MD-PhD student starts nanotechnology company

Lead product is surgical mesh made of nanofibers

Matthew MacEwan
Washington University MD-PhD student Matthew MacEwan recently started his own nanotechnology company, NanoMed LLC, which is developing a synthetic polymer surgical mesh made of individual strands of nanofibers.

Matthew MacEwan is no ordinary medical student.

The neurosurgeon-to-be, a student at Washington University School of Medicine in St. Louis, also is pursuing a doctorate in biomedical engineering. And at 29, he recently started his own company, NanoMed LLC, aimed at revolutionizing the surgical mesh used in operating rooms worldwide.

The lead product, invented by MacEwan and Jingwei Xie, PhD, a former postdoctoral researcher in engineering, is a synthetic polymer mesh made of individual strands of nanofibers. The mesh was developed to repair injuries to the brain and spinal cord but could also be used to mend hernias, fistulas or other injuries.

The nanofiber material has the potential to make operations easier for surgeons to perform. For patients, the mesh could lead to fewer complications after surgery because it naturally breaks down over time.

Existing surgical mesh used to repair the protective membrane that covers the brain and spinal cord is thick and stiff, making it difficult to work with. But the novel material MacEwan and Xie developed is thin and flexible and more likely to integrate with the body’s own tissues.

“It’s almost like a cloth,” MacEwan says. “But it’s designed on a nanoscopic scale. To put that into perspective, every thread of the mesh is thousands of times smaller than the diameter of a single cell.”

The technology’s promise has caught the attention of the business world. In 2011, MacEwan won the prestigious Olin Cup, sponsored by Washington University’s Skandalaris Center for Entrepreneurial Studies. The business plan competition recognizes startups with a high probability of success.

Then in June, he won the Licensing Executives Society Foundation’s International Graduate Student competition in London, and in November, the Idea to Product Global Competition in Stockholm. The winnings of more than $100,000, along with other investments and in-kind services, have helped MacEwan get the company off the ground.

“It’s incredibly exciting to see a product we developed make its way to the commercial market,” MacEwan says.

The nanofiber material was developed in Washington University laboratories by MacEwan and Xie, now a senior scientist at Marshall University in West Virginia, along with collaborators Younan Xia, PhD, the James M. McKelvey Professor of Biomedical Engineering, and Zack Ray, MD, now a neurosurgical fellow at the University of Utah. MacEwan has worked closely with the university’s Office of Technology Management, which has filed patents on the technology.

Fibroblasts (in bright blue), the cells that cover the surfaces of the intestine and other organs, grow along nanofabricated surgical mesh designed in a starburst pattern. The individual nanofibers originate from a central point and radiate outward, encouraging cells to migrate and grow toward the center for a wound.

Currently, many surgical meshes are derived from pig or cow skin. These tissues must be chemically treated and processed so that they can be left in the body. As a result, the meshes can be rigid and bulky, and difficult to shape to the convoluted surface of the human brain.

In contrast, the nanofiber material MacEwan developed is organized on a size scale familiar to cells and replicates their natural environment.

“We’ve taken the whole idea of surgical mesh and pushed it into a new direction,” MacEwan says. “It’s not just a foreign material you’re putting into the body. The nanofabricated nature of the mesh creates a scaffold that cells can easily penetrate and populate to recapitulate the body’s tissues.”

The surgical mesh looks like gauze but feels sticky, like a spider web. It is typically composed of multiple layers of nanofibers and can be cut to size for different uses. Once the mesh is placed in the body, cells grow along the individual nanofibers, which gradually degrade in nine to 12 months, leaving the body’s own tissue in its place.

One advantage of the new technology is that different patterns of nanofibers can be created in the mesh to promote the healing of different kinds of wounds. For example, in a starburst pattern used to repair ulcers and other circular wounds, the nanofibers originate from a central point and radiate outward. This encourages cells to migrate and grow toward the center of the wound.

For linear defects like tears and incisions, nanofibers can be aligned perpendicular to the wound, encouraging cell growth across the injury, which provides reinforcement to the new tissues.

“We can really manipulate and change the design of the material to optimize it for specific clinical uses and applications,” MacEwan says.

MacEwan is now evaluating the product in animal models, a first step toward gaining U.S. Food and Drug Administration approval. Preliminary studies indicate the nanofiber material is safe and effective. MacEwan is hopeful that clinical trials in patients will begin later this year.

NanoMed LLC is based in St. Louis. In November, Agnes Rey-Giraud, a former executive and board member at Express Scripts, joined the company to head business development.

For now, MacEwan is finishing his doctorate and has two years left before he receives his medical degree. He’s planning a career in academic medicine, where he can spend time in the laboratory and the operating room. There, he hopes to use the nanofiber surgical meshes he developed to improve the care and surgical outcomes of his own patients.

“At Washington University, I have continually focused on moving discoveries beyond the laboratory,” MacEwan says. “I hope to see this technology have a positive impact on many patients. Nothing would be more thrilling to me.”

Washington University School of Medicine’s 2,100 employed and volunteer faculty physicians also are the medical staff of Barnes-Jewish and St. Louis Children’s hospitals. The School of Medicine is one of the leading medical research, teaching and patient care institutions in the nation, currently ranked fourth in the nation by U.S. News & World Report. Through its affiliations with Barnes-Jewish and St. Louis Children’s hospitals, the School of Medicine is linked to BJC HealthCare.