptors for life, like signature hats. “We decided to compare receptors on the regulatory cells in the periphery with those in the thymus,” says Dr. Pacholczyk. By analyzing receptors on individual cells, they were able to follow the cells after they left the thymus and see if they changed.

Another key question was how regulatory T cells, which make u p about 5 percent of the total T cell population, can control millions of roaming T cells. They found it was a simple matter of numbers: by wearing many hats, or antigen receptors, regulatory T cells can keep their eyes on a lot of different non-regulatory cells.

“The next question we will ask, which is a hot topic right now, is what antigens trigger receptors on regulatory T cells?” says Dr. Pacholczyk. “What do they recognize? We know now they are coming from the thymus but how they are being generated is still a question. We want to look into the nature of antigens those receptors recognize which will allow us to predict more how they are being developed in the tymus.”


Related medicine news :

1. Tumor Suppressor p53s Contradictory Regulatory System
2. Human Complexity Can Be Attributed To Regulatory Sequence
3. The Lancet Calls For Review Of Regulatory Process Of Drug Trials
4. Medtronic’s Insulin Pump Receives Regulatory Approva
5. GMC Wrestles For Regulatory Powers
6. Regulatory Mechanism for Tumor Suppressor Protein Identified
7. Structure of Iron Regulatory Protein-RNA Complex Solved
8. Ramadoss Vows to Set Up Food Regulatory Body in India
9. Master Regulatory Gene of Epithelial Stem Cells Identified
10. T-cells Developed from Human Embryonic Stem Cells
11. Is Diabetes the Leading Cause of Kidney Failure in India
Post Your Comments:

(Date:11/27/2015)... ... November 27, 2015 , ... Consistent ... sharing, the 2016 Building Better Radiology Marketing Programs meeting will showcase ... Sunday, March 6, 2016, at Caesars Palace in Las Vegas with a pre-conference ...
(Date:11/27/2015)... ... November 27, 2015 , ... The moment ... itself for not only fulfilling the needs of advisers and clients but going ... price and providing top-tier customer service. However, there's always room for improvement, which ...
(Date:11/27/2015)... , ... November 27, 2015 , ... ... largest, most successful and prominent nonprofit healthcare organizations in the country. They have ... with various organizations, and helped advance the healthcare industry as a whole through ...
(Date:11/27/2015)... ... November 27, 2015 , ... Indosoft Inc., ... the incorporation of Asterisk 11 LTS (Long Term Support) into its Q-Suite 5.10 ... brings Q-Suite 5.10 up-to-date with a version of Asterisk that will receive not ...
(Date:11/26/2015)... , ... November 26, 2015 , ... ... real-time eReferral system for diagnostic imaging in the Waterloo region. Using the Ocean ... Nuclear Medicine tests directly from their electronic medical record (EMR) without the need ...
Breaking Medicine News(10 mins):
(Date:11/25/2015)... , Nov. 26, 2015  The total global healthcare industry ... over 2015-2016. Latin America has the ... , (excluding Japan ), is second with ... continues to face increased healthcare expenditure. In 2013-2014, total government ... from 43.5% in 2008-2009 to 41.2% in 2013-2014. In real ...
(Date:11/25/2015)... N.C. , Nov. 25, 2015 ... the planned investment of at least $15.8  Million ... Wilmington, NC . The expansion ... capacity to meet the growing demands of the ... site expansion will provide up to ...
(Date:11/25/2015)... AVIV, Israel , November 25, 2015 ... (NASDAQ: KTOV ) (TASE: KTOV), a biopharmaceutical company ... simultaneous treatment of various clinical conditions, today announced the ... 3,158,900 American Depository Shares ( ADSs ), each representing ... purchase up to 3,158,900 ADSs. The ADSs and warrants ...
Breaking Medicine Technology: