She a.s.sured them it wasn"t an issue right then. In fact, Hensley did have a date lined up that night, a first date with a man she didn"t know very well. Finally, she phoned him and asked if he wouldn"t mind putting off the date, since she had just had a potential exposure to Ebola virus. He was very understanding.
She drove back to her apartment, which seemed freezing cold, and so she placed a s.p.a.ce heater on the floor by her grandmother"s couch, turned it on, lay down on the couch, and wrapped herself in a blanket. Her cat, Addy, curled up with her. Then she began calling her closest friends, and she stayed up late that night on the couch talking with them. She slept for a while, and awoke from a turmoil of blue-suit nightmares. She was boiling hot, her throat was parched, she had a fever.... Where am I? and there was Addy, purring at her side.
Hensley continued her work with Ebola virus, somewhat oblivious to the heated arguments between smallpox experts about whether variola should live or die. The smallpox virus was a relic of the past to her, a virus with a seventies feel, like an alb.u.m by Debbie Boone. She more interested in trans-species jumps of viruses that were emerging right now.
She also had her mind on children: what was a woman scientist on a fast track supposed to do about children? She started playing volleyball in a league and met a man named Rob Tealle, who became her significant other. He was a builder and general contractor who worked around Frederick-a smart man, but not a scientist. Hensley packed her grandmother"s couch into a U-Haul trailer and moved to an apartment in Frederick. She and Tealle became very close. It was the biggest relief in the world to go home after a day in a blue suit and talk about normal things with a normal guy.
A Failure in Atlanta SPRING 2000.
After the WHO committee opened a three-year window in which live smallpox could be worked on, Peter Jahrling and John Huggins put together a plan to try to infect monkeys with the virus. The Food and Drug Administration has long insisted that new drugs for a human disease be tested in humans before they are licensed for use. This is not possible in the case of smallpox. Since smallpox has been eradicated, no one is infected with it, and you can"t (legally) infect people with a lethal disease just to study them. So the FDA was in a bind over smallpox. It published a draft of a new rule, the Animal Efficacy Rule, which says that for an exotic threat such as smallpox, the FDA would license a new drug or vaccine if it could be tested in two different animals that had the disease, and if the disease resembled the human disease-if there was an animal model of the disease.
Peter Jahrling wanted to get an animal model of smallpox that they could test drugs on and that the FDA would accept. Since there is no smallpox at USAMRIID, Jahrling a.s.sembled a research team and flew them to Atlanta. He got permission from CDC officials to bring the smallpox freezer out from its hiding place and allow his team to take out the smallpox, warm it up, and try to infect monkeys with it.
Jahrling decided to infect the monkeys by having them breathe smallpox in the air, to mimic the way it spreads among humans.
The USAMRIID scientists built a portable aerosol chamber that they called the Monkey Cabinet. It is a huge device made of plastic and steel, and it has wheels, so it rolls. They trucked the Monkey Cabinet and a number of monkeys down to Atlanta and installed them in the CDC"s Maximum Containment Lab. Jahrling and Huggins exposed monkeys to around two million human infectious doses of smallpox. Then Jahrling went back to Fort Detrick to attend to other business, while John Huggins remained in Atlanta, monitoring the monkeys. A few days after they"d breathed enough smallpox to take out a city, some of the monkeys got a flush across their chests, and a couple of them developed a few pimples. After a day or so, the monkeys recovered.
As the experiment was winding down, Jahrling began to feel desperate. He was afraid that D. A.
Henderson would label this experiment a failure and would say "I told you so" and that it confirmed the widely held belief that animals could never be successfully infected with human smallpox. The clock was ticking. A year had pa.s.sed since the WHO had extended the deadline for destroying the smallpox virus, and Jahrling needed data that looked at least vaguely promising, or the WHO might not allow him to do another experiment. He needed someone to fly down to Atlanta, take some blood from the monkeys, and do a quick study of it right there. Maybe that would show something. He asked Joan Geisbert, but her son was graduating from high school in Frederick, and she was going to be there no matter what.
Lisa Hensley could probably run the tests, but she was wrapped up in Ebola research and pretty clearly did not want to be involved with smallpox. He asked her anyway.
"Yeah, I"ll do it, sir," she said.
Jahrling began to wonder about this. If Hensley went down to Atlanta and started working with smallpox, what would happen if she enjoyed it? What if people at the CDC were impressed with her?
