“Dealing with challenges makes you grow as a scientist”

17 April 2018 – It took quite some time and energy before TiFN PhD fellow Marcela Fernández had her advanced high-throughput microscopy scratch assay up and running. But she succeeded. She used it to study the influence of oral bacteria and saliva on wound healing, and to predict what happens when an individual does not brush his teeth for two weeks. On March 16 this year, Fernández successfully defended her thesis at Wageningen University.

Imagine going on a two-week hiking trip in the mountains and forgetting to bring your toothbrush. What would happen to your oral health? Would you be in greater danger of developing gingivitis? With just a few drops of your saliva Fernández can predict how the ‘ecosystem’ in your mouth will develop. “If there is an increased proportion of Selenomonas sputigena in your saliva, you are likely to suffer a stronger inflammatory response. If Veillonella dispar is predominant, you might be among the lucky few with improved oral health”, says the Costa Rican scientist, who obtained her MSc in Medical Biotechnology at Wageningen University in 2012.

Exploring saliva
Fernández did not need to go on a hiking trip to find the answers. Instead, together with a number of other PhD fellows, she conducted a two-week clinical study at the ACTA (Academic Centre for Dentistry Amsterdam) research labs – one of the scientific partners in the TiFN Oral Health project. Sixty-one volunteers agreed to abstain from all oral hygiene activities during the trial period, and had their saliva tested regularly.  

Fernández developed and optimised an automated high-throughput scratch assay  connected to a mathematical model. “The aim was to measure metabolite levels in saliva over time, and link them to re-epithelialization – an essential component of wound healing – in the gums”, she explains. Setting up the testing procedure was not easy, she stresses: “I was the only one in our project team working with high-throughput microscopy, so I had to learn all about it and start up the procedure by myself.”

Fernández succeeded in identifying the metabolite signatures of 10 metabolites, which she validated via re-epithelialization experiments in the lab. “Using these signatures, we correctly predicted the re-epithelialization capacity of the remaining 242 saliva samples in the study”, she says. “We also discovered that increased re-epithelialization capacity was related to increased mucosal damage.”

Diagnostic tools
TiFN’s industry partners welcomed the insights and the new testing protocol with enthusiasm. “They believe the outcomes contain potential for the development of new diagnostic tools”, says Fernández, who is excited that her work is valued by the industry. She looks back very positively on her time as a TiFN PhD fellow. “I enjoyed working in a team, and the challenges I had to face made me a better scientist”, she stresses.

Team work
Fernández is now working as a post-doc scientist at the Host-Interactomics Department of Wageningen University, investigating cell lines and organoids. “I am in collaborations with research partners in many different countries, and team work, just as at TiFN, is crucial for success.”

Want to know more about Fernández’s work? Click here.