Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Genomics-based vaccine could prevent deadly cattle disease

14.02.2006


Every year, East Coast fever destroys the small farmer’s dream of escaping poverty in Africa. Killing more than a million cattle and costing some $200 million annually, this tick-borne disease rages across a dozen countries in eastern and central Africa. Now, an international team of scientists has taken the first major step toward a vaccine to prevent East Coast fever. Their work, published in the February 13-17 early online edition of the Proceedings of the National Academy of Sciences, shows how genomics can generate pivotal new vaccines.



In the study, scientists from five institutions, including The Institute for Genomic Research (TIGR), identify five vaccine targets, or candidate proteins that could form the basis for an East Coast fever subunit vaccine. Based on combined bioinformatics analyses and lab tests, these proteins appear to provide a protective immune response to the disease. "This initiative took just three years, after many years of scientists trying other methods," remarks Vishvanath Nene, a study author and molecular biologist at TIGR. "It’s a huge jump forward."

To make the jump, researchers used the genome sequence of the parasite responsible for East Coast fever. A tick-borne parasite, Theileria parva, causes the disease. When ticks infected with T. parva bite cattle, they transmit the parasite, launching the disease that typically kills cattle within a month. In July, 2005, TIGR led a research team that published T. parva’s genome sequence, representing roughly 4,000 genes, in Science.


In the current study, Nene, along with Malcolm Gardner and Claire Fraser-Liggett, also of TIGR, relied on known biology to search T. parva’s genome for potential vaccine proteins. First, scientists know that immunity to the parasite, and thus East Coast fever, emerges from immune system cells known as killer T cells. Second, they know that T. parva is an intracellular pathogen--it infects and secretes proteins inside cattle white blood cells, which become malignant. The white blood cell then unwittingly passes small fragments of the secreted parasitic proteins associated with a certain type if its own proteins along to its cell surface. And this is where a vaccine could come in: A vaccine made of the T. parva proteins found on the surface of host cells should trigger an immune response in cattle. Vaccinated cattle would then be protected from the parasite.

To find potential vaccine antigens, the TIGR researchers scanned T. parva’s entire genome for genes that make secreted proteins. In particular, they searched for genes that make a "secretion signal," a telltale peptide sequence found at the start of secreted proteins. Sure enough, the scientists found some 400 T. parva genes containing the secretion signal. This set of genes provided a starting pool of candidate proteins. Based on further tests, the study’s research team, led by the International Livestock Research Institute (ILRI) of Nairobi, Kenya, cloned 55 candidate antigen genes and screened those genes for response by killer T cells taken from cattle immune to East Coast fever. To complement TIGR’s gene selection strategy, ILRI also incorporated a random screen of T. parva DNA for vaccine candidates.

In total, the team found five candidate vaccine antigens. In lab tests, these antigens triggered a response from cattle immune killer T cells. Going a further step further, the scientists inoculated cattle with these antigens and then gave the cattle a potentially lethal dose of T. parva. When compared with control animals, vaccinated cattle showed significantly stronger immune response to the parasite.

"This study is a true milestone," says Fraser-Liggett, president of TIGR. "It’s one of the first to take advantage of genomic technologies and build a test vaccine using immune killer T cells as a screening reagent." In addition to TIGR and ILRI, the research team included scientists from: the Ludwig Institute for Cancer Research in Brussels; the Wellcome Trust Center for Human Genetics in Oxford; Sanofi Pasteur in Toronto; the University of Edinburgh; and Merial SAS, an international animal health company. ILRI and Merial have partnered to develop a vaccine against East Coast fever.

By using genomics to understand and fight T. parva, scientists may make advances against related parasites that cause malaria, tuberculosis, and other diseases in which killer T cells also play a role in immunity. What’s more, because T. parva launches a cancer-like illness inside the white blood cells of cattle, it may provide a model system for understanding the mechanics of cancer biology.

But for Nene, who was born in Kenya and worked at ILRI for 15 years before coming to TIGR in 2001, the march against East Coast fever is significant reward, itself. "This disease takes an enormous toll on the local society and economy of rural areas across eastern and central Africa, including Maasai and other pastoral communities," he says.

