Jul 20, 2018 | Digital Pathology, Instruments & Equipment, Laboratory Instruments & Laboratory Equipment, Laboratory Management and Operations, Laboratory News, Laboratory Operations, Laboratory Pathology, Laboratory Testing
Should greater attention be given to protein damage in chronic diseases such as Alzheimer’s and diabetes? One life scientist says “yes” and suggests changing how test developers view the cause of age-related and degenerative diseases
DNA and the human genome get plenty of media attention and are considered by many to be unlocking the secrets to health and long life. However, as clinical laboratory professionals know, DNA is just one component of the very complex organism that is a human being.
In fact, DNA, RNA, and proteins are all valid biomarkers for medical laboratory tests and, according to one life scientist, all three should get equal attention as to their role in curing disease and keeping people healthy.
Along with proteins and RNA, DNA is actually an “equal partner in the circle of life,” wrote David Grainger, PhD, CEO of Methuselah Health, in a Forbes opinion piece about what he calls the “cult of DNA-centricity” and its relative limitations.
Effects of Protein Damage
“Aging and age-related degenerative diseases are caused by protein damage rather than by DNA damage,” explained Grainger, a Life Scientist who studies the role proteins play in aging and disease. “DNA, like data, cannot by itself do anything. The data on your computer is powerless without apps to interpret it, screens and speakers to communicate it, keyboards and touchscreens to interact with it.”
“Similarly,” he continued, “the DNA sequence information (although it resides in a physical object—the DNA molecule—just as computer data resides on a hard disk) is powerless and ethereal until it is translated into proteins that can perform functions,” he points out.
According to Grainger, diseases such as cystic fibrosis and Duchenne Muscular Dystrophy may be associated with genetic mutation. However, other diseases take a different course and are more likely to develop due to protein damage, which he contends may strengthen in time, causing changes in cells or tissues and, eventually, age-related diseases.
“Alzheimer’s disease, diabetes, or autoimmunity often take decades to develop (even though your genome sequence has been the same since the day you were conceived); the insidious accumulation of the damaged protein may be very slow indeed,” he penned.
“But so strong is the cult of DNA-centricity that most scientists seem unwilling to challenge the fundamental assumption that the cause of late-onset diseases must lie somewhere in the genome,” Grainger concludes.
Shifting Focus from Genetics to Proteins
Besides being CEO of Methuselah Health, Grainger also is Co-Founder and Chief Scientific Advisor at Medicxi, a life sciences investment firm that backed Methuselah Health with $5 million in venture capital funding for research into disease treatments that focus on proteins in aging, reported Fierce CEO.
Methuselah Health, founded in 2015 in Cambridge, UK, with offices in the US, is reportedly using post-translational modifications for analysis of many different proteins.
“At Methuselah Health, we have shifted focus from the genetics—which tells you in an ideal world how your body would function—to the now: this is how your body functions now and this is what is going wrong with it. And that answer lies in the proteins,” stated Dr. David Grainger (above), CEO of Methuselah Health, in an interview with the UK’s New NHS Alliance. Click on this link to watch the full interview. [Photo and caption copyright: New NHS Alliance.]
This is how Methuselah Health analyzes damaged proteins using mass spectrometry, according to David Mosedale, PhD, Methuselah Health’s Chief Technology Officer, in the New NHS Alliance story:
- Protein samples from healthy individuals and people with diseases are used;
- Proteins from the samples are sliced into protein blocks and fed slowly into a mass spectrometer, which accurately weighs them;
- Scientists observe damage to individual blocks of proteins;
- Taking those blocks, proteins are reconstructed to ascertain which proteins have been damaged;
- Information is leveraged for discovery of drugs to target diseases.
Mass spectrometry is a powerful approach to protein sample identification, according to News-Medical.Net. It enables analysis of protein specificity and background contaminants. Interactions among proteins—with RNA or DNA—also are possible with mass spectrometry.
