Best of all, the researchers say the test could provide an inexpensive means of early diagnosis. This assay could also be used to monitor how well patients respond to cancer therapy, according to a news release.
The protein had previously been identified as a promising biomarker and is readily detectable in tumor tissue, they wrote. However, it is found in extremely low concentrations in blood plasma and is “well below detection limits of conventional clinical laboratory methods,” they noted.
To overcome that obstacle, they employed an ultra-sensitive immunoassay known as a Simoa (Single-Molecule Array), an immunoassay platform for measuring fluid biomarkers.
“We were shocked by how well this test worked in detecting the biomarker’s expression across cancer types,” said lead study author gastroenterologist Martin Taylor, MD, PhD, Instructor in Pathology, Massachusetts General Hospital and Harvard Medical School, in the press release. “It’s created more questions for us to explore and sparked interest among collaborators across many institutions.”
“We’ve known since the 1980s that transposable elements were active in some cancers, and nearly 10 years ago we reported that ORF1p was a pervasive cancer biomarker, but, until now, we haven’t had the ability to detect it in blood tests,” said pathologist and study co-author Kathleen Burns, MD, PhD (above), Chair of the Department of Pathology at Dana-Farber Cancer Institute and a Professor of Pathology at Harvard Medical School, in a press release. “Having a technology capable of detecting ORF1p in blood opens so many possibilities for clinical applications.” Clinical laboratories may soon have a new blood test to detect multiple types of cancer. (Photo copyright: Dana-Farber Cancer Institute.)
Simoa’s Advantages
In their press release, the researchers described ORF1p as “a hallmark of many cancers, particularly p53-deficient epithelial cancers,” a category that includes lung, breast, prostate, uterine, pancreatic, and head and neck cancers in addition to the cancers noted above.
“Pervasive expression of ORF1p in carcinomas, and the lack of expression in normal tissues, makes ORF1p unlike other protein biomarkers which have normal expression levels,” Taylor said in the press release. “This unique biology makes it highly specific.”
Simoa was developed at the laboratory of study co-author David R. Walt, PhD, the Hansjörg Wyss Professor of Bioinspired Engineering at Harvard Medical School, and Professor of Pathology at Harvard Medical School and Brigham and Women’s Hospital.
The Simoa technology “enables 100- to 1,000-fold improvements in sensitivity over conventional enzyme-linked immunosorbent assay (ELISA) techniques, thus opening the window to measuring proteins at concentrations that have never been detected before in various biological fluids such as plasma or saliva,” according to the Walt Lab website.
Simoa assays take less than two hours to run and require less than $3 in consumables. They are “simple to perform, scalable, and have clinical-grade coefficients of variation,” the researchers wrote.
Study Results
Using the first generation of the ORF1p Simoa assay, the researchers tested blood samples of patients with a variety of cancers along with 406 individuals, regarded as healthy, who served as controls. The test proved to be most effective among patients with colorectal and ovarian cancer, finding detectable levels of ORF1p in 58% of former and 71% of the latter. Detectable levels were found in patients with advanced-stage as well as early-stage disease, the researchers wrote in Cancer Discovery.
Among the 406 healthy controls, the test found detectable levels of ORF1p in only five. However, the control with the highest detectable levels, regarded as healthy when donating blood, “was six months later found to have prostate cancer and 19 months later found to have lymphoma,” the researchers wrote.
They later reengineered the Simoa assay to increase its sensitivity, resulting in improved detection of the protein in blood samples from patients with colorectal, gastroesophageal, ovarian, uterine, and breast cancers.
The researchers also employed the test on samples from 19 patients with gastroesophageal cancer to gauge its utility for monitoring therapeutic response. Although this was a small sample, they found that among 13 patients who had responded to therapy, “circulating ORF1p dropped to undetectable levels at follow-up sampling.”
“More Work to Be Done”
The Simoa assay has limitations, the researchers acknowledged. It doesn’t identify the location of cancers, and it “isn’t successful in identifying all cancers and their subtypes,” the press release stated, adding that the test will likely be used in conjunction with other early-detection approaches. The researchers also said they want to gauge the test’s accuracy in larger cohorts.
“The test is very specific, but it doesn’t tell us enough information to be used in a vacuum,” Walt said in the news release. “It’s exciting to see the early success of this ultrasensitive assessment tool, but there is more work to be done.”
More studies will be needed to valid these findings. That this promising new multi-cancer immunoassay is based on a clinical laboratory blood sample means its less invasive and less painful for patients. It’s a good example of an assay that takes a proteomic approach looking for protein cancer biomarkers rather than the genetic approach looking for molecular DNA/RNA biomarkers of cancer.
