With FDA clearance already approved, hospital infection control teams and their clinical laboratories may have another diagnostic tool for diagnosing blood infections
Controlling sepsis in hospitals continues to be a major concern in nations around the world, including in the United States. Now, a new 10-minute clinical laboratory blood test that uses artificial intelligence (AI) and digital images to spot biomarkers of the potentially fatal condition may soon be available for use in hospitals. The test, which was approved to be marketed in the US in 2022 by the federal Food and Drug Administration (FDA), may be “one of the most important breakthroughs in modern medical history,” according to US researchers, Good News Network (GNN) reported.
“Early detection of sepsis is an invaluable capability for healthcare professionals. Quickly identifying sepsis is critical to saving lives, but until now, we’ve lacked a reliable tool to either recognize the condition or explore alternate diagnoses,” said O’Neal in an LSU press release.
“IntelliSep is truly a game changer,” said Hollis O’Neal, MD (above), Associate Professor of Medicine at Louisiana State University Health Sciences Center in Baton Rouge. “The test provides hospital staff with information needed to identify and treat septic patients efficiently and reduce the financial and health burdens of overtreatment for hospitals and patients.” Clinical laboratories may have a new blood test for sepsis by the end of the year. (Photo copyright: Louisiana State University.)
How IntelliSep Works
The IntelliSep test analyzes blood samples extracted from emergency room patients who present with sepsis symptoms by squeezing white blood cells through a tiny tube to determine how the cells react and if they change shape. White blood cells in patients with sepsis are softer and spongier and their shape compresses and elongates, increasing the likelihood of developing sepsis.
Images are taken of the cells using an ultra-high-speed camera that can capture up to 500,000 frames per second. The images are the analyzed by an AI-powered computer which calculates the total number of elongated white blood cells to determine if sepsis is present.
IntelliSep then separates patients into three bands of risk for developing sepsis:
Band 1 (low)
Band 2 (medium)
Band 3 (high)
Results of the test are available to emergency room personnel in less than 10 minutes.
“Sepsis is notorious as the ‘silent killer’ because it is so easily missed early on, when a patient’s symptoms can often be mistaken for other less serious illnesses,” Michael Atar, PhD, DDS, Associate Professor, Pediatric Dentistry at New York University told Good News Network. “Rapid diagnosis and treatment is crucial to a good outcome, but there has never been a single, reliable diagnostic test available to doctors, costing precious time and people’s lives.”
Atar is a lead medical technology investor and an advisor to Cytovale.
‘Holy Grail’ of Sepsis Diagnosis
To complete the IntelliSep study, researchers enrolled 1,002 ER patients who presented with signs of sepsis. IntelliSep correctly identified patients who did not have sepsis with an accuracy rate of 97.5%. The technology showed an accuracy rate of 55% for positive sepsis results. Researchers also used IntelliSep to quickly diagnose and assess the severity of a sepsis infection.
There were no sepsis deaths reported in patients with low-risk scores. This indicates the test could help physicians rule out sepsis and seek other diagnoses for those patients.
“Cytovale’s IntelliSep device is, by any objective measure, the ‘holy grail’ that the medical community has been so desperate to find,” Atar told Good News Network. “The technology behind it is genuinely groundbreaking and it has the real-world, tried-and-tested potential to save millions of lives, year on year, across the planet.”
The technology is currently being used in a few hospitals in Louisiana and the inventors hope to have it available in at least 10 other hospitals by the end of the year.
Our Lady of the Lake Regional Medical Center, a not-for-profit Catholic healthcare ministry located in Baton Rouge, was one of the first hospitals to implement IntelliSep.
“Cytovale’s innovative technology will help drastically decrease the number of sepsis-related deaths in hospital settings, and we are honored that, since day one, we have been a part of the research that led to this technology,” said Chuck Spicer, President of Our Lady of the Lake Health in a news release.
