Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

T cell immunity enhanced by timing of interleukin-7 therapy

05.02.2008
That the cell nurturing growth factor interleukin-7 can help ramp up the ability of the immune system to remember the pathogenic villains it encounters is well known.

But precisely how this natural protein works its magic on the cells of the immune system is not well understood. Now, however, in research that may have implications for developing vaccines against HIV and cancer, a team of scientists from the University of Wisconsin-Madison has found that the timing of interleuin-7 therapy is critical for increasing the number of killer cells that zero in on and destroy virus-infected cells.

Writing in the current online issue (Feb. 1, 2008) of the Journal of Clinical Investigation, a team led by UW-Madison School of Veterinary Medicine Professor of pathobiological sciences Marulasiddappa Suresh reports that therapeutic administration of interleukin-7 can be linked to a stage of early infection to effectively increase the number of a type of killer cell that recognizes and selectively assassinates virus-infected cells.

"These cells need to get interleukin-7 for their survival," explains Suresh, of the killer immune cell known as CD8 T cells, a type of white blood cell that attacks virus-infected cells, foreign cells and cancer cells. Interleukin-7 is produced in very small amounts in bone marrow, spleen, and the thymus, but scientists have been able to isolate and synthesize the agent, which is now in pre-clinical testing for a variety of conditions.

"This is one of the most exciting cytokines in pre-clinical human trials," says Suresh. "The idea is that it might be used as an immune restorative agent. It is absolutely essential for normal development and functioning of the immune system."

Effectively stimulating the immune system -- the complex of organs and cells that defends the body against infection and disease -- is a grail of biomedical science in the fight against infectious diseases.

Suresh explains that upon infection, the body unleashes an army of T cells to fight infected or rogue cells. But when the body perceives an infection may be contained, the number of T cells it deploys is dramatically reduced. However, a certain number of T cells, known as memory cells and that are capable of recognizing a recently vanquished foe, remain. Stimulating memory T and B cells is the basis of vaccination, but vaccines often do not induce a sufficient number of memory CD8 T cells.

Interleukin-7 is a well-studied growth factor that is known to help generate and maintain the immune system's “memory” CD8 T cells, which have the ability to remember the identity of its targets, such as cancer cells or cells that have been taken over by a virus. A paucity of interleukin-7 is believed to limit the survival and persistence of memoryCD8 T cells.

Despite the promise of interleukin-7 as a means to bolster immunity, an optimal treatment regimen has yet to be determined.

In studies in mice, Suresh and his colleagues found that T cell memory is best enhanced when interleukin-7 is administered during a phase of infection when the number of T cells is ramping down.

In the new Wisconsin study, Suresh's group gave interleukin-7 to mice during different stages of a viral infection. They found that by administering interleukin-7 when the number of T cells is in decline, it is possible to increase the number of memory CD8 T cells that remain to stand guard and protect against re-infection.

"The purpose of the immune response is to expand these cells," says Suresh, explaining that T cells act like serial killers, snuffing one infected cell after another until the viral infection is controlled.

During the expansion phase of infection, when the body is generating the most T cells, administration of interleukin-7 seems to have no effect, according to Suresh. But during the contraction phase, memory is increased.

"We tried this in a DNA vaccine and it works," says Suresh. "Even with the weakest vaccine, we could increase the memory cells and improve protection against infection. What this shows is that the number of memory cells are not predetermined. You can increase them and interleukin-7 drives their proliferation."

Marulasiddappa Suresh | EurekAlert!
Further information:
http://www.vetmed.wisc.edu

Further reports about: CD8 Infection Suresh T cells Vaccine immune system interleukin-7

More articles from Life Sciences:

nachricht Turning carbon dioxide into liquid fuel
06.08.2020 | DOE/Argonne National Laboratory

nachricht Tellurium makes the difference
06.08.2020 | Friedrich-Schiller-Universität Jena

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: ScanCut project completed: laser cutting enables more intricate plug connector designs

Scientists at the Fraunhofer Institute for Laser Technology ILT have come up with a striking new addition to contact stamping technologies in the ERDF research project ScanCut. In collaboration with industry partners from North Rhine-Westphalia, the Aachen-based team of researchers developed a hybrid manufacturing process for the laser cutting of thin-walled metal strips. This new process makes it possible to fabricate even the tiniest details of contact parts in an eco-friendly, high-precision and efficient manner.

Plug connectors are tiny and, at first glance, unremarkable – yet modern vehicles would be unable to function without them. Several thousand plug connectors...

Im Focus: New Strategy Against Osteoporosis

An international research team has found a new approach that may be able to reduce bone loss in osteoporosis and maintain bone health.

Osteoporosis is the most common age-related bone disease which affects hundreds of millions of individuals worldwide. It is estimated that one in three women...

Im Focus: AI & single-cell genomics

New software predicts cell fate

Traditional single-cell sequencing methods help to reveal insights about cellular differences and functions - but they do this with static snapshots only...

Im Focus: TU Graz Researchers synthesize nanoparticles tailored for special applications

“Core-shell” clusters pave the way for new efficient nanomaterials that make catalysts, magnetic and laser sensors or measuring devices for detecting electromagnetic radiation more efficient.

Whether in innovative high-tech materials, more powerful computer chips, pharmaceuticals or in the field of renewable energies, nanoparticles – smallest...

Im Focus: Tailored light inspired by nature

An international research team with Prof. Cornelia Denz from the Institute of Applied Physics at the University of Münster develop for the first time light fields using caustics that do not change during propagation. With the new method, the physicists cleverly exploit light structures that can be seen in rainbows or when light is transmitted through drinking glasses.

Modern applications as high resolution microsopy or micro- or nanoscale material processing require customized laser beams that do not change during...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

“Conference on Laser Polishing – LaP 2020”: The final touches for surfaces

23.07.2020 | Event News

Conference radar for cybersecurity

21.07.2020 | Event News

Contact Tracing Apps against COVID-19: German National Academy Leopoldina hosts international virtual panel discussion

07.07.2020 | Event News

 
Latest News

Rare Earth Elements in Norwegian Fjords?

06.08.2020 | Earth Sciences

Anode material for safe batteries with a long cycle life

06.08.2020 | Power and Electrical Engineering

Turning carbon dioxide into liquid fuel

06.08.2020 | Life Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>