Sandra Breum Andersen

Sandra Breum Andersen

A partnership between humans and bacteria

The word ‘bacteria’ doesn’t exactly hold positive connotations, since we usually associate them with disease, dirt, food poisoning and other plagues. However, if you ask Sandra Breum Andersen – PhD in evolutionary biology and one of the new 2020 Lundbeck Foundation Fellows – what she thinks about bacteria, you will receive quite a different answer. Her relationship with bacteria is based on profound scientific knowledge, and she regards bacteria as a group of organisms closely related to human beings:

‘Humans and other mammals have an age-old partnership with bacteria – a partnership that is still ongoing today. Bacteria and animals interact, and it is these interactions that I’ll be studying more closely. One of the questions I’ll be exploring is how these interactions have shaped both humans and bacteria,’ says Sandra Breum Andersen. She will use her fellowship to establish her own research group at the University of Copenhagen’s Department of Biology.

How bacteria and humans interact – and in certain cases battle one another – is a research field that has steadily risen into the spotlight over the past 10 to 15 years. One of the aims is to gain a better understanding of the many hundreds of kinds of bacteria that live in the human digestive system, performing a variety of tasks. Some of the theories being investigated by research groups around the world concern the role of gut bacteria in obesity and diabetes.

Sandra Breum Andersen will conduct tests with the Helicobacter pylori bacterium in order to gain more knowledge about how humans and bacteria have evolved through this ancient partnership. She explains:

‘We usually just call it H. pylori, but it’s best known as the stomach ulcer bacterium because it can cause stomach ulcers. It can actually also play a negative role in the development of stomach cancer. The reason why I want to study this particular bacterium is because it also has positive characteristics. Recent studies show that H. pylori can provide protection against cancer of the oesophagus and development of asthma and allergies. Based on the knowledge we have about how H. pylori affects the immune system and gut bacteria, I will also test whether it could provide some protection against malaria and obesity.’

Some of the tests Sandra Breum Andersen will be performing involve mice which have been given a special high-calorie diet. Other tests will be performed in cell cultures. She explains:

‘My main goal is to gain new knowledge about the evolutionary journey humans and bacteria have taken together through the ages – and to understand what it means for our health and disease. And new knowledge about human-microbe interactions could also impact on, for example, drug design.’