Dr. Yusha “Katie” Liu joined ISCRM in 2023 as an Assistant Professor in the Division of Plastic Surgery, Department of Surgery
Yusha “Katie” Liu figures that her love of medicine and biology goes back to high school – and maybe further, if you count the toy doctor’s kit her parents gave her when she was three years old. As an undergraduate student at Duke University, Liu double majored in biology and psychology. She started doing research in a molecular biology lab during her first year. Whether or not she knew it at the time, the combination of interests would serve the future surgeon well.
Rather than choose between research and medicine, Liu moved west to attend the combined MD/PhD degree Medical Scientist Training Program at the University of Washington, where she studied serotonin signaling in fear and anxiety behaviors in the lab of John Neumaier in the Department of Psychiatry and Behavioral Sciences. However, it was a rotation in her third year of medical school that ultimately called to Liu.
“When I did my surgery rotation, I felt like I was really in the zone in the operating room,” says Liu. “It was exciting to be doing something so tangible and immediately impactful for the patient. At the same time, I knew that I wanted to pursue research as well. I want to help my patients as a surgeon but also want to advance the field and discover new treatments.”
Helping Patients in the Lab and the Clinic
For Liu, that makes the University of Washington an ideal place to build her career as a surgeon scientist. In 2023, Liu became an assistant professor in the Division of Plastic Surgery, Department of Surgery, and a faculty member in the Institute for Stem Cell and Regenerative Medicine (ISCRM). Liu will divide her time between Harborview Medical Center and her lab on the UW Medicine South Lake Union campus.
As a clinician, Liu is particularly drawn to peripheral nerve surgery, a subspecialty of plastic surgery, and a perfect way to weave together her neurobiology background and her clinical and research interests. Liu explains she is motivated by experiences she had during her training with patients with injuries to the brachial plexus, a network of nerves in the neck that connects the spinal cord to the shoulder, arm, and hand.
“The patients I saw with brachial plexus injuries were usually young people who had been in car or motorcycle accidents and had paralysis in their entire arms. From a clinical point of view, we know that surgery within a certain timeframe leads to the best hope for restoring function. At the same time, the outcomes are suboptimal even in the best-case scenario, and there is still so much to be discovered about peripheral nerve injuries.”
One of the biggest challenges is how slowly nerves regenerate. Scientists estimate that nerve fibers known as axons grow at a millimeter per day or an inch a month. That pace could mean multiple years for a nerve of the brachial plexus in the neck to grow to the wrist and hand. Meanwhile, as time passes, muscles impacted by a peripheral nerve injury gradually lose their ability to reestablish connection with the nerves. Keeping the window open longer could therefore help doctors maximize recovery for patients.
There is a small silver lining, says Liu. “You do get to develop a longstanding relationship with the patient. From the time of their injury, it can take years for surgery, recovery, and rehabilitation. That means we get to be a surgeon and also a cheerleader through the entire care journey, which is really meaningful to me.”
Liu also spearheaded the creation of a new multidisciplinary peripheral nerve clinic at Harborview to streamline care for these patients, with a collaborative team of surgeons, rehabilitation physicians, rehabilitation psychologists, radiologists, hand therapists, and interventional pain specialists.
For Liu, inspiration moves two ways between the lab and the clinic. “When I approach research, it really begins with recognizing where I could potentially intervene during surgery or clinical care, and then figuring out what I need to study to develop more effective therapeutic treatments.”
Joining a Collaborative Research Community
With that mindset, the Liu Lab will have two main interests. First, the lab will study how nerves regenerate – and whether it is possible to accelerate that process in ways that lead to better outcomes for patients. Second, Liu and her team will explore how to prevent degeneration of motor endplates in the muscle, so that when axons do eventually reach the target muscle, new neuromuscular junctions can form to restore the connection between nerve and muscle.
Liu is immensely grateful to the Department of Surgery and ISCRM for the opportunity to pursue basic and translational science research alongside her clinical work. She adds that she is fortunate to be part of the Neuromuscular Disease Research Group, a collaboration of ISCRM faculty members David Mack, PhD, Mark Bothwell, PhD, and Alec Smith, PhD.