Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Researchers identify protein that regulates killer cells

21.06.2002


Researchers at the University of Toronto and Mount Sinai Hospital have identified a protein that plays a critical role in the regulation of "natural killers cells" in the immune system’s battle against foreign and diseased cells.



"Our research is a small part of the larger problem of how viruses and diseased cells ravage the body and circumvent our immune system," says Kathleen Binns, a U of T doctoral student in medical genetics and microbiology and an author on a paper in the June 20 issue of Science.

Using mass spectrometry, Binns, who does research in the Samuel Lunenfeld Research Institute at Mount Sinai and MDS Sciex, sequenced and identified a mystery protein from co-researchers at the Swiss Federal Institute of Technology in Switzerland.


Once identified, the protein (SSPase) was sent back to the Swiss researchers where they cloned its gene and sequenced its DNA. That gene, they discovered, is a key component involved in regulation of "natural killer cells" - cells produced by the body’s immune system that attack foreign or mutated cells like caused by viruses or cancer.

"This research gives us a better understanding of how the immune system works. As a result, we have a better understanding of how viruses and cancer try to get around this process. One day, we will hopefully be able to develop treatments and therapies to counter these rogue cells," says Binns.

A group of genes called the major histocompatibility complex I (MHC-I) are a natural part of the immune system and present in most cells in the body, explains Binns. Acting like an information relay, the MHC-I molecules retrieve bits and pieces of the proteins from inside the cell and display them on the cell surface. "MHC complexes essentially give a read out of what’s inside the cell," she says.

T-cells, one of the main components of the immune system, "examine" the protein fragments on the cell surface and if they recognize them, the T-cells move on. If, however, the T-cells do not recognize the fragments, the cell may be hosting a virus or manufacturing mutant proteins (as in the case of cancer). The T-cells then react by attacking and killing the "diseased" cells.

Some virus and tumor cells, however, have evolved mechanisms that circumvent the T-cell attack by stopping MHC production and the display of disease proteins, says Binns.

As a countermeasure, the researchers found that the immune system developed a monitor that employs the SSPase protein and uses a second type of immune cell known as a natural killer cell, she notes. The protein processes MHC-I molecules to make a peptide signal. If sufficient levels of the MHC-I protein are present in the cell, the natural killer cell moves on. If, however, the killer cell detects insufficient levels of the MHC-I protein because it has not received the particular peptide signal, the killer cell attacks and destroys the suspect cell.

"This process is a check on viruses and abnormal cells that try to bypass the T-cell system," says Binns. "Viruses become smarter, our immune systems work to counteract them and the viruses get smarter again. There’s this constant evolution for the drive to survive, and viruses and cancer cells have the same drive to survive that we do."

Binns conducted the research with Andreas Weihofen, lead author on the study, Marius Lemberg and Bruno Martoglio of the Institute of Biochemistry at the Swiss Federal Institute of Technology, and Keith Ashman, an investigator at the Samuel Lunenfeld Research Institute at Mount Sinai Hospital.

This research was funded by the Natural Science and Engineering Research Council of Canada and MDS Sciex, the Swiss Federal Institute of Technology and the Swiss National Science Foundation.


CONTACT:

Kathleen Binns
Department of Medical Genetics and Microbiology
416-586-4524
binns@mshri.on.ca

Janet Wong
U of T Public Affairs
416-978-5949
jf.wong@utoronto.ca




Janet Wong | EurekAlert!

More articles from Life Sciences:

nachricht Microscope measures muscle weakness
16.11.2018 | Friedrich-Alexander-Universität Erlangen-Nürnberg

nachricht Good preparation is half the digestion
16.11.2018 | Max-Planck-Institut für Stoffwechselforschung

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: UNH scientists help provide first-ever views of elusive energy explosion

Researchers at the University of New Hampshire have captured a difficult-to-view singular event involving "magnetic reconnection"--the process by which sparse particles and energy around Earth collide producing a quick but mighty explosion--in the Earth's magnetotail, the magnetic environment that trails behind the planet.

Magnetic reconnection has remained a bit of a mystery to scientists. They know it exists and have documented the effects that the energy explosions can...

Im Focus: A Chip with Blood Vessels

Biochips have been developed at TU Wien (Vienna), on which tissue can be produced and examined. This allows supplying the tissue with different substances in a very controlled way.

Cultivating human cells in the Petri dish is not a big challenge today. Producing artificial tissue, however, permeated by fine blood vessels, is a much more...

Im Focus: A Leap Into Quantum Technology

Faster and secure data communication: This is the goal of a new joint project involving physicists from the University of Würzburg. The German Federal Ministry of Education and Research funds the project with 14.8 million euro.

In our digital world data security and secure communication are becoming more and more important. Quantum communication is a promising approach to achieve...

Im Focus: Research icebreaker Polarstern begins the Antarctic season

What does it look like below the ice shelf of the calved massive iceberg A68?

On Saturday, 10 November 2018, the research icebreaker Polarstern will leave its homeport of Bremerhaven, bound for Cape Town, South Africa.

Im Focus: Penn engineers develop ultrathin, ultralight 'nanocardboard'

When choosing materials to make something, trade-offs need to be made between a host of properties, such as thickness, stiffness and weight. Depending on the application in question, finding just the right balance is the difference between success and failure

Now, a team of Penn Engineers has demonstrated a new material they call "nanocardboard," an ultrathin equivalent of corrugated paper cardboard. A square...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

“3rd Conference on Laser Polishing – LaP 2018” Attracts International Experts and Users

09.11.2018 | Event News

On the brain’s ability to find the right direction

06.11.2018 | Event News

European Space Talks: Weltraumschrott – eine Gefahr für die Gesellschaft?

23.10.2018 | Event News

 
Latest News

Purdue cancer identity technology makes it easier to find a tumor's 'address'

16.11.2018 | Health and Medicine

Good preparation is half the digestion

16.11.2018 | Life Sciences

Microscope measures muscle weakness

16.11.2018 | Life Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>