He told Tom Geisbert, confidentially, that he was afraid the CDC people might try to poach her.
USAMRIID and the CDC had a history of strained relations. Jahrling told Hensley that he would accompany her to Atlanta.
She was annoyed, and when she was annoyed she tended to rely on Tom Geisbert for advice.
She dropped by his office and asked, "Does he think I need a baby-sitter in Atlanta?" Geisbert explained Jahrling"s worry about CDC poaching.
Jahrling and Hensley flew to Atlanta at the beginning of May 2000. They sat next to each other on the government-budget AirTran flight, and Hensley was uncomfortable, not to say tongue-tied. At the CDC, they put on blue suits and entered the Maximum Containment Lab.
Hensley worked all day taking blood samples from monkeys that had breathed ten million human doses of smallpox and seemed fine.
Three days later, Hensley was back at Fort Detrick with the raw data from her tests. A month later, Jahrling flew to Geneva and presented Hensley"s data to the Ad Hoc Committee on Orthopoxvirus.
He argued that the data was "suggestive," which meant that the experiment had bombed. D. A.
Henderson argued that Jahrling would never be able to infect monkeys with smallpox, that it just wasn"t going to work. Jahrling pleaded for another chance, and the committee agreed to let him try again-in another year.
Then, out of nowhere, came a discovery that shook the smallpox experts to their cores.
Nuclear Pox September 2-3, 2000 A few months after the failure of his monkey-model experiment, on a hot Sat.u.r.day in early September 2000, Peter Jahrling flew to Montpellier, France, for the thirteenth International Poxvirus Symposium. It was held at Le Corum, a modern conference center in the middle of town. The place was jammed with more than six hundred poxvirus experts from around the world, many of them milling in the lobbies and chain-smoking cigarettes. On Sunday afternoon, Jahrling wandered around a lobby where scientists were showing poster papers. A poster paper is much like the reports that children give in school. It"s usually about an experiment that doesn"t warrant a full presentation. A scientist makes up a poster that summarizes the experiment, hangs it up and stands next to it, and answers questions.
There were fifty or sixty poster papers hanging on bulletin boards. Jahrling b.u.mped into Richard Moyer, an American poxvirus expert who is the chairman of the Department of Molecular Genetics at the University of Florida in Gainesville. There was a lot of noise and cigarette smoke, and they wanted to talk, so they found a poster that n.o.body was looking at. Jahrling and Moyer placed themselves to one side, so they wouldn"t disturb the scientist standing next to the poster, and they chatted about some of the things they"d been learning. Moyer glanced over at the poster. He stopped talking.
The experiment described on the poster had been carried out by a group of Australian government researchers from the Co-operative Research Centre for the Biological Control of Pest Animals, in Canberra. They were using viruses to try to cut down populations of mice. The scientist who led the work, Ronald J. Jackson, was the man standing beside the poster. Jackson is tall, with a roundish face, dark, short hair, and a nut-brown tan. He was a pleasant-looking man, wearing a yellow short-sleeved shirt and brown pants.
The Australian group had been working with the mousepox virus, which is closely related to smallpox. Mousepox, which is also called ectromelia, cannot infect humans and doesn"t make them sick, but it is lethal in some types of mice. The Australian group had been infecting mice with an engineered mousepox virus that was supposed to make the mice sterile. But the engineered mousepox had wiped out the mice.
The mice were naturally resistant to mousepox, and some of them had also been vaccinated.
Even so, the engineered virus had sacked them. It had wiped out a hundred percent of the naturally resistant mice and sixty percent of the immunized mice.
The Australian scientists had added a single foreign gene, the mouse IL-4 gene, to natural mousepox virus. The mouse IL-4 gene produces a protein called interleukin-4, a cytokine that acts as a signal in the immune system. By putting a mouse gene into natural mousepox, the researchers had created a superlethal, vaccine-resistant pox of mice.
If a pox that crashes through a vaccine could be made for mice, then one could probably be made for men.
"My G.o.d, Peter, can you believe what these jacka.s.ses have done?" Moyer blurted.
Jahrling stared at the poster. He got the point of it right away: the Australians had engineered a poxvirus that could overwhelm the vaccine, and they"d done it by putting a single gene from the mouse into the virus. One mouse gene into the pox. Child"s play. "Holy s.h.i.t," he said.
