New biomarker may lead to new clinical laboratory testing and treatments for long COVID
Researchers studying long COVID at the University Hospital of Zurich (UZH) and the Swiss Institute of Bioinformatics (SIB), both in Switzerland, have discovered a protein biomarker in blood that indicates a component of the body’s innate immune system—called the complement system—remains active in some individuals long after the infection has run its course. The scientists are hopeful that further studies may provide clinical laboratories with a definitive test for long COVID, and pharma companies with a path to develop therapeutic drugs to treat it.
Ever since the COVID-19 pandemic began, a subset of the population worldwide continues to experience lingering symptoms even after the acute phase of the illness has passed. Patients with long COVID experience symptoms for weeks, even months after the initial viral infection has subsided. And because these symptoms can resemble other illnesses, long COVID is difficult to diagnose.
This new biomarker may lead to new clinical laboratory diagnostic blood tests for long COVID, and to a greater understanding of why long COVID affects some patients and not others.
“Those long COVID patients used to be like you and me, totally integrated [into] society with a job, social life, and private life,” infectious disease specialist Michelè van Vugt, MD (above), Senior Fellow and Professor at Amsterdam Institute for Global Health and Development (AIGHD), told Medical News Today. “After their COVID infection, for some of them, nothing was left because of their extreme fatigue. And this happened not only in one patient but many more—too many for only [a] psychological cause.” Clinical laboratories continue to perform tests on patients experiencing symptoms of COVID-19 even after the acute illness has passed. (Photo copyright: AIGHD.)
Role of the Complement System
To complete their study, the Swiss scientists monitored 113 patients who were confirmed through a reverse transcriptase quantitative polymerase chain reaction (RT-qPCR) test to have COVID-19. The study also included 39 healthy control patients who were not infected.
The researchers examined 6,596 proteins in 268 blood samples collected when the sick patients were at an acute stage of the virus, and then again six months after the infection. They found that 40 of the patients who were sick with COVID-19 eventually developed symptoms of long COVID. Those 40 patients all had a group of proteins in their blood showing that the complement system of their immune system was still elevated even after recovering from the virus.
“Complement is an arm of the immune system that ‘complements’ the action of the other arms,” Amesh Adalja, MD, Adjunct Assistant Professor at Johns Hopkins Bloomberg School of Public Health, told Prevention, “Activities that it performs range from literally attacking the cell membranes of a pathogen to summoning the cells of other immune systems to the site of infection.”
In addition to helping bodies heal from injury and illness, the complement immune system also activates inflammation in the body—and if the complement system is activated for too long the patient is at risk for autoimmune disease and other inflammatory conditions.
Conducted by genetic scientists at Trinity College Dublin and St. James’ Hospital in Dublin, Ireland, the study “analyzed blood samples—specifically, serum and plasma—from 76 patients who were hospitalized with COVID-19 in March or April 2020, along with those from 25 people taken before the pandemic. The researchers discovered that people who said they had brain fog had higher levels of a protein in their blood called S100β [a calcium-binding protein] than people who didn’t have brain fog,” Prevention reported.
“S100β is made by cells in the brain and isn’t normally found in the blood. That suggests that the patients had a breakdown in the blood-brain barrier, which blocks certain substances from getting to the brain and spinal cord, the researchers noted,” Prevention reported.
“The scientists then did MRI scans with dye of 22 people with long COVID (11 of them who reported having brain fog), along with 10 people who recovered from COVID-19. They found that long COVID patients who had brain fog had signs of a leaky blood-brain barrier,” Prevention noted.
“This leakiness likely disrupts the integrity of neurons in the brain by shifting the delicate balance of materials moving into and out of the brain,” Matthew Campbell, PhD, Professor and Head of Genetics at Trinity College Dublin, told Prevention.
Interactions with Other Viruses
According to Medical News Today, the Swiss study results also suggest that long COVID symptoms could appear because of the reactivation of a previous herpesvirus infection. The patients in the study showed increased antibodies against cytomegalovirus, a virus that half of all Americans have contracted by age 40.
The link between long COVID and these other viruses could be key to developing treatment for those suffering with both illnesses. The antiviral treatments used for the herpesvirus could potentially help treat long COVID symptoms as well, according to Medical News Today.
