
With a Ph.D. in Translational Biomedical Sciences under his belt, Junsik Sung is closer to achieving his dream of becoming an independent researcher who develops new drugs to treat human diseases.
By LaTina Emerson
Junsik Sung has wanted to become a scientist since he was 5 years old. His lifelong dream is coming true this fall as he graduates with a Ph.D. in Translational Biomedical Sciences from the Institute for Biomedical Sciences.
“Biology was the only thing that I wanted to do since I was a kid,” Sung said. “I didn’t really think about other paths.”
Originally from Seoul, South Korea, Sung earned a bachelor’s degree in biology from the University of Utah and a master’s degree in pharmaceutical science from Seoul National University.
After completing his master’s program, Sung knew he still had a lot to learn and wanted to earn a Ph.D. Unsure of what school to attend, he searched for research labs in the United States and came across work by Didier Merlin, a Regents’ Professor in the Institute for Biomedical Sciences who studies gastrointestinal diseases.
Sung found this research area interesting, so he contacted Merlin about joining his lab and applied to the Translational Biomedical Sciences Ph.D. program. He was accepted and joined the lab as a graduate student.
He and fellow researchers developed a novel oral drug delivery system to treat inflammatory bowel disease (IBD), a chronic and relapsing gastrointestinal disorder that affects more than 3 million people in the U.S. and 5 million people worldwide. Patients with ulcerative colitis and Crohn’s disease, two types of IBD, need better therapeutic options because current treatments have adverse side effects.
To treat ulcerative colitis in mice, the researchers encapsulated a gene called IL-22 mRNA in lipid nanoparticles and delivered it orally to target the inflamed colon.
“IL-22 is a therapeutic agent that is documented to have a potent anti-inflammatory effect against ulcerative colitis,” Sung said. “Treating colitic mice with the IL-22 mRNA encapsulated within lipid nanoparticles accelerated the healing process in the damaged mucosal tissues, meaning that mice with colitis almost recovered close to normal levels.”
The findings were published in the journal Biomaterials.
“We started this project during the COVID-19 pandemic” Sung said. “The COVID-19 vaccine from Pfizer uses lipid nanoparticles to successfully deliver mRNAs to prevent spread of COVID-19. While the COVID-19 vaccine is an intramuscular injection, our method is the oral delivery system, so that’s what is different. It is a unique and safe gene delivery system to treat ulcerative colitis.”
During his Ph.D. studies, Sung published 16 papers, including a first-author paper in the American Journal of Physiology–Gastrointestinal and Liver Physiology.
After graduation, Sung will work as a postdoctoral research fellow in pharmaceutical science at the University of Maryland, where he will continue similar work with nanoparticles, but with different target diseases. While he’s not the first in his family to earn a Ph.D., he’s the first to pursue a biomedical science career.
Sung also chose the Translational Biomedical Sciences program because he’s interested in how science can be applied to improve existing drugs or design new drugs to treat human diseases.
“My ultimate career goal is to become an independent researcher who can continue to work in translational biomedical research to develop new drugs for human disease treatment,” Sung said. “I’m always interested in the therapeutics research of human diseases. Basic science is important, but I like that biomedical research is applicable to clinical use. That’s more attractive to me and motivates me the most.”
He enjoyed the variety of classes offered by the program, which allowed him to meet many professionals in the biomedical field, learn about other career options and develop a wider perspective.
“This program is also great because we have excellent mentors and professors who teach students how they can grow into independent researchers,” Sung said. “That’s something that I liked the most about the Ph.D. program.
“I really loved working with Dr. Merlin. He’s an amazing adviser and mentor. I can say that he’s one of the best mentors that I have ever met during my science career. He’s generous and patient with students like me, and he gives enough time and opportunities to learn new things. He tries his best to guide students in the most efficient way. He’s always full of new ideas. I really learned a lot about what is important in the lab and life as well.”
At Georgia State, Sung also earned a graduate certificate in public health, which he thinks will be beneficial during his career.
“I wanted to see different views on life science,” Sung said. “I wanted to understand the public health view of human diseases, such as how they deal with diseases and how they analyze them.”
Photo by Michael Daniel