Viral reservoir could be behind persistence, says study, which also suggests a blood biomarker could be found for clinical laboratory testing
Microbiologists and virologists working closely with physicians treating long COVID-19 patients will gain new insights in a study that found coronavirus spike protein in COVID-19 patients’ blood up to 12 months after diagnosis. The researchers believe their findings could be used to develop a clinical laboratory biomarker for long COVID-19.
Researchers at Brigham and Women’s Hospital and Massachusetts General Hospital said medical experts are not sure why some people have unwelcome symptoms weeks and months after a positive COVID-19 diagnosis, while others clear the infection without lingering effects.
The scientists believe if this work is validated, clinical laboratories might gain an assay to use in the diagnosis of long COVID-19.
“The half-life of spike protein in the body is pretty short, so its presence indicates that there must be some kind of active viral reservoir,” said David Walt, PhD (above), Professor of Pathology, Brigham and Women’s Hospital, and lead author of the study that found coronavirus spike protein in long COVID patients. The study findings indicate a potential clinical laboratory biomarker for long COVID-19. (Photo copyright: Brigham and Women’s Hospital.)
Viral Reservoir Possibly Behind Long COVID-19
The study suggests that SARS-CoV-2 finds a home in the body, particularly the gastrointestinal tract, “through viral reservoirs, where it continues to release spike protein and trigger inflammation,” Medical News Today reported.
Lead author of the study David Walt, PhD, Professor of Pathology, Brigham and Women’s Hospital and the Hansjörg Wyss Professor Biologically Inspired Engineering at Harvard Medical School, told The Guardian he “was motivated to carry out the study after earlier research by his colleagues detected genetic material from the COVID virus (viral RNA) in stool samples from children with multisystem inflammatory syndrome (a rare but serious condition that often strikes around four weeks after catching COVID) as well as spike protein and a marker of gut leakiness in their blood.”
Long COVID—also known as long-haul COVID, post-COVID-19, or its technical name, post-acute sequelae of COVID-19 or PASC—can involve health problems continuing weeks, months, or even years after a positive diagnosis, according to the federal Centers for Disease Control and Prevention (CDC).
Symptoms of long COVID, according to the researchers, include:
fatigue,
loss of smell,
memory loss,
gastrointestinal distress, and
shortness of breath.
“If someone could somehow get to that viral load and eliminate it, it might lead to resolution of symptoms,” Walt told the Boston Globe, which noted that the researchers may explore a clinical trial involving antiviral drugs for treatment of long COVID-19.
Clues from Earlier Studies on Long COVID-19
Medical conditions that persisted following a COVID-19 infection have been studied for some time. In fact, in an earlier study, Walt and others found children who developed a multisystem inflammation syndrome weeks after being infected by SARS-CoV-2, according to their 2021 paper published in The Journal of Clinical Investigation, titled, “Multisystem Inflammatory Syndrome in Children Is Driven by Zonulin-Dependent Loss of Gut Mucosal Barrier.”
Although these earlier studies provided clues, the cause of PASC remains unclear, the researchers noted. They planned to take a more precise look at PASC biology by using appropriate sampling and patient recruitment.
“Disentangling the complex biology of PASC will rely on the identification of biomarkers that enable classification of patient phenotypes. Here, we analyze plasma samples collected from PASC and COVID-19 patients to determine the levels of SARS-CoV-2 antigens and cytokines and identify a blood biomarker that appears in the majority of PASC patients,” the researchers wrote.
Finding a Marker of a Persistent Infection
The researchers used plasma samples from 63 people with a previous SARS-CoV-2 diagnosis (37 also had PASC), Medical News Today reported. Over a 12-month period, the researchers’ findings included:
Detection in 65% of PASC samples of full-length spike, S1 spike, and nucleocapsid throughout the year of testing.
Spike detected in 60% of PASC patient samples, and not found in the COVID-19 samples.
In an interview with Scientific American, bioengineer Zoe Swank PhD, post-doctoral researcher, Brigham and Women’s Hospital, and co-author of the study, said, “Our main hypothesis is that the spike protein is not causing the symptoms, but it’s just a marker that is released because you still have infection of some cells with SARS-CoV-2.”
