Professor Isabel Roditi from the University of Bern is a renowned expert on trypanosomes, the pathogens that cause African sleeping sickness. She is currently hoping to prove that these parasites do not spread randomly in their host organisms, but navigate from organ to organ in a targeted manner. If this is true, it would be the very first known example of targeted parasite migration. This could provide clues for improved control of the pathogen.

The European Research Council (ERC) has awarded the professor an ERC Advanced Grant of 2.5 million euros to finance her project. This grant is one of the most prestigious European research awards; it is only awarded to established top researchers.

Isabel Roditi plans to start her five-year ERC project Tryptaxis (A sense of direction: cooperative behaviour and chemotaxis in the life cycle of Trypanosoma brucei) at the Biocentre of Julius-Maximilians-Universität Würzburg (JMU) in Bavaria, Germany, on 1 November 2024. There, she will use her expertise to strengthen the department chaired by Professor Markus Engstler, who has also been conducting research on the sleeping sickness pathogen for many years.

Background to the ERC Project Tryptaxis

All living creatures use their senses to orientate themselves in their environment. This enables them to find "safe havens" to improve their chances of survival or avoid danger. Humans rely on their sight, smell, taste and other senses. In contrast, individual cells such as bacteria often follow differences in the concentration of chemical compounds; they orientate themselves according to these so-called chemical gradients.
Trypanosomes, which cause sleeping sickness in humans and a similar disease in animals, also consist of just one cell. The parasites switch between two hosts, mammals and tsetse flies. To complete their life cycle, they must migrate through different tissues of their hosts.

"Surprisingly, practically nothing is known about how trypanosomes and other parasites perceive their environment," says Isabel Roditi. Researchers currently assume that the pathogens act as individuals and that interactions with the tissues of their host organisms are largely determined by contacts between surface molecules.

"However, parasites are more autonomous and manipulative than we think," says the professor. Recent work by her research group has shown that trypanosomes not only perceive chemical gradients, but can also manipulate them to their advantage. "My theory is that this phenomenon, known as self-steering, enables trypanosomes to migrate in groups, settle in the target tissues of their hosts and increase their chances of survival and transmission between hosts."

The Professor's Career

Isabel Roditi, born in 1956, studied biochemistry at the University of Oxford (UK) and obtained her doctorate in virology at the University of Cambridge (UK) in 1983. There she switched to the field of parasitology as a postdoc, followed by five years of research at the University of Karlsruhe from 1985.

In 1990, Isabel Roditi became head of a research group at the Institute of General Microbiology at the University of Bern. In 1999 she was appointed Professor and Co-Director of the Institute of Cell Biology. She has been retired since 2022. From November 2024, she will continue her research at the Chair of Zoology I (Cell and Developmental Biology) at the Biocentre of Julius-Maximilians-Universität Würzburg.

She has received several prestigious awards for her work. Among other things, she was honoured twice as an International Research Scholar of the Howard Hughes Medical Institute (USA), each time with an award of 500,000 US dollars. The Bill and Melinda Gates Foundation (USA) honoured her together with her Swiss colleague Professor Reto Brun with a Grand Challenges Explorations Award, endowed with one million US dollars.

Facts About African Sleeping Sickness

The life-threatening African sleeping sickness is caused by single-celled pathogens called trypanosomes. The flagellates are transmitted to humans through the bite of the tsetse fly. Those affected initially develop headaches and aching joints, followed by confusion, emaciation and other symptoms. Eventually they fall into a coma and die.

There are no vaccines against the pathogens; some of the available drugs have extreme side effects. Better remedies against the disease are therefore urgently needed. Because trypanosomes also infect cattle, goats and other livestock, they cause additional damage. In some areas of Africa, animal husbandry is impossible because of trypanosomes.