“Millions of people across the planet have long COVID or will develop it,” Thomas Russo MD, Professor and Chief of Infectious Disease at the University at Buffalo in New York, told Prevention. “It’s going to be the next major phase of this pandemic. If we don’t learn to diagnose and manage this, we are going to have many people with complications that impact their lives for the long term.”
Long COVID won’t be going away any time soon, much like the COVID-19 coronavirus. But these two studies may lead to more effective clinical laboratory testing, diagnoses, and treatments for millions of people suffering from the debilitating condition.
Clinical laboratory managers should note that this company’s new diagnostic offering involving screening embryos for specific genetic conditions is not without controversy
Is the world ready for whole genome sequencing (WGS) of preimplantation embryos to help couples undergoing in vitro fertilization (IVF) treatments know if their embryos have potential genetic health problems? Orchid Health, a clinical preimplantation genetic testing (PGT) laboratory that conducts genetic screening in San Francisco, believes the answer is yes! But the cost is high, and the process is not without controversy.
According to an article in Science, Orchid’s service—a sequencings of the whole human genome of preimplantation embryos at $2,500 per embryo tested—“will look not just for single-gene mutations that cause disorders such as cystic fibrosis, but also more extensively for medleys of common and rare gene variants known to predispose people to neurodevelopmental disorders, severe obesity, and certain psychiatric conditions such as schizophrenia.”
However, Science also noted that some genomics researchers “claim the company inappropriately uses their data to generate some of its risk estimates,” adding that the “Psychiatric Genomics Consortium (PGC), an international group of more than 800 researchers working to decode the genetic and molecular underpinnings of mental health conditions, says Orchid’s new test relies on data [PGC] produced over the past decade, and that the company has violated restrictions against the data’s use for embryo screening.”
There are some who assert that a whole genome sequence of an embryo—given today’s state of genetic technology and knowledge—could generate information that cannot be interpreted accurately in ways that help parents and doctors make informed prenatal testing decisions. At the same time, criticisms expressed by the PGC raise reasonable points.
Perhaps this is a sign of the times. Orchid Health is the latest genetic testing company that is looking to get ahead of genetic testing competitors with its diagnostics offerings. Meanwhile, knowledgeable and credible experts question the appropriateness of this testing, given the genetic knowledge that exists today.
“This is a major advance in the amount of information parents can have,” Orchid’s founder and CEO Noor Siddiqui (above) told CNBC. “The way that you can use that information is really up to you, but it gives a lot more control and confidence into a process that, for all of history, has just been totally left to chance.” Should Orchid Health’s analysis prove useful, pediatricians could order further clinical laboratory prenatal testing to confirm and diagnose potential genetic diseases for parents. (Photo copyright: General Assembly.)
Orchid Receives World-class Support
Regardless of the pushback from some genetic researchers, Orchid has attracted several world-class geneticists and genetics investors to its board of advisors. They include:
Jacques Cohen, PhD, embryologist, co-founder and former director for genetics laboratory Reprogenetics LLC (now CooperGenomics).
Anne Wojcicki, co-founder and CEO of direct-to-consumer genetic testing company 23andMe.
and others.
The WGS test, according to Orchid, detects genetic errors in embryos that are linked to severe illnesses before a pregnancy even begins. And by sequencing 99% of an embryo’s DNA, the test can spot potential health risks that could affect a future baby.
According to its website, the PGT lab company uses the WGS data to identify both monogenic (single-gene) and polygenic (multiple-gene) diseases, including:
Orchid is not without its critics. Knowledgeable, credible experts have questioned the appropriateness of this type of genetic testing. They fear it could become a modern-day form of eugenics.
Andrew McQuillin, PhD, Professor of Molecular Psychiatry at University College London, has concerns about Orchid’s preimplantation genetic testing. He maintains that it is difficult to control how such data is used, and that even the most accurate sequencing techniques do not predict disease risk very well.
“[Polygenic risk scores are] useful in the research context, but at the individual level, they’re not actually terribly useful to predict who’s going to develop schizophrenia or not,” McQuillin told Science. “We can come up with guidance on how these things should be used. The difficulty is that official guidance like that doesn’t feature anywhere in the marketing from these companies.”
