Rebuilding The Human Body

In Tufts’ Tissue Engineering Resource Center, director and biomedical engineering chair David Kaplan is figuring out how the human body is put together, one cell at a time.

Medford/Somerville, Mass. [11.19.04] In his Tufts laboratory, David Kaplan sorts tirelessly through the glue and the building blocks that make the human body stick together – and he is having a blast doing it.

"Any of us can clone or express a gene – that's not hard anymore,” Kaplan told The Boston Globe. “What's interesting is how you get this incredibly complicated architecture that lets us live and breathe and run around and have fun."

Kaplan, who is the director of the the University’s new Tissue Engineering Resource Center as well as the chairman of the Department of Biomedical Engineering, concentrates on finding practical uses for his research rather than maintaining a purely academic perspective.

"There are so many cool things," he said to the Globe, which profiled his work on Monday.

Kaplan told the newspaper that he became interested in this sort of research when he was doing graduate work at Syracuse University on lignin, the protein that strengthens wood.

"I was fascinated by the combination of enzymes that produces this complex glue that makes trees stand up," he explained to the Globe.

Subsequently, he became interested in the surprisingly hardy strength of spider silk, which he later determined was due to the way spiders stretch and dry the polymers they produce.

Besides silk-spinning and tree-growing, Kaplan has also studied what makes barnacles cling to rocks, the organization of bone and tendon cells and the aging of adult stem cells in an attempt to better understand how cellular framework is established.

Despite the lack of comprehensive understanding of these processes, the prospects for discovery excite Kaplan.

"If you're not afraid of learning, it's wonderful," he said to the Globe.

Kaplan explained to the Globe how silk, for instance, can be used as a support structure upon which adult stem cells can convert into bone, tendon, muscle or cartilage.

Cellular development is then cultivated with rich helpings of nutrients and oxygen and careful manipulation of the cells’ shape and position.

Some of the center’s discoveries may eventually lead to the development of a replacement for the anterior cruciate ligament (ACL) as well as treatments for people suffering from arthritis, cancer and osteoporosis.

Kaplan is a big believer in cross-disciplinary learning, citing the energy and knowledge he draws from colleagues across the fields of computer science, physics and engineering.

"Future advances are going to have to be at the interface of disciplines," he told the Globe.

With a $4 million grant from the National Institutes of Health, Kaplan founded the center in September in conjunction with MIT’s Gordana Vunjak-Novakovic, who also has an adjunct teaching position at Tufts’ School of Engineering.

Kaplan attributes much of his success to the work of his colleagues.

"I'm surrounded by great people," he explained to the Globe. "It makes my life tolerable."

Alongside the center’s research, the center works on tissue engineering with local biotechnology companies.

One such company, Tissue Regeneration Inc. of Medford, is run by a former student of Kaplan’s, Tufts assistant research professor in biomedical engineering Greg Altman, who is eyeing human trials of replacement knee ligaments within two years.

With so many mysteries of the human body yet to be unraveled, Kaplan is undaunted – even encouraged.

"We know nothing," he remarked to the Globe. "It's fantastic."