Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Insight on fruit fly immune system could lead to new types of vaccines

12.03.2007
The tiny fruit fly has a lot to teach humans. Researchers at the Stanford University School of Medicine have found for the first time that flies' primitive immune systems may develop long-term protection from infection, an ability previously thought impossible for insects.

The findings could have implications for new ways of developing human vaccines, especially for people with compromised immune systems.

The evidence that a fruit fly's immune response can adapt to - or retain memory of - an earlier infection contradicts the long-held dogma that immune memory cannot exist in invertebrates such as insects. Such memory of a specific pathogen, known as adaptation, is supposed to be a hallmark of the higher-level immune system response of humans and other vertebrates.

The Stanford work raises the possibility that humans could make use of this rudimentary immune response if their higher-level system is crippled. "It's a springboard to looking at the immune system in a whole new way," said David Schneider, PhD, assistant professor of microbiology and immunology and senior author of the study, which will be published in the March 9 issue of Public Library of Science-Pathogens.

... more about:
»Adaptation »Adaptive »Pham »Vaccine »innate

One of the two arms of the immune response in higher organisms is similar to that of flies. This arm is known as innate immunity, and it is thought to be a primitive first-line, nonspecific response to a pathogen "invader." The other arm found in higher organisms is adaptive immunity, which has a memory that retains an internal record of contact with an invader and - employing T and B cells - springs into action once it encounters the same invader again. This adaptive immunity explains why a vaccine provides protection.

"AIDS patients are like fruit flies in the sense that they don't have properly functioning T cells," said Schneider. "If there is anything we could do to make their remaining innate immunity better through adaptation, that would be really helpful."

Harnessing the potential power of adaptation in the innate immune system might also be a boon in the body's defense against bioterrorism or disease pandemics. "The B and T cells of the adaptive immune system take a long time to react," said Schneider. "But you might be able to speed things up if you could snort something up your nose that would make your innate immune system ready to fight."

While inviting novel ways of thinking about future vaccines and treating AIDS patients, the new finding immediately stirs up the field of insect immunology. Existing publications about the fruit fly's immune system explicitly state that it has no memory, and no ability to make specific long-term changes prompted by its exposure to pathogens. Because immune memory was defined as nonexistent, no one ever did the experiment to question whether the fly's immune system could adapt.

Then graduate student Linh Pham arrived in Schneider's lab. She was interested in pushing the boundaries of the assumptions of the innate immune system's limitations.

In the past decade or so, work done on fruit fly immunology has always been done on a fly infected only once - and that's not how things happen outside a lab, where a fly would be continually exposed to microbes. Pham thought to ask what happens when the flies encounter a microbe a second time.

Pham found a bacterium - Streptococcus pneumoniae - that infected the flies but didn't kill all of them. "I liken my work to the first vaccination experiments," said Pham, who is first author of the study. She essentially vaccinated over a million flies, typically doing 7,000 in a day, in numerous experiments. In a key experiment, she injected some flies with killed bacteria and others with just saline solution. She waited a week, then reinjected both groups with what should have been a lethal dose of live bacteria. Then she calculated the percentage of how many survived, compared with the flies that been injected only with saline.

"I didn't think the results would be so clean-cut," she said. Within two days, the second dose killed almost all of the flies that had initially received just saline solution. Those that had been vaccinated lived just as long - about one month - as a separate group that had not been infected.

To ensure it wasn't a fluke of the bacterium she chose, she tested other organisms. She identified a fungus that infects fruit flies in the wild, Beauveria bassiana, that elicited a similar protective effect. "It was really easy to show the adaptation part," she added. "Getting to the mechanism was the complicated part."

In the study, the researchers conclude that a much-studied receptor called Toll is involved, as are other processes. Pham is now teasing apart the finer aspects of how the fruit fly protects itself against S. pneumoniae.

Schneider and Pham said they hope their work encourages the search for a similar adaptive response in the innate immune systems of humans or other vertebrates. "One of the things that I thought was really cool about this work is that it might be a way to develop a vaccine that modulates the innate immune system," said Pham. "Of course, we are cautious about hoping for this."

Mitzi Baker | EurekAlert!
Further information:
http://www.stanford.edu

Further reports about: Adaptation Adaptive Pham Vaccine innate

More articles from Life Sciences:

nachricht Water forms 'spine of hydration' around DNA, group finds
26.05.2017 | Cornell University

nachricht How herpesviruses win the footrace against the immune system
26.05.2017 | Helmholtz-Zentrum für Infektionsforschung

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 the immune system be boosted against Staphylococcus aureus by delivery of messenger RNA?

Staphylococcus aureus is a feared pathogen (MRSA, multi-resistant S. aureus) due to frequent resistances against many antibiotics, especially in hospital infections. Researchers at the Paul-Ehrlich-Institut have identified immunological processes that prevent a successful immune response directed against the pathogenic agent. The delivery of bacterial proteins with RNA adjuvant or messenger RNA (mRNA) into immune cells allows the re-direction of the immune response towards an active defense against S. aureus. This could be of significant importance for the development of an effective vaccine. PLOS Pathogens has published these research results online on 25 May 2017.

Staphylococcus aureus (S. aureus) is a bacterium that colonizes by far more than half of the skin and the mucosa of adults, usually without causing infections....

Im Focus: A quantum walk of photons

Physicists from the University of Würzburg are capable of generating identical looking single light particles at the push of a button. Two new studies now demonstrate the potential this method holds.

The quantum computer has fuelled the imagination of scientists for decades: It is based on fundamentally different phenomena than a conventional computer....

Im Focus: Turmoil in sluggish electrons’ existence

An international team of physicists has monitored the scattering behaviour of electrons in a non-conducting material in real-time. Their insights could be beneficial for radiotherapy.

We can refer to electrons in non-conducting materials as ‘sluggish’. Typically, they remain fixed in a location, deep inside an atomic composite. It is hence...

Im Focus: Wafer-thin Magnetic Materials Developed for Future Quantum Technologies

Two-dimensional magnetic structures are regarded as a promising material for new types of data storage, since the magnetic properties of individual molecular building blocks can be investigated and modified. For the first time, researchers have now produced a wafer-thin ferrimagnet, in which molecules with different magnetic centers arrange themselves on a gold surface to form a checkerboard pattern. Scientists at the Swiss Nanoscience Institute at the University of Basel and the Paul Scherrer Institute published their findings in the journal Nature Communications.

Ferrimagnets are composed of two centers which are magnetized at different strengths and point in opposing directions. Two-dimensional, quasi-flat ferrimagnets...

Im Focus: World's thinnest hologram paves path to new 3-D world

Nano-hologram paves way for integration of 3-D holography into everyday electronics

An Australian-Chinese research team has created the world's thinnest hologram, paving the way towards the integration of 3D holography into everyday...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Marine Conservation: IASS Contributes to UN Ocean Conference in New York on 5-9 June

24.05.2017 | Event News

AWK Aachen Machine Tool Colloquium 2017: Internet of Production for Agile Enterprises

23.05.2017 | Event News

Dortmund MST Conference presents Individualized Healthcare Solutions with micro and nanotechnology

22.05.2017 | Event News

 
Latest News

How herpesviruses win the footrace against the immune system

26.05.2017 | Life Sciences

Water forms 'spine of hydration' around DNA, group finds

26.05.2017 | Life Sciences

First Juno science results supported by University of Leicester's Jupiter 'forecast'

26.05.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>