San Francisco
BY training cells to grow in precise patterns, researchers have come one step
closer to growing complex tissues such as nerves or blood vessels in the
laboratory. Their ideas could also pave the way for living electronic
circuits.
Most cells will only grow attached to a surface, so George Whitesides and
colleagues at Harvard University generated a pattern of sticky and unsticky
surfaces for the cells they were studying. They hoped that the cells would only
grow on the sticky surfaces. Using a tiny rubber stamp cast from a silicon chip,
the researchers made a repeating pattern of plateaus and valleys in clear
plastic. A flat stamp spread the sticky material on the plateaus, and the
plastic was dipped in a repellent material to coat the valleys.
Advertisement
Cells encouraged to grow on this terrain unswervingly chose the plateaus,
even when the sticky areas were only a single cell wide (Proceedings of the
National Academy of Sciences, vol 93, p 10775). If the sticky and repellent
materials were swapped the cells chose the valleys instead.
The potential applications are numerous. 鈥淚f you help cells to align like
this you can make something that begins to look like a nerve or a capillary,鈥�
says Whitesides. And nerve cells trained to grow in complex patterns could be
linked to conventional electronics to make hybrid circuits. 鈥淏eing able to
manipulate where cells go is very important,鈥� says Jeffrey Hubbell of the
California Institute of Technology in Pasadena.
He believes this system could help overcome the body鈥檚 tendency to form scars
around implanted medical devices. Scarring could be reduced if the implant鈥檚
surface texture encouraged blood vessels to grow towards it. 鈥淭his system has
the potential to change the way we make medical devices,鈥� he says.