"This virus just mowed down these immunized animals," Moyer whispered in a low voice to Jahrling, staring at the mouse man from Australia, who was looking rather hopefully at them, like a salesman without any customers. But the two Americans drifted away. "If I were a bioterrorist, Peter, I would rip that paper down and take it home with me." Moyer glanced back at the Australian. "Maybe that paper should come down right now. It makes me wonder if the vaccination strategy for smallpox would work," Moyer said.
Jahrling went back to his hotel room and mentally kicked trash cans around. The poster looked to him like a blueprint for the biological equivalent of a nuclear bomb. People were attending the conference from countries that were suspected of secretly developing smallpox as a weapon, and there was no doubt that genetic engineering was something they were perfectly capable of doing. This poster might give them ideas for how to make a smallpox that could be vaccine-proof. He was especially worried about the Vector scientists. Lev Sandakhchiev was walking around, adding his blue Russian cigarette smoke to the haze in the conference center.
It was late in the afternoon, and there was a bus trip planned to the Pont du Gard, a Roman aqueduct that spans a gorge near Nimes. Jahrling went downstairs and found d.i.c.k Moyer. They got on the bus together and sat down. Then Moyer spotted Ron Jackson sitting by himself near the back of the bus. "See you later," Moyer said, and he hurried down the aisle and claimed the seat next to Jackson.
"That paper of yours is one of the best papers at the meeting," he said, trying to break the ice.
The bus wound through the beautiful terrain of Languedoc, through olive groves and past limestone cliffs. Moyer found Jackson to be a "nice guy, kind of a shy guy, and a good scientist." They had a talk about how, exactly, the engineered pox had wiped out the immune mice. Moyer was very interested in the exact way in which a poxvirus could trigger a storm in the immune system and overwhelm the vaccine. "Ron Jackson and his group knew what they had done," he said later.
"Anybody working in this field would have to be absolutely r.e.t.a.r.ded not to see the implications of it with the vaccine for smallpox. They"re professionals, and they saw it. They agonized over publishing their experiment. But I still can"t believe they published it." A vaccineresistant smallpox would be everyone"s worst nightmare come true. We could be left trying to fight a genetically engineered virus with a vaccine that had been invented in 1796.
The Australian researchers were working for the government, and they had asked officials what they should do. Information travels fast via the Internet. Word could leak out about their experiment, even if they didn"t publish it. Putting the IL-4 gene into a poxvirus was such simple work that a grad student or summer intern could probably do it. Virus engineering had become standardized, and there were kits you could order in the mail for doing it. It was getting easier to alter the genes of a virus all the time, and poxviruses were just about the easiest viruses to engineer in the laboratory.
Ron Jackson and his colleagues-princ.i.p.ally, a molecular biologist named Ian Ramshaw, who had done the technical work of constructing the virus-talked it over with one of the leading eradicators of smallpox, the Australian pox virologist Frank Fenner. Fenner had done some of the early and important research on mousepox virus, and he is the princ.i.p.al author of the Big Red Book-Smallpox and Its Eradication. He advised them to publish. He felt that there were reasons to think that IL-4 smallpox-smallpox with the human IL-4 gene spliced into it-might not work the same way as IL-4 mousepox did in mice. Furthermore, he felt that an engineered smallpox that did spread through vaccinated humans would not be useful as a biological weapon because it would kill too many people too fast, and so would not spread well, in his opinion, and it might kill the people who made it. Fenner also believed that a terror group or a nation would need to test the engineered smallpox on human subjects in order to be sure it worked. That was a difficult hurdle, he reasoned.
As for Jackson and Ramshaw, one impulse for publishing their work seems to have been simply to remind the world that the genetic engineering of virus weapons was something quite possible. They wanted to warn the community of biologists to stop pretending the problem didn"t exist, and to start discussing it and dealing with it.
The Jackson-Ramshaw paper was published, with a small burst of publicity and media attention, in the Journal of Virology in February 2001. At that point, the technique for engineering a presumably vaccine-resistant super mousepox became available worldwide on the Internet.
The Jackson-Ramshaw experiment provoked an uneasy reaction in the American intelligence community. CIA biologists were apparently aware of the paper, since it pointed to a vulnerability in the government"s plans to a.s.semble a stockpile of vaccine. The paper was discussed at the National Security Council. One member of the NSC believed that the Australian scientists had intentionally published their experiment out of scientific pride. This was an unreasonably cynical of Australian scientists, but it reflected the unease with which the intelligence community viewed the possibilities for genetic engineering of virus weapons.