In particular, East Coast fever kills cattle kept by families trying to rise out of poverty. If researchers are successful, Nene notes, the entire region will have new reason to hope for a better life. Evans Taracha, ILRI project leader, also highlights the importance of strategic research partnerships to overcome this and similar diseases.

Kathryn Brown | EurekAlert!
Further information:
http://www.tigr.org/

More articles from Life Sciences:

nachricht Nanoparticle Exposure Can Awaken Dormant Viruses in the Lungs
16.01.2017 | Helmholtz Zentrum München - Deutsches Forschungszentrum für Gesundheit und Umwelt

nachricht Cholera bacteria infect more effectively with a simple twist of shape
13.01.2017 | Princeton University

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Designing Architecture with Solar Building Envelopes

Among the general public, solar thermal energy is currently associated with dark blue, rectangular collectors on building roofs. Technologies are needed for aesthetically high quality architecture which offer the architect more room for manoeuvre when it comes to low- and plus-energy buildings. With the “ArKol” project, researchers at Fraunhofer ISE together with partners are currently developing two façade collectors for solar thermal energy generation, which permit a high degree of design flexibility: a strip collector for opaque façade sections and a solar thermal blind for transparent sections. The current state of the two developments will be presented at the BAU 2017 trade fair.

As part of the “ArKol – development of architecturally highly integrated façade collectors with heat pipes” project, Fraunhofer ISE together with its partners...

Im Focus: How to inflate a hardened concrete shell with a weight of 80 t

At TU Wien, an alternative for resource intensive formwork for the construction of concrete domes was developed. It is now used in a test dome for the Austrian Federal Railways Infrastructure (ÖBB Infrastruktur).

Concrete shells are efficient structures, but not very resource efficient. The formwork for the construction of concrete domes alone requires a high amount of...

Im Focus: Bacterial Pac Man molecule snaps at sugar

Many pathogens use certain sugar compounds from their host to help conceal themselves against the immune system. Scientists at the University of Bonn have now, in cooperation with researchers at the University of York in the United Kingdom, analyzed the dynamics of a bacterial molecule that is involved in this process. They demonstrate that the protein grabs onto the sugar molecule with a Pac Man-like chewing motion and holds it until it can be used. Their results could help design therapeutics that could make the protein poorer at grabbing and holding and hence compromise the pathogen in the host. The study has now been published in “Biophysical Journal”.

The cells of the mouth, nose and intestinal mucosa produce large quantities of a chemical called sialic acid. Many bacteria possess a special transport system...

Im Focus: Newly proposed reference datasets improve weather satellite data quality

UMD, NOAA collaboration demonstrates suitability of in-orbit datasets for weather satellite calibration

"Traffic and weather, together on the hour!" blasts your local radio station, while your smartphone knows the weather halfway across the world. A network of...

Im Focus: Repairing defects in fiber-reinforced plastics more efficiently

Fiber-reinforced plastics (FRP) are frequently used in the aeronautic and automobile industry. However, the repair of workpieces made of these composite materials is often less profitable than exchanging the part. In order to increase the lifetime of FRP parts and to make them more eco-efficient, the Laser Zentrum Hannover e.V. (LZH) and the Apodius GmbH want to combine a new measuring device for fiber layer orientation with an innovative laser-based repair process.

Defects in FRP pieces may be production or operation-related. Whether or not repair is cost-effective depends on the geometry of the defective area, the tools...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

12V, 48V, high-voltage – trends in E/E automotive architecture

10.01.2017 | Event News

2nd Conference on Non-Textual Information on 10 and 11 May 2017 in Hannover

09.01.2017 | Event News

Nothing will happen without batteries making it happen!

05.01.2017 | Event News

 
Latest News

Multiregional brain on a chip

16.01.2017 | Power and Electrical Engineering

New technology enables 5-D imaging in live animals, humans

16.01.2017 | Information Technology

Researchers develop environmentally friendly soy air filter

16.01.2017 | Power and Electrical Engineering

VideoLinks
B2B-VideoLinks
More VideoLinks >>>