McQuillin also stated that researchers must have an extensive discussion regarding the implications of this type of embryo screening.
“We need to take a look at whether this is really something we should be doing. It’s the type of thing that, if it becomes widespread, in 40 years’ time, we will ask, ‘What on Earth have we done?’” McQuillin emphasized.
Redefining Reproduction
It takes about three weeks for couples to receive their report back from Orchid after completing the whole genome sequence of a preimplantation embryo. A board-certified genetic counselor then consults with the parents to help them understand the results.
Founder and CEO Noor Siddiqui hopes Orchid will be able to scale up its operations and introduce more automation to the testing process to the cost per embryo.
“We want to make this something that’s accessible to everyone,” she told CNBC.
“I think this has the potential to totally redefine reproduction,” she added. “I just think that’s really exciting to be able to make people more confident about one of the most important decisions of their life, and to give them a little bit more control.”
Clinical laboratories have long been involved in prenatal screening to gain insight into risk levels associated with certain genetic disorders. Even some of that testing comes with controversy and ambiguous findings. Whether Orchid Health’s PGT process delivers accurate, reliable diagnostic insights regarding preimplantation embryos remains to be seen.
New gene-editing systems could provide markedly improved accuracy for DNA and RNA editing leading to new precision medicine tools and genetic therapies
In what may turn out to be a significant development in genetic engineering, researchers from three institutions have identified nearly 200 new systems that can be used for editing genes. It is believed that a number of these new systems can provide comparable or better accuracy when compared to CRISPER (Clustered Regularly Interspaced Short Palindromic Repeats), currently the most-used gene editing method.
CRISPR-Cas9 has been the standard tool for CRISPR gene editing and genetic engineering. However, publication of these new research findings are expected to give scientists better, more precise tools to edit genes. In turn, these developments could lead to new clinical laboratory tests and precision medicine therapies for patients with inherited genetic diseases.
“Best known as a powerful gene-editing tool, CRISPR actually comes from an inbuilt defense system found in bacteria and simple microbes called archaea. CRISPR systems include pairs of ‘molecular scissors’ called Cas enzymes, which allow microbes to cut up the DNA of viruses that attack them. CRISPR technology takes advantage of these scissors to cut genes out of DNA and paste new genes in,” according to Live Science.
In its article, New Atlas noted that the researchers looked to bacteria because “In nature, CRISPR is a self-defense tool used by bacteria.” They developed an algorithm—called FLSHclust—to conduct “a deep dive into three databases of bacteria, found in environments as diverse as Antarctic lakes, breweries, and dog saliva.”
In their paper, the researchers wrote, “We developed fast locality-sensitive hashing–based clustering (FLSHclust), a parallelized, deep clustering algorithm with linearithmic scaling based on locality-sensitive hashing. FLSHclust approaches MMseqs2, a gold-standard quadratic-scaling algorithm, in clustering performance. We applied FLSHclust in a sensitive CRISPR discovery pipeline and identified 188 previously unreported CRISPR-associated systems, including many rare systems.”
“In lab tests [the newfound CRISPR systems] demonstrated a range of functions, and fell into both known and brand new categories,” New Atlas reported.
“Some of these microbial systems were exclusively found in water from coal mines,” Soumya Kannan, PhD (above), a Graduate Fellow at MIT’s Zhang Lab and co-first author of the study, told New Atlas. “If someone hadn’t been interested in that, we may never have seen those systems.” These new gene-editing systems could lead to new clinical laboratory genetic tests and therapeutics for chronic diseases. (Photo copyright: MIT McGovern Institute.)
Deeper Look at Advancement
The CRISPR-Cas9 made a terrific impact when it was announced in 2012, earning a Nobel Prize in Chemistry.
Though CRISPR-Cas9 brought huge benefits to genetic research, the team noted in their Science paper that “existing methods for sequence mining lag behind the exponentially growing databases that now contain billions of proteins, which restricts the discovery of rare protein families and associations.
