York researchers step up hunt for new therapies for tropical killer
Posted on 15 July 2005
Scientists in the University's Immunology and Infection Unit are part of a huge international collaboration which has sequenced the genomes of the single-celled parasites which cause the human disease, Leishmaniasis.
The results of research published today (Friday 15 July) in Science will help scientists to discover viable treatments for these infections. The paper is the first of a series to be published on the genomes of three related parasitic organisms (christened the Tri-Tryp genomes) that cause devastating diseases in tropical regions around the world. It is part of a major international scientific offensive aimed at tackling these deadly diseases that include African Sleeping Sickness and Chagas' Disease (widespread in Central and South America) as well as the leishmanises.
The York team is headed by Professor Deborah Smith, who is a founder member of the Leishmania Genome Network, set up 10 years ago by the World Health Organisation to initiate a project sequencing the DNA of Leishmania parasites. She is one of more than 100 collaborators from laboratories around the world who are involved in the published research, including the major DNA sequencing centres in the UK and the USA.
This information will set the scene for identifying novel drug targets and vaccine candidates to prevent these devastating human diseases
Professor Deborah Smith
"It has been 10 years of escalating scientific progress and increasing technical know-how to get to this point. It is a big moment for those of us involved. This information will set the scene for identifying novel drug targets and vaccine candidates to prevent these devastating human diseases," she said.
"We are now collaborating with scientists from the Wellcome Trust Sanger Institute who are sequencing the genomes of three more species of the Leishmania parasite including those that cause the most lethal visceral forms of Leishmaniasis. Comparisons between their genomes will allow us to home in on the most important genes that play a role in disease."
Spread by sand flies, the 'visceral' form of the disease, which affects the liver and spleen, is often fatal, and more than 100,000 people, mainly children, die each year, in Africa and the Indian subcontinent. This form of disease is also found in Southern Europe and countries bordering the Mediterranean, affecting people and domestic dogs.
Some other species of Leishmania parasites cause long-lasting skin ulcers, and hundreds of US troops serving in Iraq have already succumbed to the 'Baghdad Boil', as it is known.
Notes to editors:
- There are approximately 2 million cases of leishmaniasis per year in 88 countries worldwide, of which 500,000 are of the potentially fatal form of the disease (visceral leishmaniasis). Although mainly found in developing countries, Leishmania parasites are also found in most countries bordering the Mediterranean, and visceral leishmaniasis is now often associated with HIV infection.
- The genomes of different species of Leishmania are being sequenced by the Wellcome Trust Sanger Institute at Hinxton, together with international collaborators, to provide an important resource for research on the diseases caused by these parasites.
- African trypanosomiasis, also known as sleeping sickness, is caused by species of Trypanosoma brucei and is fatal if left untreated. Symptoms include headache, anaemia, joint pains and swollen tissues, while later in infection, neurological and endocrine disorders occur. As the parasites invade the central nervous system, mental deterioration begins, leading to coma and death. Sleeping sickness claims >50,000 deaths per year with up to 0.5 million cases annually.African trypanosomiasis is closely related to a widespread infection of cattle known as N'gana, which restricts cattle rearing in many prime areas of Africa.
- 120 million people are at risk from Chagas' disease (caused by the parasite Trypanosoma cruzi) with 0.3 million new cases per year. Parasite infection results in fever and swollen lymph glands in the initial acute phase, symptoms that may lead to may severe illness and death, especially in young children. More commonly, patients enter a symptomless phase (of several months or years) when the parasites invade most organs of the body, often causing heart, intestinal and oesophageal damage and progressive weakness. In 32% of those infected, fatal damage to the heart and digestive tract occurs during this chronic phase.
- The University of York's £1.8 million Immunology and Infection Unit was established as a joint initiative by the University's Biology Department and the Hull York Medical School (HYMS) and held its Inaugural Scientific Meeting this week. Apart from Professor Smith's team, there is a second group in the Unit working on leishmaniasis headed by Professor Paul Kaye.
- The Department of Biology at York is one of the country's leading centres for research and teaching across the entire spectrum of the biological sciences. Its international research programmes attract £8 million per year of external funding, employ nearly 300 scientists and were rated 5 in the 2001 Research Assessment Exercise. In 2002, it moved into new £25 million laboratories funded by the Biotechnology and Biological Sciences Research Council under the Joint Infrastructure Fund programme, with additional support from Yorkshire Cancer Research.
- HYMS is a joint venture between the Universities of York and Hull and the NHS. It admitted its first medical students in 2003 and is consolidating its research base with strong collaborative links in and between the two universities and clinicians in the region.
- The Immunology and Infection Unit is the latest boost to Science City York. York was recognised as one of Britain's 'Science Cities' in Chancellor Gordon Brown's pre-budget statement on 2 December 2004. This confirmed the Government's continued investment in science and technology to drive forward the UK's position in the global economy.