Saint Francis Medical Center in Monroe, La., announced on September 3 that it has started using the IntelliSep test in its emergency rooms and staff are impressed by the impact on hospital efficiency.
“If it turns out negative then you don’t have to treat as many patients as you did before, which runs up costs, hospital bills and causes people to be in the hospital for longer periods of time,” said pulmonary disease physician Thomas Gullatt, MD, President, St. Francis Health, told KNOE News.
Patient Expectations for Treatment
Sepsis, also known as septicemia or blood poisoning, is a serious medical condition that occurs when the body improperly reacts to an infection or injury. The dangerous reaction causes extensive inflammation throughout the body and, if not treated early, can lead to organ failure, tissue damage, and even death.
The Centers for Disease Control and Prevention (CDC) reports at least 1.7 million adults develop sepsis annually in the US and at least 350,000 die as a result of the condition. It also states sepsis is one of the main reasons people are readmitted to hospitals.
Clinical laboratories should be aware of developments in the use of this new diagnostic assay and how it is aiding the diagnosis, antibiotic selection, and monitoring of patients with this deadly infection. Patients often learn about new technologies and come to their hospital or provider expecting to be treated with these innovations.
Findings may lead to new clinical laboratory biomarkers for predicting risk of developing MS and other autoimmune diseases
Scientists continue to find new clinical laboratory biomarkers to detect—and even predict risk of developing—specific chronic diseases. Now, in a recent study conducted at the University of California San Francisco (UCSF), researchers identified antibodies that develop in about 10% of Multiple Sclerosis (MS) patients’ years before the onset of symptoms. The researchers reported that of those who have these antibodies, 100% develop MS. Thus, this discovery could lead to new blood tests for screening MS patients and new ways to treat it and other autoimmune diseases as well.
The UCSF researchers determined that, “in about 10% [of] cases of multiple sclerosis, the body begins producing a distinctive set of antibodies against its own proteins years before symptoms emerge,” Yahoo Life reported, adding that “when [the patients] are tested at the time of their first disease flare, the antibodies show up in both their blood and cerebrospinal fluid.”
That MS is so challenging to diagnose in the first place makes this discovery even more profound. And knowing that 100% of a subset of MS patients who have these antibodies will develop MS makes the UCSF study findings quite important.
“This could be a useful tool to help triage and diagnose patients with otherwise nonspecific neurological symptoms and prioritize them for closer surveillance and possible treatment,” Colin Zamecnik, PhD, scientist and research fellow at UCSF, told Yahoo Life.
“From the largest cohort of blood samples on Earth, we obtained blood samples from MS patients years before their symptoms began and profiled antibodies against self-autoantibodies that are associated with multiple sclerosis diagnosis,” Colin Zamecnik, PhD (above), scientist and research fellow at UCSF, told Yahoo Life. “We found the first molecular marker of MS that appears up to five years before diagnosis in their blood.” These findings could lead to new clinical laboratory tests that determine risk for developing MS and other autoimmune diseases. (Photo copyright: LinkedIn.)
UCSF Study Details
According to the MS International Foundation Atlas of MS, there are currently about 2.9 million people living with MS worldwide, with about one million of them in the US. The disease is typically diagnosed in individuals 20 to 50 years old, mostly targeting those of Northern European descent, Yahoo Life reported.
To complete their study, the UCSF scientists used the Department of Defense Serum Repository (DoDSR), which is comprised of more than 10 million individuals, the researchers noted in their Nature Medicine paper.
From that group, the scientists identified 250 individuals who developed MS, spanning a period of five years prior to showing symptoms through one year after their symptoms first appeared, Medical News Today reported. These people were compared to 250 other individuals in the DoDSR who have no MS diagnosis but who all had similar serum collection dates, ages, race and ethnicities, and sex.