Methuselah Health’s scientists are particularly interested in the damaged proteins that have been around a while, which they call hyper-stable danger variants (HSDVs) and consider to be the foundation for development of age-related diseases, Grainger told WuXi AppTec.
“By applying the Methuselah platform, we can see the HSDVs and so understand which pathways we need to target to prevent disease,” he explained.
For clinical laboratories, pathologists, and their patients, work by Methuselah Health could accelerate the development of personalized medicine treatments for debilitating chronic diseases. Furthermore, it may compel more people to think of DNA as one of several components interacting that make up human bodies and not as the only game in diagnostics.
—Donna Marie Pocius
Related Information:
The Cult of DNA-Centricity
Methuselah Health CEO David Grainger Out to Aid Longevity
VIDEO: Methuselah Health, Addressing Diseases Associated with Aging
Understanding and Slowing the Human Aging Clock Via Protein Stability
Using Mass Spectrometry for Protein Complex Analysis
Jul 18, 2018 | Instruments & Equipment, Laboratory Instruments & Laboratory Equipment, Laboratory News, Laboratory Operations, Laboratory Testing, Management & Operations
MUSE microscope speeds up some anatomic pathology laboratory processes and removes exposure to toxic fixative chemicals
Because they handle tissue specimens, histotechnologists, anatomic pathologists, and hospital nurses are exposed to deadly chemicals such as formaldehyde, formalin, Xylene, and Toluene. The risks associated with these chemicals has been covered regularly by Dark Daily as recently as 2018 and as far back as 2011. (See, “Europe Implements New Anatomic Pathology Guidelines to Reduce Nurse Exposure to Formaldehyde and Other Toxic Histology Chemicals,” January 3, 2018; and, “Health of Pathology Laboratory Technicians at Risk from Common Solvents like Xylene and Toluene,” July 5, 2011.)
Now, scientists at the University of California at Davis (UC Davis) have developed a microscope that uses ultraviolet light (UV) to illuminate tissue samples. The UV microscope removes the need for traditional histology processes involved with preparation of tissue to produce conventional slides and makes it possible for anatomic pathologists to evaluate tissues without formalin fixation, according to a UC Davis news release.
“Here, we introduce a simple, non-destructive slide-free technique that, within minutes, provides high-resolution diagnostic histological images resembling those obtained from conventional hematoxylin and eosin histology,” the researchers wrote in their paper, published in Nature Biomedical Engineering.
High-resolution Biopsy Images in Minutes
The UV microscope relies on technology that UC Davis researchers dubbed MUSE, which stands for Microscopy with Ultraviolet Surface Excitation. According to the researchers, MUSE produces high-resolution images of biopsies and other fresh tissue samples that are ready for a pathologist’s review within minutes.
“MUSE eliminates any need for conventional tissue processing with formalin fixation, paraffin embedding, or thin-sectioning. It doesn’t require lasers, confocal, multiphoton, or optical coherence tomography instrumentation. And the simple technology makes it well-suited for deployment wherever biopsies are obtained and evaluated,” stated Richard Levenson, MD, MUSE Microscopy CEO, Professor, and Vice Chair for Strategic Technologies in the Department of Pathology and Laboratory Medicine at UC Davis, in the news release.
Ultraviolet microscopy is distinguished by its ability to magnify samples and enable views with greater resolution. This is due to the shorter wavelength of ultraviolet light, which improves image resolution beyond the diffraction limit of optical microscopes using normal white light, according to News Medical.
The unique ultraviolet light microscope tool may soon enable clinical laboratories and anatomic pathology groups to accurately report on biopsies to physicians and patients faster, for less money, and without exposure to deadly chemicals. This would be timely considering the pressure on the pathology industry to switch to value-based reimbursement from fee-for-service billing, and to embrace personalized medicine.
