During Spring Festival in early 2020, the sudden emergence of a new virus caught the world by surprise.

Dr. Tiannan Guo's Laboratory at Westlake University, where Yaoting Sun is located, is one of the most advanced proteomic big data laboratories. During the initial period of the outbreak, the lab quickly formed a 22-person research team to tackle work related to the molecular pathology of patients with COVID-19. This was done by measuring and analyzing the differences in proteome and metabolome in sera samples from 46 patients with mild to severe symtoms and 53 control individuals, combined with machine learning. This way they were able to propose a potential early prediction method. Yaoting was the main force behind the data mining team due to her rich experience in the intersection of proteomics and artificial intelligence.

The proteomic data and metabolomic data of mass spectrometry had all been collected and analyzed. The team identified 93 differentially expressed proteins and 204 metabolites with altered characteristics in the sera samples of severely ill patients. Next, they needed to accurately dig out the iconic molecules from these data, then use them to develop artificial intelligence programs.

Her laboratory was working almost 24 hours a day. Her mentor Tiannan Guo continued to encourage by saying that in the future they would look back at that time and miss it because they were making contributions for all humanity.

"At that time, I only slept four or five hours a day at most," Yaoting Sun recalls. Yaoting is a rock music enthusiast, in order to fight against sleepy bugs, she wore noise-cancelling headphones and turned the volume of the music to the maximum, "the heavy metal music would stimulate me, so I could focus on the work at hand."

After countless attempts, Yaoting tried to eliminate the overlap between the differential molecules caused by the severe symptoms and the differential molecules caused by the flu. The data finally changed from an ugly duckling to a white swan. She was excited to discover that the remaining proteins were mainly concentrated in the three pathways of human physiological functions: platelet degranulation, macrophages and the complement system. She also tried to eliminate more than a dozen different data analysis methods for severe patients with underlying diseases, gender factors, etc., and found that the remaining proteins still pointed to the same pathway: platelet degranulation, changes in macrophage function, and the complement system activation. "Dr. Guo, we must pay attention to these three!" She shouted excitedly in Dr. Guo's office.

In the end, Tiannan Guo's team succeeded in screening out 22 proteins and 7 metabolites for severe patients with COVID-19, which might be used in selection of potential blood biomarkers for severity evaluation.

On July 9, 2020, Cell published online the research paper of Tiannan Guo's team entitled, "Proteomic and Metabolomic Characterization of COVID-19 Patient Sera". Yaoting participated as the co-first author. Since then she has participated in the publication of four COVID-19-related studies in total, two of which were published in Cell.

Thinking about that time, Yaoting observes, "COVID-19 was ruthless to all humanity. It has been the greatest honor of my life to have the opportunity to contribute to the fight against the pandemic at Westlake University!"