“The researchers validated the serum results against serum and cerebrospinal fluid results from an incident MS cohort at the University of California, San Francisco (ORIGINS) that enrolled patients at clinical onset. They used data from 103 patients from the UCSF ORIGINS study,” according to Medical News Today. “They carried out molecular profiling of autoantibodies and neuronal damage in samples from the 500 participants, measuring serum neurofilament light chain measurement (sNfL) to detect damage to nerve cells.
“The researchers tested the antibody patterns of both MS and control participants using whole-human proteomeseroreactivity which can detect autoimmune reactions in the serum and CSF,” Medical News Today noted.
Many who developed MS had an immunogenicity cluster (IC) of antibodies that “remained stable over time” and was not found in the control samples. The higher levels of sNfL in those with MS were discovered years prior to the first flare up, “indicating that damage to nerve cells begins a long time before symptom onset,” Medical News Today added.
“This signature is a starting point for further immunological characterization of this MS patient subset and may be clinically useful as an antigen-specific biomarker for high-risk patients with clinically or radiologically isolated neuroinflammatory syndromes,” the UCSF scientists wrote in Nature Medicine.
“We believe it’s possible that these patients are exhibiting cross reactive response to a prior infection, which agrees with much current work in the literature around multiple sclerosis disease progression,” Zamecnik told Yahoo Life.
It “validates and adds to prior evidence of neuro-axonal injury occurring in patients during the MS preclinical phase,” the researchers told Medical News Today.
Implications of UCSF’s Study
UCSF’s discovery is a prime example of technology that could soon work its way into clinical use once additional studies and research are done to support the findings.
The researchers believe their research could lead to a simple blood test for detecting MS years in advance and discussed how this could “give birth to new treatments and disease management opportunities,” Neuroscience News reported.
Current MS diagnosis requires a battery of tests, such as lumbar punctures for testing cerebrospinal fluid, magnetic resonance imaging (MRI) scans of the spinal cord and brain, and “tests to measure speed and accuracy of nervous system responses,” Medical News Today noted.
“Given its specificity for MS both before and after diagnosis, an autoantibody serology test against the MS1c peptides could be implemented in a surveillance setting for patients with high probability of developing MS, or crucially at a first clinically isolated neurologic episode,” the UCSF researchers told Medical News Today.
The UCSF discovery is another example of nascent technology that could work its way into clinical use after more research and studies. Microbiologists, clinical laboratories, and physicians tasked with diagnosing MS and other autoimmune diseases should find the novel biomarkers the researchers identified most interesting, as well as what changed with science and technology that enabled researchers to identify these biomarkers for development.
Scientists reported positive Phase 1 trial results of their “intratumoral microdevice” in patients with glioma tumors
Here is an example of new microtechnology which has the potential to greatly shorten the time and improve the ability of physicians to determine which anti-cancer drug is most effective for an individual patient’s glioblastoma. As it is further developed, this technology could give anatomic pathologists and clinical laboratories an increased role in assessing the data produced by microdevices and helping physicians determine the most appropriate anti-cancer drug for specific patients.
In a news release, researchers at Brigham and Women’s Hospital (BWH) in Boston said they have developed an implantable “intratumoral microdevice” (IMD) that functions as a “lab in a patient,” capable of gauging the effectiveness of multiple drugs that target brain tumors. In a Phase 1 clinical trial, they tested the IMD on six patients with glioma tumors.
“In order to make the greatest impact on how we treat these tumors, we need to be able to understand, early on, which drug works best for any given patient,” study co-author Pier Paolo Peruzzi, MD, PhD, told the Harvard Gazette. “The problem is that the tools that are currently available to answer this question are just not good enough. So, we came up with the idea of making each patient their own lab, by using a device which can directly interrogate the living tumor and give us the information that we need.”
Peruzzi is Principal Investigator at the Harvey Cushing Neuro-Oncology Laboratories and Assistant Professor of Neurosurgery at Harvard Medical School.
