Harvard Researchers Are Using a Breakthrough Tool to Find the Antibodies That Best Knock Out the Coronavirus
Lina Zeldovich has written about science, medicine and technology for Popular Science, Smithsonian, National Geographic, Scientific American, Reader’s Digest, the New York Times and other major national and international publications. A Columbia J-School alumna, she has won several awards for her stories, including the ASJA Crisis Coverage Award for Covid reporting, and has been a contributing editor at Nautilus Magazine. In 2021, Zeldovich released her first book, The Other Dark Matter, published by the University of Chicago Press, about the science and business of turning waste into wealth and health. You can find her on http://linazeldovich.com/ and @linazeldovich.
To find a cure for a deadly infectious disease in the 1995 medical thriller Outbreak, scientists extract the virus's antibodies from its original host—an African monkey.
"When a person is infected, the immune system makes antibodies kind of blindly."
The antibodies prevent the monkeys from getting sick, so doctors use these antibodies to make the therapeutic serum for humans. With SARS-CoV-2, the original hosts might be bats or pangolins, but scientists don't have access to either, so they are turning to the humans who beat the virus.
Patients who recovered from COVID-19 are valuable reservoirs of viral antibodies and may help scientists develop efficient therapeutics, says Stephen J. Elledge, professor of genetics and medicine at Harvard Medical School in Boston. Studying the structure of the antibodies floating in their blood can help understand what their immune systems did right to kill the pathogen.
When viruses invade the body, the immune system builds antibodies against them. The antibodies work like Velcro strips—they use special spots on their surface called paratopes to cling to the specific spots on the viral shell called epitopes. Once the antibodies circulating in the blood find their "match," they cling on to the virus and deactivate it.
But that process is far from simple. The epitopes and paratopes are built of various peptides that have complex shapes, are folded in specific ways, and may carry an electrical charge that repels certain molecules. Only when all of these parameters match, an antibody can get close enough to a viral particle—and shut it out.
So the immune system forges many different antibodies with varied parameters in hopes that some will work. "When a person is infected, the immune system makes antibodies kind of blindly," Elledge says. "It's doing a shotgun approach. It's not sure which ones will work, but it knows once it's made a good one that works."
Elledge and his team want to take the guessing out of the process. They are using their home-built tool VirScan to comb through the blood samples of the recovered COVID-19 patients to see what parameters the efficient antibodies should have. First developed in 2015, the VirScan has a library of epitopes found on the shells of viruses known to afflict humans, akin to a database of criminals' mug shots maintained by the police.
Originally, VirScan was meant to reveal which pathogens a person overcame throughout a lifetime, and could identify over 1,000 different strains of viruses and bacteria. When the team ran blood samples against the VirScan's library, the tool would pick out all the "usual suspects." And unlike traditional blood tests called ELISA, which can only detect one pathogen at a time, VirScan can detect all of them at once. Now, the team has updated VirScan with the SARS-CoV-2 "mug shot" and is beginning to test which antibodies from the recovered patients' blood will bind to them.
Knowing which antibodies bind best can also help fine-tune vaccines.
Obtaining blood samples was a challenge that caused some delays. "So far most of the recovered patients have been in China and those samples are hard to get," Elledge says. It also takes a person five to 10 days to develop antibodies, so the blood must be drawn at the right time during the illness. If a person is asymptomatic, it's hard to pinpoint the right moment. "We just got a couple of blood samples so we are testing now," he said. The team hopes to get some results very soon.
Elucidating the structure of efficient antibodies can help create therapeutics for COVID-19. "VirScan is a powerful technology to study antibody responses," says Harvard Medical School professor Dan Barouch, who also directs the Center for Virology and Vaccine Research. "A detailed understanding of the antibody responses to COVID-19 will help guide the design of next-generation vaccines and therapeutics."
For example, scientists can synthesize antibodies to specs and give them to patients as medicine. Once vaccines are designed, medics can use VirScan to see if those vaccinated again COVID-19 generate the necessary antibodies.
Knowing which antibodies bind best can also help fine-tune vaccines. Sometimes, viruses cause the immune system to generate antibodies that don't deactivate it. "We think the virus is trying to confuse the immune system; it is its business plan," Elledge says—so those unhelpful antibodies shouldn't be included in vaccines.
