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.
End of social distancing, masking, and other COVID-19 pandemic mitigations may lead to more severe flu-like infections in northern hemisphere, experts say
Clinical laboratory professionals in the United States and Canada should prepare now for a severe flu season. That is according to infectious disease experts at Johns Hopkin’s Center for Health Security who predict the rise in influenza (flu) cases in Australia signals what will likely be higher than normal numbers of flu-like infections starting this fall in the Northern Hemisphere.
As a Southern Hemisphere nation, Australia experiences winter from June through August. The land down under just concluded its worst flu season in five years. The flu arrived earlier than usual and was severe. Surveillance reports from the Aussie government’s Department of Health and Aged Care noted that influenza-like illness (ILI) peaked in May and June, but that starting in mid-April 2022 the weekly number of flu cases exceeded the five-year average.
If the same increase in flu cases happens here, healthcare systems and clinical laboratories already burdened with continuing COVID-19 testing and increasing demand for monkeypox testing could find the strain unbearable.
Amesh Adalja, MD (above), Infectious Disease Expert and Senior Scholar at the Johns Hopkin’s Center for Health Security, told Prevention that Australia’s flu season is typically a harbinger of what will follow in the US, Canada, and other Northern Hemisphere countries. “The planet has two hemispheres which have opposite respiratory viral seasons,” he said. “Therefore, Australia’s flu season—which is just ending—is often predictive of what will happen in the Northern Hemisphere.” Clinical laboratories in the United States should review their preparations as North America enters its influenza season. (Photo copyright: Johns Hopkins Bloomberg School of Public Health.)
Consequences of Decline in Flu Vaccinations and Social Distancing, Masks
The New York Times noted that in 2017, when Australia suffered through its worst flu season since modern surveillance techniques were adopted, the US experienced a deadly 2017-2018 flu season a half-year later that took an estimated 79,000 lives.
While the number of flu cases in this country is currently low, according to the weekly US Centers for Disease Control and Prevention’s (CDC) “Flu View,” that is expected to change as temperatures cool.
During the height of the COVID-19 pandemic in the US, influenza was nearly nonexistent. Pandemic-mitigation efforts such as masking, social distancing, and quarantining slowed the spread of the annual respiratory illness. But pandemic mitigation efforts are no longer the norm.
“Many have stopped masking,” said Abinash Virk MD, an Infectious Diseases Specialist at Mayo Clinic College of Medicine and Science, in a Mayo Clinic news blog that urged patients to get vaccinated for flu. “For the large part, we will see the re-emergence of influenza in the winter. In comparison, in 2020 winter … there was literally no influenza. But now that has all changed.”
Diminished Immunity Will Lead to More Severe Flu Cases
A CDC report published in July also noted that last winter’s flu season broke from the traditional pattern of arrival of the flu in the fall followed by a peak in cases in February.
During the 2021-22 season, influenza activity began to increase in November and remained elevated until mid-June. It featured two distinct waves, with A(H3N2) viruses predominating for the entire season. But the overall case counts were the lowest in at least 25 years preceding the COVID-19 pandemic.
Thomas Russo, MD, Professor and Chief of Infectious Disease at the University at Buffalo in New York, said the past two mild flu seasons could set the stage for a difficult year in 2022-23.
“Immunity to respiratory viruses, including the flu, wanes over time,” Russo told Prevention. “People have not seen the virus naturally for a couple of years and many individuals don’t get the flu vaccine.” That, he says, raises the risk that people who are unvaccinated against the flu will develop more severe cases if they do happen to get infected.
“People are interacting closely again and there are very few mandates,” he added. “That’s a set-up for increased transmission of influenza and other respiratory viruses.”
“The Southern Hemisphere has had a pretty bad flu season, and it came on early,” Fauci, told Bloomberg in late August. “Influenza, as we all have experienced over many years, can be a serious disease, particularly when you have a bad season.”
CNN reported that US government modeling predicts flu will peak this year in early December.
CDC Advises Public to Get Flu Vaccine
Because COVID-19 and Influenza have many symptoms in common, such as fever, cough, shortness of breath, fatigue, sore throat, runny nose, headache, and muscle aches, the Mayo Clinic points out on its blog that testing is the only way to discern between the two when symptoms overlap.
According to the CDC, the best way to reduce risk from seasonal flu and its potentially serious complications is to get vaccinated every year. The best time to get vaccinated for the flu is in September and October before the flu starts spreading in communities, the CDC states. However, vaccination after October can still provide protection during the peak of flu season.
