There are a lot of news stories that the hard-working staff here at Spoiler Alerts have been following closely. These topics that warrant thoughtful columns that weave together current events, scholarly literature and hard-earned policy knowledge. The aim, as always, is to generate some useful scribblings that might help make the chaos of 2019 more recognizable to readers desperate for clarity. And I promise, those columns are coming.
First, however, I have to deal with the possibility of zombie pig brains and what that means for world politics.
If you have no idea what I am talking about, I would strongly suggest that you read Matthew Shaer’s New York Times Magazine cover story about the newfound ability to revive cellular activity in postmortem pig brains. Savvy readers will recall that this story first made waves three months ago when the research was published in a peer-reviewed Nature article and covered by NPR’s Nell Greenfieldboyce at the time. Here’s the paper abstract:
The brains of humans and other mammals are highly vulnerable to interruptions in blood flow and decreases in oxygen levels. Here we describe the restoration and maintenance of microcirculation and molecular and cellular functions of the intact pig brain under ex vivo normothermic conditions up to four hours post-mortem. We have developed an extracorporeal pulsatile-perfusion system and a haemoglobin-based, acellular, non-coagulative, echogenic, and cytoprotective perfusate that promotes recovery from anoxia, reduces reperfusion injury, prevents oedema, and metabolically supports the energy requirements of the brain. With this system, we observed preservation of cytoarchitecture; attenuation of cell death; and restoration of vascular dilatory and glial inflammatory responses, spontaneous synaptic activity, and active cerebral metabolism in the absence of global electrocorticographic activity. These findings demonstrate that under appropriate conditions the isolated, intact large mammalian brain possesses an underappreciated capacity for restoration of microcirculation and molecular and cellular activity after a prolonged post-mortem interval.
In English: It turns out that it is possible, with the right equipment, to revive some aspects of brain activity in large mammals — including human beings — after death.
Now there are a HECK of a lot of implications for this kind of research, and Shaer does an excellent job of describing both the science and the bioethics behind this paper. He focuses in particular on the lead author of the article, Yale neuroscience researcher Nenad Sestan.
Now as someone who has also published peer-reviewed research on the international implications of reanimating dead tissue, I can imagine all the questions you might have. Having read Shaer’s story carefully, I think there are a few important takeaways:
1. DON’T PANIC. As Sestan told Shaer, “When you let your imagination go berserk, when your mind wanders, you make mistakes.” So let us put a damper on everyone’s imagination and dissipate any concern about anything approximating zombies that you might possess. That’s not going to happen.
The technology that Sestan and his co-authors have developed is called “'ex vivo’ perfusion” — maintaining the necessary circulation of blood to preserve the functioning of organs detached from the body. The last four words of the previous sentence are super-important. Whatever is revived in these brains, they are not attached to anything that can move.
In other words, we are no longer talking about anything that resembles the zombie genre. We are now in an entirely different genre:
2. The backstory of some of this stuff is perfect horror-novel material. Again, to repeat: There is no chance of the zombie apocalypse occurring. That said, there are elements of this story that are, shall we say, evocative of “Dead Snow.” When Shaer wrote, “as long as scientists have understood the role of the mammalian brain, there have been efforts to reanimate it,” I really hope he was cackling maniacally, because that is a great opening to a horror novel. Here are some bits and pieces from the scientific history Shaer covers:
- The first effort to reanimate a large mammal’s brain was by physicist Giovanni Aldini. According to Shaer: “In his 1803 book, Aldini describes decapitating an ox and connecting the head to a rudimentary battery; almost immediately, the head began to violently shiver, as if undergoing some kind of seizure. Later, he moved on to humans. ‘The left eye actually opened,’ he wrote of the murderer George Forster, whose recently executed corpse was provided to him by the British government for experimentation.”
- The perfusion technology that Sestan builds on to do his research is relatively old. As Shaer notes, “The first perfusion pump [was] invented in the 1930s by the Nobel Prize-winning scientist and Nazi sympathizer Alexis Carrel and his close friend, the aviator Charles Lindbergh.”
So, to recap: This story of pig brain reanimation already contains one mad scientist and two Nazi sympathizers. That is some horror backstory gold right there.
3. All of the research to date has been done as ethically as possible. If there is one takeaway from the article, it is that Sestan is not a mad scientist. He made sure that his research stayed well within the ethical guidelines. His overriding concern was that his experiments would be so successful that they might reactivate sufficient brain activity to generate consciousness. At one point, in 2016, when it appeared that the experiments had the possibility of doing that, he shut everything down and consulted with bioethicists at Yale and the NIH’s Neuroethics Working Group. Only after he consulted with them and took additional precautions did the research begin again. It is impossible to read Shaer’s story and not be thankful that this is the guy leading this research.
4. There is a bioethics crisis brewing, but it won’t start in the United States. Sestan acted ethically. Whether every scientist will do so is another question entirely. Shaer writes, “Undoubtedly, a scientist with fewer scruples than Sestan, fewer moral qualms about human experimentation, will emerge. ‘Somebody will perfuse a dead human brain, and I think it will be in an unconventional setting, not necessarily in a pure research manner,’ [Stanford ethicist Hank] Greely told me. ‘It will be somebody with a lot of money, and he’ll find a scientist willing to do it.’”
The technological constraint is nonexistent. The tech that Sestan and his team developed is open-source; pig and human brains are not that different. And there are some pretty recent examples of Chinese researchers who went way beyond global norms on genetic editing. These norms are always subject to change. If other countries’ scientists go where Sestan clearly will not, the norms can change.
There is no need to worry about a zombie pig invasion. That is not happening. Still, these experiments raise a lot of troubling questions for bioethicists. And they better get to work, because it is all too easy to see how this kind of research might go horribly wrong.