“Our goal is for the placement of these devices to become an integral part of tumor surgery,” said Pier Paolo Peruzzi, MD PhD (above) of Brigham and Women’s Hospital and Harvard Medical School in an article he co-wrote for Healio. “Then, with the data that we have from these microdevices, we can choose the best systemic chemotherapy to give to that patient.” Pathologists and clinical laboratories may soon play a role in helping doctors interpret data gathered by implantable microdevices and choose the best therapies for their patients. (Photo copyright: Dana-Farber Cancer Institute.)
New Perspective on Tumor Treatments
In a news story he co-wrote for Healio, Peruzzi explained that the microdevice—about the size and shape of a grain of rice—contains up to 30 tiny reservoirs that the researchers fill with the drugs they want to test. Surgeons implant the device during a procedure to remove the tumors.
The surgery takes two to three hours to perform, and during that time, the device releases “nanodoses” of the drugs into confined areas of the tumor. Near the end of the procedure, the device is removed along with tissue specimens. The researchers can then analyze the tissue to determine the effectiveness of each drug.
“This is not in the lab, and not in a petri dish,” Peruzzi told Harvard Gazette. “It’s actually in real patients in real time, which gives us a whole new perspective on how these tumors respond to treatment.”
The Healio story notes that gliomas are “among the deadliest brain cancers and are notoriously difficult to treat.” With current approaches, testing different therapies has posed a challenge, Peruzzi wrote.
“Right now, the only way these drugs are tested in patients is through what are called window-of-opportunity studies, where we give one drug to the patient before we resect the tumor and analyze the effect of the drug,” he said. “We can only do this with one drug at a time.”
Determining Safety of Procedure
The primary goal of the Phase 1 trial was to determine the safety of the procedure, Peruzzi noted. “To be in compliance with standard clinical practice and minimize risks to the patients, we needed to integrate the placement and retrieval of the device during an otherwise standard operation.”
The trial consisted of three men and three women ranging from 27 to 86 years old, with a median age of 76. Five were diagnosed with glioblastoma and one with grade 4 astrocytoma.
“None of the six enrolled patients experienced adverse events related to the IMD, and the exposed tissue was usable for downstream analysis for 11 out of 12 retrieved specimens,” the researchers wrote in Science Translational Medicine. They noted that application of the IMD added about 32 minutes to the time required for the surgery, equating to a cost increase of $7,800.
One drug they tested was temozolomide (TMZ), “the most widely used agent in this patient population,” they wrote. “Several patients in our trial received it systemically, either before or after IMD insertion, as part of the standard of care. Thus, although our trial was not designed to choose chemotherapy agents based on IMD data, we still could compare the observed clinical-radiological response to systemic TMZ with the patient-specific response to TMZ in the IMD-exposed tissue.”
One patient, the researchers noted, had not benefited from the drug “in concordance with the poor tissue response observed in the IMD analysis.” But in another patient, a 72-year-old woman, “IMD analysis showed a marked response to TMZ,” and she survived for 20 months after receiving the treatment “with radiological evidence of tumor response. This was despite having a subtotal tumor resection, in itself an unfavorable prognostic factor. The patient expired because of an unrelated cardiovascular event, although she had remained neurologically stable.”
Drug Duration Limitation
One limitation of the study was that testing the device during the tumor removal procedure limited the duration of the drug treatments, Peruzzi said. The Harvard Gazette noted that following their initial study, the researchers were testing a variation of the procedure in which the device is implanted three days before the main surgery in a minimally invasive technique. This gives the drugs more time to work.
Cancer researchers have theorized that common treatments for tumors can impair the immune system, Peruzzi wrote in Healio. “One thing we want to look at is which drugs can kill the tumor without killing the immune system as well,” he noted.
Future studies will determine the effectiveness of implanting microdevices into tumors to test therapies in vivo. Should they become viable, clinical laboratories and anatomic pathologists will likely be involved in receiving, interpreting, storing, and transmitting the data gathered by these devices to the patient’s doctors.