“It has become increasingly important to submit relevant portion of often tiny tissue samples for DNA and other molecular functional tests,” notes Richard Levenson, MD, MUSE Microscopy CEO, Professor, and Vice Chair for Strategic Technologies in the Department of Pathology and Laboratory Medicine at UC Davis, shown above with MUSE. “Making sure that the submitted material actually contains tumor in sufficient quantity is not always easy and sometimes just preparing conventional microscope slices can consume most of or even all of small specimens. MUSE is important because it quickly provides images from fresh tissue without exhausting the sample.” (Photo and caption copyright: UC Davis.)
MUSE is being commercialized and investors sought by MUSE Microscopy, Inc.
Traditional Microscopy is Time-Consuming, Hazardous, Expensive
Light microscopy, a time-honored technology, has been available to pathologists for more than 200 years. It is the cornerstone for cancer diagnostics and pathology, the UC Davis researchers acknowledged. But it requires time-consuming and expensive processes, which are especially glaring in a resource-challenged healthcare industry, they pointed out.
“Histological examination of tissues is central to the diagnosis and management of neoplasms and many other diseases. However, commonly used bright-field microscopy requires prior preparation of micrometer-thick tissue sections mounted on glass slides—a process that can require hours or days, contributes to cost, and delays access to critical information,” they wrote in their paper.
“MUSE promises to improve the speed and efficiency of patient care in both state-of-the art and low-resource settings, and to provide opportunities for rapid histology in research,” they continued.
No Histology Slide Preparation Needed
MUSE developers also called attention to the use of hazardous chemicals, such as formalin, in lab processes, which has been linked to cancers including myeloid leukemia, nasopharyngeal cancer, and sinonasal cancer, according to a National Academy of Sciences report. Still, more than 300 million slides are prepared in the US each year at a cost of several billion dollars to the healthcare industry, according to the MUSE Website.
MUSE, however, penetrates tissue samples by using ultraviolet light at short wavelengths—below the 300-nanometer range. The MUSE ultraviolet microscope can reach several microns-deep into tissues.
That’s enough, the researchers claim, to be comparable with the thickness of tissue slices anatomic pathologists use with traditional microscope slides. However, MUSE requires no conventional tissue processing associated with histology slides.
How Does it Work?
MUSE is comprised of an optical system with UV light-emitting diodes (LEDs), a UV compatible stage, and a conventional microscope. That’s according to Photonics Online, which described the process:
- “UV light at 280 nanometer spectral range illuminates about one square millimeter of specimen;
- “Surface is limited to a few nanometers deep to make high-contrast images possible;
- “Excitation light, at sub-300 nanometer spectral region, elicits bright emission from tissue specimens;
- “Specimens, which were stained with conventional florescent dyes, emit photons;
- “Photons are captured using glass-based microscope optics;
- “A Python programing language solution, with a graphics unit, converts MUSE images in real-time;
- “Images are comparable to the hematoxylin and eosin versions histologists and pathologists are accustomed to.”
The result, according the MUSE website, “is stunning detailed images conveying a degree of resolution, structure, and depth unachievable until now by any single technology.”
Other Alternative Histology Processes Under the Microscope
MUSE is not the only approach being studied that could create cellular images without sectioning tissue samples. Anatomic and histopathology laboratory leaders looking to differentiate their labs should keep watch on the development of MUSE and other alternatives to current histology methods, especially once these new devices become green-lighted by the Food and Drug Administration (FDA) for use in patient care.
—Donna Marie Pocius
Related Information:
Microscope That Uses Ultraviolet Instead of Visible Light Emerging as Powerful Diagnostic Tool
Microscope with Ultraviolet Surface Excitation for Rapid Slide-Free Histology
Ultraviolet Microscope to Dramatically Speed-up Lab Tests
What is Ultraviolet Microscopy?