“We sought to comprehensively enumerate CRISPR-linked gene modules in all existing publicly available sequencing data,” the scientist continued. “Recently, several previously unknown biochemical activities have been linked to programmable nucleic acid recognition by CRISPR systems, including transposition and protease activity. We reasoned that many more diverse enzymatic activities may be associated with CRISPR systems, many of which could be of low abundance in existing [gene] sequence databases.”
Among the previously unknown gene-editing systems the researchers found were some belonging to the Type 1 CRISPR systems class. These “have longer guide RNA sequences than Cas9. They can be directed to their targets more precisely, reducing the risk of off-target edits—one of the main problems with CRISPR gene editing,” New Atlas reported.
“The authors also identified a CRISPR-Cas enzyme, Cas14, which cuts RNA precisely. These discoveries may help to further improve DNA- and RNA-editing technologies, with wide-ranging applications in medicine and biotechnology,” the Science paper noted.
Testing also showed these systems were able to edit human cells, meaning “their size should allow them to be delivered in the same packages currently used for CRISPR-Cas9,” New Atlas added.
Another newfound gene-editing system demonstrated “collateral activity, breaking down nucleic acids after binding to the target, New Atlas reported. SHERLOCK, a tool used to diagnose single samples of RNA or DNA to diagnose disease, previously utilized this system.
Additionally, New Atlas noted, “a type VII system was found to target RNA, which could unlock a range of new tools through RNA editing. Others could be adapted to record when certain genes are expressed, or as sensors for activity in cells.”
Looking Ahead
The strides in science from the CRISPR-Cas9 give a hint at what can come from the new discovery. “Not only does this study greatly expand the field of possible gene editing tools, but it shows that exploring microbial ecosystems in obscure environments could pay off with potential human benefits,” New Atlas noted.
“This study introduces FLSHclust as a tool to cluster millions of sequences quickly and efficiently, with broad applications in mining large sequence databases. The CRISPR-linked systems that we discovered represent an untapped trove of diverse biochemical activities linked to RNA-guided mechanisms, with great potential for development as biotechnologies,” the researchers wrote in Science.
How these newfound gene-editing tools and the new FLSHclust algorithm will eventually lead to new clinical laboratory tests and precision medicine diagnostics is not yet clear. But the discoveries will certainly improve DNA/RNA editing, and that may eventually lead to new clinical and biomedical applications.
Genetic engineers at the lab used the new tool to generate a catalog of 71 million possible missense variants, classifying 89% as either benign or pathogenic
Genetic engineers continue to use artificial intelligence (AI) and deep learning to develop research tools that have implications for clinical laboratories. The latest development involves Google’s DeepMind artificial intelligence lab which has created an AI tool that, they say, can predict whether a single-letter substitution in DNA—known as a missense variant (aka, missense mutation)—is likely to cause disease.
The Google engineers used their new model—dubbed AlphaMissense—to generate a catalog of 71 million possible missense variants. They were able to classify 89% as likely to be either benign or pathogenic mutations. That compares with just 0.1% that have been classified using conventional methods, according to the DeepMind engineers.
This is yet another example of how Google is investing to develop solutions for healthcare and medical care. In this case, DeepMind might find genetic sequences that are associated with disease or health conditions. In turn, these genetic sequences could eventually become biomarkers that clinical laboratories could use to help physicians make earlier, more accurate diagnoses and allow faster interventions that improve patient care.
“AI tools that can accurately predict the effect of variants have the power to accelerate research across fields from molecular biology to clinical and statistical genetics,” wrote Google DeepMind engineers Jun Cheng, PhD (left), and Žiga Avsec, PhD (right), in a blog post describing the new tool. Clinical laboratories benefit from the diagnostic biomarkers generated by this type of research. (Photo copyrights: LinkedIn.)
AI’s Effect on Genetic Research
Genetic experiments to identify which mutations cause disease are both costly and time-consuming, Google DeepMind engineers Jun Cheng, PhD, and Žiga Avsec, PhD, wrote in a blog post. However, artificial intelligence sped up that process considerably.
“By using AI predictions, researchers can get a preview of results for thousands of proteins at a time, which can help to prioritize resources and accelerate more complex studies,” they noted.
Of all possible 71 million variants, approximately 6%, or four million, have already been seen in humans, they wrote, noting that the average person carries more than 9,000. Most are benign, “but others are pathogenic and can severely disrupt protein function,” causing diseases such as cystic fibrosis, sickle-cell anemia, and cancer.
