Researchers find the often-discarded tissue is a “factory” for immune cells
(COLUMBUS, Ohio) – If you or your children still have your tonsils, you may want to hang on to them, if at all possible. For the first time, researchers have discovered that your tonsils perform a task that wasn’t suspected before, they could be an important source of immune cells known as T-cells.¹
“T-cells are critical in our body’s defense against things like infection and cancer,” said Dr. Michael Caligiuiri, CEO, Ohio State’s James Cancer Hospital and Solove Research Institute and Director of the OSU Comprehensive Cancer Center. “We’ve been able to show, quite conclusively, that the tonsils are a ‘factory’ for these T-cells.”
They are called “T-cells” because they originate and mature in the thymus gland, which sits on the heart. It was believed that the thymus was the only source for these immune cells, until now.
Working with graduate fellow Susan McClory, Caligiuri and his team analyzed tonsil tissue obtained from children undergoing routine tonsillectomy at Nationwide Children’s Hospital in Columbus. “We had a clue from some earlier work that a cell that wasn’t supposed to be in the tonsils, actually may have lived there,” said Dr. Caligiuri. “It turns out it was the T-cell.”
The discovery could mean the potential for research and possibly new treatments for autoimmune diseases like rheumatoid arthritis or like cancers that are caused by viruses. It could also cause doctors to pause before taking tonsils out.
For generations, having tonsils removed was somewhat of a rite of passage for children in the U.S. At the height of popularity around 1960, a tonsillectomy was performed every 30 seconds in this country, accounting for more than a million surgeries per year.²
“If you were old enough and still had tonsils, they used to take them out just because they thought they should come out,” said Dr. Arick Forrest, vice chairman of the Department of Otolaryngology at The Ohio State University’s Wexner Medical Center. “But because of new evidence from research, we’re now trying to leave them in as long as possible.”
Today the number of tonsillectomies in children under the age of 15 has been cut in half³ and could fall further with this most recent discovery, especially considering work that has already been done with T-cells in the lab.
“We have shown, when it comes to cancers caused by viruses, like lymphoma or sarcoma,” said Dr. Caligiuri, “that you can take someone’s T-cells out, rev them up against that virus in the test tube, put them back in, and it can cure the cancer.”
Knowing that there is another source for those cells outside of the thymus, could prove vital.
Still, tonsillectomies won’t completely disappear. “In some cases, they are absolutely necessary,” said Dr. Forrest. In some patients tonsils can become so enlarged that they impair breathing and disrupt sleep, and in the case of a tonsil abscess, they can be life-threatening.
Also, if tonsils become chronically infected, “they no longer help you fight other infections, because the tonsils are so busy just taking care of the infection they have within themselves,” said Dr. Forrest. “In those cases, a tonsillectomy can really improve the quality of somebody’s life, if it’s done for the right reasons.”
Next, researchers hope to learn what proportion of T-cells come from the tonsils compared to the thymus, and what role each plays in immune function.
“We have more work to do,” said Dr. Caligiuri, “but this discovery has shown us that there is another source for T-cells, and that could prove to be very important for research into a lot of different diseases.”
¹ Evidence for a stepwise program of extrathymic T cell development within the human tonsil. The Journal of Clinical Investigation. Online: http://www.jci.org/articles/view/46125
² Health Statistics from the US National Health Survey, Hospital Discharges and length of stay: short-stay hospital, 1958-1960 (Page 38). Centers for Disease Control and Prevention.Online: http://www.cdc.gov/nchs/data/public_health/SeriesB_32.pdf
³ National Health Statistics Report, Number 11. Ambulatory Surgery in the United States, Rev. 2009 (Page 16). Centers for Disease Control and Prevention. Online: http://www.cdc.gov/nchs/data/nhsr/nhsr011.pdf