Chinese researchers have found and isolated a rare group of adult stem cells from mature tissues.

The group of stem cells is considered valuable because it may serve as the natural "repair" tool for worn, damaged or diseased tissues ranging from fetal pancreas bone marrow to liver, skin and skeletal muscle.

Dr Zhao Chunhua, who heads the newly founded Center of Excellence in Tissue Engineering in Beijing, detailed the findings at the second International Symposium on Stem Cell Research in Beijing last week.

The group of adult stem cells helps replenish not only damaged tissues they reside in, but also other damaged tissues through triggered migration, said Zhao, whose center is an affiliate of the Chinese Academy of Medical Sciences and Peking Union Medical Collage.

The symposium is an annual event that brings together medical scientists from China and around the world to discuss current issues and progress on stem cell research.

This year, participants focused on understanding of the fundamental mechanisms of stem cells and their therapeutic applications.

The theme followed several worldwide advances in stem cell research.

According to Nature magazine, the field has been "transformed" as scientists have achieved successes in "culturing human embryonic stem cells," piecing together the puzzles for every tissue in human beings and "in manipulating their differentiation in vitro."

"Stem cell research will change medicine significantly," said Dr Harald Neumann, the group leader of the Neuroimmunology Unit of European Neuroscience Institute in Germany, in an interview with China Daily.

"It provides a new approach to cure many diseases."

Dr Mariusz Ratajczak, director of Stem Cell Biology Program at James Graham Brown Cancer Center at the University of Louisville in the United States, agreed.

"Therapeutic applications of stem cells will definitely be the future as it will improve the quality of life for future generations," Ratajczak said.

Blood-forming stem cells -- vital elements in bone marrow transplants -- have already been used extensively in treating several types of leukemia.

Now stem cells also offer hope as a renewable source of replacement cells and tissue to treat myriad diseases, conditions and ranging from Parkinson's and Alzheimer's to spinal cord injuries, strokes, burns, heart disease, diabetes, osteoarthritis and rheumatoid arthritis.

In China, doctors have already conducted the clinical transplants of bone marrow stem cells to treat acute heart infarction.

"A lot of clinical trials are being carried out, making further progress in stem cell research and therapies," said Professor Liu Depei, president of Chinese Academy of Medical Sciences and Peking Union Medical College.

Zhao and his colleagues first announced their findings at the 32nd Annual Meeting of the International Society for Experimental Hematology held in Paris in July.

Zhao said his group is using adult stem cells as seed cells in tissue engineering and will start clinical trials next year.

Zhao emphasized that he and his colleagues focus on adult stem cells and isolate them from mature tissue, regardless of the age of the donor, so that the patients themselves will get treatment via transplantation of their own stem cells.

"We are currently focusing on growing adult stem cells for blood diseases, heart diseases, acute hepatic failure and diabetes," said Zhao.

They are applying for approval from the State Food and Drug Administration in China.

Zhao said Chinese researchers have won encouraging support from the central government.

Many Chinese scientists studying and working in the United States, Germany and elsewhere are returning home for the new opportunity.

"I am one of them," said Zhao, who has worked for several years on stem cells as an assistant professor under the leadership of Dr Catherine Verfaillie, director of the Stem Cell Institute at the University of Minnesota in Minneapolis of the United States.

This year, Zhao's group has received high-technology research funding from the Ministry of Science and Technology after fierce competition.

"Stem cell research is at its knowledge acquisition and experiment phases, and more studies are required to elucidate the mechanisms prior to the actual clinical application," commented Dr Neumann.

"Currently there is no standard protocol for performing the therapy, and a lot more work needs to be done.

"We have done many preclinical studies and prepared to launch clinical trials with very strict protocols that we have devised," Zhao said.

"China is one of the leading countries in stem cell research," said Dr Ratajczak.

(China Daily December 26, 2003)