In that article, Swank shared the scientists’ intent to do more research involving hundreds of samples over the course of the COVID-19 pandemic from many hospitals and people.
COVID-19 Not the Only Virus That Hangs On
Having a long-haul COVID-19 marker is a “game-changer,” according to an infectious disease expert who was not involved in the study.
“There has not so far been a clear, objective marker that is measurable in the blood of people experiencing long COVID-19,” Michael Peluso, MD, Assistant Professor, Medicine, University of California San Francisco, told Scientific American. “I hope their findings will hold up. It really would make a difference for a lot of people if a marker like this could be validated,” he added.
However, COVID-19 is not the only virus that could persist. Ebola also may linger in areas that skirt the immune system, such as the eye interior and central nervous system, according to a World Health Organization fact sheet.
Thus, medical laboratory leaders may want to follow the Brigham and Women’s Hospital research to see if the scientists validate their finding, discover a biomarker for long-haul COVID-19, and pursue a clinical trial for antiviral drugs. Such discoveries could have implications for how diagnostic professionals work with physicians to care for long COVID patients.
Two studies show the accuracy of perception-based systems in detecting disease biomarkers without needing molecular recognition elements, such as antibodies
Researchers from multiple academic and research institutions have collaborated to develop a non-conventional machine learning-based technology for identifying and measuring biomarkers to detect ovarian cancer without the need for molecular identification elements, such as antibodies.
Traditional clinical laboratory methods for detecting biomarkers of specific diseases require a “molecular recognition molecule,” such as an antibody, to match with each disease’s biomarker. However, according to a Lehigh University news release, for ovarian cancer “there’s not a single biomarker—or analyte—that indicates the presence of cancer.
“When multiple analytes need to be measured in a given sample, which can increase the accuracy of a test, more antibodies are required, which increases the cost of the test and the turnaround time,” the news release noted.
Unveiled in two sequential studies, the new method for detecting ovarian cancer uses machine learning to examine spectral signatures of carbon nanotubes to detect and recognize the disease biomarkers in a very non-conventional fashion.
“Carbon nanotubes have interesting electronic properties,” said Daniel Heller, PhD (above), in the Lehigh University news release. “If you shoot light at them, they emit a different color of light, and that light’s color and intensity can change based on what’s sticking to the nanotube. We were able to harness the complexity of so many potential binding interactions by using a range of nanotubes with various wrappings. And that gave us a range of different sensors that could all detect slightly different things, and it turned out they responded differently to different proteins.” This method differs greatly from traditional clinical laboratory methods for identifying disease biomarkers. (Photo copyright: Memorial Sloan-Kettering Cancer Center.)
Perception-based Nanosensor Array for Detecting Disease
In the Science Advances paper, the researchers described their development of “a perception-based platform based on an optical nanosensor array that leverages machine learning algorithms to detect multiple protein biomarkers in biofluids.
“Perception-based machine learning (ML) platforms, modeled after the complex olfactory system, can isolate individual signals through an array of relatively nonspecific receptors. Each receptor captures certain features, and the overall ensemble response is analyzed by the neural network in our brain, resulting in perception,” the researchers wrote.
“This work demonstrates the potential of perception-based systems for the development of multiplexed sensors of disease biomarkers without the need for specific molecular recognition elements,” the researchers concluded.
In the Nature Biomedical Engineering paper, the researchers described a fined-tuned toolset that could accurately differentiate ovarian cancer biomarkers from biomarkers in individuals who are cancer-free.
“Here we show that a ‘disease fingerprint’—acquired via machine learning from the spectra of near-infrared fluorescence emissions of an array of carbon nanotubes functionalized with quantum defects—detects high-grade serous ovarian carcinoma in serum samples from symptomatic individuals with 87% sensitivity at 98% specificity (compared with 84% sensitivity at 98% specificity for the current best [clinical laboratory] screening test, which uses measurements of cancer antigen 125 and transvaginal ultrasonography,” the researchers wrote.
“We demonstrated that a perception-based nanosensor platform could detect ovarian cancer biomarkers using machine learning,” said Yoona Yang, PhD, a postdoctoral research associate in Lehigh’s Department of Chemical and Biomolecular Engineering and co-first author of the Science Advances article, in the news release.
