COSAM students translate global challenges into three-minute stories

Whether measuring cellular stress in human brain immune cells or tracking hatchling tortoises in coastal plain sandhills, two graduate students in the College of Sciences and Mathematics are tackling questions with global significance as finalists in this year’s Three Minute Thesis competition. One studies the impact of tiny plastic particles found in air, water and everyday life on human health. The other focuses on a keystone species whose decline ripples across whole ecosystems.

Though their fields diverge, they share a commitment to clear, accessible science.

Making the microscopic visible

Second-year biological sciences graduate student Seth Vogt, who took home the competition’s runner-up prize, grew up just north of Atlanta and first came to Auburn as an undergraduate. He returned for graduate school after discovering research in Priscila Lotsch’s lab that blended his interests in biomedical science and materials engineering.

His work explores how micro and nanoplastics (MNPs) affect human brain immune cells. Microplastics are smaller than five millimeters, while nanoplastics are small enough to require specialized equipment to detect. MNPs have been detected in nearly every tissue in the human body — from the bloodstream all the way to the brain. However, researchers still don’t understand what happens to our health when these particles are present.

To model realistic exposure, Vogt uses microplastics provided by Prof. Tham Hoang in Auburn’s School of Fisheries, Aquaculture and Aquatic Sciences. He breaks down items like cups and utensils into tiny fragments and exposes human brain immune cells to relevant concentrations of MNPs to measure stress, metabolic changes and inflammation. Most of the MNPs we encounter come from what we eat and drink, as well as the tools we use to eat and drink these products, making these utensils a powerful proxy for what may already be inside the human body.

His findings offer little optimism. Cells exposed to the smallest particles show major signs of stress and a noticeable loss of mitochondrial function, reducing their capacity to produce energy and control cellular homeostasis. The nanoplastic fragments trigger the strongest effects. That pattern mirrors the scale of the problem he hopes people understand.

“Micro- and nanoplastics are everywhere,” he said. “They’ve detected them at the bottom of the Mariana Trench and in space at the upper layers of the atmosphere.”

No organism tested so far has been free of them. And for people looking to reduce exposure, Vogt’s advice is straightforward.

“Get rid of all the plastic in your kitchen,” he said, noting that black plastic utensils leach some of the highest amounts of particles when heated. “Microplastics are in literally every single consumer item, more than people realize. It comes as quite a shock to learn just how widespread this issue has become.”

Protecting an ecosystem engineer

Fourth year biological sciences PhD student Anet Filipova came to Auburn through an unexpected path. She grew up in Bulgaria, completed her undergraduate degree in Scotland and originally planned to pursue a doctorate somewhere in Europe. But she found herself drawn to the Southeast for one compelling reason.

“I was always fascinated with reptiles,” she said. “How mystical, secretive and underestimated they are.”

That fascination led her to Tonia Schwartz’s lab and the gopher tortoise. These tortoises are considered ecosystem engineers because the deep burrows they dig shelter more than 400 other species. As their populations decline across the Southeast, preserving them has become increasingly urgent.

Hatchlings face particularly high risks. One of the most serious threats comes from fire ants. To counter early mortality, conservation groups use a strategy called head starting, where eggs or hatchlings are raised in controlled conditions for their first year before being released. But these programs typically bypass a critical part of tortoise biology: cold dormancy. During winter in the wild, young tortoises slow their metabolism, stop eating and rely on stored resources to survive.

“You’re skipping a very, very important part of their biology,” Filipova said.

Her dissertation examines what happens when that winter slowdown is skipped. She raised 60 hatchlings for nearly a year, giving half a natural dormancy period and keeping the rest in constant warm conditions. The dormant group ended the experiment smaller, but their daily growth soon matched the others, and their metabolism shifted in predictable ways, including depleted glucose and reliance on stored fats.

Her next step is to look beyond outward traits.

“Maybe certain genes are having a very crucial role in helping those animals survive through those cold months,” she said, adding she is now analyzing gene expression to see how dormancy shapes their internal response to environmental stress.

Much of her attachment to the species comes from the long months she spent finding nests and raising hatchlings. Searching for eggs in the heat of Alabama summers was grueling, but her time with the young tortoises made the work feel worthwhile.

“I absolutely knew every single one of them,” Filipova said.

The hatchlings had personalities, too. One ran laps every morning. Another often flipped upside down. One grew so quickly it was nicknamed “the mutant.” But for Filipova, the most meaningful moments come later, when collaborators return to the field and find her hatchlings alive.

“It means your efforts have been rewarded,” she said.

She hopes continued grant support will keep the project moving forward for the good of the species.