"The clinical practice of this scientific research is a big step in the area of the construction of human tissues and organs," said Professor Cao Yilin, director of the Shanghai Tissue Engineering Centre, Monday.

A local seven-year-old boy lost one-sixth of his skull when a 6-square-centimetre area was badly damaged in a traffic accident in April 2001.

The injured area was too large to use the traditional method of plastic surgery, under which the damage would have been repaired by a piece of bone cut from another part of the body. So, surgeons at Shanghai No 9 People's Hospital, affiliated to Shanghai Second Medical University, turned to tissue-engineered bone, which they attached to the boy's skull five months ago.

Scientists took a small amount of the boy's bone-marrow cells and isolated the stem cells, which were then used to cultivate bone cells. Then the cells expanded to the required size in a framework made by biological materials that are well absorbed by human bodies. Cao refused to specify which biological materials were used.

Cao said: "In the past five months, the tissue-engineered bone has grown well and become part of the child's skull. There will be no infection or rejection."

Tissue engineering combines cell biology and material engineering. It focuses on research into and the development of biological substitutes to repair or rebuild injured or diseased tissues or organs. Unlike cloning technology, which duplicates DNA, the principle of tissue-engineering science is to reproduce tissue cells and is of great value for wide clinical practice.

Based on these principles, Cao's laboratory has applied the technique to rebuilding different kinds of tissue, including bones, cartilage, tendons, skin and corneas etc.

(China Daily December 31, 2002)