How Perception-based Machine Learning Platforms Work
According to Yang, perception-based sensing functions like the human brain.
“The system consists of a sensing array that captures a certain feature of the analytes in a specific way, and then the ensemble response from the array is analyzed by the computational perceptive model. It can detect various analytes at once, which makes it much more efficient,” Yang said.
“SWCNTs have unique optical properties and sensitivity that make them valuable as sensor materials. SWCNTS emit near-infrared photoluminescence with distinct narrow emission bands that are exquisitely sensitive to the local environment,” the researchers wrote in Science Advances.
“Carbon nanotubes have interesting electronic properties,” said Daniel Heller, PhD, Head of the Cancer Nanotechnology Laboratory at Memorial Sloan Kettering Cancer Center and Associate Professor in the Department of Pharmacology at Weill Cornell Medicine of Cornell University, in the Lehigh University news release.
“If you shoot light at them, they emit a different color of light, and that light’s color and intensity can change based on what’s sticking to the nanotube. We were able to harness the complexity of so many potential binding interactions by using a range of nanotubes with various wrappings. And that gave us a range of different sensors that could all detect slightly different things, and it turned out they responded differently to different proteins,” he added.
The researchers put their technology to practical test in the second study. The wanted to learn if it could differentiate symptomatic patients with high-grade ovarian cancer from cancer-free individuals.
The research team used 269 serum samples. This time, nanotubes were bound with a specific molecule providing “an extra signal in terms of data and richer data from every nanotube-DNA combination,” said Anand Jagota PhD, Professor, Bioengineering and Chemical and Biomolecular Engineering, Lehigh University, in the news release.
This year, 19,880 women will be diagnosed with ovarian cancer and 12,810 will die from the disease, according to American Cancer Society data. While more research and clinical trials are needed, the above studies are compelling and suggest the possibility that one day clinical laboratories may detect ovarian cancer faster and more accurately than with current methods.
All-of-Us program is free to participants and provides data to more than 800 research studies for cancer, COVID-19, Alzheimer’s, and other diseases; findings will lead to new biomarkers for clinical laboratory tests
It is hard to say no to free. At least that is what the National Institutes of Health (NIH) is counting on to help increase the size and diversity of its database of genetic sequences. The NIH’s All-of-Us Research Program is offering free genetic testing for all participants in the program, as well as free wearable Fitbits for those selected to provide lifestyle and behavior data.
Many pathologists and clinical laboratory managers know that this group of researchers hope to build a database of more than one million genetic sequences to better understand “how certain genetic traits affect underrepresented communities, which could greatly affect the future of customized healthcare,” CBS affiliate 8 News Now reported.
“Customized healthcare” is a euphemism for precision medicine, and genetic sequencing is increasingly playing a key role in the development of personalized diagnostics and therapeutics for cancer and other deadly diseases.
In “VA’s ‘Million Veterans Program’ Research Study Receives Its 100,000th Human Genome Sequence,” Dark Daily described how the NIH’s All-of-Us program was launched in 2018 to aid research into health outcomes influenced by genetics, environments, and lifestyle. At that time, the program had biological samples from more than 270,000 people with a goal of one million participants.
Matthew Thombs, Senior Project Manager of Digital Health Technology at Scripps Research in La Jolla, Calif., joined the All-of-Us program after losing a family member “to a condition I believe could have been managed with changes to their lifestyle,” he told 8 News Now.
“What we are building will empower researchers with the information needed to make such conclusions (about possible need to change lifestyles) and forever alter how diseases are treated,” he added. “I hope that what we are doing here will help my son grow up in a world where healthcare is more of a priority, and many of the ailments we see today are things of the past.”
Such genetic testing could discover biomarkers for future personalized clinical laboratory diagnostics and drug therapies, a key aspect of precision medicine.
The photo above shows an All-of-Us participant being prepped to provide a biological sample for genetic testing. According to Matthew Thombs, Senior Project Manager of Digital Health Technology at Scripps Research, “participants can provide as much or as little information as they like, every single data point matters.” The collected data is shared anonymously with more than 800 research studies for COVID-19, Alzheimer’s, cancer, and other diseases, 8 News Now reported. (Photo copyright: KLAS-TV.)
