China experts develop shells to preserve cells longer

By Tan Ee Lyn

HONG KONG (Reuters) - Scientists in China have developed "shells" that can wrap around living cells and preserve them, and hope to use the technique in cell transplants to repair damaged human tissues and to battle cancer.

In the journal Angewandte Chemie, the researchers described how they grew these artificial shells around yeast cells. The mineral coating kept more than 80 percent of the yeast cells alive after a month at room temperature.

Unclothed yeast cells die way before a month is up.

"This coating is made of calcium phosphate, (the material in) bone and tooth in mammals. It is biologically compatible and living cells would still be alive after getting the coating," said Tang Ruikang at the Zhejiang University in eastern China.

"The function of the shell is very close to clothes that we wear. The clothes can't change the nature of the human, but they can protect us," he said in a telephone interview.

Tang's team was inspired by the simplicity of eggshells; how a single cell was protected by a thin mineral layer.

Using synthetic molecules which acted as scaffolding, they managed to grow calcium phosphate around yeast cells.

Looking ahead, Tang wants to grow these shells around living human cells, before implanting them into damaged bones or other human tissues to repair them.

"When we implant cells into bones, the cells must be kept at very low temperatures, but with this technique we can wrap the cells and keep them alive for a long time in room temperature and then implant them into the living system," Tang said.

Tang hopes the technique may one day be used to kill cancer cells.

"We can also wrap viruses and deliver them into cancer cells. Cancer cells love to eat calcium phosphate and once the shells are broken down, the viruses are released and they can eat up cancer cells," Tang said.

(Editing by Valerie Lee)