Photo by Thomas Griffin

Building Better Body Parts

Jan Stegemann is a biological architect of sorts. The Rensselaer assistant professor of biomedical engineering is building better three-dimensional scaffolds of naturally derived polymers. The goal is to create bioengineered tissues capable of replacing damaged body parts, such as blood vessels, or eventually entire organs, such as the pancreas and liver.

Polymers that exist in nature, such as agarose, alginate, collagen, and fibrin, have been used widely in tissue engineering applications. A more complete understanding of the structure of these different matrices, how they interact with cells, and how they affect cell function would benefit a variety of fields in biotechnology.

“You must first have the proper scaffold, or foundation, or the entire structure will be affected,” says Stegemann, who spent five years at Grace Biomedical in Massachusetts developing cell-based bioartificial organs. “We are working to understand and build foundations that will lead to fully functional tissues.”

Stegemann is mimicking the complex set of biochemical and mechanical signals that affect cell function in the body. Using the right combination of signals, he can control cell function to better engineer tissue.

He is developing a blood vessel composed of isolated vascular smooth muscle cells embedded in a matrix of collagen and fibrin to study how the functions of cells change when they are removed from their native environment. Defining these extracellular environments can help in understanding the mechanisms that lead to vascular diseases—such as hypertension—and could prevent or reverse the disease.