More importantly, VirScan can also tell which people have developed immunity to SARS-CoV-2 and can return to their workplaces and businesses, which is crucial to restoring the economy. Knowing one's immunity status is especially important for doctors working on the frontlines, Elledge notes. "The resistant ones can intubate the sick."
Lina Zeldovich has written about science, medicine and technology for Popular Science, Smithsonian, National Geographic, Scientific American, Reader’s Digest, the New York Times and other major national and international publications. A Columbia J-School alumna, she has won several awards for her stories, including the ASJA Crisis Coverage Award for Covid reporting, and has been a contributing editor at Nautilus Magazine. In 2021, Zeldovich released her first book, The Other Dark Matter, published by the University of Chicago Press, about the science and business of turning waste into wealth and health. You can find her on http://linazeldovich.com/ and @linazeldovich.
Stronger psychedelics that rewire the brain, with Doug Drysdale
A promising development in science in recent years has been the use technology to optimize something natural. One-upping nature's wisdom isn't easy. In many cases, we haven't - and maybe we can't - figure it out. But today's episode features a fascinating example: using tech to optimize psychedelic mushrooms.
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These mushrooms have been used for religious, spiritual and medicinal purposes for thousands of years, but only in the past several decades have scientists brought psychedelics into the lab to enhance them and maximize their therapeutic value.
Today’s podcast guest, Doug Drysdale, is doing important work to lead this effort. Drysdale is the CEO of a company called Cybin that has figured out how to make psilocybin more potent, so it can be administered in smaller doses without side effects.
The natural form of psilocybin has been studied increasingly in the realm of mental health. Taking doses of these mushrooms appears to help people with anxiety and depression by spurring the development of connections in the brain, an example of neuroplasticity. The process basically shifts the adult brain from being fairly rigid like dried clay into a malleable substance like warm wax - the state of change that's constantly underway in the developing brains of children.
Neuroplasticity in adults seems to unlock some of our default ways of of thinking, the habitual thought patterns that’ve been associated with various mental health problems. Some promising research suggests that psilocybin causes a reset of sorts. It makes way for new, healthier thought patterns.
So what is Drysdale’s secret weapon to bring even more therapeutic value to psilocybin? It’s a process called deuteration. It focuses on the hydrogen atoms in psilocybin. These atoms are very light and don’t stick very well to carbon, which is another atom in psilocybin. As a result, our bodies can easily breaks down the bonds between the hydrogen and carbon atoms. For many people, that means psilocybin gets cleared from the body too quickly, before it can have a therapeutic benefit.
In deuteration, scientists do something simple but ingenious: they replace the hydrogen atoms with a molecule called deuterium. It’s twice as heavy as hydrogen and forms tighter bonds with the carbon. Because these pairs are so rock-steady, they slow down the rate at which psilocybin is metabolized, so it has more sustained effects on our brains.
Cybin isn’t Drysdale’s first go around at this - far from it. He has over 30 years of experience in the healthcare sector. During this time he’s raised around $4 billion of both public and private capital, and has been named Ernst and Young Entrepreneur of the Year. Before Cybin, he was the founding CEO of a pharmaceutical company called Alvogen, leading it from inception to around $500 million in revenues, across 35 countries. Drysdale has also been the head of mergers and acquisitions at Actavis Group, leading 15 corporate acquisitions across three continents.
In this episode, Drysdale walks us through the promising research of his current company, Cybin, and the different therapies he’s developing for anxiety and depression based not just on psilocybin but another psychedelic compound found in plants called DMT. He explains how they seem to have such powerful effects on the brain, as well as the potential for psychedelics to eventually support other use cases, including helping us strive toward higher levels of well-being. He goes on to discuss his views on mindfulness and lifestyle factors - such as optimal nutrition - that could help bring out hte best in psychedelics.
Show links:
Doug Drysdale full bio
Doug Drysdale twitter
Cybin website
Cybin development pipeline
Cybin's promising phase 2 research on depression
Johns Hopkins psychedelics research and psilocybin research
Mets owner Steve Cohen invests in psychedelic therapies
Doug Drysdale, CEO of Cybin
How the body's immune resilience affects our health and lifespan
Story by Big Think
It is a mystery why humans manifest vast differences in lifespan, health, and susceptibility to infectious diseases. However, a team of international scientists has revealed that the capacity to resist or recover from infections and inflammation (a trait they call “immune resilience”) is one of the major contributors to these differences.
