Theranos is history, but big breakthroughs in blood testing are coming
Medical researchers say that within a few years, major breakthroughs in blood test technology that use the immune system’s response and genetic analysis to identify disease quickly and cost effectively will be on the market.
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One morning in May, Tayah Fernandes’ mother Shannon realized her four-year-old daughter was seriously ill and rushed her to the nearest emergency room in the English city of Manchester. The coronavirus had crashed onto UK shores weeks earlier, and emergency doctors were initially unsure how best to treat Tayah’s constellation of symptoms, which included stomach pain and a bright red rash.
They gave her antibiotics for a suspected bacterial infection, but her condition only got worse, her fever skyrocketing. For her parents, for all parents, it was the ultimate medical nightmare; doctors in the dark for days on the cause of their daughter’s illness.
Eventually, after further blood tests, doctors decided Tayah was suffering from an unusual inflammatory syndrome that pediatric infectious disease specialists had just started to see, but suspected to have links to Sars-COV-2. .
Young patients from the UK and US were arriving in intensive care units with symptoms similar to another disease already recognized by doctors, called Kawasaki. But they had no guarantee that the same treatment – injecting a solution of donor antibodies into the bloodstream – would work.
In Tayah’s case, the antibody solution, known as immunoglobulin, worked, much to her parents’ relief. But around the same time last May, a team of researchers at Imperial College London confirmed, through complex analyzes of blood samples taken from patients like Tayah, that it was well of a new disease, distinct from Kawasaki’s.
A related breakthrough in this same lab, focused specifically on the behavior of individual genes, could have seismic implications for a multibillion-dollar diagnostic industry that has received unprecedented attention from patients, regulators and the world. of business during this pandemic.
New method of identifying a specific disease from blood samples relies on the correlation between the activity of a small set of genes, which represents the immune response, and specific pathogens that cause a specific disease – just as the poliovirus causes polio, the coronavirus (SARS -COV-2, a pathogen) causes Covid-19. Scientists believe that by studying a small number of genes, they can quickly discern which pathogen is in a patient’s system, what disease they are suffering from, and how best to treat it.
From companies, from small companies spun off from research universities to industry giants like Abbott Laboratories and DanaherThe Cepheids seek to build on two decades of research into how our own immune system responds naturally to foreign substances in our bodies, including pathogens like bacteria or viruses. Current technology like Cepheid’s GeneXpert technology is able to distinguish between the different RNAs of various viruses, such as SARS-COV-2, or a particular strain of influenza, but experts say it is increasingly clear that our body’s immune system can be faster, more accurate detection systems.
Historically, doctors have had to rely on a patient’s history and symptoms to determine the cause of illness and develop a treatment plan. More recently, molecular-level laboratory inspections such as Cepheid technology have enabled clinicians to identify specific pathogens in nasal mucus, throat swabs, or blood samples that may have caused disease. But finding a bacteria or virus this way can be time consuming, expensive, and sometimes just ineffective. A virus-specific RNA signature can be difficult to detect.
Abbott and Cepheid did not respond to requests for comment.
The team at Imperial College London, working separately but at the same time as several counterparts around the world, are now confident that future diagnoses can soon be made using tabletop tests that will only take a few minutes.
These tests would not explicitly screen for a specific pathogen, but rather allow scientists and healthcare professionals to simply observe how specific genes in the body behave as an indication of how an immune system is already responding to a pathogen. which might not be easily otherwise. detectable.
Imperial College professor Mike Levin is currently leading an ongoing EU-funded study focusing on this potential called “Diamonds”. In recent years, he and other scientists have shown how the activity seen in a small number of our genes can work as a kind of shortcut for our body’s immune response to a pathogen. If a handful of specific genes out of the thousands in a blood sample are turned on – or conversely, inhibited – it may indicate that a person is preparing to fight a specific pathogen.
Levin and his colleagues already have a proof of concept for this diagnostic approach after studies involving thousands of patients with fever caused by tuberculosis and hundreds of Kawasaki patients. And his team at Imperial College’s work with the “Diamonds” study is starting to bear fruit and could help identify distinct immunologic markers of diseases like coronavirus-related multisystem inflammatory syndrome in children like Tayah Fernandes, now. commonly referred to as MIS-C.
When Covid-19 emerged in multiple locations, with MIS-C in its wake, it offered Levin and his researchers an unprecedented opportunity to test this technique on a brand new disease.
In the future, these tests – relying on huge amounts of data and machine learning – should be able to produce multi-class results rather than just binary. This means that they could not only confirm whether a pathogen is bacterial or viral, or whether someone has a specific disease or not, but could also distinguish which of a multitude of diseases is afflicting their patient.
In short, Levin expects that by examining the behavior of a relatively small number of genes, clinicians will be able to assign patients to all major disease classes within an hour.
“We think it’s a completely revolutionary way to make a medical diagnosis,” Levin said. He expects research to provide the basis for a new technology, but has no financial interest in any endeavor related to it.
Rather than what he calls the “step-by-step process” of first eliminating bacterial infections, treating the most common ailments, and then doing more investigation, “this idea is the very first blood test that can tell you whether or not the patient has had an infection, and what group of infection it is, down to the individual pathogens. “
Purvesh Khatri, associate professor at the Stanford Institute for Immunity, Transplantation and Infection and Department of Medicine, says our immune systems have been evolving for millennia to fight pathogens, so it may be more effective and efficient to examine the response of our bodies.
“Until now, we haven’t had technology that can measure a set of genes quickly at the point of care,” he said. “But over the past two years there has been enough technology available that now allows us to measure a few genes in a rapid and multiplex fashion at the point of care.”
Although neither the FDA nor any European regulator has approved these kinds of gene-based pathogen detection systems, Khatri, who is helping to launch a related business venture, says they will arrive soon. “Within a year or two, there will be several that will be available on the market.”