Three speakers, three fascinating science stories and a well-filled lecture hall. The Niko Tinbergen Lecture had a successful restart on 10 December 2019.
Stem cells against fertility problems
After a warm welcome by interim dean Hubertus Irth, two young Leiden professors briefly spoke about their research. LUMC Professor of Developmental Biology Susana Chuva de Sousa Lopes wants to help women with fertility problems. Scientists and doctors would like to know much more about the causes of these problems, but they still lack for example an in vitro model to study the development of egg cells, Lopes explains.
She and her group are working on various techniques to better understand egg ripening and to allow this process to take place outside the body. For example, it is already possible to make miniature ovaries based on stem cells in the lab. Very special is the research into the possibilities of adapting X and Y chromosomes in stem cells. Female stem cells can only grow into egg cells, while male stem cells can only produce sperm cells. Lopes: ‘If stem cells can grow into both types of germ cells, same-sex couples would be able to have children that are genetically their own.’ Lopes does not know whether society is yet ready for this. She does cite the example of Louise Brown, the first IVF baby 41 years ago. ‘It was controversial then, but now we think it’s perfectly normal.’
Then professor of Ultrastructure Biology Ariane Briegel of the Institute of Biology explains how she, like Niko Tinbergen, studies congenital behaviour, but then of animals that you can’t spot with the naked eye. With super-powerful microscopes, she looks at the locomotion of bacteria, which, for example, look for food.
They have a locomotor system that is controlled by a kind of bacterial nose,’ explains Briegel. This is clearly visible in her microscope photos. Some bacteria even have more than one type of nose, she points out. Briegel: ‘That’s not just a nice story for you to tell at the Christmas table, but actually really useful to know about it.’ Diseases like cholera are caused by bacteria, which use their nose to find and invade hosts. Briegel collects knowledge about these mechanisms, which other scientists can hopefully use to better fight these diseases.
Stem cells in the gut
After the break, keynote speaker Hans Clevers talks about the type of cell with which he acquired worldwide fame: stem cells, i.e. cells that are capable of producing other types of cells. With his research, Clevers did pioneering work on specific gut cells, which had been known for some time, but whose function was still unclear. Stem cells, Clevers believed, but colleagues were initially sceptical. Step by step, however, he showed that these cells were long-lived and capable of producing other cell types: they were stem cells indeed.
On the basis of that discovery, Clevers’ group later succeeded in growing mini-guts in the lab. In mice, these are capable of repairing existing intestinal damage quickly: a hopeful prospect for people with Crohn’s disease, for example.
In the meantime, developments in the production of stem cells and mini-organs are moving fast, according to Clevers. And that’s good news for people with all kinds of hard-to-fight diseases. Doctors can grow pieces of the patient’s tissue outside the body in order to test the effectiveness of medicines and treatments. This way, they can see in advance whether the medicines will be effective or not. According to Clevers, studies in which grown tissues are exposed to cancer medication already give a good prediction for 80 to 85 per cent of the cases. ‘This means that personalised medicine is becoming more and more a reality.’
About the Niko Tinbergen lecture
In the Niko Tinbergen lecture, an expert in (medical) biology shows how science may contribute to societal challenges; what scientific innovation can entail and what this can mean for our future. The lecture takes place once every two years and follows on from an earlier series, which ran from 2003 to 2013. Big names in biology such as Richard Dawkins, Jared Diamond and E.O. Wilson visited Leiden at the time.