Keio University is poised to conduct the world’s first treatment of patients who have sustained spinal cord injuries using induced pluripotent stem cells, sources close to the matter said Tuesday.

If approved by the state, the private university plans to inject neural stem cells produced from iPS cells into four people aged 18 or older who were injured while playing sports or in traffic accidents, starting next year.

For the planned treatment, a team of Keio researchers led by Hideyuki Okano, a professor in the School of Medicine, will first create neural stem cells from iPS cells in storage at Kyoto University and then freeze them for preservation, the sources said.

When a patient is presented who has lost motor function or sensation due to damage to their spinal cord, the researchers will inject the neural stem cells to encourage nerve regeneration.

Researchers will aim to perform the treatment within four weeks of the patient’s injury — the period when the therapy is expected to be effective. It is not currently targeted at chronic-stage patients, or those who have had damage to the spinal cord for six months or longer. But the research team will also try to develop a treatment that is effective for such patients, the sources said.

Keio University gave a tentative endorsement for the treatment plan on Tuesday.

On Friday, Kyoto University said it had conducted the world’s first transplant of nerve cells created from iPS cells to treat Parkinson’s disease. The institution is also expected to begin a blood transfusion test using platelets created from stem cells to treat patients with aplastic anemia.

Among other applications of iPS cells for health treatments in Japan, the government-backed Riken institute conducted the world’s first transplant in 2014 of retina cells grown from stem cells to treat patients suffering from serious eye problems.

Osaka University is planning to transplant a heart muscle cell sheet derived from iPS cells into the hearts of patients suffering from serious heart failure.

Kyoto University’s Shinya Yamanaka won the Nobel Prize in physiology or medicine in 2012 for discovering iPS cells, which can grow into any type of body tissue and are seen as a promising tool for regenerative medicine and drug development.