Japanese scientists who developed the detection method hope to use it to create ‘easy testing kits that anyone can use’
What do ostriches and humans have in common during the current COVID-19 pandemic? The unexpected answer is that ostrich antibodies can be used to identify humans infected with COVID-19. If proven viable in healthcare settings, the possibility exists that new clinical laboratory tests could be developed based on wearable diagnostics technologies that pathologists would interpret for doctors and patients.
According to Study Finds, scientists at Kyoto Prefectural University in Japan have created a removable mask filter that, when sprayed with a fluorescent dye coated with antibodies extracted from ostrich eggs, will glow under UV light when COVID-19 is detected. The discovery by Yasuhiro Tsukamoto, PhD (above), President of Kyoto Prefectural University, and his researchers could lead to development of low-cost at home COVID-19 testing kits using the same ostrich-antibody-based technique. (Photo copyright: Kyoto Prefectural University/Reuters.)
The KPU scientists conducted a small study with 32 COVID-19 patients over a 10-day span. The surgical-style masks they wore later glowed around the nose and mouth areas but became dimmer over time as their viral load decreased.
“The ostrich antibody for corona placed on the mouth filter of the mask captures the coronavirus in coughing, sneezing, and water,” the researchers explained in Study Finds.
Tsukamoto himself learned he had contracted COVID-19 after wearing a prototype mask and noticing it glowed under UV light. A PCR test later confirmed his diagnosis, Kyodo News reported.
The KPU team “hopes to further develop the masks so they will glow automatically, without special lighting, if the [COVID-19] virus is detected.” Reuters noted in its coverage of the ostrich-antibody masks.
Making Medicine from Ostrich Antibodies
A profile in Audubon noted that Tsukamoto, who also serves as a veterinary medicine professor at Kyoto Prefectural University, made ostriches the focus of his research since the 1990s as he looked for ways to harness the dinosaur-like bird’s properties to fight human infections. He maintains a flock of 500 captive ostriches. Each female ostrich can produce 50 to 100 eggs/year over a 50-year life span.
Tsukamoto’s research focuses on customizing the antibodies in ostrich eggs by injecting females with inactive viruses, allergens, and bacteria, and then extracting the antibodies to develop medicines for humans. Antibodies form in the egg yolks in about six weeks and can be collected without harming the parent or young.
“The idea of using ostrich antibodies for therapeutics in general is a very interesting concept, particularly because of the advantages of producing the antibodies from eggs,” Ashley St. John, PhD, an Associate Professor in Immunology, at Duke-NUS Medical School in Singapore, told Audubon.
While more clinical studies will be needed before ostrich-antibody masks reach the commercial marketplace, Tsukamoto’s team is planning to expand their experiment to 150 participants with a goal of receiving Japanese government approval to begin selling the glowing COVID-detection masks as early as 2022. But they believe the ostrich-antibody technique ultimately may lead to development of an inexpensive COVID-19 testing kit.
“We can mass-produce antibodies from ostriches at a low cost. In the future, I want to make this into an easy testing kit that anyone can use,” Tsukamoto told Kyodo News.
Harvard, MIT Also Working on COVID-19 Detecting Facemask
According to Fast Company, the MIT/Harvard COVID-19-detecting masks use the same core technology as previous paper tests for Ebola and Zika that utilize proteins and nucleic acids embedded in paper that react to target molecules.
Fast Company explained that the mask wearer launches a test by pushing a button to release a small water reservoir embedded in the mask (above). Droplets from their breath are than analyzed by the sensors in the masks, which could be adapted to test for new COVID variants or other respiratory pathogens. In addition to eliminating the use of a nasal swab, the mask-based testing system may compete with clinical laboratory-based results. (Photo copyright: Felice Frankel/MIT.)
“They would especially be useful in situations where local variant outbreaks are occurring, allowing people to conveniently test themselves at home multiple times a day,” he told Fast Company.
“It’s on par specificity and sensitivity that you will get in a state-of-the-art [medical] laboratory, but with no one there,” Luis Ruben Soenksen, PhD, Venture Builder in Artificial Intelligence and Healthcare at MIT and one of the co-authors of the Nature Biotechnology study, told Fast Company.
As the definition of “wearable diagnostic technology” broadens, pathologists and clinical laboratory scientists may see their roles expand to include helping consumers interpret data collected by point-of-care testing technology as well as performing, evaluating, and interpreting laboratory test results that come from non-traditional sources.
