Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Researchers Identify How Yersinia Spreads Within Infected Organs

18.09.2013
Extension of technique improves the study of bacteria in organs

Researchers at Tufts University School of Medicine and the Sackler School of Graduate Biomedical Sciences at Tufts have identified how one type of bacteria, Yersinia, immobilizes the immune system in order to grow in the organs of mice.

To do so, the researchers extended the use of a technique and suggest that it could be used to study other bacteria that use the same or similar means of infection. The study is published in the September 11 issue of Cell Host & Microbe.

Led by microbiologist Joan Mecsas, the research team studied a specific member of a family of effector proteins known as Yops. Like other effector proteins, Yops alter the immune system to make it possible for bacteria such as Yersinia to spread in infected organs and from organ to organ. The research team studied the Yop known as YopH in order to identify its specific effect within infected spleens.

Many bacteria inject proteins into cells in organs as a part of their infection process. The technique they used, called the TEM-1 reporter system, uses an enzyme and a dye to color-code cells. This enables researchers to see which of the many cells in an organ have been injected. The current study used the TEM system to identify injected cells but then, in an interesting first, gathered these cells from infected organs to study them further.

After isolating the color-coded cells from infected organs, the researchers determined how immune cells are made inactive by effector proteins, such as YopH and other Yops, by comparing cells with and without the specific effector protein. The research team used tissue samples from two sets of mice with Yersinia pseudotuberculosis: those with and without functional YopH proteins. They separated tissue cells from immune cells taken from spleens and compared suspended immune cells from the two sets of mice.

The researchers determined that YopH deactivates multiple proteins and blocks calcium flows vital to normal immune cell communication. Decreased immune cell communication allows Yersinia to continue spreading in infected organs without an effective response from the immune system.

“Being able to pull out and study cells from infected tissues that contain bacterial proteins enabled us to see the effects of YopH in tissues infected with Yersinia pseudotuberculosis. Our application of this technique may also work in bacteria similar to Yersinia, to understand how other bacteria cause damage in organ systems,” said senior author Joan Mecsas, Ph.D., an associate professor of molecular biology and microbiology at Tufts University School of Medicine and member of the immunology and molecular microbiology programs at the Sackler School of Graduate Biomedical Sciences at Tufts.

“We know that two forms of food poisoning and some forms of pneumonias caused by E. coli, Salmonella, and Pseudomonas respectively, as well as other types of infections depend on the same system as Yersinia to infect humans and animals. There are also several bacteria that use related means to infect people and animals. This includes the bacteria that cause Legionnaires’ disease, ulcers, cholera, various foodborne illnesses, pneumonias and even general infections such as some ear and sinus infections. This technique could be applied to understand these other bacteria,” said co-first author Enrique Durand, Ph.D., a graduate of the molecular microbiology program at the Sackler School, now teaching biology in the International Baccalaureate (honors) program at Snowden International School at Copley in the Boston Public Schools system.

“Yersinia and bacteria with systems of infection like Yersinia can have drastic effects on organs, including inflammation that leads to appendicitis-like pain. Seeing the effect of the bacteria on specific cell types within organs, such as the spleen, has been challenging because cells grown in petri dishes cannot mimic the holistic environment of a mammalian system,” said co-first author Hortensia Rolan, Ph.D., a postdoctoral scholar in the Mecsas lab.

Researchers have studied Yersinia since the discovery of the most well-known member of the Yersinia genus, Yersinia pestis, which causes bubonic plague (and which was found in squirrels in a national forest in Los Angeles County this summer). But Yersinia pseudotuberculosis, its near relative, is a standard Yersinia bacterium to study in labs.

Yersinia pseudotuberculosis, which is not related to tuberculosis, is a type of zoonotic bacteria, or one that can be transferred from an animal to a person. Infections in humans are rare and, like bubonic plague, it can be treated with antibiotics.

Research reported in this publication was supported by the National Institute of Allergies and Infectious Diseases of the National Institutes of Health under award numbers T32AI007329, T32AI007422, and R01AI056068.