After giving a couple of interviews with journalists, Jackson and his group decided to let others do the talking for them. Dr. Annabelle Duncan, an Australian government scientist, argued that the researchers had done nothing wrong and that unexpected findings are a normal part of science. "I got especially rabid e-mail from people in the United States," she said. "But it would have been silly and dangerous not to publish the paper, because there would have been an implication that we were doing something harmful." She maintained that the group had been surprised by the result and had never thought the immunized mice would die, and this seems true. In essence, the Jackson-Ramshaw team had had a laboratory accident with an engineered virus and had chosen to tell the world what had happened.
A month later, officials at the CDC gave the U.S. Army permission to try a second experiment to see if, somehow, they could create a monkey model of smallpox. Peter Jahrling put Lisa Hensley in charge the experiment.
A Slight Argument MAY 29, 2001.
At eight o"clock in the evening, Peter Jahrling was in his living room, packing a battered suitcase.
The sun had set, but the birds were still singing, and the sky glowed with spring. Jahrling had to catch a flight to Atlanta. The Jahrlings" master bedroom is small, and his wife, Daria, had told her husband that she did not want him packing there. "That suitcase of yours has been G.o.d knows where, like Siberia.
You drag it down streets where dogs walk," she said. "I don"t want that thing on our bed."
So he was packing the suitcase on the rug in front of the television set, which was on, although n.o.body was watching it. Daria was gathering the children"s laundry from their rooms, walking briskly around the house with a plastic laundry basket. Their five-year-old daughter, Kira, was rolling on the couch in a bunny suit, drawing on a piece of paper with a crayon.
Daria paused briefly, holding the laundry basket. "Peter, how long are you going to be gone this time?" She is a casual person with an honest way about her. She teaches English at a local high school: Shakespeare and T. S. Eliot and the Imagist poets.
"It depends on how it goes," he answered. He added a T-shirt and shorts.
"I thought you didn"t go into the s.p.a.ce-suit lab anymore. Don"t you have people who can do the work for you?"
He added a light blue polyester sport coat to the suitcase. "Frankly, I"m the only one who has the pa.s.sion to make it all come together right."
Daria carried the laundry downstairs and started the washing machine. Peter was immune to everything-he had been vaccinated for anthrax and smallpox-but she and the kids weren"t. She had told her sister that she wished they all had some of Peter"s blood in them. She went back upstairs.
Kira hopped off the couch and ran over to her father, holding her paper. "Daddy, I need a clipboard."
He went into his office and got a clipboard. She hung a picture on it and showed it to him.
"Hey, that"s nice, Kira."
"Go brush your teeth, baby," Daria said to Kira. Kira buzzed off to the bathroom.
"I"m going to miss her."
"You never see her. You usually don"t get back from work until she"s in bed."
"All I can say is, there are reasons for coming up with countermeasures to smallpox. We all know that crazies exist."
A lot of their communication was nonverbal. She gave him a smile that was a mixture of impatience, annoyance, and wry amus.e.m.e.nt, a look they knew meant, You live in Peter"s world. He tucked Kira in bed and read her a story and arrived in Atlanta at midnight.
Chaos in Level 4 MAY 30, 2001 (DAY MINUS-ONE).
The monkey-model team stayed at a hotel in the suburbs, not far from the CDC. At sunrise they were drinking coffee and eating bagels, scrambled eggs, and fruit in the hotel"s cafe. The monkey-model team consisted of Peter Jahrling, John Huggins, Lisa Hensley, and an Army veterinary pathologist, Lieutenant Colonel Mark Martinez. There was also an animal caretaker named James Stockman and two veterinary technicians, Joshua Shamblin and Sergeant Rafael Herrera. A separate science team, headed by a biologist named Louise Pitt, ran the Monkey Cabinet. This was big biology-expensive and complex. Everyone in the room was keyed up.
Lisa Hensley wasn"t a morning person and never ate breakfast. She bought a Diet c.o.ke and drove with Sergeant Herrera to the CDC in a rented car. It was a cool, pleasant morning, and the sun was flashing through c.h.i.n.kapin trees and loblolly pines, and the air held scents of Georgia summer. They drove down a hollow and up a hill, turned in to the CDC campus, and showed their identification badges to a security guard. The badges were marked "Guest Researcher."