“A missense variant is a single letter substitution in DNA that results in a different amino acid within a protein,” Cheng and Avsec wrote in the blog post. “If you think of DNA as a language, switching one letter can change a word and alter the meaning of a sentence altogether. In this case, a substitution changes which amino acid is translated, which can affect the function of a protein.”
In the Google DeepMind study, AlphaMissense predicted that 57% of the 71 million variants are “likely benign,” 32% are “likely pathogenic,” and 11% are “uncertain.”
The AlphaMissense model is adapted from an earlier model called AlphaFold which uses amino acid genetic sequences to predict the structure of proteins.
“AlphaMissense was fed data on DNA from humans and closely related primates to learn which missense mutations are common, and therefore probably benign, and which are rare and potentially harmful,” The Guardian reported. “At the same time, the program familiarized itself with the ‘language’ of proteins by studying millions of protein sequences and learning what a ‘healthy’ protein looks like.”
The model assigned each variant a score between 0 and 1 to rate the likelihood of pathogenicity [the potential for a pathogen to cause disease]. “The continuous score allows users to choose a threshold for classifying variants as pathogenic or benign that matches their accuracy requirements,” Avsec and Cheng wrote in their blog post.
However, they also acknowledged that it doesn’t indicate exactly how the variation causes disease.
The engineers cautioned that the predictions in the catalog are not intended for clinical use. Instead, they “should be interpreted with other sources of evidence.” However, “this work has the potential to improve the diagnosis of rare genetic disorders, and help discover new disease-causing genes,” they noted.
Genomics England Sees a Helpful Tool
BBC noted that AlphaMissense has been tested by Genomics England, which works with the UK’s National Health Service. “The new tool is really bringing a new perspective to the data,” Ellen Thomas, PhD, Genomics England’s Deputy Chief Medical Officer, told the BBC. “It will help clinical scientists make sense of genetic data so that it is useful for patients and for their clinical teams.”
AlphaMissense is “a big step forward,” Ewan Birney, PhD, Deputy Director General of the European Molecular Biology Laboratory (EMBL) told the BBC. “It will help clinical researchers prioritize where to look to find areas that could cause disease.”
Other experts, however, who spoke with MIT Technology Review were less enthusiastic.
Heidi Rehm, PhD, co-director of the Program in Medical and Population Genetics at the Broad Institute, suggested that the DeepMind engineers overstated the certainty of the model’s predictions. She told the publication that she was “disappointed” that they labeled the variants as benign or pathogenic.
“The models are improving, but none are perfect, and they still don’t get you to pathogenic or not,” she said.
“Typically, experts don’t declare a mutation pathogenic until they have real-world data from patients, evidence of inheritance patterns in families, and lab tests—information that’s shared through public websites of variants such as ClinVar,” the MIT article noted.
Is AlphaMissense a Biosecurity Risk?
Although DeepMind has released its catalog of variations, MIT Technology Review notes that the lab isn’t releasing the entire AI model due to what it describes as a “biosecurity risk.”
The concern is that “bad actors” could try using it on non-human species, DeepMind said. But one anonymous expert described the restrictions “as a transparent effort to stop others from quickly deploying the model for their own uses,” the MIT article noted.
And so, genetics research takes a huge step forward thanks to Google DeepMind, artificial intelligence, and deep learning. Clinical laboratories and pathologists may soon have useful new tools that help healthcare provider diagnose diseases. Time will tell. But the developments are certain worth watching.
Clinical laboratories and pathology groups can benefit from knowing how genetic testing is being used for other than medical testing purposes
It is useful for pathologists and clinical laboratory managers to be aware of the different ways genetic testing and DNA sequencing is being conducted. That’s because a genetic test for one purpose—such as identifying an individual’s relatives and connection to a region or a cultural group—might generate data that could become part of that person’s medical care.
Thus, an ongoing genetic study in South Africa highlighting the issue of so-called “helicopter research” will be informative for Dark Daily’s readers.
Also known as “neo-colonial science,” helicopter research describes when scientists from wealthy countries perform research in lower-income countries in ways that may be deemed exploitative or disrespectful to local populations.