Europe Implements New Anatomic Pathology Guidelines to Reduce Nurse Exposure to Formaldehyde and Other Toxic Histology Chemicals
National Academy of Sciences Confirms That Formaldehyde Can Cause Cancer in a Finding That Has Implications for Anatomic Pathology and Histology Laboratories
Health of Pathology Laboratory Technicians at Risk from Common Solvents like Xylene and Toluene
Jul 13, 2018 | Digital Pathology, Instruments & Equipment, Laboratory Instruments & Laboratory Equipment, Laboratory Management and Operations, Laboratory News, Laboratory Operations, Laboratory Pathology, Management & Operations, News From Dark Daily
Popularity of the pocket-sized gene-sequencing device continues to prove that DNA testing away from clinical laboratories in remote clinics and outlying field laboratories is not just possible, but in some cases preferable
Once again, Oxford Nanopore Technologies (ONT) is demonstrating how next-generation gene sequencing technology can make it cheaper, simpler, and faster to sequence without the need for big clinical laboratories. And its successful raising of $180 million to expand development worldwide shows the support it has with capital funding investors.
Dark Daily has repeatedly reported on the development of the UK-based company’s point-of-care DNA sequencer going back to 2011. Called MinION, we predicted in 2015, that once brought to market, the pocket-sized gene sequencing machine “could help achieve the NIH’s goal of $1,000 human genome sequencing and, in remote clinics and outbreak zones, shift testing away from medical laboratories.” (See Dark Daily, “Point-of-Care DNA Sequencer Inching Closer to Widespread Use as Beta-Testers Praise Oxford Technologies’ Pocketsize, Portable Nanopore Device,” November 4, 2015.)
Since then, MinION’s use worldwide “for a number of biological analysis techniques including de novo sequencing, targeted sequencing, metagenomics, epigenetics, and more” has only expanded, according to multiple sources and ONT’s website.
How Does MinION Work as a Gene Sequencer?
The MinION nanopore sequencing device weighs about 100 grams (less than four ounces), is about the size of a standard deck of cards, operates off a laptop USB plug, and can sequence genetic material in a matter of minutes.
To perform the nanopore sequencing, a strand of deoxyribonucleic acid (DNA) or ribonucleic acid (RNA) is pushed through small pores in a membrane. An ionic current is then applied to the material and voltage is implemented to measure any disruptions in the current. The resulting measurement represents an electrical signal that is converted to human-readable sequence.
“It’s like the ultimate barcode,” Gordon Sanghera, PhD, Chief Executive Officer at Oxford Nanopore, told BBC News.
Oxford Nanopore Technologies’ diminutive MinION gene-sequencing device has the capacity to directly recognize epigenetic markers that control gene activity and cellular processes involved in the onset and development of disease. Early detection of cancers, testing for birth defects and infectious diseases, and blood screening are possible future clinical laboratory applications for the MinION. Click on this link to watch video on MinION. (Photo copyright: Oxford Nanopore Technologies.)
Why is MinION Important?
One advantage to this technology is that it has the ability to sequence much longer strands of DNA when compared to existing technologies. The MinION can sequence over a million letters or bases, around 2% of a DNA strand or chromosome with 96% or above accuracy. The device can read remarkably long stretches of consecutive DNA letters. Readouts of several thousand letters are common and the record for the MinION is 882,000 consecutive DNA letters, Technology Review noted.
“One of the most important findings of this research was that, even though the human genome reference was completed or thought to have been completed a while ago, it still contains many missing pieces and we were able to close some of those gaps in the sequence by developing a new method for developing these extremely long reads using nanopore sequencing,” Nick Loman, PhD, Professor of Microbial Genomics and Bioinformatics at the School of Biosciences at the University of Birmingham, UK, told Pharmaphorum. Loman worked on research with Oxford Nanopore on nanopore sequencing.
“We’ve gone from a situation where you can only do genome sequencing for a huge amount of money in well-equipped labs to one where we can have genome sequencing literally in your pocket just like a mobile phone,” Loman told BBC News. “That gives us a really exciting opportunity to start having genome sequencing as a routine tool, perhaps something people can do in their own home.”