By analyzing ancient poop, researchers have discovered how much the human microbiome has changed over the past millennium, what may have brought about the change, and how those changes formed today’s human microbiome
Two thousand year-old human poop has yielded new insights into the evolution of the microbial cells (microbiota) inhabiting today’s human gut—collectively known as the human microbiome—that could help pathologists and clinical laboratories better understand diseases that may be linked to gut bacteria.
A recent study conducted by an international team of scientists reveals that the gut bacteria of today’s humans may have been altered by the onset of modern processed foods, sanitation, and the use of antibiotics.
In “Reconstruction of Ancient Microbial Genomes from the Human Gut,” published in the journal Nature, the researchers wrote, “In this study, we establish that palaeofaeces [Paleofeces in the US] with well-preserved DNA are abundant sources of microbial genomes, including previously undescribed microbial species, that may elucidate the evolutionary histories of human microbiomes. Similar future studies tapping into the richness of palaeofaeces will not only expand our knowledge of the human microbiome but may also lead to the development of approaches to restore present-day gut microbiomes to their ancestral state.”
Ancient Poop Is a ‘Time Machine’ into the Human Microbiome
To perform the research for this study, scientists analyzed Deoxyribonucleic acid (DNA) from eight preserved, fossilized feces (coprolites) to gain insight into the gut bacteria of ancient communities. The samples used in the research were originally found in rock formations in Utah and Mexico and were preserved by dryness and stable temperatures. The coprolites were between 1,000 and 2,000 years old.
“These paleofeces are the equivalent of a time machine,” Justin Sonnenburg, PhD, Associate Professor, Microbiology and Immunology at Stanford University and co-author of the study, told Science. Tiny bits of food found in the coprolites indicated that the diet of the ancient people included:
The dried-out poop samples were first radiocarbon dated. Then, tiny fragments of the coprolites were rehydrated which allowed researchers to recover longer DNA strands than those found in previous, similar studies. This study compared the microbiome of the ancient populations to that of present-day individuals. The authors of the study suggest that during the past millennium, the human microbiome has lost dozens of bacterial species and has become less diverse.
Other research studies have linked lower diversity among gut bacteria to higher rates of modern diseases, such as diabetes, obesity, and allergies, Science noted.
“We really wanted to be able to go back in time and see when those changes [in the modern gut microbiome] came about, and what’s causing them,” Archeological Geneticist Christina Warinner, PhD, Assistant Professor of Anthropology at Harvard University and one of the authors of the study, told Science. “Is it food itself? Is it processing, is it antibiotics, is it sanitation?” Warinner is the Sally Starling Seaver Assistant Professor at the Radcliffe Institute, and a group leader in the Department of Archaeogenetics at the Max Planck Institute for Evolutionary Anthropology and affiliated with the faculty of biological sciences at the Friedrich Schiller University in Jena, Germany. (Photo copyright: The Game Changers.)
Ancient versus Modern Microbiome
The ancient microbiomes lacked markers for antibiotic resistance and included dozens of bacterial species that were previously unknown. According to the study, “a total of 181 of the 498 reconstructed microbial genomes were classified as gut derived and had extensive DNA damage, consistent with an ancient origin, and 39% of the ancient genomes offered evidence of being newly discovered species.”
The scientists also discovered that the gut bacteria of present-day people living in non-industrialized societies is more like that of the ancient people when compared to present-day humans living in industrialized societies. But there are still vast differences between the ancient and the modern microbiome.
For example, a bacteria known as Treponema is virtually unknown in the microbiome of current humans, even those living in non-industrialized societies. However, according to Kostic, “They’re present in every single one of the paleofeces, across all the geographic sites. That suggests it’s not purely diet that’s shaping things,” he told Science.
What Can Clinical Laboratories Learn from Ancient Poop?
The ancient poop study scientists hope that future research on coprolites from the past will reveal more information regarding when shifts in the microbiome occurred and what events or human activities prompted those changes.
Research on the human microbiome has been responsible for many discoveries that have greatly impacted clinical pathology and diagnostics development.
Microbiologists and other medical laboratory scientists may soon have more useful biomarkers that aid in earlier, more accurate detection of disease, as well as guiding physicians to select the most effective therapies for specific patients, a key component of Precision Medicine.
The findings of this study are another step forward in understanding the composition and functions of gut bacteria. The study of the microbiome could prove to be a growth area for clinical laboratories and microbiology labs as well. It is probable that soon, labs will be performing more microbiome testing to help with the diagnosis, and treatment selection and monitoring of patients.
