Specialized natural killer cells in human tonsils pack a punch

Mar 12, 2008

Tonsils are a source of sore throats and an excuse for ice cream. But they also provide an important protective service, their immune-cell-rich tissue acting as the body’s first defense against the germs about to be swallowed or inhaled. Researchers have known that tonsils are packed with B cells, which flag invaders for other cells to attack. But a new study by Rockefeller University scientists shows that tonsils also house a different, very specialized cell that helps protect against the Epstein Barr virus (EBV).

EBV is a member of the herpes virus family and can cause a variety of ailments, from infectious mononucleosis to cancers such as Burkitt’s lymphoma. It acts by working its way into B cells and transforming them into virus-infected cells that continuously multiply. Some people manage to control the virus with no symptoms whatsoever, while others succumb. New research published in PLoS Pathogens may help explain why.

In comparison to peripheral blood, the tonsils contain just a small number of natural killer cells, immune cells named for their ability to recognize something as foreign and destroy it. But Christian Münz, head of the Laboratory of Viral Immunobiology, and Ph.D. student Till Strowig have found that the majority of the tonsils’ natural killer cells are a specific kind, called CD56bright cells, and incredibly potent — nearly a hundred times better at preventing EBV from transforming B cells than natural killer cells located in peripheral blood. “These cells are not only enriched in this organ, but they are better than at any other site,” Münz says.

In fact, the researchers found that the location of this protective subset of natural killer cells is quite precise, poised at a germ-entry site where they can control incoming pathogens. And surprisingly, the CD56bright cells have something in common with a totally different class of immune cells: Like T cells, they must be activated before they can do their job. This discovery paves the way for future EBV vaccine research, as prompting the activating cells could lead to a higher degree of viral resistance by the natural killer cells. Because there’s not yet a mouse model for the virus, Münz, Strowig and postdoc Cagan Gurer are now working to create mice with human immune system components, allowing the mice to be infected with EBV and allowing the researchers to watch what happens during the early stages of infection — stages during which humans have no symptoms, and have therefore never been studied.

“It might allow us, for the first time, to look at very early immune responses to Epstein Barr virus,” Münz says. “And it could hopefully be developed to test different vaccine formulations that might make the mice resistant against developing virus-induced tumors.” For developing nations, where Burkitt’s lymphoma is too costly to treat once it develops, a vaccine that efficiently controls Epstein Barr virus would be invaluable.

Citation: PLoS Pathogens 4(2):e27 (February 8, 2008)

Source: Rockefeller University

Explore further: Growing a blood vessel in a week

add to favorites email to friend print save as pdf

Related Stories

Russia turns back clocks to permanent Winter Time

8 hours ago

Russia on Sunday is set to turn back its clocks to winter time permanently in a move backed by President Vladimir Putin, reversing a three-year experiment with non-stop summer time that proved highly unpopular.

UN climate talks shuffle to a close in Bonn

8 hours ago

Concern was high at a perceived lack of urgency as UN climate negotiations shuffled towards a close in Bonn on Saturday with just 14 months left to finalise a new, global pact.

Microsoft beefs up security protection in Windows 10

12 hours ago

What Microsoft users in business care deeply about—-a system architecture that supports efforts to get their work done efficiently; a work-centric menu to quickly access projects rather than weather readings ...

New iPad cellular models have Apple SIM flexibility

Oct 19, 2014

Cellular-enabled iPad models are under a new paradigm, said AppleInsider, regarding the Apple SIM. Apple's newest iPad models with cellular connectivity use a SIM card which tech sites said could eventually ...

Comet Siding Spring whizzes past Mars (Update)

Oct 19, 2014

A comet the size of a small mountain and about as solid as a pile of talcum powder whizzed past Mars on Sunday, dazzling space enthusiasts with the once-in-a-million-years encounter.

Recommended for you

Growing a blood vessel in a week

Oct 24, 2014

The technology for creating new tissues from stem cells has taken a giant leap forward. Three tablespoons of blood are all that is needed to grow a brand new blood vessel in just seven days. This is shown ...

Testing time for stem cells

Oct 24, 2014

DefiniGEN is one of the first commercial opportunities to arise from Cambridge's expertise in stem cell research. Here, we look at some of the fundamental research that enables it to supply liver and pancreatic ...

Team finds key signaling pathway in cause of preeclampsia

Oct 23, 2014

A team of researchers led by a Wayne State University School of Medicine associate professor of obstetrics and gynecology has published findings that provide novel insight into the cause of preeclampsia, the leading cause ...

Rapid test to diagnose severe sepsis

Oct 23, 2014

A new test, developed by University of British Columbia researchers, could help physicians predict within an hour if a patient will develop severe sepsis so they can begin treatment immediately.

User comments : 0