Using MinION in the Field
According to the Oxford Nanopore website, the MinION:
- Is pocket-sized and portable;
- Has up to 512 nanopore channels;
- Has a simple 10-minute sample preparation time;
- Allows real-time analysis for rapid and efficient results; and,
- Is adaptable to direct DNA or RNA sequencing.
The MinION Starter Pack is available for purchase on the company’s website with prices starting at $1,000. The kit includes:
- The MinION device;
- Flow cells;
- Sequencing kits;
- Wash kits; and,
- MinION community support.
Researchers at The Kinghorn Center for Clinical Genomics at the Garvan Institute of Medical Research in Darlinghurst, Australia, are currently using the MinION for research purposes.
Members of the Zebra Project (above), an international group of scientists, used Oxford Nanopore Technologies’ MinION to sequence genomes during epidemics in Latin America. With just a laptop computer for power, MinION can run complex gene-sequencing and achieve superior results than other similar technologies. It is in use worldwide bringing clinical laboratory testing to patients in remote, outlying locations. (Photo copyright: Ricardo Funari.)
“I think it’s really expanding the arsenal of tools we have to peer into cell biology and the root causes of cancer and various diseases,” Dr. Martin Smith, Head of Genomic Technologies at the center, told Australian Financial Review. “It’s really just starting to open the lid off the jar and peer more deeply into the genomics of the cell.”
Dr. Sanghera hopes the gadget could be utilized in the future to identify common infections at home and help consumers avoid unnecessary trips to doctors, clinics, and hospitals, and avert the misuse and overuse of prescription medications. He also feels MinION has applications outside the healthcare industry, such as detecting the presence of harmful microbes in food and water supplies.
As gadgets like MinION become more popular, the potential to move DNA sequencing closer to the patient (and out of the core lab) has implications for clinical laboratories and anatomic pathology groups. However, core labs would still be a preferred source to collect the raw data, store that data, then do the annotation of the DNA sequences and report the findings to the referring physician.
—JP Schlingman
Related Information:
How Knowing Your Genetic Code Could Lengthen Your Life
Genome in the Palm of Your Hand
Molecular Machines and the Place of Physics in the Biology Curriculum
Oxford Nanopore’s Hand-Held DNA Analyzer Has Traveled the World
Hostplus Sinks $27m Into Hand-held DNA Sequencing Firm Oxford Nanopore
GIC, Others Invest £100m In Hand-held DNA Sequencing firm Oxford Nanopore
Handheld Device Sequences Human Genome
Breakthrough Leads to Sequencing of a Human Genome Using a Pocket-sized Device
Oxford Nanopore’s Tech Reaches Genome Sequencing Landmark
Point-of-Care DNA Sequencer Inching Closer to Widespread Use as Beta-Testers Praise Oxford Technologies’ Pocketsize, Portable Nanopore Device
$900 Point-of-Care DNA Nanopore Sequencer May Hit Market in Next 12 Months
Is Whole-genome Sequencing Reaching a Tipping Point for Clinical Pathology Laboratories?
Jul 9, 2018 | Instruments & Equipment, Laboratory Instruments & Laboratory Equipment, Laboratory Management and Operations, Laboratory News, Laboratory Operations, Laboratory Testing, News From Dark Daily
Could biometrics increase security and safety of clinical laboratory patient identification and specimen tracking processes as well?
Positive patient identification is a common problem for all healthcare providers, including medical laboratories. That is why there is strong interest in developing technologies that use biometric data to identify patients. The challenge has been to find a biometric solution that has acceptable accuracy and can make the positive identification in a speedy fashion, particularly when the patient presents for service or to provide a clinical laboratory specimen.
One Canadian company believes it has a biometrics-based solution almost ready to bring to market. AceAge, Inc., a Canadian healthcare technology company, recently added facial recognition software to their Karie at-home medication dispensing appliance, according to Biometric Update. The Ver-ID facial recognition authentication application they chose was developed by Ontario-based Applied Recognition, Inc.