They walked through a security door and crossed an open area, went through another security checkpoint, and arrived inside the Maximum Containment Lab. The MCL is a six-story building but does not seem large; it is embedded in the side of a hill, and three of its stories are partly belowground.
It is attached to a larger structure known as Building 15. The MCL has a line of purplish smoked-gla.s.s windows that make the building look like an aquarium. There were television cameras and armed guards around. The variola freezer had been removed from its normal hiding place or places, and the security people had a live camera watching the freezer inside the hot zone.
CDC officials had decided that the Army people could work in a corrridor of the sub-subbas.e.m.e.nt. The Army people felt they were getting a bit of a hazing, for it was clear that not everyone at the CDC was happy to have them there, working with smallpox. As an inst.i.tution, CDC was proud of the leading role it had played in the Eradication and there were undercurrents of feeling around the CDC that it was just not right to be warming up variola and doing experiments with it.
The Army"s work area consisted of three small desks lined up in the corridor, illuminated by bas.e.m.e.nt windows that looked out on the wheels of parked cars. Hensley sat down at a desk, pulled the Diet c.o.ke from her bag, popped it open, and sipped it. The others arrived, but there weren"t enough desks, so they stood, drinking coffee from foam cups. The animal caretakers were going to go in first, to feed the monkeys. Hensley waited for a while and then went up three flights of stairs and through another security point to an entry door that led inward to the smallpox. The MCL was divided into two separate hot zones, east and west. She pushed through a small door into MCL West and into a small locker room, where she undressed. There was a circular scar on her upper left arm-the site of a fresh smallpox immunization. She pulled a green cotton surgical jumpsuit from a shelf and b.u.t.toned up the front. The fabric was faded and tore easily: it had been sterilized in an autoclave many times. Another shelf held athletic socks that had been sterilized and were crispy and brownish. She rummaged around for a pair that seemed less crispy. Barefoot a.nd holding the socks, she walked through a wet shower stall and opened a door. It led to a supply closet. She walked through the closet, pushed open a door, and entered the s.p.a.ce-suit room.
It was a Level 3 room, close to the hot side, jammed with blue s.p.a.ce suits hanging on hooks.
Each suit was marked with the name of its owner. Most of the suits belonged to CDC scientists. They had seen hard use-the seats of some of them were patched with black tape. (They tend to develop holes in the b.u.t.tock area when you sit down.) Her s.p.a.ce suit was brand-new. She really liked that new-s.p.a.ce-suit smell. She snapped on surgical gloves, taped the wrists to the sleeves of her scrubs, and carried her suit back into the supply closet, where she sat on a box and put her legs into the suit. She stood up, pulled the faceplate down over her head, and closed the front seal, which snapped shut automatically. She selected an air regulator-a steel canister with a shoulder strap. She slung it over her shoulder and plugged the regulator into her suit.
There was a stainless-steel door on the inward side of the room that had the red biohazard symbol on it. She shuffled into the air-lock decon shower, closed the outer door, opened the inner door, and stepped through to the hot side. She was in a small room where galoshes were sitting on the floor-the boot room. She stepped into a pair that looked about her size. The galoshes were to protect the feet of her suit from developing holes. Then she pushed through a swinging door into the main room of MCL West.
The main room was forty feet long, and it was in the shape of an L. The walls were covered with brilliant white tiles, and the light was bright. Red air hoses dangled in coils from the ceiling. An array of freezers stood along one wall, one of which was the smallpox freezer. Hensley started moving through the room. You didn"t exactly walk in Level 4, you shuffled. She pushed through a door into a lab room.
This would be her workplace for the duration of the experiment. She stood up on tiptoes, pulled down an air hose, and plugged it into her regulator. There was a roar, her suit pressurized, and dry, cool air washed past her face. She spent the morning setting up test kits, getting ready for the awakening of variola.