Clinical laboratories involved in genetic testing may find this welcomed news, after a pair of studies conducted in 2019 raised concerns about CRISPR base editing. The researchers of those studies observed that it “causes a high number of unpredictable mutations in mouse embryos and rice,” Chemical and Engineering News (C&EN) reported, adding, “Other groups have raised concerns about off-target mutations caused when the traditional CRISPR-Cas9 form of gene editing cuts DNA at a location that it wasn’t supposed to touch. The results of the new studies are surprising, however, because scientists have lauded base editors as one of the most precise forms of gene editing yet.”
Nevertheless, UC Berkeley’s latest breakthrough is expected to drive development of new and more accurate CRISPR-Cas genome-editing tools, which consist of base editors as well as nucleases, transposases, recombinases, and prime editors.
Understanding CRISPR Base Editors At a ‘Deeper Level’
Harvard University Chemistry and Chemical Biology Professor David Liu, PhD, who co-authored the study, explained the significance of this latest discovery.
“While base editors are now widely used to introduce precise changes in organisms ranging from bacteria to plants to primates, no one has previously observed the three-dimensional molecular structure of a base editor,” he said in a UC Berkeley news release. “This collaborative project reveals the beautiful molecular structure of a state-of-the-art highly-active base editor—ABE8e—caught in the act of engaging a target DNA site.”
UC Berkeley Professor Jennifer Doudna, PhD (above), who served as senior author of the study, says scientists may now have the information necessary to refine base editors and improve their precision and genome-targeting ability. “This structure helps us understand base editors at a much deeper level,” she said in the UC Berkeley statement. “Now that we can see what we’re working with, we can develop informed strategies to improve the system.” (Photo copyright: UC Berkeley.)
Jennifer Doudna, PhD, UC Berkeley Professor, Howard Hughes Medical Institute Investigator, and senior author of the study, has been a leading figure in the development of CRISPR-Cas9 gene editing. In 2012, Doudna and Emmanuelle Charpentier, PhD, Founding, Scientific and Managing Director at Max Planck Unit for the Science of Pathogens in Berlin, led a team of researchers who “determined how a bacterial immune system known as CRISPR-Cas9 is able to cut DNA, and then engineered CRISPR-Cas9 to be used as a powerful gene editing technology.” In a 2017 news release, UC Berkeley noted that the work has been described as the “scientific breakthrough of the century.”
Viewing the Base Editor’s 3D Shape
CRISPR-Cas9 gene editing allows scientists to permanently edit the genetic information of any organism, including human cells, and has been used in agriculture as well as medicine. A base editor is a tool that manipulates a gene by binding to DNA and replacing one nucleotide with another.
According to the recent UC Berkeley news release, the research team used a “high-powered imaging technique called cryo-electron microscopy” to reveal the base editor’s 3D shape.
Genetic Engineering and Biotechnology News notes that, “The high-resolution structure is of ABE8e bound to DNA, in which the target adenine is replaced with an analog designed to trap the catalytic conformation. The structure, together with kinetic data comparing ABE8e to earlier ABEs [adenine base editors], explains how ABE8e edits DNA bases and could inform future base-editor design.”
The graphic above, taken from the UC Berkeley news release, shows the “3D structure of a base editor, comprised of the Cas9 protein (white and gray), which binds to a DNA target (teal and blue helix) complementary to the RNA guide (purple), and the deaminase proteins (red and pink), which switch out one nucleotide for another.” (Image and caption copyright: UC Berkeley.)
Knowing the Cas9 fusion protein’s 3D structure may help eliminate unintended off-target effects on RNA, extending beyond the targeted DNA. However, until now, scientists have been hampered by their inability to understand the base editor’s structure.
“If you really want to design truly specific fusion protein, you have to find a way to make the catalytic domain more a part of Cas9, so that it would sense when Cas9 is on the correct target and only then get activated, instead of being active all the time,” study co-first author Audrone Lapinaite, PhD, said in the news release. At the time of the study, Lapinaite was a postdoctoral fellow at UC Berkeley. She is now an assistant professor at Arizona State University.
“As a structural biologist, I really want to look at a molecule and think about ways to rationally improve it. This structure and accompanying biochemistry really give us that power,” added UC Berkeley postdoctoral fellow Gavin Knott, PhD, another study co-author. “We can now make rational predications for how this system will behave in a cell, because we can see it and predict how it’s going to break or predict ways to make it better.”
