Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Two molecules work together to aid transport of immune cells, UT Southwestern researchers find

21.04.2004


New research findings about T-cell transport shed light on how the normal immune system functions and could have implications in fighting autoimmune and inflammatory diseases, say researchers at UT Southwestern Medical Center at Dallas.



Two molecules on the surfaces of T-cells – a type of immune cell – must work in tandem to help the T-cells cross from the bloodstream into infected tissues, where the T-cells initiate an immune or inflammatory response, researchers at UT Southwestern have discovered.

The research, which was done in mice, appears in the April 21 issue of the journal Immunity.


In order to fight certain infections, T-cells must migrate from the bloodstream and into infected tissue. T-cells also cross blood vessel walls to initiate inflammatory or autoimmune responses in diseases such as rheumatoid arthritis, type 1 diabetes, lupus, asthma, Crohn’s disease and colitis.

Scientists know that two specific molecules, or receptors, on passing T-cells in the bloodstream interact with receptors on the walls of blood vessels. One T-cell receptor, called CD44, is responsible for getting the T-cells to "roll" along the blood vessel wall.

"CD44 governs the rolling behavior of the T-cell, where it touches and then lifts off the vascular wall," said Dr. Mark Siegelman, associate professor of pathology at UT Southwestern and senior author of the study.

A second receptor, VLA-4, stops the T-cells from rolling. This step in the process is called firm adhesion.

"You need both of these steps in order to get the T-cells out of the blood vessel and into tissue," Dr. Siegelman said. "Only by completing the second step, firm adhesion, has the T-cell committed to sticking and getting out."

In the new research, UT Southwestern scientists found that in order to get the T-cells to stick firmly to the vascular wall, the CD44 and VLA-4 receptors on the T-cell had to be physically linked. If they do not form what’s called a bimolecular complex, firm adhesion does not occur.

"Our findings define a relationship between CD44 and VLA-4 that results in a cooperative system," Dr. Siegelman said. "If they aren’t linked, the T-cells exhibit rolling behavior, but not firm adhesion, and, therefore, they don’t move through the blood vessel wall to initiate immune or inflammatory responses."

The researchers also found that if part of the CD44 receptor is missing, the bimolecular complex does not form, inhibiting the T-cells from moving out of the bloodstream.

The research results may aid in future development of treatments for rheumatoid arthritis, for example, a condition in which T-cells travel from the bloodstream and into the space between joints, causing painful inflammation.

"One strategy for drug development might be to target CD44 or this bimolecular complex in order to prevent T-cells from getting in there and starting an inflammatory response," Dr. Siegelman said.

Other UT Southwestern researchers involved with the study are Dr. Animesh Nandi, research scientist in biochemistry, and Dr. Pila Estess, assistant professor of pathology.


The research was funded in part by the National Institutes of Health and the Burroughs Wellcome Fund.

Amanda Siegfried | EurekAlert!
Further information:
http://www.swmed.edu/

More articles from Life Sciences:

nachricht How brains surrender to sleep
23.06.2017 | IMP - Forschungsinstitut für Molekulare Pathologie GmbH

nachricht A new technique isolates neuronal activity during memory consolidation
22.06.2017 | Spanish National Research Council (CSIC)

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Can we see monkeys from space? Emerging technologies to map biodiversity

An international team of scientists has proposed a new multi-disciplinary approach in which an array of new technologies will allow us to map biodiversity and the risks that wildlife is facing at the scale of whole landscapes. The findings are published in Nature Ecology and Evolution. This international research is led by the Kunming Institute of Zoology from China, University of East Anglia, University of Leicester and the Leibniz Institute for Zoo and Wildlife Research.

Using a combination of satellite and ground data, the team proposes that it is now possible to map biodiversity with an accuracy that has not been previously...

Im Focus: Climate satellite: Tracking methane with robust laser technology

Heatwaves in the Arctic, longer periods of vegetation in Europe, severe floods in West Africa – starting in 2021, scientists want to explore the emissions of the greenhouse gas methane with the German-French satellite MERLIN. This is made possible by a new robust laser system of the Fraunhofer Institute for Laser Technology ILT in Aachen, which achieves unprecedented measurement accuracy.

Methane is primarily the result of the decomposition of organic matter. The gas has a 25 times greater warming potential than carbon dioxide, but is not as...

Im Focus: How protons move through a fuel cell

Hydrogen is regarded as the energy source of the future: It is produced with solar power and can be used to generate heat and electricity in fuel cells. Empa researchers have now succeeded in decoding the movement of hydrogen ions in crystals – a key step towards more efficient energy conversion in the hydrogen industry of tomorrow.

As charge carriers, electrons and ions play the leading role in electrochemical energy storage devices and converters such as batteries and fuel cells. Proton...

Im Focus: A unique data centre for cosmological simulations

Scientists from the Excellence Cluster Universe at the Ludwig-Maximilians-Universität Munich have establised "Cosmowebportal", a unique data centre for cosmological simulations located at the Leibniz Supercomputing Centre (LRZ) of the Bavarian Academy of Sciences. The complete results of a series of large hydrodynamical cosmological simulations are available, with data volumes typically exceeding several hundred terabytes. Scientists worldwide can interactively explore these complex simulations via a web interface and directly access the results.

With current telescopes, scientists can observe our Universe’s galaxies and galaxy clusters and their distribution along an invisible cosmic web. From the...

Im Focus: Scientists develop molecular thermometer for contactless measurement using infrared light

Temperature measurements possible even on the smallest scale / Molecular ruby for use in material sciences, biology, and medicine

Chemists at Johannes Gutenberg University Mainz (JGU) in cooperation with researchers of the German Federal Institute for Materials Research and Testing (BAM)...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Plants are networkers

19.06.2017 | Event News

Digital Survival Training for Executives

13.06.2017 | Event News

Global Learning Council Summit 2017

13.06.2017 | Event News

 
Latest News

Quantum thermometer or optical refrigerator?

23.06.2017 | Physics and Astronomy

A 100-year-old physics problem has been solved at EPFL

23.06.2017 | Physics and Astronomy

Equipping form with function

23.06.2017 | Information Technology

VideoLinks
B2B-VideoLinks
More VideoLinks >>>