Scripps Research Integrates Mobile Health Technology into All-of-Us Program
A critical aspect of the NIH’s research is determining how people’s behavior combined with their genetics may predispose them to certain diseases. Nonprofit research institution Scripps Research is working with the NIH’s All of Us Research Program to enroll and collect biological samples from one million US residents.
In addition, Scripps is fitting study participants with wearable mobile health devices to capture data on their habits and lifestyles.
“Until now, the treatment and prevention of disease has been based on a ‘one-size-fits-all’ approach, with most therapeutics tailored for the ‘average patient’. However, advances in genomic sequencing, mobile health technologies, and increasingly sophisticated informatics are ushering in a new era of precision medicine. This new approach takes into account differences in people’s genes, environment, and lifestyles giving medical professionals resources to design targeted treatments and prevention strategies for the individual,” Scripps states on its website.
Can wearable fitness devices and related data contribute to research on genetics and healthcare outcomes? Scripps aims to find out. It has fitted 10,000 people in the All-of-Us program with Fitbit devices (Fitbit Charge 4 tracker or Fitbit Versa 3 smartwatch) at no cost. Since February, Scripps has distributed 10,000 Fitbit wearable devices through the All-of-Us program.
“By sharing information about their health, habits, and environment, participants will help researchers understand why people get sick or stay healthy,” the Scripps website adds.
The Scripps researchers plan to analyze how the people use the wearable devices. They are also accumulating data about participants’ physical activity, heart rate, sleep, and other health metrics and outcomes “as part of the broader All of Us program,” a Scripps news release explained.
“This is the first time All of Us is distributing devices to participants. Our goal is to better understand how participants engage during research studies in order to continually improve user experience and participation. We also expect to learn more about how wearable data may inform the personalization of healthcare,” said Julia Moore Vogel, PhD, Director of The Participant Center at the All of Us Research Program at Scripps Research, in the news release.
All-of-Us Program Records ‘Significant Progress in Participant Diversity’
As of June, the NIH has enrolled 386,000 participants into the All-of-Us program, with 278,000 consenting to all of the program’s steps. Eighty percent of biological samples in the collection are from people in communities that have been under-represented in previous biomedical research an NIH new release noted. According to the NIH, that gives the All-of-Us research program “the most diverse dataset.”
What will all this research ultimately bring to clinical laboratories? Who knows? Nevertheless, if federal institutions like the NIH and non-profit research companies like Scripps believe precision medicine is worth investing in, then the All-of-Us program is worth watching.
A diverse database of a million genetic sequences combined with lifestyle and behavioral data may lead to new and improved personalized diagnostics and drug therapies.
The researchers believe their test ‘could reduce the number of unnecessary prostate cancer biopsies by 32%,’ UEA reported
New diagnostic technologies may make it possible for men to provide a urine sample that can allow a clinical laboratory to not only accurately diagnose prostate cancer but also help determine whether it is an aggressive form of prostate cancer. Researchers in the United Kingdom (UK) recently described just such a test in an online, peer-reviewed journal.
Development of a non-invasive method of diagnosing prostate cancer would be significant for anatomic pathologists in the United States. In the US alone, approximately 248,000 men will be diagnosed with this type of cancer in 2021. Prostate biopsies represent a major proportion of case referrals to community pathology groups.
Moreover, were such a non-invasive test for prostate cancer also able to identify those individuals with fast-growing prostate cancers, that would help urologists make more informed treatment decisions.
A Disease Men More Commonly Die ‘With’ Rather than ‘From’
According to CDC statistics, most men over the age of 80 will have some form of slow-growing prostate cancer when they die. However, a percentage of men each year contract a rapidly growing aggressive form of the cancer, and until recently, diagnosing which cancer a patient was fighting often required multiple invasive prostate needle biopsies. But that may soon change.
Researchers at the University of East Anglia (UEA) Norwich Medical School in the United Kingdom (UK) have developed a non-invasive urine test for prostate cancer that they say also can determine the aggressiveness of the disease. Knowing this may help physicians better assess a patient’s risk prior to ordering invasive needle biopsies, a UEA article notes.
The UEA test may also allow for self-collection of the biological sample, and if it proves accurate, the test could bring additional revenue to clinical laboratories that would perform the urine testing.
