Jerusalem, Feb 13 (IANS): Researchers at Tel Aviv University in Israel have engineered 3D human spinal cord tissues and implanted them in a lab model with long-term chronic paralysis.
The scientific breakthrough, with an approximately 80 per cent success rate in restoring walking abilities, may enable people with paralysis to walk again, said the researchers.
The team led by Prof Tal Dvir from Sagol Center for Regenerative Biotechnology at the varsity, is now preparing for the clinical trials in human patients.
The technology, published in the scientific journal Advanced Science, is based on taking a small biopsy of belly fat tissue from the patient.
This tissue, like all tissues in our body, consists of cells together with an extracellular matrix (comprising substances like collagens and sugars). After separating the cells from the extracellular matrix, the team used genetic engineering to reprogramme the cells, reverting them to a state that resembles embryonic stem cells -- namely cells capable of becoming any type of cell in the body.
From the extracellular matrix, they produced a personalised hydrogel that would evoke no immune response or rejection after implantation.
"We then encapsulated the stem cells in the hydrogel and in a process that mimics the embryonic development of the spinal cord, we turned the cells into 3D implants of neuronal networks containing motor neurons," Dvir said.
The human spinal cord implants were then implanted in lab models, divided into two groups: those who had only recently been paralysed (the acute model) and those who had been paralysed for a long time - equivalent to a year in human terms (the chronic model).
Following the implantation, 100 per cent of the lab models with acute paralysis and 80 per cent of those with chronic paralysis regained their ability to walk.
"The model animals underwent a rapid rehabilitation process, at the end of which they could walk quite well. This is the first instance in the world in which implanted engineered human tissues have generated recovery in an animal model for long-term chronic paralysis - which is the most relevant model for paralysis treatments in humans," Dvir said.