Immune resilience involves controlling inflammation and preserving or rapidly restoring immune activity at any age, explained Weijing He, a study co-author. He and his colleagues discovered that people with the highest level of immune resilience were more likely to live longer, resist infection and recurrence of skin cancer, and survive COVID and sepsis.
Measuring immune resilience
The researchers measured immune resilience in two ways. The first is based on the relative quantities of two types of immune cells, CD4+ T cells and CD8+ T cells. CD4+ T cells coordinate the immune system’s response to pathogens and are often used to measure immune health (with higher levels typically suggesting a stronger immune system). However, in 2021, the researchers found that a low level of CD8+ T cells (which are responsible for killing damaged or infected cells) is also an important indicator of immune health. In fact, patients with high levels of CD4+ T cells and low levels of CD8+ T cells during SARS-CoV-2 and HIV infection were the least likely to develop severe COVID and AIDS.
Individuals with optimal levels of immune resilience were more likely to live longer.
In the same 2021 study, the researchers identified a second measure of immune resilience that involves two gene expression signatures correlated with an infected person’s risk of death. One of the signatures was linked to a higher risk of death; it includes genes related to inflammation — an essential process for jumpstarting the immune system but one that can cause considerable damage if left unbridled. The other signature was linked to a greater chance of survival; it includes genes related to keeping inflammation in check. These genes help the immune system mount a balanced immune response during infection and taper down the response after the threat is gone. The researchers found that participants who expressed the optimal combination of genes lived longer.
Immune resilience and longevity
The researchers assessed levels of immune resilience in nearly 50,000 participants of different ages and with various types of challenges to their immune systems, including acute infections, chronic diseases, and cancers. Their evaluation demonstrated that individuals with optimal levels of immune resilience were more likely to live longer, resist HIV and influenza infections, resist recurrence of skin cancer after kidney transplant, survive COVID infection, and survive sepsis.
However, a person’s immune resilience fluctuates all the time. Study participants who had optimal immune resilience before common symptomatic viral infections like a cold or the flu experienced a shift in their gene expression to poor immune resilience within 48 hours of symptom onset. As these people recovered from their infection, many gradually returned to the more favorable gene expression levels they had before. However, nearly 30% who once had optimal immune resilience did not fully regain that survival-associated profile by the end of the cold and flu season, even though they had recovered from their illness.
Intriguingly, some people who are 90+ years old still have optimal immune resilience, suggesting that these individuals’ immune systems have an exceptional capacity to control inflammation and rapidly restore proper immune balance.
This could suggest that the recovery phase varies among people and diseases. For example, young female sex workers who had many clients and did not use condoms — and thus were repeatedly exposed to sexually transmitted pathogens — had very low immune resilience. However, most of the sex workers who began reducing their exposure to sexually transmitted pathogens by using condoms and decreasing their number of sex partners experienced an improvement in immune resilience over the next 10 years.
Immune resilience and aging
The researchers found that the proportion of people with optimal immune resilience tended to be highest among the young and lowest among the elderly. The researchers suggest that, as people age, they are exposed to increasingly more health conditions (acute infections, chronic diseases, cancers, etc.) which challenge their immune systems to undergo a “respond-and-recover” cycle. During the response phase, CD8+ T cells and inflammatory gene expression increase, and during the recovery phase, they go back down.
However, over a lifetime of repeated challenges, the immune system is slower to recover, altering a person’s immune resilience. Intriguingly, some people who are 90+ years old still have optimal immune resilience, suggesting that these individuals’ immune systems have an exceptional capacity to control inflammation and rapidly restore proper immune balance despite the many respond-and-recover cycles that their immune systems have faced.
Public health ramifications could be significant. Immune cell and gene expression profile assessments are relatively simple to conduct, and being able to determine a person’s immune resilience can help identify whether someone is at greater risk for developing diseases, how they will respond to treatment, and whether, as well as to what extent, they will recover.