Last year, the renegade Italian neurosurgeon Sergio Canavero garnered international attention by announcing his intent to perform a human head transplant in 2017. Now he claims that a head transplant has been recently performed on a monkey and that mice with severed spinal cords are capable of moving their limbs. While Canavero suggests that head transplants could offer hope to people who are paralyzed, skeptics question his approach.
|Chinese researchers have announced that the second successful monkey head transplant has been performed.|
Frankenstein-like head transplants are possible, insists Sergio Canavero. "It's important that people stop thinking this is impossible. This is absolutely possible and we're working towards it," he recently told New Scientist.
In an unorthodox move, he has announced the success of the research before publishing research papers on the subject. He explains, however, that seven papers are forthcoming, and will be published this year in the journals Surgery andCNS Neuroscience & Therapeutics.
The doctor has been working with researchers in China and South Korea and has announced success in procedures with animals including monkeys and mice (see video below).
Canavero has released some information purported to support his claims. He suggests that a recent image released by researcher Xiaoping Ren of Harbin Medical University, China, demonstrate that a head transplant performed on a monkey was successful. The blood supply between the head and the monkey worked, but the researchers did not seek to connect the spinal cord in the monkey.
A similar experiment was performed by the controversial neurosurgeon Robert White in 1970, who termed the procedure a "full body transplant." He hoped the procedure would offer hope to patients suffering from severe organ failure and other terminal conditions.
Canavero states that the recent procedure confirms that if the head is cooled to a temperature of 15°C, a monkey can survive the ordeal "without any neurological injury of whatever kind." The monkey was ultimately put to sleep within 20 hours of the procedure for ethical reasons.
The video footage released by Canavero include a scene showing mice moving its legs reportedly weeks after their spinal cord had been severed and then reattached.
These include the video above of mice sniffing and moving their legs, apparently weeks after having the spinal cord in their necks severed and then re-fused. Released by C-Yoon Kim, at Konkuk University School of Medicine in South Korea, the video could hint that restoring motor function in animals' limbs is possible after the spinal cord has been entirely severed.
The breakthrough was made possible through the use of the chemical polyethylene glycol, a widely used chemical that is found in everything from toothpaste to rocket fuel.
Canavero suggest that the chemical can be used to preserve nerve cell membranes when cutting the spinal cord.
A number of scientists remain unconvinced, as least as the amount of data about the results is thin."It's science through public relations," quipped Arthur Caplan, a bioethicist at New York University School of Medicine to New Scientist.
In a related vein, JAMA last year publishing an op-ed specifically questioning what the journal called stealth science, which specifically mentioned Theranos' boasts that it had disrupted blood diagnostics while sharing practically no data to back up those claims.
In the meantime, the Chinese researchers work continues with backing from the Chinese government.
In addition, Canavero has found a volunteer to attempt to be the first recipient of a head transplant, the 31-year-old Russian patient Valery Spiridonov, who suffers from Werdnig-Hoffman disease, which is also known as type 1 spinal muscular atrophy. In addition, the director of Vietnam-Germany Hospital in Hanoi, Vietnam has volunteered to host the procedure.
While Canavero is running into skepticism from peers, some prominent scientists remain open to the idea, including Michael Sarr, editor of the journal Surgery who states that editors of the journal are interested in head transplantation as a proof of principle despite ethical problems associated with the procedure.