Regenesis (23 page)

That trick may help get us to other planets. Meanwhile, back here on earth we continue to suffer from thousands of diseases, including rabies.

In 2004, when Jeanna Giese entered the Children's Hospital of Wisconsin, a team of eight physicians headed by Rodney E. Willoughby consulted with Jeanna's parents about possible courses of treatment. They proposed an aggressive approach based on an untested strategy that might ultimately fail. Even if the patient were to survive, they said, she might wind up severely disabled. With essentially no other alternatives, Jeanna's parents told them to go ahead.

They planned to induce a coma to put Jeanna's central nervous system on hold and protect the brain from injury while the patient's body mounted a native immune response to the virus. In addition they would administer one of the few antiviral drugs in existence, ribavirin, along with a cocktail of sedatives to maintain the coma and ensure suppression of the nervous system.

A week into the treatment, a lumbar puncture revealed an increase of rabies-specific antibody in both the bloodstream and the cerebrospinal fluid. Gradually the patient was brought out of the coma. After about two weeks of treatment, Jeanna blinked, opened her eyes, and moved them. Two days later she raised her eyebrows in response to speech. “On the 19th day,” according to the report published in the
New England Journal of Medicine
, “she wiggled her toes and squeezed hands in response to commands, [and] fixed her gaze preferentially on her mother.” Some nervous system abnormalities developed as she was brought back to full conscious awareness, but she continued to progress.

“Given her continued neutralizing antibody response to rabies virus in the cerebrospinal fluid and blood, and our inability to isolate the virus or detect viral nucleic acid in saliva, the patient was considered cleared of
transmissible rabies and removed from isolation on the 31st day.” A month later, she was released from the hospital.
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Jeanna eventually returned to school and had no difficulties with learning or memory, although she still suffered some weakness in her left hand and foot, and walked with a lurching gait. Today, eight years after being bitten by a rabid bat, Jeanna Giese appears in more than a dozen videos on YouTube, in which she looks and sounds healthy and pleasant. She even has her own website: jeannagiese.com.

Her experience is a case study in the powers and limitations of the human immune system. She was one of only two survivors out of twenty-five attempts at using the first Milwaukee (or Wisconsin) protocol, as Willoughby's pioneering procedure is now known, and two out of ten in the revised version. Plainly there is ample room for improvement. If synthetic genomics were used to enhance our immune response, we would possess a deliberately engineered superimmunity to a vast array of diseases. This would represent a fundamental advance over the immune systems that we were natively endowed with, and which were born during the Paleocene.

Today's cutting-edge practice as applied to Jeanna Giese might one day seem incremental and brutal as we look back on the remarkable alternatives described in this chapter. All the more reason to embrace them.

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In June 2011, an eight-year-old California girl became the third person in the United States known to have recovered from rabies infection through the use of the Wisconsin protocol by a team of physicians, nurses, and therapists at UC Davis Children's Hospital.

Engineering Extinct Genomes

When people think about extinct species such as the dodo, the passenger pigeon, or Tyrannosaurus Rex, what often comes to mind is the old adage, “Extinction is forever.” Only it isn't. As we have seen, one member of an extinct species has already been brought back to life, albeit briefly, and it wasn't even through genomic engineering.

The Pyrenean ibex is a type of mountain goat also known as the bucardo. When they were still in existence, bucardos were one of Europe's most striking wild animals, with handsome faces, distinctive curving horns, and short, thick wool. They roamed all over the Pyrenees mountain range along the border between Spain and France. But during the late nineteenth century they were massively hunted, and by 1900 fewer than one hundred of the animals were left. The Spanish Ministry of Environment confined a small remaining population of forty bucardos to Ordesa National Park, a spectacular mountainous region in Huesca province.

In 1993 only ten individuals were left, and by 1999 there was only one, a twelve-year-old female named Celia. In the spring of that year, two biologists at the Center for Agro-Nutrition Research and Technology in Aragon, Jose Folch and Alberto Fernández-Árias, captured Celia, took a
tissue scraping from her ear for the purpose of preserving the bucardo cell line, and put a radio-tracking collar around her neck. In the laboratory, the researchers multiplied the cells and then stored them away for safe-keeping in liquid nitrogen. Less than a year later, on January 6, 2000, Celia died.

