Gene against bacterial attack unravelled

Oct 28, 2008

Dutch researcher Joost Wiersinga from AMC Medical Center in Amsterdam has unravelled a genetic defense mechanism against the lethal bacteria Burkholderia pseudomallei. The research is the next step towards a vaccine against this bacterium suitable for bioweapons.

Humans have an innate defence system against deadly bacteria. However, how the step from gene to anti-bacterial effect occurs in the body is not yet known. To date, B. Pseudomallei, a bacterium suitable for bioweapons, had managed to elude medics. It can remain hidden in the human body for many years without being detected by the immune system. The bacteria can suddenly become activated and spread throughout the body, resulting in the patient dying from blood poisoning. AMC physician Joost Wiersinga and the Laboratory for Experimental Internal Medicine discovered which gene-protein combination renders the lethal bacteria B. pseudomallei harmless.

Wiersinga focussed on the so-called Toll-like receptors. These are the proteins that initiate the fight against pathogens. There are currently ten known Toll-like receptors which are located on the outside of immune cells, our body's defence system. The toll-like receptors jointly function as a 10-figure alarm code. Upon coming into contact with the immune cell each bacterium enters its own Toll code. For known pathogens this sets off an alarm in the immune system and the defence mechanism is activated. Yet B. pseudomallei fools the system by entering the code of a harmless bacterium. As a result the body's defence system remains on standby.

Yet some people are resistant: they become infected but not ill. Wiersinga found a genetic cause for this resistance. He discovered which toll receptor can fend off B. pseudomallei. He did this by rearing mice DNA in which the gene for Toll2 production was switched on and off. 'The group where the gene for Toll2 was switched off, survived the bacterial infection', says Wiersinga. 'The other receptor that we investigated, Toll4, had no effect - even though for the past ten years medics had regarded this as the most important receptor.' The ultimate aim of this study is to develop a vaccine.

Source: Netherlands Organization for Scientific Research

Explore further: Scottish zoo: 'Bad news' for pregnant giant panda

add to favorites email to friend print save as pdf

Related Stories

We are all made of stars

39 minutes ago

Astronomers spend most of their time contemplating the universe, quite comfortable in the knowledge that we are just a speck among billions of planets, stars and galaxies. But last week, the Australian astronomical ...

Netflix unveils new way to share recommendations

40 minutes ago

Netflix is giving its Internet video subscribers a more discreet way to recommend movies and TV shows to their Facebook friends after realizing most people don't want to share their viewing habits with large audiences.

How bubble studies benefit science and engineering

41 minutes ago

The image above shows a perfect bubble imploding in weightlessness. This bubble, and many like it, are produced by the researchers from the École Polytechnique Fédérale de Lausanne in Switzerland. What ...

How financial decisions are made

29 minutes ago

Jayant Kale didn't grow up dreaming of becoming a leading expert in corporate finance and mutual fund investment. But he's happy he invested in that market early in life.

Recommended for you

Research helps identify memory molecules

46 minutes ago

A newly discovered method of identifying the creation of proteins in the body could lead to new insights into how learning and memories are impaired in Alzheimer's disease.

Sorghum and biodiversity

57 minutes ago

It is difficult to distinguish the human impact on the effects of natural factors on the evolution of crop plants. A Franco-Kenyan research team has managed to do just that for sorghum, one of the main cereals ...

Robotics to combat slimy pest

59 minutes ago

One hundred years after they arrived in a sack of grain, white Italian snails are the target of beleaguered South Australian farmers who have joined forces with University of Sydney robotics experts to eradicate ...

User comments : 0