Thaindian News

Washington, May 17 (IANS) Tissue engineering has long held promise for building new organs to replace damaged livers, blood vessels and other body parts. However, a major obstacle is getting cells grown in a lab dish to form 3-D shapes instead of flat layers. Scientists have now come up with a new way to overcome this challenge.
Researchers at the MIT-Harvard Division of Health Sciences and Technology (HST) are encapsulating live cells in cubes and arranging them into 3-D structures, just as a child would construct buildings out of blocks.

The new technique, dubbed “micromasonry,” employs a gel-like material that acts like concrete, binding the cell “bricks” together as it hardens.

The research was conducted by Ali Khademhosseini, assistant professor of HST, and former HST postdoctoral associate Javier Gomez Fernandez.

The tiny cell bricks hold potential for building artificial tissue or other types of medical devices, says Jennifer Elisseeff, associate professor of biomedical engineering at Johns Hopkins University, who was not involved in the research.

“They’re very elegant and have a lot of flexibility in how you grow them,” she says. “It’s very creative.”

To obtain single cells for tissue engineering, researchers have to first break tissue apart, using enzymes that digest the extracellular material that normally holds cells together.

However, once the cells are free, it’s difficult to assemble them into structures that mimic natural tissue microarchitecture.

Some scientists have successfully built simple tissues such as skin, cartilage or bladder on biodegradable foam scaffolds.

“That works, but it often lacks a controlled microarchitecture,” says Khademhosseini. “You don’t get tissues with the same complexity as normal tissues.”

For instance, Fernandez and Khademhosseini built tubes that could function as capillaries, potentially helping to overcome one of the most persistent problems with engineered organs — lack of an immediate blood supply, said a Harvard release.

“If you build an organ, but you can’t provide nutrients, it is going to die,” says Fernandez, now a postdoctoral fellow at Harvard. They hope their work could also lead to a new way to make artificial liver or cardiac tissue.

These findings have been published online in Advanced Materials.