New York: Scientists have created the first engineered living human nervous tissue constructs which they claim could be used for transplants to repair damage to the nervous system.
“We have created a three-dimensional neural network, a mini-nervous system in culture, which can be transplanted en masse,” according to lead researcher Prof Douglas H Smith of the University of Pennsylvania.
The team obtained human dorsal root ganglia neurons (clusters of nerves just outside the spinal cord) to engineer into transplantable nervous tissue. The neurons were harvested from 16 patients following elective ganglionectomies and four thoracic neurons were harvested from organ donors.
Subsequently, the neurons were purified and placed in a specially designed growth chamber. Using the stretch growth technique, the axons were slowly pulled in opposite directions over a series of days until they reached a desired length.
The neurons survived at least three months in culture while maintaining the ability to generate action potentials, the electrical signals transmitted along nerve fibres. The team found that the axons grew at about one millimetre per day to a length of one centimetre.
“This study demonstrates the promise of adult neurons as an alternative transplant material due to their viability, availability and capacity to be engineered.
“We’ve also shown the feasibility of obtaining neurons from living patients as a source of neurons for autologous, or self, transplant as well as from organ donors for allografts,” Prof Smith was quoted by the ScienceDaily as saying.
The results of their study have been reported in the latest edition of the Journal of Neurosurgery.
In their previous work on rodents, the group had showed that they could induce tracts of nerve fibres called axons to grow in response to mechanical tension.