Karie (above right) is designed to help patients accurately schedule, monitor, and take their medications. The companion facial recognition software—one of several security features—will enable homebound individuals who use mobile devices or the Internet to electronically sign-in and notify caregivers that medication was taken as ordered, an AceAge news release noted. “Now, our end users can dispense their prescriptions at a glance and without worry that, for example, a child might inadvertently get access. This will help bring security to medication in people’s homes,” Spencer Waugh, AceAge’s CEO (above), stated in the news release. (Image copyright: AceAge.)
The new Karie automated solution, is expected to launch later this year. Developers anticipate that the facial recognition feature also could be of value to researchers in late-stage clinical trials, where documentation of medication adherence is critical.
How Does Facial Recognition Software Work?
According to Applied Recognition, Ver-ID uses an algorithm that is more than 99% accurate in detecting and recognizing faces. Here’s how it works:
- A patient registers his or her face using the camera on a mobile device or camera-enabled computer;
- The patented Ver-ID algorithm matches 75 points and creates a “facial print” or “signature,” capturing unique features;
- Then, as the person uses their mobile device or computer, the facial signature is authenticated against the registered signature to control access to the app or device.
AceAge’s Karie device would authenticate the patient’s facial image against a stored facial signature in the same manner.
Fingerprint Readers Give People Identity, Care Access in Africa
Danny Thakkar, co-founder of Bayometric of San Jose, Calif., a global provider of fingerprint scanners and biometric software, says biometrics improves patient identification and is faster and more reliable than manual identification of patient records in a master patient index.
“The process of patient enrollment and admission becomes fast and hassle-free as a simple biometric scan is all it takes to identify and admit a patient,” Thakkar noted in a blog post.
In fact, biometrics technology has made it possible for residents of developing countries, without driver licenses or credit cards, to secure identity and access to healthcare services, according CNN.
COHESU, a Kenyan community health charity, is reportedly working with Simprints, a nonprofit technology company in the UK that makes fingerprint scanners for mobile platforms and charities worldwide, to implement biometrics for patient identification.
After having their fingerprints registered by the Simprints biometric scanner, Kenyan patients receive a unique identifier that can be matched to their healthcare records. Caregivers use mobile apps to access their patients’ health records and review or update them, CNN reported.
“Biometrics as a technology has completely changed our way of thinking. Without it, they would probably stay at home and accept their fate,” Nicholas Mwaura, a systems and database administrator with COHESU told CNN.
Hospitals Have Outdated Patient ID Methods, Says HealthsystemCIO Survey
Meanwhile, 42% of hospital CIOs acknowledged in an Imprivata/HealthsystemCIO.com survey that patient matching is a top priority at their organizations, according to a news release. Another 24% of CIOs surveyed said patient matching is not a priority, but it should be.
“Many hospitals still rely on methods that do not guarantee accurate patient identification, such as a person’s date of birth or a health insurance card. By implementing a registration solution—such as biometric identification technology—that accurately identifies patients and matches them with their correct EMPI (enterprise master patient index) and EHR (electronic health record) records, hospitals can reduce the very real risks highlighted in this survey,” Sean Kelly, MD, Imprivata’s Chief Medical Officer, told EHR Intelligence.
Clinical laboratory leaders already use processes and software to identify patients and match them with records and specimens. In the near future, biometric facial recognition might provide additional patient identification, safety, and medical laboratory security.
—Donna Marie Pocius
Related Information:
Medication Delivery Device Maker Adds Ver-ID for Biometric Patient Verification
AceAge Selects Applied Recognition to Provide Face Recognition Technology for Biometric Identity Authentication
Biometrics for Accurate Patient Identification
How Biometrics is Giving Identities to ‘Invisible Citizens’
Mismatched Patient Records: An Under-Recognized and Growing Problem at Most Hospitals, Imprivata CIO Survey Finds
42% of Healthcare CIOs List Patient Matching Issues a Top Priority
Jul 6, 2018 | Instruments & Equipment, Laboratory Instruments & Laboratory Equipment, Laboratory News, Laboratory Operations, Laboratory Pathology, Laboratory Testing
Analysis performed by this new biosensor could help identify inflammatory bowel diseases, cancer, and other chronic diseases, and contribute to influencing the best treatment options, a critical aspect of personalized medicine
Anatomic pathologists and clinical laboratories have long known that disease, as the saying goes, “is written in the blood.” How to spot the disease has been the challenge.