“In this work we develop a test that predicts whether a patient has prostate cancer and how aggressive the disease is from a urine sample. This model combines the measurement of a protein-marker called EN2 and the levels of 10 genes measured in urine and proves that integration of information from multiple, non-invasive biomarker sources has the potential to greatly improve how patients with a clinical suspicion of prostate cancer are risk-assessed prior to an invasive biopsy,” they wrote.
“While prostate cancer is responsible for a large proportion of all male cancer deaths, it is more commonly a disease men die with rather than from,” said Daniel Brewer, PhD, one of the lead researchers on this study. “Therefore, there is a desperate need for improvements in diagnosing and predicting outcomes for prostate cancer patients to minimize over-diagnosis and overtreatment whilst appropriately treating men with aggressive disease, especially if this can be done without taking an invasive biopsy.
“Invasive biopsies come at considerable economic, psychological, and societal cost to patients and healthcare systems alike,” he added. Brewer is Senior Lecturer in Cancer Bioinformatics and a group leader within the Cancer Genetics Team at UEA’s Norwich Medical School.
“Our new urine test not only shows whether a patient has prostate cancer, but it importantly shows how aggressive the disease is. This allows patients and doctors to select the correct treatment,” said Daniel Brewer, PhD (above), Senior Lecturer and Lead Researcher, UEA Norwich Medical School, in the news release. (Photo copyright: Eastern Daily Press.)
Possibility of Reducing Needle Biopsies by 32%
Called “ExoGrail,” the UEA’s new test builds on their earlier development of the Prostate Urine Risk (PUR) and ExoMeth tests. The test works by integrating two biomarkers.
Levels of gene expression of 10 genes related to prostate cancer.
The researchers tested ExoGrail on urine samples from 207 patients at Norfolk and Norwich University Hospital (NNUH) who also had needle biopsy samples available.
According to the published study, the UEA ExoGrail urine test enabled:
Results comparable to the biopsy findings.
Identification of people with prostate cancer and people without it.
Risk scoring that noted aggressive prostate cancer and need for biopsy.
Potential to reduce unnecessary biopsies by 32%.
“ExoGrail resulted in accurate predictions even when serum PSA [protein-specific antigen] levels alone proved inaccurate; patients with a raised PSA but negative biopsy result possessed ExoGrail scores significantly different from both clinically benign patients and those with low-grade Gleason 6 disease, whilst still able to discriminate between more clinically significant Gleason ≥ 7 cancers,” the researchers stated in their published study.
“The adoption of ExoGrail into current clinical pathways for reducing unnecessary biopsies was considered, showing the potential for up to 32% of patients to safely forgo an invasive biopsy without incurring excessive risk,” they noted.
Prostate Cancer Patients May Soon Have Options
While more research is needed, the new UEA Norwich Medical School ExoGrail test introduces compelling non-invasive methods for diagnosing prostate cancer. Patients with findings of aggressive cancer can proceed to biopsies, while others determined to have non-aggressive forms of prostate cancer may be able to avoid more invasive tests and the associated costs and stress.
Additionally, men may soon be able to collect their own specimens without the need to visit the primary care doctor or a patient service center.
A follow-up study underway at the University of East Anglia and the NNUH involves sending 2,000 men in the UK, Europe, and Canada home testing “prostate screening boxes” to “to collect men’s urine samples at-home,” according to a UEA new release, which noted that “the Prostate Screening Box has been developed in collaboration with REAL Digital International Limited to create a kit that fits through a standard letterbox.”
“We have developed the PUR (Prostate Urine Risk) test, which looks at gene expression in urine samples and provides vital information about whether a cancer is aggressive or ‘low risk,’” said Jeremy Clark, PhD, Senior Research Associate at UEA’s Norwich Medical School.
“The Prostate Screening Box part sounds like quite a small innovation, but it means that in future the monitoring of cancer in men could be so much less stressful for them and reduce the number of expensive trips to the hospital,” he added.
Anatomic pathologists and clinical laboratory managers will want to follow the progress of these clinical studies. A non-invasive, urine-based test for prostate cancer could be a game-changer if it can detect prostate cancer with comparable accuracy to the tissue-based diagnostics that are the current standard of care in the diagnosis of prostate cancer.