Discovery highlights how ongoing microbiome research points to new opportunities that can lead to development of more effective cancer screening clinical laboratory tests
New research from the Fred Hutchinson Cancer Center in Seattle once again demonstrates that the human microbiome plays a sophisticated role in many biological processes. Microbiologists and anatomic pathologists who diagnose tissue/biopsies will find this study’s findings intriguing.
This breakthrough in colon cancer research came from the discovery that a “subspecies” of a common type of a bacteria that resides in the mouth and causes dental plaque also “shields tumor cells from cancer treatment,” according to NBC News.
The scientists inspected colorectal cancer (CRC) tumors and found that 50% of those examined featured a subspecies of Fusobacterium nucleatum (F. nucleatum or Fn) and that this anaerobic bacterium was “shielding tumor cells from cancer-fighting drugs,” NBC News noted. Many of these tumors were considered aggressive cases of cancer.
“The discovery, experts say, could pave the way for new treatments and possibly new methods of screening,” NBC News reported.
“Patients who have high levels of this bacteria in their colorectal tumors have a far worse prognosis,” Susan Bullman, PhD (above), who jointly supervised the Fred Hutch research team and who is now Associate Professor of Immunology at MD Anderson Cancer Center, told NBC News. “They don’t respond as well to chemotherapy, and they have an increased risk of recurrence,” she added. Microbiologists and clinical laboratories working with oncologists on cancer treatments will want to follow this research as it may lead to new methods for screening cancer patients. (Photo copyright: Fred Hutchinson Cancer Center.)
Developing Effective Treatments
Susan Bullman, PhD, Associate Professor of Immunology at MD Anderson Cancer Center, who along with her husband and fellow researcher Christopher D. Johnston, PhD, Assistant Professor at Fred Hutchinson Cancer Center, jointly supervised an international team of scientists that examined the genomes of 80 F. nucleatum strains from the mouths of cancer-free patients and 55 strains from tumors in patients with colorectal cancer, according to the National Institutes of Health (NIH). The NIH funded the research.
The researchers targeted a subspecies of F. nucleatum called F. nucleatum animalis (Fna) that “was more likely to be present in colorectal tumors. Further analyses revealed that there were two distinct types of Fna. Both were present in mouths, but only one type, called Fna C2, was associated with colorectal cancer” the NIH wrote in an article on its website titled, “Gum Disease-related Bacteria Tied to Colorectal Cancer.”
“Tumor-isolated strains predominantly belong to Fn subspecies animalis (Fna). However, genomic analyses reveal that Fna, considered a single subspecies, is instead composed of two distinct clades (Fna C1 and Fna C2). Of these, only Fna C2 dominates the CRC tumor niche,” the Fred Hutch researchers wrote in their Nature paper.
“We have pinpointed the exact bacterial lineage that is associated with colorectal cancer, and that knowledge is critical for developing effective preventive and treatment methods,” Johnston told the NIH.
How Bacteria Got from Mouth to Colon Not Fully Understood
Traditionally, F. nucleatum makes its home in the mouth in minute quantities. Thus, it is not fully understood how these bacteria travel from the mouth to the colon. However, the Fred Hutch researchers showed that Fna C2 could survive in acidic conditions, like those found in the gut, longer than the other types of Fna. This suggests that the bacteria may travel along a direct route through the digestive tract.
The study, which focused on participants over 50, comes at a time when colorectal cancer rates are trending upward. Rates are doubling for those under 55, jumping from 11% in 1995 to 20% in 2019. CRC is the second-leading cancer death and over 53,000 will succumb to the disease in 2024, according to NBC News.
Many of the newer diagnoses are in later stages with no clear reason why, and the Fred Hutch scientists are trying to understand how their findings tie into the increase of younger cases of colon cancer.
