Implant mimicks spinal cord and brain membrane for long term spinal cord and brain repair

Researchers at the École Polytechnique Fédérale, in Lausanne, Switzerland, to design a soft, flexible electronic implant, which they say has the same ability to bend and stretch as dura mater, the membrane that surrounds the brain and spinal cord. The e-Dura implant developed by EPFL scientists can be applied directly to the spinal cord without causing damage and inflammation.

EPFL researcher’s neural implant can make paralyzed rats walk again. Soft and stretchable, it is the first of its kind that can be implanted directly on the spinal chord, without damaging it. Described in Science, this new generation device called e-Dura combines electrical and chemical stimulation.

The scientists, including Gregoire Courtine, have previously showed that implants can allow mice with spinal injuries to walk again. They did this by sending patterns of electrical shocks to the spinal cord via electrodes placed inside the spine. But the rigid wires ended up damaging the mice’s nervous systems.

EPFL scientists have managed to get rats walking on their own again using a combination of electrical and chemical stimulation. But applying this method to humans would require multifunctional implants that could be installed for long periods of time on the spinal cord without causing any tissue damage. This is precisely what the teams of professors Stéphanie Lacour and Grégoire Courtine have developed. Their e-Dura implant is designed specifically for implantation on the surface of the brain or spinal cord. The small device closely imitates the mechanical properties of living tissue, and can simultaneously deliver electric impulses and pharmacological substances. The risks of rejection and/or damage to the spinal cord have been drastically reduced.

Journal Science – Electronic dura mater for long-term multimodal neural interfaces

Journal Science – A soft approach kick-starts cybernetic implants

Flexible and stretchy, the implant developed at EPFL is placed beneath the dura mater, directly onto the spinal cord. Its elasticity and its potential for deformation are almost identical to the living tissue surrounding it. This reduces friction and inflammation to a minimum. When implanted into rats, the e-Dura prototype caused neither damage nor rejection, even after two months. More rigid traditional implants would have caused significant nerve tissue damage during this period of time.

The researchers tested the device prototype by applying their rehabilitation protocol — which combines electrical and chemical stimulation – to paralyzed rats. Not only did the implant prove its biocompatibility, but it also did its job perfectly, allowing the rats to regain the ability to walk on their own again after a few weeks of training.

“Our e-Dura implant can remain for a long period of time on the spinal cord or the cortex, precisely because it has the same mechanical properties as the dura mater itself. This opens up new therapeutic possibilities for patients suffering from neurological trauma or disorders, particularly individuals who have become paralyzed following spinal cord injury,” explains Lacour, co-author of the paper, and holder of EPFL’s Bertarelli Chair in Neuroprosthetic Technology.

“It’s the first neuronal surface implant designed from the start for long-term application. In order to build it, we had to combine expertise from a considerable number of areas,” explains Courtine, co-author and holder of EPFL’s IRP Chair in Spinal Cord Repair. “These include materials science, electronics, neuroscience, medicine, and algorithm programming. I don’t think there are many places in the world where one finds the level of interdisciplinary cooperation that exists in our Center for Neuroprosthetics.”

Courtine joined electrical engineer Stéphanie Lacour came up with a new implant they call “e-dura.” It’s made from soft silicone, stretchy gold wires, and rubbery electrodes flecked with platinum, as well as a microchannel through which the researchers were able to pump drugs.

The work builds on ongoing advances in flexible electronics. Other scientists have built patches that match the properties of the skin and include circuits, sensors, or even radios.

An implant made of silicone and gold wires is as stretchy as human tissue.

Rats get spinal cord repair with no long term tissue damage

Stretchable electronics are merging with a widening effort to invent new ways to send and receive signals from nerves. “People are pushing the limits because everyone wants to precisely interact with the brain and nervous system,” says Polina Anikeeva, a materials scientist at MIT who develops ultrathin fiber-optic threads as a different way of interfacing with neural tissue.

The reason metal or plastic electrodes eventually cause damage, or stop working, is that they cause compression and tissue damage. A stiff implant, even if it’s very thin, will still not stretch as the spinal cord does. “It slides against the tissue and causes a lot of inflammation,” says Lacour. “When you bend over to tie your shoelaces, the spinal cord stretches by several percent.”