With improved genetic sequencing comes larger human genome databases that could lead to new diagnostic and therapeutic biomarkers for clinical laboratories
As the COVID-19 pandemic grabbed headlines, the human genome database at the US Department of Veterans Affairs Million Veterans Program (MVP) quietly grew. Now, this wealth of genomic information—as well as data from other large-scale genomic and genetic collections—is expected to produce new biomarkers for clinical laboratory diagnostics and testing.
In December, cancer genomics company Personalis, Inc. (NASDAQ:PSNL) of Menlo Park, Calif., achieved a milestone and delivered its 100,000th whole human genome sequence to the MVP, according to a news release, which also states that Personalis is the sole sequencing provider to the MVP.
The VA’s MVP program, which started in 2011, has 850,000 enrolled veterans and is expected to eventually involve two million people. The VA’s aim is to explore the role genes, lifestyle, and military experience play in health and human illness, notes the VA’s MVP website.
Health conditions affecting veterans the MVP is researching include:
The VA has contracted with Personalis through September 2021, and has invested $175 million, Clinical OMICS reported. Personalis has earned approximately $14 million from the VA. That’s about 76% of the company’s revenue, according to 2nd quarter data, Clinical OMICS noted.
“The VA MVP is the largest whole genome sequencing project in the United States, and this is a significant milestone for both the program and for Personalis,” said John West (above with wife Judy), Founder and CEO of Personalis, in the news release. “Population-scale sequencing projects of this nature represent a cornerstone in our effort to accelerate the advancement of precision medicine across a wide range of disease areas,” he added. (Photo copyright: MIT Technology Review.)
Database of Veterans’ Genomes Used in Current Research
What has the VA gained from their investment so far? An MVP fact sheet states researchers are tapping MVP data for these and other veteran health-related studies:
Differentiating between prostate cancer tumors that require treatment and others that are slow-growing and not life-threatening.
How genetics drives obesity, diabetes, and heart disease.
How data in DNA translates into actual physiological changes within the body.
Gene variations and patients’ response to Warfarin.
NIH Research Program Studies Effects of Genetics on Health
Another research program, the National Institutes of Health’s All of Us study, recently began returning results to its participants who provided blood, urine, and/or saliva samples. The NIH aims to aid research into health outcomes influenced by genetics, environment, and lifestyle, explained a news release. The program, launched in 2018, has biological samples from more than 270,000 people with a goal of one million participants.
“We’re changing the paradigm for research. Participants are our most important partners in this effort, and we know many of them are eager to get their genetic results and learn about the science they’re making possible,” said Josh Denny, MD, CEO of the NIH’s All of Us research program in the news release. Denny, a physician scientist, was Professor of Biomedical Informatics and Medicine, Director of the Center for Precision Medicine and Vice President for Personalized Medicine at Vanderbilt University Medical Center prior to joining the NIH. (Photo copyright: National Institutes of Health.)
Inclusive Data Could Aid Precision Medicine
The news release notes that more than 80% of biological samples in the All of Us database come from people in communities that have been under-represented in biomedical research.
“We need programs like All of Us to build diverse datasets so that research findings ultimately benefit everyone,” said Brad Ozenberger, PhD, All of Us Genomics Program Director, in the news release.
Precision medicine designed for specific healthcare populations is a goal of the All of Us program.
“[All of Us is] beneficial to all Americans, but actually beneficial to the African American race because a lot of research and a lot of medicines that we are taking advantage of today, [African Americans] were not part of the research,” Chris Crawford, All of US Research Study Navigator, told the Birmingham Times. “As [the All of Us study] goes forward and we get a big diverse group of people, it will help as far as making medicine and treatment that will be more precise for us,” he added.
Large Databases Could Advance Care
Genome sequencing technology continues to improve. It is faster, less complicated, and cheaper to sequence a whole human genome than ever before. And the resulting sequence is more accurate.
Thus, as human genome sequencing databases grow, researchers are deriving useful scientific insights from the data. This is relevant for clinical laboratories because the new insights from studying bigger databases of genomic information will produce new diagnostic and therapeutic biomarkers that can be the basis for new clinical laboratory tests as well as useful diagnostic assays for anatomic pathologists.
