Cartilege Repair Project
Undergraduate's Experiments Mix Two Types of Cells to
Promote Growth of New Tissue
Using adult and embryonic stem cells from mice, a Johns Hopkins undergraduate is conducting important experiments in a project aimed at growing new cartilage to repair injured knees and other body parts.
Thanissara Chansakul, a junior chemical and biomolecular engineering major, is helping a university research team find out whether mixing the two types of stem cells with a particular growth medium will cause the cells to thrive, multiply and turn into the building blocks for cartilage.
Early test results have been encouraging. "This is a key step that moves our lab a little closer to its goal of growing new cartilage through tissue engineering," said Chansakul, who is known on campus by her nickname, Noon.
Chansakul, with Johns Hopkins doctoral student H. Janice Lee, presented preliminary findings last fall during a poster session at the annual meeting of the Biomedical Engineering Society. Continuing to work with Lee and supported by a university grant for undergraduate research, Chansakul is now seeking to replicate the results for a paper that she and Lee will submit to a peer-reviewed scientific journal.
This is not the first time her strong science skills have put the 21-year-old undergraduate from Bangkok, Thailand, in the spotlight. As a high school student in 2001, Chansakul received a golden medal and the highest score in the International Biology Olympiad, held in Brussels, Belgium. In the event, she competed against 150 other students from 38 nations.
That achievement led to a college scholarship from the government of Thailand. "I applied to a lot of schools," Chansakul said. "I came to visit Johns Hopkins, and I really liked the biomedical engineering program and research opportunities here."
After completing her freshman year at Johns Hopkins,
she secured a summer job working alongside other
undergraduates, graduate students and postdoctoral fellows
in the lab of
Jennifer Elisseeff, an assistant professor of
engineering. "I was really interested in tissue
ngineering," Chansakul said, "and I always wondered what we
could do with stem cells. I was interested in their medical
In her Homewood campus lab in Baltimore, Elisseeff is pioneering a method of repairing cartilage, the material found in knees, noses and other body parts, without major surgery. The idea is to place cells in a hydrogel, inject the liquid into the body and then harden it with ultraviolet light. Ideally, the gel will hold the cells in place while they multiply and replace damaged cartilage.
To attain this goal, Elisseeff's team needs to find the right cells and the proper medium to build new cartilage. One strategy is to coax stem cells to turn themselves into chondrocytes, the cells that make up cartilage. But stem cells do not always cooperate with this plan. Embryonic stem cells, derived from early embryos, have the ability to replicate indefinitely and differentiate into many cell types. Yet they do not always survive in the lab's hydrogels, and when they do survive, the researchers need to find right biochemical medium to get them to form cartilage. In contrast, mesenchymal stem cells — adult stem cells that are more inclined to turn into cartilage — are not plentiful enough to complete the injury repair project on their own.
To overcome these drawbacks, Elisseeff's lab, believed to be the only one in the country to do so, is testing a mix of adult and embryonic stem cells in an effort to generate new cartilage. Chansakul is conducting some of these experiments. "We're trying to find the best biological conditions to increase the survival rate of these cells and to get them to turn into the cells that make up cartilage," she said. When she's not in the lab or attending to her own studies, Chansakul serves as a teaching assistant in a general chemistry lab class and participates in Circle K, a campus service organization, and Alpha Epilson Delta, the pre-med honor society. In the latter group, she serves as tutoring chair, leading sessions to help fellow students with physics, chemistry and biology topics. She also finds time to serve as secretary of the JHU Table Tennis Club.
Her Provost's Undergraduate Research Award provided funds for the experimental work she conducted last fall in Elisseeff's lab. Elisseeff cautioned that the mice cells in Chansakul's tests do not always behave exactly the way human cells do. Nevertheless, Elisseeff said, the experiments do yield useful information about the way embryonic and adult stem cells influence one another and how well they survive in the hydrogels.
The undergraduate research grants are helpful, Elisseeff said, because they allow students like Chansakul to gain important hands-on lab experience. "They're invaluable," the faculty member said. "My students who have gotten these awards are usually the real academic superstars."
On March 16, Steven Knapp, university provost and senior vice president for academic affairs, will host the 13th annual Provost's Undergraduate Research Awards ceremony, which honors the 42 winners who conducted their projects in the summer and fall of 2005. Since 1993, about 40 students each year have received PURA grants of up to $3,000 to conduct original research; results of some projects have been published in professional journals. The awards, funded through a donation from the Hodson Trust, are an important part of the university's commitment to research opportunities for undergraduates.
The Johns Hopkins University is recognized as the country's first graduate research university, and has been in recent years the leader among the nation's research universities in winning federal research and development grants. The opportunity to be involved in important research is one of the distinguishing characteristics of an undergraduate education at Johns Hopkins.
The Provost's Undergraduate Research Awards program provides one of these research opportunities, open to students in each of the university's four schools with full-time undergraduates: the Krieger School of Arts and Sciences, the Whiting School of Engineering, the Peabody Conservatory and the School of Nursing.
Color images of Chansakul and Elisseeff available; contact Phil Sneiderman.
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