Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Protective gene may enhance vaccine responses

16.08.2004


Researchers from the University of Chicago have discovered the first of a new class of "protective factors" that appear to be required for the development of memory T cells, the cells that form the core of a vaccine response. The finding could help scientists create more effective vaccines and may lead to potent immune system-based therapies against diseases that have previously eluded vaccines, such as cancer or AIDS.



When the immune system detects an invader, such as a virus, T cells with an affinity for that particular invader multiply rapidly, attack and eliminate infected cells. Once the infection is cleared, however, 90 to 95 percent of those T cells die off, a process called contraction. The five percent or so that survive are known as memory T cells. If a similar infection recurs, these experienced warriors are prepared to rush to the site, recognize that invader and eradicate it again.

Scientists know a great deal about the rapid proliferation and differentiation of these T cells but very little about the factors that regulate contraction. In the September, 2004, issue of Nature Immunology – published on-line August 15 -- the researchers show that activation of the gene for the Serine protease inhibitor 2A (Spi2A) can prevent the death of T cells during the contraction phase, resulting in about five times as many memory T cells.


"Drugs based on protective factors such as Spi2A could provide an enormous boost to vaccines," said study author Philip Ashton-Rickardt, professor of pathology and a member of the committee on immunology at the University of Chicago. "This could allow us to extend the duration of an immune response against chronic infections or to focus the power of the immune system on tumor cells, targets that have thus far been quite elusive."

The researchers began by screening approximately 11,000 genes from mouse T cells, to find the small number of genes that were more active in the T cells that survived the contraction phase after exposure to a virus. Then they focused on the likely candidates, genes that interfered with the processes that trigger cell death. Their search led them to Spi2A.

Spi2A, they found, was produced in higher amounts in memory T cells. It suppressed cathepsin B, a potent digestive enzyme that can induce cell death. T cell populations in which Spi2A levels were reduced produced fewer memory cells. As a consequence, mice with low Spi2A levels produced a severely diminished response to the virus when exposed to it a second time.

On the other hand, mice with elevated Spi2A produced up to five times the normal number of memory T cells. When faced with the virus a second time, these memory T cells produced an overwhelming response, completely eradicating the infection within hours.

"Spi2A appears to play a crucial role in regulating contraction," Ashton-Rickardt said. "Increasing Spi2A levels alone can increase the survival of memory T cells from the standard 5 to 10 percent up to about 40 percent.

His lab has already begun to test small molecules that mimic the effects of Spi2A and could be given along with a vaccine.

This finding may also provide clues about how to reverse the process, suggesting ways to reduce or eliminate memory T cells responsible the unwanted immune responses that cause autoimmune diseases such as arthritis.

Additional authors of the paper include Ni Lui, Tiphanie Phillips, Minling Zhang, Yue Wang, Joseph Opferman and Ramila Shah, all from the University of Chicago. The National Institutes of Health funded the study.

John Easton | EurekAlert!
Further information:
http://www.uchospitals.edu

More articles from Health and Medicine:

nachricht Antibiotic effective against drug-resistant bacteria in pediatric skin infections
17.02.2017 | University of California - San Diego

nachricht Tiny magnetic implant offers new drug delivery method
14.02.2017 | University of British Columbia

All articles from Health and Medicine >>>

The most recent press releases about innovation >>>

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

Im Focus: Breakthrough with a chain of gold atoms

In the field of nanoscience, an international team of physicists with participants from Konstanz has achieved a breakthrough in understanding heat transport

In the field of nanoscience, an international team of physicists with participants from Konstanz has achieved a breakthrough in understanding heat transport

Im Focus: DNA repair: a new letter in the cell alphabet

Results reveal how discoveries may be hidden in scientific “blind spots”

Cells need to repair damaged DNA in our genes to prevent the development of cancer and other diseases. Our cells therefore activate and send “repair-proteins”...

Im Focus: Dresdner scientists print tomorrow’s world

The Fraunhofer IWS Dresden and Technische Universität Dresden inaugurated their jointly operated Center for Additive Manufacturing Dresden (AMCD) with a festive ceremony on February 7, 2017. Scientists from various disciplines perform research on materials, additive manufacturing processes and innovative technologies, which build up components in a layer by layer process. This technology opens up new horizons for component design and combinations of functions. For example during fabrication, electrical conductors and sensors are already able to be additively manufactured into components. They provide information about stress conditions of a product during operation.

The 3D-printing technology, or additive manufacturing as it is often called, has long made the step out of scientific research laboratories into industrial...

Im Focus: Mimicking nature's cellular architectures via 3-D printing

Research offers new level of control over the structure of 3-D printed materials

Nature does amazing things with limited design materials. Grass, for example, can support its own weight, resist strong wind loads, and recover after being...

Im Focus: Three Magnetic States for Each Hole

Nanometer-scale magnetic perforated grids could create new possibilities for computing. Together with international colleagues, scientists from the Helmholtz Zentrum Dresden-Rossendorf (HZDR) have shown how a cobalt grid can be reliably programmed at room temperature. In addition they discovered that for every hole ("antidot") three magnetic states can be configured. The results have been published in the journal "Scientific Reports".

Physicist Dr. Rantej Bali from the HZDR, together with scientists from Singapore and Australia, designed a special grid structure in a thin layer of cobalt in...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Booth and panel discussion – The Lindau Nobel Laureate Meetings at the AAAS 2017 Annual Meeting

13.02.2017 | Event News

Complex Loading versus Hidden Reserves

10.02.2017 | Event News

International Conference on Crystal Growth in Freiburg

09.02.2017 | Event News

 
Latest News

Biocompatible 3-D tracking system has potential to improve robot-assisted surgery

17.02.2017 | Medical Engineering

Real-time MRI analysis powered by supercomputers

17.02.2017 | Medical Engineering

Antibiotic effective against drug-resistant bacteria in pediatric skin infections

17.02.2017 | Health and Medicine

VideoLinks
B2B-VideoLinks
More VideoLinks >>>