Bullman says it will be important to look at “whether there are elevated levels of this bacterium in young onset colorectal cancer, which is on the rise globally for unknown reasons,” she told NBC News.
Possibility of More Effective Cancer Screening
There is hope that scientists equipped with this knowledge can develop new and more effective screening and treatment options for colon cancer, as well as studying the microbiome’s impact on other diseases.
On the prevention side, researchers have seen that in mice the addition of Fna “appeared to cause precancerous polyps to form, one of the first warning signs of colorectal cancer, though Bullman added that this causation hasn’t yet been proven in humans.” NBC reported.
Future research may find that screening for Fna could determine if colorectal tumors will be aggressive, NIH reported.
“It’s possible that scientists could identify the subspecies while it’s still in the mouth and give a person antibiotics at that point, wiping it out before it could travel to the colon,” Bullman told NBC News. “Even if antibiotics can’t successfully eliminate the bacteria from the mouth, its presence there could serve as an indication that someone is at higher risk for aggressive colon cancer.”
There is also the thought of developing antibiotics to target a specific subtype of bacteria. Doing so would eliminate the need to be “wiping out both forms of the bacteria or all of the bacteria in the mouth. Further, it’s relevant to consider the possibility of harnessing the bacteria to do the cancer-fighting work,” NBC noted.
“The subtype has already proven that it can enter cancer cells quite easily, so it might be possible to genetically modify the bacteria to carry cancer-fighting drugs directly into the tumors,” Bullman told NBC News.
Further studies and research are needed. However, the Fred Hutch researchers’ findings highlight the sophistication of the human microbiome and hint at the potential role it can play in the diagnosis of cancer by clinical laboratories and pathology groups, along with better cancer treatments in the future.
Scientists turned to metabolomics to find cause of biological aging and release index of 25 metabolites that predict healthy and rapid agers
Researchers at the University of Pittsburg Medical Center and the University of Pittsburgh School of Medicine have identified biomarkers in human blood which appear to affect biological aging (aka, senescence). Since biological aging is connected to a person’s overall condition, further research and studies confirming UPMC’s findings will likely lead to a new panel of tests clinical laboratories can run to support physicians’ assessment of their patients’ health.
UPMC’s research “points to pathways and compounds that may underlie biological age, shedding light on why people age differently and suggesting novel targets for interventions that could slow aging and promote health span, the length of time a person is healthy,” according to a UPMC news release.
“We decided to look at metabolites because they’re very dynamic,” Aditi Gurkar, PhD, the study’s senior author, told the Pittsburgh Post-Gazette. Gurkar is Assistant Professor of Medicine, Division of Geriatric Medicine, Aging Institute at the University of Pittsburg. “They can change because of the diet, they can change because of exercise, they can change because of lifestyle changes like smoking,” she added.
The scientists identified 25 metabolites that “showed clear differences” in the metabolomes of both healthy and rapid agers. Based on those findings, the researchers developed the Healthy Aging Metabolic (HAM) Index, a panel of metabolites that predicted healthy agers regardless of gender or race.
“Age is more than just a number,” said Aditi Gurkar, PhD (above), Assistant Professor of Geriatric Medicine at University of Pittsburg School of Medicine and the study’s senior author in a news release. “Imagine two people aged 65: One rides a bike to work and goes skiing on the weekends and the other can’t climb a flight of stairs. They have the same chronological age, but very different biological ages. Why do these two people age differently? This question drives my research.” Gurkar’s research may one day lead to new clinical laboratory tests physicians will order when evaluating their patients’ health. (Photo copyright: University of Pittsburg.)
Clear Differences in Metabolites
According to the National Cancer Institute, a metabolite is a “substance made or used when the body breaks down food, drugs, or chemicals, or its own tissue (for example, fat or muscle tissue). This process, called metabolism, makes energy and the materials needed for growth, reproduction, and maintaining health. It also helps get rid of toxic substances.”
