Microbiology Editor’s Choice: how does chronic Staphylococcus aureus infection influence cystic fibrosis?

Posted on February 4, 2021   by Microbiology Society

Each month, a manuscript published in our flagship journal Microbiology is chosen by a member of the Editorial Board. This month, the paper is titledAn ex vivo cystic fibrosis model recapitulates key clinical aspects of chronic Staphylococcus aureus infection’ and was chosen by Professor David Grainger.

Staphylococcus aureus is a major constituent of the cystic fibrosis (CF) lung, but the pathological role of the bacterium is not well defined. In this work, Sweeney and co-authors describe an ex vivo model system for studying S. aureus that offers benefits over currently models. Most notably, their system induces S. aureus behaviours known to be associated with infections studied in the clinic. As such, this work should provide important underpinning for future studies of mechanisms driving CF lung pathology.

An ex vivo cystic fibrosis model recapitulates key clinical aspects of chronic Staphylococcus aureus infection

We have developed a model to study bacterial infection in the lungs of people with cystic fibrosis (CF). We use pieces of pig lung and artificial mucus to replicate the clinical environment more accurately than simple in vitro models. In our model, Staphylococcus aureus demonstrates characteristics similar to those observed in clinical disease, including small colony variants, antibiotic tolerance and preferential aggregation in mucus. This is important because animal models do not always reproduce these features. In mice, in particular, Staphylococcus infection leads to abscess formation, a phenomenon not seen in our model or the human CF lung.

We spoke with the co-author Niamh Harrington to find out more:

What is your institution and how long have you been there? 

I am a PhD student at the University of Warwick and joined in September 2017.

What is your research area?  

My research focuses on chronic biofilm infections in the cystic fibrosis lung, developing the pig lung model to better replicate clinical infection. My work, as part of Dr Freya Harrison’s research group, aims to further understand key aspects of biofilm infection and how it is influenced by the infection environment. We hope this work can enable more effective treatment plans and novel antimicrobials to be developed in the fight against highly drug resistant biofilm infections.

What inspired you to research this topic?  

I have always been interested in bacterial infections and the global threat posed by antimicrobial resistance means that this research is more important than ever. Development of lab models that can more closely mimic the human infection environment are essential in accelerating and improving development of new treatments. Research on lab models that can more accurately predict effectivity of antimicrobial treatments are also important to prevent those who must take them undergoing unnecessary rigorous treatments.  

What is the most rewarding part of your research? 

The troubleshooting aspect of model development, although frustrating at times, is one of the most rewarding parts of my project. It has allowed me to broaden my approach to research and definitely build resilience. Although, the most important part is feeling like we are making a difference in tackling antimicrobial resistance (AMR), and hopefully the model will be able to make a tangible difference to treatment development in the future. It has also been amazing to get to work alongside so many inspiring researchers, both within the group and collaborators!

 What would you be doing if you weren't a scientist? 

I would probably be working for a non-profit organisation that funds scientific research, making research accessible to others by engaging the public in ongoing research projects and helping to facilitate further research – alongside fulfilling my love for a chat!

Follow Niamh and Esther Sweeney on Twitter.