SHANGHAI - Chinese scientists are celebrating a breakthrough in the treatment of lung disease that enables patients with damaged respiratory organs to breathe normally.

Regenerative medicine specialists at Tongji University and doctors at the university's affiliated Shanghai Oriental Hospital have successfully transplanted adult stem cells to reconstitute a patient's injured lung.

The stem cells are taken from the patient's airway and expanded millions of times in vivo before the transplantation. After three to six months, they grow new alveoli and bronchi that improve lung function.

The achievement of the research team led by Professor Zuo Wei was published in the latest issue of "Protein and Cell" as cover story.

A 67-year-old patient was one of first to have been treated in this way. Two years ago, he was diagnosed with pulmonary fibrosis, a respiratory disease in which scars are formed in the lung tissues, leading to serious shortness of breath. Today his breathing is much improved.

Pulmonary fibrosis is characterized by irreversible and progressive damage to lung tissue, said Zuo. "Drugs have little effect and lung transplants used to be the only solution."

However, organ transplants are limited by a lack of donors. In 2017, only 299 lung transplants were performed in 20 Chinese hospitals.

Lung disease is the third-leading cause of deaths globally and 11 percent of Chinese people over the age of 40 suffer from some lung condition.

After two years of experiments on mice, researchers found that stem cells from airway epithelia were more successful than others.

Zuo compares the stem cells to "seeds".

"We sow the 'seeds' to the injury site, allow them to grow for a few months and gradually to rehabilitate the damaged organs."

Over the past two years, more than 80 lung patients across China have had stem cell transplants.

"The regenerative technology is amazing and a promising cure for many chronic lung diseases," said Xu Jinfu, chief doctor of Shanghai Pulmonary Hospital.

Though it is still in its infancy, Zuo has a lot of confidence in regenerative medicine, saying his team is studying liver, kidney and uterus regeneration.

"I am glad to see many patients recovering and returning to normal lives. Millions of patients are in urgent need of a new treatment. Regenerative therapy is likely to be the biggest hope for them."