Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Firefly light illuminates course of herpes infection in mice

05.11.2002


Researchers are using a herpes virus that produces a firefly enzyme to illuminate the virus’s course of infection in mice and to help monitor the infection’s response to therapy. The work is published by scientists at Washington University School of Medicine in St. Louis in the December issue of the Journal of Virology.



"This study demonstrates the feasibility of monitoring microbial infections in living animals in real time," says study leader David A. Leib, Ph.D., associate professor of ophthalmology and visual sciences and of molecular microbiology. "The technique enables us to follow an infection over time as it progresses and resolves, and we can do this repeatedly using the same animal."

This technology may solve several problems in studying herpes infections and the genes that control them. To investigate the progress of an infection over a course of days, for example, researchers normally must sacrifice infected mice each day and analyze their tissues to determine the level of virus present. The process is further complicated by the fact that individual mice respond differently to infection.


"One must make a leap of faith that a mouse sacrificed on day three of an infection is responding to the virus in the same way as a mouse sacrificed on day two of the infection," says Leib.

This new technology, an imaging method known as in vivo bioluminescence, enables investigators to track changes in the viral population in the same animal day after day. The device is located in the Molecular Imaging Center at the University’s Mallinckrodt Institute of Radiology.

"This technology can be used to explore questions about this virus that are possible only by studying entire living animals over time," says Gary D. Luker, M.D., an assistant professor of radiology with the Molecular Imaging Center and first author of the paper.

"This is an excellent example of the unique information and new collaborations that are generated when we examine fundamental biological processes with molecular imaging tools," says David Piwnica-Worms, M.D., Ph.D., professor of radiology and of molecular biology and pharmacology and director of the Molecular Imaging Center.

The investigators first added a gene for luciferase, an enzyme produced by fireflies, to a strain of herpes simplex type 1 virus. After determining that the modified virus behaves in cells like the normal virus, they injected the modified virus into several locations in mice, including the brain and abdominal cavity.

Daily for nine days, the mice were injected with luciferin, a compound also produced by fireflies that emits light when exposed to luciferase. They then were anesthetized, placed in a light-free box and photographed using a charged-coupled device, or CCD camera. The camera captures light emitted through the tissues of the mouse by the actively replicating virus. The image produced by the camera shows the location and amount of virus in a mouse as areas of color, ranging from blue (low levels) to red (high levels), superimposed on a photograph of the anesthetized animal. Light produced by the luciferase-luciferin reaction is known as bioluminescence because it is generated by biological chemicals.

This imaging method enabled the investigators to monitor the infection as it spread and receded over nine days. In a second experiment, mice infected with the modified virus were treated with the antiviral drug valacyclovir. The investigators found that decreases in bioluminescence correlated with the decline in the amount of virus present.

The method works in part because bioluminescence produced by fireflies contains a significant amount of red light, which penetrates tissues more effectively than other wavelengths of light. This effect can be seen by shining a flashlight through a finger; it is red light that penetrates the finger.

The investigators next will use the imaging technique to study the course of herpes infection in mice lacking certain elements of the immune system to determine how different elements of the immune system influence the course of an infection.


Luker GD, Bardill JP, Prior JL, Pica CM, Piwnica-Worms D, Leib DA. Noninvasive bioluminescence imaging of Herpes simplex virus type 1 infection and therapy in living mice. Journal of Virology, 76(23), 12149-12161, Dec. 2002.

Funding from the National Institutes of Health, Research to Prevent Blindness and a Robert E. McCormick Scholarship supported this research.

Darrell E. Ward | EurekAlert!
Further information:
http://medinfo.wustl.edu/

More articles from Health and Medicine:

nachricht Study suggests possible new target for treating and preventing Alzheimer's
02.12.2016 | Oregon Health & Science University

nachricht The first analysis of Ewing's sarcoma methyloma opens doors to new treatments
01.12.2016 | IDIBELL-Bellvitge Biomedical Research Institute

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: Novel silicon etching technique crafts 3-D gradient refractive index micro-optics

A multi-institutional research collaboration has created a novel approach for fabricating three-dimensional micro-optics through the shape-defined formation of porous silicon (PSi), with broad impacts in integrated optoelectronics, imaging, and photovoltaics.

Working with colleagues at Stanford and The Dow Chemical Company, researchers at the University of Illinois at Urbana-Champaign fabricated 3-D birefringent...

Im Focus: Quantum Particles Form Droplets

In experiments with magnetic atoms conducted at extremely low temperatures, scientists have demonstrated a unique phase of matter: The atoms form a new type of quantum liquid or quantum droplet state. These so called quantum droplets may preserve their form in absence of external confinement because of quantum effects. The joint team of experimental physicists from Innsbruck and theoretical physicists from Hannover report on their findings in the journal Physical Review X.

“Our Quantum droplets are in the gas phase but they still drop like a rock,” explains experimental physicist Francesca Ferlaino when talking about the...

Im Focus: MADMAX: Max Planck Institute for Physics takes up axion research

The Max Planck Institute for Physics (MPP) is opening up a new research field. A workshop from November 21 - 22, 2016 will mark the start of activities for an innovative axion experiment. Axions are still only purely hypothetical particles. Their detection could solve two fundamental problems in particle physics: What dark matter consists of and why it has not yet been possible to directly observe a CP violation for the strong interaction.

The “MADMAX” project is the MPP’s commitment to axion research. Axions are so far only a theoretical prediction and are difficult to detect: on the one hand,...

Im Focus: Molecules change shape when wet

Broadband rotational spectroscopy unravels structural reshaping of isolated molecules in the gas phase to accommodate water

In two recent publications in the Journal of Chemical Physics and in the Journal of Physical Chemistry Letters, researchers around Melanie Schnell from the Max...

Im Focus: Fraunhofer ISE Develops Highly Compact, High Frequency DC/DC Converter for Aviation

The efficiency of power electronic systems is not solely dependent on electrical efficiency but also on weight, for example, in mobile systems. When the weight of relevant components and devices in airplanes, for instance, is reduced, fuel savings can be achieved and correspondingly greenhouse gas emissions decreased. New materials and components based on gallium nitride (GaN) can help to reduce weight and increase the efficiency. With these new materials, power electronic switches can be operated at higher switching frequency, resulting in higher power density and lower material costs.

Researchers at the Fraunhofer Institute for Solar Energy Systems ISE together with partners have investigated how these materials can be used to make power...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

ICTM Conference 2017: Production technology for turbomachine manufacturing of the future

16.11.2016 | Event News

Innovation Day Laser Technology – Laser Additive Manufacturing

01.11.2016 | Event News

#IC2S2: When Social Science meets Computer Science - GESIS will host the IC2S2 conference 2017

14.10.2016 | Event News

 
Latest News

UTSA study describes new minimally invasive device to treat cancer and other illnesses

02.12.2016 | Medical Engineering

Plasma-zapping process could yield trans fat-free soybean oil product

02.12.2016 | Agricultural and Forestry Science

What do Netflix, Google and planetary systems have in common?

02.12.2016 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>