Yet, many people fail to get the flu vaccine even though it is recommended for everyone over the age of six months. CNN reported that just 45% of Americans got their flu shots last season. Flu vaccination rates fell for several at-risk groups, including pregnant women and children.
Though flu seasons are often unpredictable, clinical laboratories should prepare now for an influx of influenza test specimens and higher case rates than the past two pandemic-lightened flu seasons. Coupled with COVID-19 and monkeypox testing, already strained supply lines may be disrupted.
Though only in early stages, findings could lead to a ‘therapeutic against current and newly-arising variants,’ say researchers
As SARS-CoV-2 changes and mutates, some therapeutic antibodies that were once highly effective in fighting the virus have lost potency. But now, in a proof-of-concept study, researchers from Boston Children’s Hospital have identified one antibody that neutralizes all known variants of the coronavirus, including the omicron variant. Microbiologists and clinical laboratory managers will find this intriguing, as most medical labs perform serology testing for SARS-CoV-2 antibodies.
The new antibody appears to be robust. It triggers several other types of antibodies as part of the immune response. If validated by further research, this discovery, the researchers state, may lead to new vaccines, better therapies, and improved treatments for COVID-19.
“We hope that this humanized antibody will prove to be as effective at neutralizing SARS-CoV-2 in patients as it has proven to be thus far in preclinical evaluations,” said geneticist Frederick Alt, PhD, Director of the Program in Cellular and Molecular Medicine at Boston Children’s Hospital and one of the leaders of the research. Clinical laboratories that perform serology testing for COVID-19 will be intrigued by this new line of research. (Photo copyright: PR Newswire.)
SP1-77 Antibody Outperforms All Others at Neutralizing SARS-CoV-2
To conduct their research, the team used genetically modified mice that basically have built-in human immune systems. These mice were originally utilized for seeking out antibodies to HIV, another virus that tends to mutate. Their immune systems can mimic what human immune systems encounter when a viral invader attacks.
The scientists inserted two human gene segments into the mice, which quickly produced antibodies resembling those made by humans. The mice were then exposed to the SARS-CoV-2 spike protein from the original coronavirus strain. The scientists found that the mice produced nine different families of antibodies that could bind to the spike protein.
The researchers then tested the effectiveness of those antibodies and found that three of the nine antibody families strongly neutralized the original SARS-CoV-2 coronavirus. In addition, one of the antibody families—dubbed SP1-77—was much more powerful and could neutralize the Alpha, Beta, Gamma, Delta, and all known Omicron strains of the SARS-CoV-2 virus.
New Monoclonal Antibody Products and Vaccines
If their findings are validated through further research, SP1-77 “would have potential to be a therapeutic against current and newly-arising variants of concern” according to the Science Immunology study. It also could be useful as part of a cocktail containing other antibody treatments for COVID-19 variants.
“SP1-77 binds the spike protein at a site that so far has not been mutated in any variant, and it neutralizes these variants by a novel mechanism,” said Tomas Kirchhausen, PhD, Senior Investigator, Program in Cellular and Molecular Medicine at Boston Children’s Hospital and one of the authors of the study in a statement announcing the study findings. “These properties may contribute to its broad and potent activity,” he added.
“This is very early-stage proof-of-concept work to illustrate that broadly neutralizing antibodies can be generated using a mouse model,” Amesh Adalja, MD, an infectious disease expert and senior scholar at the Johns Hopkins Center for Health Security, told Prevention. “Such work, if replicated and expanded, could form the basis of new monoclonal antibody products as well as a vaccine.”
The researchers have applied for a patent for the SP1-77 antibody as well as the mouse model they used to create it. Studies on the antibody are ongoing and have only been performed on mice and not humans. The scientists intend to execute further research on the innovative antibody and hope it will someday be used to help fight the COVID-19 virus and all its variants.
“We’d love to have a vaccine that is active against all circulating variants, including those yet to come,” Thomas Russo, MD, Professor and Chief of Infectious Disease, Department of Medicine, University at Buffalo told Prevention. “It’s the holy grail of vaccines.”
Microbiologists and clinical laboratories working with monoclonal antibodies to treat for COVID-19 infections will no doubt want to follow the Boston Children’s Hospital research closely as it may lead to new treatments and vaccines.