They could overcome spinal injury in rats by wrapping it around the spinal cord and sending electrical signals to make the rodent’s hind legs move. They also pumped in chemicals to enhance the process. After two months, they saw few signs of tissue damage compared to conventional electrodes, which ended up causing an immune reaction and impairing the animal’s ability to move.

Abstract- Electronic dura mater for long-term multimodal neural interfaces

The mechanical mismatch between soft neural tissues and stiff neural implants hinders the long-term performance of implantable neuroprostheses. Here, we designed and fabricated soft neural implants with the shape and elasticity of dura mater, the protective membrane of the brain and spinal cord. The electronic dura mater, which we call e-dura, embeds interconnects, electrodes, and chemotrodes that sustain millions of mechanical stretch cycles, electrical stimulation pulses, and chemical injections. These integrated modalities enable multiple neuroprosthetic applications. The soft implants extracted cortical states in freely behaving animals for brain-machine interface and delivered electrochemical spinal neuromodulation that restored locomotion after paralyzing spinal cord injury.

Editors Summary – Mechanically soft neural implants

When implanting a material into the body, not only does it need the right functional properties, but it also needs to have mechanical properties that match the native tissue or organ. If the material is too soft, it will be mechanically degraded, and if it is too hard it may get covered with scar tissue or it may damage the surrounding tissues. Starting with a transparent silicone substrate, Minev et al. patterned microfluidic channels to allow for drug delivery, and soft platinum/silicone electrodes and stretchable gold interconnects for transmitting electrical excitations and transferring electrophysiological signals. In tests of spinal cord implants, the soft neural implants showed biointegration and functionality within the central nervous system.

45 pages of supplemental material – Electronic dura mater for long-term multimodal neural interfaces

A soft approach kick-starts cybernetic implants – Robert F. Service

When it comes to making cybernetic implants that aim to fuse electronics with biology, a soft touch works best. Researchers in the United States and Switzerland report this week that they were able to restore the ability of paralyzed rats to walk after implanting ultrasoft, pliable electrode arrays along their damaged spines. The soft implants were better able to match the animals’ natural movements without detaching from the neural tissue. The softness also helped the implants avoid triggering rejection by the immune system, which could either kill the animals or cause the surrounding tissues to wall off the implants, leaving them useless. In the future, such implants may help restore mobility in paralyzed patients or be used to treat neurological ailments, such as Parkinson’s disease and Tourette syndrome.

Possibility of full body rejuvenation path to longevity

Complete spinal cord repair would enable brute force life extension.

There is a genetic disease where no brain forms in the body.
So the donor body could be without a brain.
Pig-human hybrids could be the body donor sources. Want to have proper typing for the donor body.

So Alzheimers and dementia is defeatable.
Complete Spinal cord repair is achievable.
Further advanced robotic surgery for lower cost, more speed and precision.
Need to work out the immune system transfer so that anti-rejection drugs are not needed.
But if you are swapping out the entire body. The donor body immune system would be the one to go with.

Perfect the body transfer.

A person ages normally to say 67.
The donor body is produced starting when the person is 49.
They get a fresh body every 50 years.
Treat the brain for Alzheimers. Try to keep the brain fresh with a supply of neurons and stem cells.
The person would have a completely rejuvanated immune system, blood etc…

I think 2-4 body swaps could be achievable before the brain deteriorates too much (even with the neurons and the stem cells).

The brain may deteriorate less if it is living with a young body.

Voila 180-280 year lifespans.

Dick Cheney and foreign dictators and the wealthy who could afford a $3-20 million set of procedures every 50 years go this route in a few decades.

But as I said there are better and more elegant ways for radical life extension that are more complicated to explain.

Details on the technical aspects of body transplants are here

HEAVEN capitalizes on a minimally traumatic cut of the spinal cord using an ultra-sharp blade (very different from what occurs in the setting of clinical spinal cord injury, where gross, extensive damage and scarring is observed) followed within minutes by chemofusion (GEMINI). The surgery is performed under conditions of deep hypothermia for maximal protection of the neural tissue. Moreover, and equally important, the motoneuronal pools contained in the cord grey matter remain largely untouched and can be engaged by spinal cord stimulation, a technique that has recently shown itself capable of restoring at least some motor control in spinal injured subjects.

Surgical Neurological International – HEAVEN: The head anastomosis venture Project outline for the first human head transplantation with spinal linkage (GEMINI)

SOURCES – EFPL, Technology Review, Youtube, Journal Science

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