Rolan, H.G., Durand, E.A., Mecsas, J. (September 11, 2013). Identifying Yersinia YopH-targeted signal transduction pathways that impair neutrophil responses during in vivo murine infection. Cell Host & Microbe (14:3, pp. 306-317). DOI: 10.1016/j.chom.2013.08.013

About Tufts University School of Medicine and the Sackler School of Graduate Biomedical Sciences

Tufts University School of Medicine and the Sackler School of Graduate Biomedical Sciences at Tufts University are international leaders in innovative medical education and advanced research. The School of Medicine and the Sackler School are renowned for excellence in education in general medicine, biomedical sciences, special combined degree programs in business, health management, public health, bioengineering and international relations, as well as basic and clinical research at the cellular and molecular level. Ranked among the top in the nation, the School of Medicine is affiliated with six major teaching hospitals and more than 30 health care facilities. Tufts University School of Medicine and the Sackler School undertake research that is consistently rated among the highest in the nation for its effect on the advancement of medical science.

If you are a member of the media interested in learning more about this topic, or speaking with a faculty member at Tufts University School of Medicine or another Tufts health sciences researcher, please contact Siobhan Gallagher at 617-636-6586.

Siobhan E. Gallagher | Newswise
Further information:
http://www.tufts.edu

More articles from Life Sciences:

nachricht Flow of cerebrospinal fluid regulates neural stem cell division
22.05.2018 | Helmholtz Zentrum München - Deutsches Forschungszentrum für Gesundheit und Umwelt

nachricht Chemists at FAU successfully demonstrate imine hydrogenation with inexpensive main group metal
22.05.2018 | Friedrich-Alexander-Universität Erlangen-Nürnberg

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Explanation for puzzling quantum oscillations has been found

So-called quantum many-body scars allow quantum systems to stay out of equilibrium much longer, explaining experiment | Study published in Nature Physics

Recently, researchers from Harvard and MIT succeeded in trapping a record 53 atoms and individually controlling their quantum state, realizing what is called a...

Im Focus: Dozens of binaries from Milky Way's globular clusters could be detectable by LISA

Next-generation gravitational wave detector in space will complement LIGO on Earth

The historic first detection of gravitational waves from colliding black holes far outside our galaxy opened a new window to understanding the universe. A...

Im Focus: Entangled atoms shine in unison

A team led by Austrian experimental physicist Rainer Blatt has succeeded in characterizing the quantum entanglement of two spatially separated atoms by observing their light emission. This fundamental demonstration could lead to the development of highly sensitive optical gradiometers for the precise measurement of the gravitational field or the earth's magnetic field.

The age of quantum technology has long been heralded. Decades of research into the quantum world have led to the development of methods that make it possible...

Im Focus: Computer-Designed Customized Regenerative Heart Valves

Cardiovascular tissue engineering aims to treat heart disease with prostheses that grow and regenerate. Now, researchers from the University of Zurich, the Technical University Eindhoven and the Charité Berlin have successfully implanted regenerative heart valves, designed with the aid of computer simulations, into sheep for the first time.

Producing living tissue or organs based on human cells is one of the main research fields in regenerative medicine. Tissue engineering, which involves growing...

Im Focus: Light-induced superconductivity under high pressure

A team of scientists of the Max Planck Institute for the Structure and Dynamics of Matter (MPSD) at the Center for Free-Electron Laser Science in Hamburg investigated optically-induced superconductivity in the alkali-doped fulleride K3C60under high external pressures. This study allowed, on one hand, to uniquely assess the nature of the transient state as a superconducting phase. In addition, it unveiled the possibility to induce superconductivity in K3C60 at temperatures far above the -170 degrees Celsius hypothesized previously, and rather all the way to room temperature. The paper by Cantaluppi et al has been published in Nature Physics.

Unlike ordinary metals, superconductors have the unique capability of transporting electrical currents without any loss. Nowadays, their technological...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Save the date: Forum European Neuroscience – 07-11 July 2018 in Berlin, Germany

02.05.2018 | Event News

Invitation to the upcoming "Current Topics in Bioinformatics: Big Data in Genomics and Medicine"

13.04.2018 | Event News

Unique scope of UV LED technologies and applications presented in Berlin: ICULTA-2018

12.04.2018 | Event News

 
Latest News

Supersonic waves may help electronics beat the heat

18.05.2018 | Power and Electrical Engineering

Keeping a Close Eye on Ice Loss

18.05.2018 | Information Technology

CrowdWater: An App for Flood Research

18.05.2018 | Information Technology

VideoLinks
Science & Research
Overview of more VideoLinks >>>