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 Link Discovered between Immune System, Brain Structure and Memory
26.04.2017 | Universität Basel

nachricht Researchers develop eco-friendly, 4-in-1 catalyst
25.04.2017 | Brown 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: Making lightweight construction suitable for series production

More and more automobile companies are focusing on body parts made of carbon fiber reinforced plastics (CFRP). However, manufacturing and repair costs must be further reduced in order to make CFRP more economical in use. Together with the Volkswagen AG and five other partners in the project HolQueSt 3D, the Laser Zentrum Hannover e.V. (LZH) has developed laser processes for the automatic trimming, drilling and repair of three-dimensional components.

Automated manufacturing processes are the basis for ultimately establishing the series production of CFRP components. In the project HolQueSt 3D, the LZH has...

Im Focus: Wonder material? Novel nanotube structure strengthens thin films for flexible electronics

Reflecting the structure of composites found in nature and the ancient world, researchers at the University of Illinois at Urbana-Champaign have synthesized thin carbon nanotube (CNT) textiles that exhibit both high electrical conductivity and a level of toughness that is about fifty times higher than copper films, currently used in electronics.

"The structural robustness of thin metal films has significant importance for the reliable operation of smart skin and flexible electronics including...

Im Focus: Deep inside Galaxy M87

The nearby, giant radio galaxy M87 hosts a supermassive black hole (BH) and is well-known for its bright jet dominating the spectrum over ten orders of magnitude in frequency. Due to its proximity, jet prominence, and the large black hole mass, M87 is the best laboratory for investigating the formation, acceleration, and collimation of relativistic jets. A research team led by Silke Britzen from the Max Planck Institute for Radio Astronomy in Bonn, Germany, has found strong indication for turbulent processes connecting the accretion disk and the jet of that galaxy providing insights into the longstanding problem of the origin of astrophysical jets.

Supermassive black holes form some of the most enigmatic phenomena in astrophysics. Their enormous energy output is supposed to be generated by the...

Im Focus: A Quantum Low Pass for Photons

Physicists in Garching observe novel quantum effect that limits the number of emitted photons.

The probability to find a certain number of photons inside a laser pulse usually corresponds to a classical distribution of independent events, the so-called...

Im Focus: Microprocessors based on a layer of just three atoms

Microprocessors based on atomically thin materials hold the promise of the evolution of traditional processors as well as new applications in the field of flexible electronics. Now, a TU Wien research team led by Thomas Müller has made a breakthrough in this field as part of an ongoing research project.

Two-dimensional materials, or 2D materials for short, are extremely versatile, although – or often more precisely because – they are made up of just one or a...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Expert meeting “Health Business Connect” will connect international medical technology companies

20.04.2017 | Event News

Wenn der Computer das Gehirn austrickst

18.04.2017 | Event News

7th International Conference on Crystalline Silicon Photovoltaics in Freiburg on April 3-5, 2017

03.04.2017 | Event News

 
Latest News

Millions through license revenues

27.04.2017 | Health and Medicine

The TU Ilmenau develops tomorrow’s chip technology today

27.04.2017 | Information Technology

Scientist invents way to trigger artificial photosynthesis to clean air

26.04.2017 | Materials Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>