According to the conventional wisdom, that should have been the end of the matter; one more species gone forever. But Folch and Fernández-Árias had a plan for bringing the animal back through a process known as nuclear transfer cloning. Nuclear transfer cloning was the same technology that gave us the first cloned mammal, Dolly the sheep, in 1996. In an ironic twist of fate, Dolly had not been cloned from the cells of a living sheep. Rather, she had been produced from a frozen udder cell of a six-year-old ewe that had died three years prior to Dolly's birth. Dolly had been literally raised from the dead. But if a live sheep can be cloned from a dead one, then why not a mountain goat? It made no difference to the frozen cells that they happened to be the last of the line: cells were cells, and so long as they contained intact DNA and the other normal structures within the cell nucleus, then they ought to be acceptable candidates for cloning.

Nuclear transfer cloning was still in its infancy, with many more failures than successes. Conceptually, the process was simple enough: take the nucleus from a cell of the animal to be cloned, transfer it to an embryonic cell from which the nucleus had been removed (an “enucleated” cell), and then implant that newly re-nucleated embryonic cell into the uterus of a surrogate mother. In theory, supposing that neither the recipient cell's cytoplasm or other organelles, nor the transferred nucleus itself, were damaged in the process, the procedure ought to work. In practice, it mostly didn't in the first few experimental trials. Apparently the process of disrupting cells in this gross manner often injured them beyond repair.

The first animal to be cloned by nuclear transfer was a northern leopard frog, produced at a research institute in Philadelphia in 1951 by experimenters Robert Briggs and Thomas J. King. They moved the relatively large DNA-bearing nuclei into the large frog eggs with a simple hollow glass pipette. During their first few attempts, the implanted embryonic
cells withered and died. But the researchers persisted, and over the course of 197 attempts, Briggs and King were able to turn out twenty-seven tiny tadpole clones.

Forty-five years later, anyone might think that the nuclear transplantation batting averages would have improved. In fact, the reverse was true. When Ian Wilmut tried to clone the first sheep from an adult mammalian cell, he started out with an initial pool of 277 mammary gland (udder) cells taken from a six-year-old Finn Dorset ewe. Those 277 cells yielded up only twenty-nine embryos. Those twenty-nine embryos were transferred into the uteruses of Scottish blackface ewes—the recipient surrogate mothers. This resulted in only thirteen pregnancies. And out of the thirteen, only one cloned little lamb was born, Dolly.

So when Jose Folch, Alberto Fernández-Árias, and an international team of experts tried to clone the extinct Pyrenean ibex, they had no illusions about their prospects for success. Indeed, they were well prepared for the series of failures that they experienced. For one thing, Celia had been the last of the species, which meant that the surrogate mothers would be of a different species than Celia. That constituted no insuperable barrier, however, because interspecies nuclear transfer cloning was already a going concern. In 2001, for example, a common domestic cow was successfully used as a surrogate mother for the cloning of a wild ox. Domestic dogs have been used as surrogate mothers for gray wolf clones (although it took 372 embryos to get three live wolves), and so on.

On a date that has never been reported in the scientific literature or in news accounts, and that we here disclose for the first time, the experimenters began their first species regeneration attempts, their so-called Experiment One, in the fall of 2002.
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First they had to turn Celia's somatic (skin) cells into embryos, a delicate biological black-arts process. To do it, they needed a substantial collection of viable goat egg cells. They obtained
them by placing thirty domestic goats into a state of superovulation, using hormones to stimulate the ovaries to produce mature egg cells.

Working under a microscope and using micromanipulators, the experimenters removed the nucleus from each egg cell and replaced it with one of Celia's somatic cells. Next came the step that transformed the two cellular parts into a single working entity: the researchers applied two short pulses of electrical current to each cell, a process known as electrofusion. They then incubated the resulting fused cells, creating fifty-four reconstructed embryos. These were now essentially Celia's egg cells, as crafted through biotechnology.

Finally, according to Folch, “we transferred the cloned bucardo embryos to thirteen female recipients [who were either Spanish ibex goats or mixed hybrids], having two pregnancies that terminated spontaneously before day 75 of pregnancy.”

All that toil and trouble resulted in no live births. So ended Experiment One.

In the winter of 2003, the researchers tried again with Experiment Two. This time they transferred 154 cloned embryonic bucardo cells into the wombs of 44 recipient goats. This yielded five pregnancies, one of which continued normally until term.

And then, according to the scientific publication describing the experiment, “at day 162 postfusion, we performed a caesarean section . . . One bucardo female weighing 2.6 kg [5.7 pounds] was obtained alive without external morphological abnormalities. The newborn displayed a normal cardiac rhythm as well as other vital signs at delivery (i.e., open eyes, mouth opening, legs and tongue movements) . . . To our knowledge, this is the first animal born from an extinct subspecies.”

It was Wednesday, July 30, 2003, a turning point in the history of biology. For on that date, all at once, extinction was no longer forever.