UTMB lab assessments Pfizer COVID vaccine: gunshots
University of Texas Medical Branch researchers help test Pfizer-BioNTech COVID-19 vaccine against coronavirus variants. Joao Paulo Burini / Getty Images Hide caption
Joao Paulo Burini / Getty Images
Joao Paulo Burini / Getty Images
The government says people who were vaccinated against COVID-19 eight months ago will need a booster vaccination.
This decision is based in part on blood tests that show that antibody levels in people who have been vaccinated decrease over time.
Some of these tests were done at the University of Texas Medical Department at Galveston, Texas.
Partly because of the special facility, partly because of a test developed there, and partly because of a personal relationship between an executive at Pfizer and a professor at the university.
The UTMB campus is a mix of old and new buildings near the north end of Galveston Island.
The virologist Pei-Yong Shi moved from Singapore six years ago to where he worked for the pharmaceutical company Novartis. He was attracted to Galveston because it has what is known as a BSL-3 Biosafety Level 3 facility – a specialized laboratory that allows researchers to safely work on dangerous viruses.
Shi had worked with the Zika virus earlier last year. But when the coronavirus showed up, he asked the Centers for Disease Control and Prevention to send him a sample so he could work on this virus. It didn’t take long for the CDC to stick to it.
Shi remembers a call from a colleague.
“He told me, ‘The virus is there.’ And that’s the day we started work: 5 am, February 11th, ”says Shi.
Glowing virus speeds up test
Shi planned to do a neutralization test, a blood test that would show if a particular drug or vaccine could prevent the virus from infecting cells in the lab. A successful test wouldn’t be a guarantee, but rather a good indication that the same drug or vaccine would prevent the virus from infecting people or making people sick.
To perform the assay, take cells grown in the laboratory (these are cells that originally came from monkey kidneys) and mix them with the coronavirus. Then serum from vaccinated people is added. If the serum contains antibodies to the virus, it prevents the virus from infecting the cells. If this is not the case, the virus infects the cells.
One of Shi’s tricks was to speed up this test by adding a fluorescent marker to the virus. If the cells were infected, they would glow.
Shi started working on his assay as soon as the virus arrived. “We developed the system just 42 days later,” he says. “And then I remember March 26th is my first contact with Pfizer.”
Pfizer had developed a novel vaccine with German biotech company BioNTech, and to test it they urgently needed an assay like the one Shi’s laboratory had developed.
“The most important thing is that the [assay] requires BSL-3 containment, “says Phil Dormitzer, Pfizer’s chief scientific officer, viral vaccines.” We didn’t have it then. “
But Shi did.
And there was another factor in favor of cooperation. Prior to joining Pfizer, Dormitzer worked at Novartis, where he had worked with Shi on occasion.
When Dormitzer found out that Shi had the right assay and facilities and could do the job, he was delighted.
“It’s very good to work with someone you know and trust,” says Dormitzer.
Pfizer team arrives by helicopter
Pfizer was excited about Shi’s development. The company wanted to test the vaccine on 40,000 people around the world, and Pfizer scientists wanted to make sure its assay was reliable.
The collaboration began in spring 2020 when commercial travel was difficult. Shi recalls that an entire Pfizer crew arrived by helicopter.
“They have their compliance people,” he says. “They have their test subjects. They have their virology.
The blood samples that Pfizer Shi sends are kept in a room in the hallway next to his office.
When you are ready to assay the samples, take them to the BSL-3 facility in a neighboring building.
You have to go through two airtight doors to reach the vestibule of the BSL-3 system.
The room is under negative pressure, ie air flows in, not out into the hallway.
The vestibule is for people entering the BSL-3 laboratory. No visitor allowed. The room has racks for protective equipment: face shields, gowns, gloves and special air-purifying breathing apparatus.
The assay is performed at the facility as a precautionary measure to ensure worker safety and prevent the virus from entering the world.
Encouraging results support clinical testing
In the spring of last year, Pfizer began blood testing of the first volunteers to receive the company’s experimental vaccine. In July, Pfizer was so encouraged by the results that it conducted clinical trials to show that the vaccine was safe and effective. By December, the Food and Drug Administration approved Pfizer’s emergency vaccine and the company was ready to ship it.
Several companies were working on COVID-19 vaccines with Pfizer at the same time, and some of them also contacted Shi. But he says he decided to work with Pfizer.
“If we want to make a difference, we cannot expand to help 10 companies. If that’s the case, in the end you won’t help anyone, ”says Shi.
Shi continues to work with Pfizer, testing blood samples to see if they have antibodies that work against the new virus variants.
He also tested blood samples from people taken months after vaccination to see if their antibody levels were going down over time.
Shi has data that shows they are in decline. This is part of the evidence that convinced federal health officials to announce this week that a booster vaccination is needed.
Shi says it would have been easier to make a decision about boosters if there was a precise limit, a specific antibody level too low to be protective.
“But that cutoff limit has not yet been defined in the field. So it’s everyone’s guess,” says Shi.
However, the government is counting on Shi’s results to tell us something important.