Now, researchers at Finland’s Aalto University have developed a cutting-edge plasmonic biosensor that uses the intense light absorption and reflective properties of plasmonic materials to discern refractive changes between healthy and diseased exosomes—even with the naked eye!
This opens the door to a plethora of non-invasive health tests similar to home pregnancy tests. Should such tests prove accurate and affordable, medical laboratories could have new tools in their fight to end chronic disease.
New Rules for Differentiating Healthy and Diseased Human Exosomes
The Aalto researchers produced the biosensor by depositing plasmonic metaparticles (hypothetical particles that always move faster than light, such as Tachyons) on a black metal surface capable of absorbing electromagnetic radiation. With it, abnormalities can be distinguished by the color generated when the plasmons impact the black surface.
“We exploited it as the basis of new design rules to differentiate diseased human serum exosomes from healthy ones in a simple manner with no need [for] any specialized equipment”, Dr. Abdou Elsharawy, PhD, Postdoctoral Researcher at Kiel University in Kiel, Germany, stated in an Aalto University news release.
Researchers at Aalto University in Finland have developed a method for “visualizing the specular reflection color by a blackbody substrate. The carriers containing Ag nanoparticles [shown above] are covered with various dielectrics of AlN [aluminum nitride], SiO2 [silicon dioxide], and the composites thereof that are placed on a black background to enhance the reflectivity contrast of various colors at a normal angle of incidence.” This has resulted in a tool that medical laboratories could use to differentiate between healthy and diseased exosomes in human blood. (Photo and caption copyrights: Aalto University.)
Dr. Mady Elbahri, PhD, Professor, Nanochemistry and Nanoengineering, Department of Chemistry and Materials Science at Aalto University, indicated that there is no need to use sophisticated fabrication and patterning methods with the biosensor as bulk biodetection of samples can be seen with the naked eye.
“It is extraordinary that we can detect diseased exosomes by the naked eye. The conventional plasmonic biosensors are able to detect analytes solely at a molecular level. So far, the naked-eye detection of biosamples has been either rarely considered or unsuccessful,” Elbahri noted in the news release.
Exosomes Critical to Many Human Bodily Processes
Exosomes are cell-derived vesicles that are present in many and perhaps all eukaryotic fluids, including blood, urine, and cultured medium of cell cultures. These small bundles of material are released by the outer wall of a cell and contain everything from proteins to ribonucleic acid (RNA) and Messenger RNA (mRNA). They are important indicators of health conditions.
There is mounting evidence that exosomes have exclusive functions and perform a significant role in bodily processes like coagulation, intercellular signaling, and waste management.
Interest in the clinical applications of exosomes is increasing, along with their potential for use in prognosis, development of therapies, and as biomarkers for diseases. But, exosomes are rare and distinguishing them among all other elements located in bodily fluids has proven difficult.
Thus, the Aalto study has strong implications for clinical laboratories and anatomic pathology groups. More research and regulatory approval will be needed before use of this new tool comes to fruition. However, any method that accurately and inexpensively identifies chronic disease biomarkers will impact the medical laboratory and anatomic pathology professions and is worth watching
—JP Schlingman
Related Information:
Plasmonic Biosensors Enable Development of New Easy-to-use Health Tests
Plasmonic Biosensor to Detect Exosomes with Naked Eye
Plasmonic Metaparticles on a Blackbody Create Vivid Reflective Colors for Naked‐Eye Environmental and Clinical Biodetection
Plasmonic Biosensors
Jun 27, 2018 | Digital Pathology, Instruments & Equipment, Laboratory Instruments & Laboratory Equipment, Laboratory Management and Operations, Laboratory News, Laboratory Operations, Laboratory Pathology, Laboratory Testing, Management & Operations
Using GPIIb/IIIa inhibition, and ion chelation, researchers have developed a “universal” method for preserving blood up to 72 hours while keeping it viable for advanced rare-cell applications
Through microfluidics and automation, clinical laboratories and anatomic pathologists have been able to detect ever-smaller quantities of biomarkers and other indicators of chronic disease.
