Trojan horse bacteria use nanobodies to conquer sleeping sickness

Feb 14, 2012

Sleeping sickness, caused by the trypanosome Trypanosoma brucei, is transmitted to humans (and animals) via the bite of the tsetse fly. New research published in BioMed Central's open access journal Microbial Cell Factories uses a bacteria, which naturally lives in the fly, to release nanobodies (antibody fragments) against the trypanosome. These antibodies, which bind to the surface of the parasite, are the first stage in producing targeted nanobodies which could kill, or block, trypanosome development.

Sleeping sickness threatens millions of lives across sub-Saharan Africa. The first stage (haemolymphatic phase) of infection causes fever, headaches, aching joints and itching. The second stage (neurological phase), when the parasite crosses the , results in confusion, poor co-ordination and the which give the disease its name. Without treatment is fatal. However diagnosis and treatment are difficult and require specially trained staff. Trypanosome infection in cattle causes anemia and weight loss, which can lead to death of the anima. Together these have a serious impact on public health and agricultural development across Africa.

The bacterium (Sodalis glossinidius) is an endosymbiont, similar to the 'good bacteria' which populate human intestines, found in tsetse fly midgut, muscle, fat and salivary glands. They are passed from a mother to her offspring - consequently genetically modified bacteria should be spread down generations of flies once females are released into the wild. Researchers from Belgium genetically altered S. glossinidius bacteria so that they secreted a single domain antibody against a variant surface glycoprotein (VSG) of T. brucei. The growth of the mutated bacteria was unaltered, increasing their chances of survival once released.

Prof Van Den Abbeele, from the Institute of Tropical Medicine, Antwerp, explained, "When we looked at living under conditions that mimic the inside of the tsetse gut the Sodalis-expressed nanobodies were biologically active and bound all over the surface of the parasite. Now that we know this technique works we are looking at making nanobodies which will destroy or block development of the parasite in the tsetse fly gut."

The most recent epidemic occurred in 1970 and, despite continued efforts and falling numbers of new cases in that last decade, this disease has not yet gone away. This new technology provides hope against a devastating disease.

Explore further: Team publishes evidence for natural alternative to antibiotic use in livestock

More information: Expression and extracellular release of a functional anti-trypanosome Nanobody(R) in Sodalis glossinidius, a bacterial symbiont of the tsetse fly. Linda De Vooght, Guy Caljon, Benoit Stijlemans, Patrick De Beatselier, Marc Coosemans and Jan Van Den Abbeele. Microbial Cell Factories (in press)

add to favorites email to friend print save as pdf

Related Stories

Fly gut bacteria could control sleeping sickness

May 11, 2010

A new bacterial species, found in the gut of the fly that transmits African sleeping sickness, could be engineered to kill the parasite that causes the disease. The study, published in the International Journal of Systematic an ...

Recommended for you

Researchers capture picture of microRNA in action

Oct 30, 2014

Biologists at The Scripps Research Institute (TSRI) have described the atomic-level workings of "microRNA" molecules, which control the expression of genes in all animals and plants.

Blocking a fork in the road to DNA replication

Oct 30, 2014

A team of Whitehead Institute scientists has discovered the surprising manner in which an enigmatic protein known as SUUR acts to control gene copy number during DNA replication. It's a finding that could shed new light on ...

Cell division, minus the cells

Oct 30, 2014

(Phys.org) —The process of cell division is central to life. The last stage, when two daughter cells split from each other, has fascinated scientists since the dawn of cell biology in the Victorian era. ...

A new method simplifies the analysis of RNA structure

Oct 30, 2014

To understand the function of an RNA molecule, similar to the better-known DNA and vital for cell metabolism, we need to know its three-dimensional structure. Unfortunately, establishing the shape of an RNA ...

User comments : 0

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.