“Scientists conduct helicopter research when they collect data from developing countries and marginalized communities with little to no involvement from local researchers and community members,” wrote researchers Dana Al-Hindi, and Brenna Henn PhD, in an article for The Conversation. “Helicopter research also occurs when researchers take data out of the country they collected it from without either providing benefit to or sharing the results with the community.”
In an article for The Conversation, UC Davis researchers Brenna Henn, PhD (left), and Dana Al-Hindi (right), wrote, “While we have learned a great deal from these communities, we have been unable to fulfill a common request: providing them their individual genetic ancestry result. In our attempts to overcome the logistical challenges of providing this information, we’ve grappled with the common question of how to ensure an equitable balance of benefits between researchers and the community they study. What we’ve found is that there is no easy answer.” Clinical laboratories will want to remember the term “Helicopter Research” in relation to these types of studies. (Photos copyright: UC Davis/The Conversation.)
The South Africa study, conducted over the past 12 years, aims to use genetic data “to help unravel the history and prehistory of southern Africans and their relationship to populations around the world,” the authors wrote in The Conversation.
The researchers have been using the genetic data to trace the ancestry of indigenous Khoekhoe and San peoples in South Africa as well as other populations that self-identify as “Colored.”
“Early European colonizers initially used this term to refer to indigenous Khoekhoe and San groups long before it was codified by the apartheid government in 1948,” the researchers wrote. “It persists today as an ethnic category, broadly encompassing Khoe-San groups, various East African, Indian, and Southeast Asian populations brought by the slave trade, and people of mixed ancestry.”
Challenges Sharing Genetic Data with Study Participants
Participants in the study have asked to see their personal genetic ancestry results, but the researchers noted several challenges, including local restrictions and the difficulty of presenting complex data in “an accessible and digestible form.” So, the researchers partnered with consumer-focused genetic testing company 23andMe (NASDAQ:ME).
23andMe provided additional funding for the research, assisted the researchers in community outreach, and “expanded our ability to ‘capacity-build’—that is, to make sure that the knowledge and skills we gain are shared with local institutions,” Henn and Al-Hindi wrote in The Conversation. They added that they are still dealing with questions about whether their efforts to provide equitable benefits are sufficient.
“Our research team, local collaborators, and 23andMe are all concerned about how to best address the risk of helicopter research, coercion, and any unknown risks that may arise from disclosing personal ancestry results,” they wrote.
Cape Town Statement on Fostering Research Integrity
The issue of helicopter research was a major focus at the 7th World Conference on Research Integrity (WCRI), held May 29-June 1 in Cape Town, South Africa. It was the first WCRI to be held in Africa and adopted the theme “Fostering Research Integrity in an Unequal World.”
One outcome of the conference will be an effort to produce what is known as the Cape Town Statement on Fostering Research Integrity. The statement will “highlight the importance of fairness in international research partnerships,” noted Research Professional News.
The statement “compels institutions and researchers alike to act on their responsibilities to promote equity, diversity, and fairness in research partnerships,” conference speaker Retha Visagie, DCur, told the publication. She leads the Research Integrity Office at the University of South Africa.
Conference co-chair Lyn Horn, PhD, director the Office of Research Integrity at the University of Cape Town, told the publication that it could take up to a year before a draft of the statement is ready for comment.
One overarching goal will be to “demonstrate why inequity and unfair practices in research collaborations and contexts is a research integrity (RI) matter,” the authors wrote. “Second it must identify some key values or principles and action guides that will address the issue of equity and fairness in research within the context of the complete research life cycle from research agenda setting and call to proposal development, through grant application, allocation and management of funding, data production, analysis, management and sharing, to outputs, translation, and evaluation.”
Another conference speaker, Francis Kombe PhD, told attendees the statement will offer guidance specifically to institutions such as universities, journals, and funding organizations, the journal Science reported. That stands in contrast to earlier statements on helicopter research, which were geared more toward individuals and small groups.
How any of this will impact clinical laboratories and pathology groups remains unclear. Nevertheless, it is worthwhile knowing how gene sequencing is being used by researchers for purposes other than to guide diagnoses and treatment of patients.