Clinical laboratory leaders and pathologists will want to monitor these new advances in CRISPR technology. Each breakthrough has the power to fuel development of cost-effective, rapid point-of-care diagnostics.
Report’s authors claim the US needs to be testing 20-million people per day in order to achieve ‘full pandemic resilience’ by August
Medical laboratory scientists and clinical laboratory leaders know that the US’ inability to provide widespread diagnostic testing to detect SARS-CoV-2—the novel coronavirus that causes the COVID-19 illness—in the early stages of the outbreak was a major public health failure. Now a Harvard University report argues the US will need to deliver five million tests per day by early June—more than the total number of people tested nationwide to date—to safely begin reopening the economy.
“We need to deliver five million tests per day by early June to deliver a safe social reopening,” the report’s authors state. “This number will need to increase over time (ideally by late July) to 20 million a day to fully remobilize the economy. We acknowledge that even this number may not be high enough to protect public health. In that considerably less likely eventuality, we will need to scale-up testing much further. By the time we know if we need to do that, we should be in a better position to know how to do it. In any situation, achieving these numbers depends on testing innovation.”
The report is the work of a diverse group of experts in economics, public health, technology, and ethics, from major universities and big technology companies (Apple, Microsoft) with support from The Rockefeller Foundation.
“This is the first plan to show operationally how we can scale up COVID-19 testing sufficiently to safely reopen the economy—while safeguarding fundamental American democratic principles of protecting civil rights and liberties,” Danielle Allen, PhD (above), Director of Harvard University’s Edmond J. Safra Center for Ethics, said in a statement that noted it was “in response to the US Department of Health and Human Service’s Report to Congress on its COVID-19 strategic testing plan.” (Photo copyright: Harvard University.)
Under Harvard’s Roadmap plan, massive-scale testing would involve rapid development of:
Streamlined sample collection (for example) involving saliva samples (spit kits) rather than deep nasal swabs that have to be taken by healthcare workers;
Transportation logistics systems able to rapidly collect and distribute samples for testing;
Mega-testing labs, each able to perform in the range of one million tests per day, with automation, streamlined methods, and tightly managed supply chains;
Information systems to rapidly transmit test results; and
Technology necessary to certify testing status.
“The unique value of this approach is that it will prevent cycles of opening up and shutting down,” Anne-Marie Slaughter, CEO of New America, said in the statement. “It allows us to mobilize and re-open progressively the parts of the economy that have been shut down, protect our frontline workers, and contain the virus to levels where it can be effectively managed and treated until we can find a vaccine.”
Is Expanding Clinical Laboratory Testing Even Possible?
But is such a plan realistic? Perhaps not. When questioned by NBC News about the timeline for “broad-based coronavirus testing” that was suggested as part of the Trump Administration’s three-phase plan to reopen the states, former FDA Commissioner Scott Gottlieb, MD, said, “We’re not going to be there. We’re not going to be there in May, we’re not going to be there in June, hopefully, we’ll be there by September.”
In recent weeks, however, US testing capabilities have improved. Quest Diagnostics, which had come under fire for its testing backlog in California, announced it now has the capacity to perform 50,000 diagnostic COVID-19 tests per day or 350,000 tests per week with less than a two-day turnaround for results. “Our test capacity outpaces demand and we have not experienced a test backlog for about a week,” Quest said in a statement.
CDC ‘Modifies’ Its Guidelines for Declaring a Person ‘Recovered’ from COVID-19
Furthermore, the CDC modified its guidance on the medical and testing criteria that must be met for a person to be considered recovered from COVID-19, which initially required two negative test results before a patient could be declared “confirmed recovered” from the virus. The CDC added a non-testing strategy that allowed states to begin counting “discharged” patients who did not have easy access to additional testing as recovered from the virus.
Under the non-test-based strategy, a person may be considered recovered if:
At least three days (72 hours) have passed since recovery, defined as resolution of fever without the use of fever-reducing medications;
Improvement in respiratory symptoms (e.g., cough, shortness of breath); and,
At least seven days have passed since symptoms first appeared.
For now, however, the focus will likely remain on testing for those who are infected, rather than for finding those who have recovered. As of May 30, the COVID Tracking Project reported that only 16,495,443 million tests had been conducted in the US, with 1,759,693 of those test showing positive for COVID-19. That’s closing in on the 10% “test-positivity rate” recommended by the WHO for controlling a pandemic, but it’s not quite there.
As testing for COVID-19 grows exponentially, clinical laboratories should anticipate playing an increasingly important role in the nation’s response to the COVID-19 pandemic.