On the far end of the main room there was a heavy steel door, and beyond it was the animal room, which was now crowded with people in s.p.a.ce suits. The room contained four banks of monkey cages. The monkeys were calm, not vocalizing much, since they had been living in Level 4 for weeks, and they had grown used to being around humans wearing s.p.a.ce suits. Each bank of cages had a plastic tent over it, to keep smallpox from spreading from one bank to another, in case any monkeys did develop smallpox. There were eight monkeys in the cages. The monkeys were crab-eating macaques from Southeast Asia. They had grayish-brown fur, pointed ears, and sharp, canine fangs. Jim Stockman, the animal caretaker, had fed them a breakfast of monkey biscuits. They had eaten some of their biscuits and had thrown others around the room. Stockman had cleaned up the mess. All the cages had bra.s.s padlocks on them-a crab-eating monkey can figure out any latch.
Mark Martinez, the veterinary pathologist, was in the monkey room, too, getting things set up.
Martinez is a soft-spoken man in his forties, with brown eyes and wire-rimmed gla.s.ses. Some years earlier, he had attended Airborne school at Fort Benning, Georgia. One day, he had been walking around the base and had found a graveyard for dogs, overgrown with weeds. Among them were bra.s.s plates and slabs of stone. Each marker displayed the name of a dog, with its dates of birth and death.
They had been killed in action during the Vietnam War, had been shipped home, buried, and forgotten.
Martinez thought about how many of the dogs had died in combat, perhaps defending their human companions, and he had the graveyard mowed and tidied up, and he cleaned the grave markers. He felt that the dogs had died for their country.
Lisa Hensley was standing at a work counter, setting up her equipment. She was looking down at her hands, when she noticed that her right outer glove had developed a crack in the wrist. The glove was rotten.
-She had no tolerance for bad gloves. Time to get out.
She picked up a bottle of Lysol, sprayed her glove, and headed for the exit. She took off her galoshes and stepped into the decon shower and pulled a handle to start the cycle.
A spray of water, then Lysol came down over her. After it ran for seven minutes, she turned a handle to shut it off. It wouldn"t turn off. It was jammed open, and the shower was still running with Lysol.
"Oh, c.r.a.p," she said. She returned to the hot side and tapped the vet tech, Josh Shamblin, on the shoulder and pointed to the air lock. "It"s running. It won"t stop." She had to shout, since both of them were wearing earplugs inside noisy suits; it helped if you could read lips.
He said to her, "Get Jim."
Jim Stockman had worked in MCL West before, and he knew how to fix the decon shower. He clambered into the air lock and started banging around in the spray, trying to fix the mechanism.
Peter Jahrling had arrived in the gray area with John Huggins, and they were peering at Stockman through a window in the air lock. "What the heck are you doing?" Jahrling mouthed.
"Fixing it."
Suddenly, the floor drains in the main room began puking up nasty yellow foam. It was dirty Lysol, overflowing from the waste drains.
Rafael Herrera came running out of his workroom, lumbering in his suit, shouting, "We"ve got a flood in here!"
Hensley went over to the window of the shower and started pounding on the gla.s.s. "Jim! Jim!
Look!" Mark Martinez and the others were now careening around the main room, their voices sounding dull and faint as they yelled at one another inside their suits. One of them picked up the receiver of a wall phone and called the CDC"s Level 4 janitorial services: "We"ve got a Lysol flood in here! The plumbing is backing up!"
The monkeys probably thought it was pretty exciting.
The shower stopped. Stockman opened the door of the air lock, and more Lysol poured into the room. They found a Sears shop vacuum and ran it around the hot zone to suck up the flood.
It had been a long day. The team drove back to the hotel, and most of them went straight to bed. Hensley stayed up long enough to phone Rob Tealle. She told him that everything was okay, except for a flood in the lab. He had been working on a project to build some houses. The project was winding down, and he was planning to direct his business toward furniture building. It was a brief conversation.
The Awakening May 31, 2001 (Day Zero) AT EIGHT O"CLOCK the next morning, John Huggins crossed through the main room of MCL West in a blue suit, went somewhere, and retrieved the Smallpox Key. Huggins is a calm, deliberate, chunky man with a pointed nose, tortoisesh.e.l.l eyegla.s.ses, and dark, wavy hair with a splash of gray at the temples. He went to an array of freezers of various kinds, all lined up against a wall. There were chest freezers, and there were freezers that looked like kitchen refrigerators, and there were several cylindrical tanks made of stainless steel, sitting on wheels, which were liquid-nitrogen freezers. The freezers all had digital displays showing the temperature and status of the freezer.
The liquid-nitrogen freezers were shiny and new and looked a little like nuclear-reactor vessels.