Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Lock to food-borne pathogen pathway may be key to vaccine

02.02.2004


A previously unidentified protein on the surface of intestinal cells is giving Purdue University researchers clues on how to prevent disease


A computer monitor in Arun Bhunia’s research lab displays a Listeria monocytogenes adhering to human intestinal cells. Research conducted by Bhunia, a professor of food science at Purdue, and Jennifer Wampler, a postdoctoral student, led to the discovery of the protein on the surface of intestinal cells that allows a food-borne pathogen to attach to the intestine. (Purdue Agricultural Communications photo/Tom Campbell)



The scientists believe their results eventually could lead to a way to prevent food-borne Listeria monocytogenes infection, which has a 20 percent fatality rate, as well as other diseases. The study of the bacteria is reported in the February issue of the journal Infection and Immunity.

"This research reveals a detailed mechanism that allows interaction of Listeria with a cell-surface protein, or receptor, on intestinal cells," said Arun Bhunia, a Department of Food Science microbiologist. "Knowing the entryway into the cell will allow us in the future to develop a method to prevent that interaction."


Jennifer Wampler, a postdoctoral student and lead author of the study, said, "Listeria often is implicated in patients with weakened immune systems, so we think that this research could also give us clues as to how other diseases work. This receptor is not unique for Listeria, so it also could be used by other organisms to take advantage and get inside a host cell to cause disease."

Bacteria have proteins, called ligands, that bind with a protein molecule, or receptor, on cells in the body, which is like placing a key in a lock. This interaction opens the door that leads to a complicated series of biochemical reactions. These reactions allow the pathogen to enter cells, in this case in the intestine, and then move on into the liver, spleen, brain or placenta, causing illness and possibly death.

Listeria is responsible for about 2,500 recorded food-borne illnesses annually in the United States and is the deadliest food-borne disease, according to the Centers for Disease Control and Prevention. It is especially dangerous for pregnant women, the elderly and those with immuno-comprised diseases such as HIV. The infection can cause meningitis, brain-stem encephalitis and spontaneous abortion.

The Purdue team placed a Listeria protein known to bind with human host cells in a laboratory dish with human intestinal cells. They found that the bacteria’s ligand bound with an intestinal cell surface protein, which they identified as heat shock protein 60 (Hsp60).

Heat shock proteins are found in most cells. They are called chaperone proteins because they help other proteins stay organized when cells face any type of stress. Until recently, it was believed these proteins were only found in the mitochondria, the cells’ engines.

Now that researchers know that these proteins also are found on cell surfaces and act as receptors, they will begin investigating how to control the infection process.

In the study published in Infection and Immunity, the Purdue researchers used an anti-Hsp60 antibody, a built-in disease-fighting antibody that reduced Listeria’s ability to bind with intestinal cells by 74 percent

"If interaction of these two molecules is the beginning of the infection’s intestinal phase pathway that leads to illness, then we need to block them," Bhunia said. "Our focus now is to determine when and under what conditions the bacterium moves from intestinal cells into the system.

"If we understand the mechanism of how bacteria interacts with cells before causing damage and producing systemic illness, this may allow us to formulate a vaccination strategy to prevent the infection."

The Purdue researchers plan to study whether the Hsp60 is more abundant in the intestine and also in people most at risk for Listeria-caused food-borne disease, such as pregnant women or HIV patients, Wampler said. They also want to study what other diseases might use this or a similar pathway to enter the body.

Other researchers on this study were Kwang-Pyo Kim, a doctoral student, and Ziad Jaradat, a former postdoctoral student.

Bhunia also is a researcher in the Purdue Center for Food Safety Engineering, a collaboration among the university’s schools of Agriculture, Consumer and Family Sciences, Engineering, Veterinary Medicine and the U.S. Department of Agriculture-Agricultural Research Service.

Writer: Susan A. Steeves, (765) 496-7481, ssteeves@purdue.edu

Source: Arun Bhunia, (765) 494-5443, bhunia@purdue.edu

Ag Communications: (765) 494-2722; Beth Forbes, bforbes@aes.purdue.edu
Agriculture News Page

Susan A. Steeves | Purdue News
Further information:
http://news.uns.purdue.edu/html4ever/2004/040130.Bhunia.listeria.html
http://www.ars.usda.gov/

More articles from Health and Medicine:

nachricht Inselspital: Fewer CT scans needed after cerebral bleeding
20.03.2019 | Universitätsspital Bern

nachricht Building blocks for new medications: the University of Graz is seeking a technology partner
19.03.2019 | Karl-Franzens-Universität Graz

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: Magnetic micro-boats

Nano- and microtechnology are promising candidates not only for medical applications such as drug delivery but also for the creation of little robots or flexible integrated sensors. Scientists from the Max Planck Institute for Polymer Research (MPI-P) have created magnetic microparticles, with a newly developed method, that could pave the way for building micro-motors or guiding drugs in the human body to a target, like a tumor. The preparation of such structures as well as their remote-control can be regulated using magnetic fields and therefore can find application in an array of domains.

The magnetic properties of a material control how this material responds to the presence of a magnetic field. Iron oxide is the main component of rust but also...

Im Focus: Self-healing coating made of corn starch makes small scratches disappear through heat

Due to the special arrangement of its molecules, a new coating made of corn starch is able to repair small scratches by itself through heat: The cross-linking via ring-shaped molecules makes the material mobile, so that it compensates for the scratches and these disappear again.

Superficial micro-scratches on the car body or on other high-gloss surfaces are harmless, but annoying. Especially in the luxury segment such surfaces are...

Im Focus: Stellar cartography

The Potsdam Echelle Polarimetric and Spectroscopic Instrument (PEPSI) at the Large Binocular Telescope (LBT) in Arizona released its first image of the surface magnetic field of another star. In a paper in the European journal Astronomy & Astrophysics, the PEPSI team presents a Zeeman- Doppler-Image of the surface of the magnetically active star II Pegasi.

A special technique allows astronomers to resolve the surfaces of faraway stars. Those are otherwise only seen as point sources, even in the largest telescopes...

Im Focus: Heading towards a tsunami of light

Researchers at Chalmers University of Technology and the University of Gothenburg, Sweden, have proposed a way to create a completely new source of radiation. Ultra-intense light pulses consist of the motion of a single wave and can be described as a tsunami of light. The strong wave can be used to study interactions between matter and light in a unique way. Their research is now published in the scientific journal Physical Review Letters.

"This source of radiation lets us look at reality through a new angle - it is like twisting a mirror and discovering something completely different," says...

Im Focus: Revealing the secret of the vacuum for the first time

New research group at the University of Jena combines theory and experiment to demonstrate for the first time certain physical processes in a quantum vacuum

For most people, a vacuum is an empty space. Quantum physics, on the other hand, assumes that even in this lowest-energy state, particles and antiparticles...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

International Modelica Conference with 330 visitors from 21 countries at OTH Regensburg

11.03.2019 | Event News

Selection Completed: 580 Young Scientists from 88 Countries at the Lindau Nobel Laureate Meeting

01.03.2019 | Event News

LightMAT 2019 – 3rd International Conference on Light Materials – Science and Technology

28.02.2019 | Event News

 
Latest News

To proliferate or not to proliferate

21.03.2019 | Life Sciences

Magnetic micro-boats

21.03.2019 | Physics and Astronomy

Motorless pumps and self-regulating valves made from ultrathin film

21.03.2019 | HANNOVER MESSE

VideoLinks
Science & Research
Overview of more VideoLinks >>>