“I'm more attracted to solving interdisciplinary problems”
Sangwoo Kim © Titouan Veuillet/Adrian Alberola Campailla CC BY-SA
Sangwoo Kim, head of the new Mechanics of Soft and Biological Matter Laboratory in EPFL’s School of Engineering, finds inspiration in applying mechanics and physics principles to biological questions.
As an undergraduate at the Pohang University of Science and Technology in South Korea, Sangwoo Kim excelled in mechanical engineering and mathematics. With an early interest in fluid mechanics, he never expected his career to require biological knowledge – of embryonic zebrafish development, for example. But in the newly launched MESOBIO laboratory in the Institute of Mechanical Engineering, his team aims to gain fundamental understanding of biological systems like embryonic tissues and cellular matters based on theoretical tools from mathematics, physics, and engineering.
“We want to develop novel theoretical frameworks to understand emergent structures, dynamics, and mechanical properties within living systems and soft and active materials,” Kim explains in his office on the EPFL campus. Since his appointment as a Tenure Track Assistant Professor, his research has mainly focused on theory, but he is working hard to get the experimental side of things up and running.
“Collaboration across multiple domains is essential to tackling the interdisciplinary problems that we’re focusing on. Within EPFL’s open and collegial scientific environment, we’ll collaborate with several labs in the School of Life Sciences – notably the Microbial Mechanics Lab and the Segmentation Timing and Dynamics Lab. I’m also setting up a cell culture lab for my group. While our primary research focus is theoretical, we’ll encourage and incorporate experimental aspects to create synergies with our theoretical work.”
Toward a unified model of biological tissue development
Kim says that it was during his PhD in Theoretical and Applied Mechanics at the University of Illinois at Urbana-Champaign that he first began to investigate biological systems. Specifically, he studied the relationships between statistics, geometry, and mechanical states that are universally observed in inert soft materials, as well as in living biological and cellular materials. Then, as a postdoctoral fellow at the University of California, Santa Barbara, Kim further developed an interdisciplinary interest in embryonic tissues thanks to his advisor; a physicist by training who was studying biological systems, including zebrafish embryos.
Kim’s zebrafish research focused on embryonic tissues that can actively tune cellular properties to attain more fluid-like or solid-like states; a process that is reminiscent of phase transition behaviors. He explains that such phase transitions in biological tissues indicate that embryonic development is a complex process regulated not just by genetics and biochemistry, but also by physics and mechanics principles.
“To develop a simple but generic model to understand these systems, we look at interactions at the cellular scale to predict emergent properties at the tissue scale. Our approach, which facilitates a holistic understanding of these processes, can potentially be applied to treating developmental defects.”
He adds that while numerous theoretical models exist for studying specific biological tissues, he hopes his research will contribute to the development of a more comprehensive and unified model that can be used to study a wide range of such tissues.
Learning on the fly
Kim will be co-teaching Pedro Reis’ bachelor course on structural mechanics, as well as developing his own new master’s course on the mechanics of soft and biological matter. In addition to teaching, he sees a lot of learning on his own part, both when it comes to charting a relatively new interdisciplinary path and adjusting to life in Switzerland.
“I had career opportunities in the US, but the supportive research environment and opportunities for collaborations attracted me to joining EPFL. It has been a big change – the academic system is different and I don’t speak French – but it has been going well, and I am looking forward to having more time to explore Swiss hiking trails!”
Persistence and exploration are of course central to any scientific career, but they are especially key for Kim in his work at the intersection of mechanics, physics, and biology – the latter of which he admits was one of his weakest subjects as an undergraduate.
“It takes time to learn languages from different disciplines: biologists talk about genes, proteins, and signaling pathways that I don’t fully understand, while they may not fully understand when I talk about phase transitions. But the key is having a conversation and asking questions, which can always lead to even more interesting questions. That’s the process of science.”
When asked if he ever finds the multidisciplinary nature of his work to be a disadvantage, Kim shakes his head.
“I’m actually more attracted to solving these kinds of interdisciplinary problems. I plan on having a very interdisciplinary lab, with students from many different backgrounds,” he says, adding: “I find it fascinating and inspiring that we have so many open questions in biology, and applying physics and mechanics principles can significantly advance our knowledge. These are very complex systems, and to understand them, we need input from both sides.”