Israeli scientists have successfully restored mobility in paralyzed mice by giving them a spinal cord implant and they believe that they are less than three years away from conducting clinical trials that could see mobility restored in humans with spinal cord injuries.
In what is being described as a “world-first” experiment, that took place at Tel Aviv University, a team of researchers engineered spinal cord tissue from human cells, implanted them in 15 mice with long-term paralysis resulting in 12 of the mice being able to walk normally.
The peer-reviewed research was published on Feb. 7 in the journal Advanced Science.
Prof. Tal Dvir, who is part of a research team at the Sagol Center for Regenerative Biotechnology told The Times of Israel, “If this works in humans, and we believe that it will, it can offer all paralyzed people hope that they may walk again,” adding that the researchers have opened talks with the American Food and Drug Administration (FDA) regarding conducting clinical trials.
While the mice received spinal implants from the cells of three people, once the innovation is deployed in humans, cells from the patient’s own body will be used.
Dvir says that this will “enable regeneration of the damaged tissue with no risk of rejection,” and the need to suppress the immune systems of recipients will be eliminated.
While some scientists have conducted experiments that use human-based stem cells that are then injected into the spinal cords of animals have enjoyed some success, the procedure developed by the Israeli team grows pieces of an actual spine, engineered from human cells, and then transplants them.
The procedure is unique because it has been successful in restoring mobility in long-paralyzed animals, as past stem cell studies have typically been limited to newly paralyzed animals.
“Realistically, most humans needing treatment will have been paralyzed for some time when treatment is wanted, so this is important,” said Dvir adding that, “In our experiment, we used both newly paralyzed and long-paralyzed mice. We had success with both, and expect the impact to work with humans who have been paralyzed for different amounts of time.”
Dvir said that the success rate in mice with chronic paralysis was 80 percent however that success rate increased to 100 percent in mice with short-term paralysis.
The process starts with a small biopsy from the belly. “We separate the fat cells from other materials such as collagen and sugars, and reprogram the cells using genetic engineering methods, so they can ‘become’ any cell in the body,” Dvir explained.
“We put the cells in a substance that we make from the non-cellular material from the fat tissue gathered in the biopsy, put the cells inside it for 30 days, and we mimic how a spinal cord develops in an embryo. This produces spinal cord micro-neuron tissue, which we transplant into animals that have been paralyzed for a long time,” Dvir said.
A company, Matricelf, has been created in order to facilitate the clinical trials which Dvir expects to happen within two and a half years. He said since the original experiments utilised human cells it means that the research is already at an advanced stage.
“We’ve been using human implants on the mice, not mice implants, which means we’re not going back to the beginning of research to move over to humans. Rather, we know how to prepare the implants for humans, which is what makes us optimistic we will move quickly to clinical trials,” he said.
Dvir’s team, including Lior Wertheim, Dr. Reuven Edri, and Dr. Yona Goldshmit, says that the new method has applications beyond spinal cord injuries and could be used to address a range of diseases including Parkinson’s disease, brain trauma, myocardial infarction, and age-related macular degeneration.