The UPMC researchers used metabolomics—the study of chemical process in the body that involves metabolites, other processes, and biproducts of cell metabolism—to create a “molecular fingerprint” of blood drawn from individuals in two separate study groups.
They included:
People over age 75 able to walk a flight of stairs or walk for 15 minutes without a break, and
People, age 65 to 75, who needed to rest during stair climbing and walk challenges.
The researchers found “clear differences” in the metabolomes of healthy agers as compared to rapid agers, suggesting that “metabolites in the blood could reflect biological age,” according to the UPMC news release.
“Other studies have looked at genetics to measure biological aging, but genes are very static. The genes you’re born with are the genes you die with,” said Gurkar in the news release.
Past studies on aging have explored other markers of biological age such as low grade-inflammation, muscle mass, and physical strength. But those markers fell short in “representing complexity of biological aging,” the UPMC study authors wrote in Aging Cell.
“One potential advantage of metabolomics over other ‘omic’ approaches is that metabolites are the final downstream products, and changes are closely related to the immediate (path) physiologic state of an individual,” they added.
The researchers used an artificial intelligence (AI) model that could identify “potential drivers of biological traits” and found three metabolites “that were most likely to promote healthy aging or drive rapid aging. In future research, they plan to delve into how these metabolites, and the molecular pathways that produce them, contribute to biological aging and explore interventions that could slow this process,” the new release noted.
“While it’s great that we can predict biological aging in older adults, what would be even more exciting is a blood test that, for example, can tell someone who’s 35 that they have a biological age more like a 45-year-old,” Gurkar said. “That person could then think about changing aspects of their lifestyle early—whether that’s improving their sleep, diet or exercise regime—to hopefully reverse their biological age.”
Looking Ahead
The UPMC scientists plan more studies to explore metabolites that promote healthy aging and rapid aging, and interventions to slow disease progression.
It’s possible that the blood-based HAM Index may one day become a diagnostic tool physicians and clinical laboratories use to aid monitoring of chronic diseases. As a commonly ordered blood test, it could help people find out biological age and make necessary lifestyle changes to improve their health and longevity.
With the incidence of chronic disease a major problem in the US and other developed countries, a useful diagnostic and monitoring tool like HAM could become a commonly ordered diagnostic procedure. In turn, that would allow clinical laboratories to track the same patient over many years, with the ability to use multi-year lab test data to flag patients whose biomarkers are changing in the wrong direction—thus enabling physicians to be proactive in treating their patients.
Ten year collaboration between Google and Harvard may lead to a deeper understanding of the brain and new clinical laboratory diagnostics
With all our anatomic pathology and clinical laboratory science, we still do not know that much about the structure of the brain. But now, scientists at Harvard University and Google Research studying the emerging field of connectomics have published a highly detailed 3D reconstruction of human brain tissue that allows visualization of neurons and their connections at unprecedented nanoscale resolutions.
Further investigation of the nano-connections within the human brain could lead to novel insights about the role specific proteins and molecules play in the function of the brain. Though it will likely be years down the road, data derived from this study could be used to develop new clinical laboratory diagnostic tests.
The data to generate the model came from Google’s use of artificial intelligence (AI) algorithms to color-code Harvard’s electron microscope imaging of a cubic millimeter of neural tissue—equivalent to a half-grain of rice—that was surgically removed from an epilepsy patient.
“That tiny square contains 57,000 cells, 230 millimeters of blood vessels, and 150 million synapses, all amounting to 1,400 terabytes of data,” according to the Harvard Gazette, which described the project as “the largest-ever dataset of human neural connections.”
“A terabyte is, for most people, gigantic, yet a fragment of a human brain—just a minuscule, teeny-weeny little bit of human brain—is still thousands of terabytes,” said neuroscientist Jeff W. Lichtman, MD, PhD, Jeremy R. Knowles Professor of Molecular and Cellular Biology, whose Lichtman Lab at Harvard University collaborated on the project with researchers from Google. The two labs have been working together for nearly 10 years on this project, the Harvard Gazette reported.
