UNL engineer aims to reduce blood vessel stent complications

            Each year, more than a million Americans receive stents to prop open clogged heart arteries and other blood vessels, but many are at high risk for suffering reblockages. A University of Nebraska-Lincoln engineer's research may help save millions of people from this debilitating and sometimes fatal complication.

            Linxia Gu, assistant professor of mechanical and materials engineering and a member of UNL's Nebraska Center for Materials and Nanoscience, recently earned a five-year, $406,248 Faculty Early Career Development Program Award from the National Science Foundation to continue her research. These prestigious awards, also known as CAREER awards, support pre-tenure faculty who exemplify the role of teacher-scholars through outstanding research, excellent education and the integration of education and research.

            Stents or stent-based techniques are popular treatments for coronary heart disease and other arterial narrowing, as well as for aneurysm repair. These tiny mesh tubes are inserted using a minimally invasive procedure to keep arteries open.

            Sometimes, however, vascular cells within the arterial wall react to the stent by making new cells that excessively build up and eventually restrict blood flow, which may lead to strokes or heart attacks. This condition, called in-stent restenosis, sometimes occurs months later and without warning symptoms.

            "People in the research community are trying to understand the fundamental mechanism of restenosis," Gu said. "I try to look at it from the cell-tissue-stent interface to see what causes this kind of arterial response."

            She aims to understand the changes cells undergo when stents are introduced and how those changes relate to alterations in arterial tissue structures. Using powerful computers at the university's Holland Computing Center, she will build computer models to essentially peer inside the arterial wall. Initial experiments using a scanning probe microscope operated by the Nebraska Center for Materials and Nanoscience have identified some of the parameters she needs to model cellular and tissue mechanics.

            Gu said the challenge is to couple the mechanical behavior of cells with the mechanics occurring at the broader scale of tissues, a difficult mathematical task known as multi-scale modeling. This innovative method, however, will help Gu integrate cell and tissue behaviors to better predict what is occurring during in-stent restenosis. This knowledge will help researchers improve prevention and treatment options, and help manufacturers design better stents.

            This multi-scale strategy also could be used to interpret other clinical observations, such as aortic aneurysm and traumatic brain injury.

            Gu also is eager to use her NSF award to recruit women and students from other underrepresented groups into the mechanical engineering field. She'll recruit graduate and undergraduate students, particularly women, to work on and learn from this project.

            "Because this research utilizes a mechanical principle to solve a biomedical problem, I hope to entice women into mechanical engineering," she said.

            Gu is also developing undergraduate curricula, preparing school-age presentations at the University of Nebraska State Museum about the relevance of engineering in solving medical problems, and is recruiting high school science teachers to work in her lab so they can share their research activities with students.

Writer: Gillian Klucas, Office of Research and Economic Development