Lichtman’s lab focuses on the emerging field of connectomics, defined “as understanding how individual neurons are connected to one another to form functional networks,” said neurobiologist Wei-Chung Allen Lee, PhD, Assistant Professor of Neurology, Harvard Medical School, in an interview with Harvard Medical News. “The goal is to create connectomes—or detailed structural maps of connectivity—where we can see every neuron and every connection.” Lee was not involved with the Harvard/Google Research study.
“The human brain uses no more power than a dim incandescent light bulb, yet it can accomplish feats still not possible with the largest artificial computing systems,” wrote Google Research scientist Viren Jain, PhD (above), in a blog post. “To understand how requires a level of understanding more profound than knowing what part of the brain is responsible for what function. The field of connectomics aims to achieve this by precisely mapping how each cell is connected to others.” Google’s 10-year collaboration with Harvard University may lead to new clinical laboratory diagnostics. (Photo copyright: Google Research.)
Study Data and Tools Freely Available
Along with the Science paper, the researchers publicly released the data along with analytic and visualization tools. The study noted that the dataset “is large and incompletely scrutinized,” so the scientists are inviting other researchers to assist in improving the model.
“The ability for other researchers to proofread and refine this human brain connectome is one of many ways that we see the release of this paper and the associated tools as not only the culmination of 10 years of work, but the beginning of something new,” wrote Google Research scientist Viren Jain, PhD, in a blog post that included links to the online resources.
One of those tools—Neuroglancer—allows any user with a web browser to view 3D models of neurons, axons, synapses, dendrites, blood vessels, and other objects. Users can rotate the models in xyz dimensions.
Users with the requisite knowledge and skills can proofread and correct the models by signing up for a CAVE (Connectome Annotation Versioning Engine) account.
Researchers Found Several Surprises
To perform their study, Lichtman’s team cut the neural tissue into 5,000 slices, each approximately 30 nanometers thick, Jain explained in the blog post. They then used a multibeam scanning electron microscope to capture high-resolution images, a process that took 326 days.
Jain’s team at Google used AI tools to build the model. They “stitched and aligned the image data, reconstructed the three dimensional structure of each cell, including its axons and dendrites, identified synaptic connections, and classified cell types,” he explained.
Jain pointed to “several surprises” that the reconstruction revealed. For example, he noted that “96.5% of contacts between axons and their target cells have just one synapse.” However, he added, “we found a class of rare but extremely powerful synaptic connections in which a pair of neurons may be connected by more than 50 individual synapses.”
In their Science paper, the researchers suggest that “these powerful connections are not the result of chance, but rather that these pairs had a reason to be more strongly connected than is typical,” Jain wrote in the blog post. “Further study of these connections could reveal their functional role in the brain.”
Mysterious Structures
Another anomaly was the presence of “axon whorls,” as Jain described them, “beautiful but mysterious structures in which an axon wraps itself into complicated knots.”
Because the sample came from an epilepsy patient, Jain noted that the whorls could be connected to the disease or therapies or could be found in all brains.
“Given the scale and complexity of the dataset, we expect that there are many other novel structures and characteristics yet to be discovered,” he wrote. “These findings are the tip of the iceberg of what we expect connectomics will tell us about human brains.”
The researchers have a larger goal to create a comprehensive high-resolution map of a mouse’s brain, Harvard Medical News noted. This would contain approximately 1,000 times the data found in the 1-cubic-millimeter human sample.
Dark Daily has been tracking the different fields of “omics” for years, as research teams announce new findings and coin new areas of science and medicine to which “omics” is appended. Connectomics fits that description.
Though the Harvard/Google research is not likely to lead to diagnostic assays or clinical laboratory tests any time soon, it is an example of how advances in technologies are enabling researchers to investigate smaller and smaller elements within the human body.