However, preserving sample quality is an essential part of analytical accuracy. This is particularly true in precision oncology and other specialties where isolating rare cells (aka, low abundance cells), such as circulating tumor cells (CTCs), is a key component to obtaining information and running diagnostics.
Publishing their finding in Nature, researchers at Massachusetts General Hospital Center for Engineering in Medicine (MGH-CEM) have developed a whole blood stabilization method that is ideal for rare-cell applications, and which preserves sample integrity for up to 72 hours.
Should further testing validate their findings and methodology, this change could allow greater use of central laboratories and other remote testing facilities that previously would not be available due to distance and sample travel time.
Keeping Blood Alive Is Not Easy
“At Mass. General, we have the luxury of being so integrated with the clinical team that we can process blood specimens in the lab typically within an hour or two after they are drawn,” stated lead author Keith Wong, PhD, former Research Fellow, MGH-CEM, and now Senior Scientist at Rubius Therapeutics, Boston, in a Mass General press release. “But to make these liquid biopsy technologies routine lab tests for the rest of the world, we need ways to keep blood alive for much longer than several hours, since these assays are best performed in central laboratories for reasons of cost-effectiveness and reproducibility.”
Study authors Wong and co-lead author Shannon Tessier, PhD, Investigator at MGH-CEM, noted that current FDA-approved blood stabilization methods for CTC assays use chemical fixation—a process that can result in degradation of sensitive biomolecules and kill the cells within the sample.
Without stabilization, however, breakdown of red cells, activation of leukocytes (white blood cells), and clot formation can render the results of analyzing a sample useless, or create issues with increasingly sensitive equipment used to run assays and diagnostics.
“We wanted to slow down the biological clock as much as possible by using hypothermia, but that is not as simple as it sounds,” says Tessier. “Low temperature is a powerful means to decrease metabolism, but a host of unwanted side effects occur at the same time.”
Researchers started by using hypothermic treatments to slow degradation and cell death. However, this created another obstacle—aggressive platelet coagulation. By introducing glycoprotein IIb/IIIa inhibitors, they found they could minimize this aggregation.
Keith Wong, PhD (left), a former Research Fellow, MGH-CEM, and now Senior Scientist at Rubius Therapeutics in Boston; and Shannon Tessier, PhD (right), Investigator at MGH-CEM, co-authored a study to develop a whole blood stabilization method that preserves sample integrity for up to 72 hours, making it possible to transport blood specimens further distances to central clinical laboratories for processing. (Photo copyrights: LinkedIn.)
Prior to microfluidic processing of their test samples, researchers applied a brief calcium chelation treatment. The result was efficient sorting of rare CTCs from blood drawn up to 72 hours prior, while keeping RNA intact and retaining cell viability.
“The critical achievement here,” says Tessier, “Is that the isolated tumor cells contain high-quality RNA that is suitable for demanding molecular assays, such as single-cell qPCR, droplet digital PCR, and RNA sequencing.”
Their testing involved 10 patients with metastatic prostate cancer. Sample integrity was verified by comparing CTC analysis results between fresh samples and preserved samples from the same patients using MGH-CEM’s own microfluidic CTC-iChip device.
Results showed a 92% agreement across 12 cancer-specific gene transcripts. For AR-V7, their preservation method achieved 100% agreement. “This is very exciting for clinicians,” declared David Miyamoto, MD, PhD, of Massachusetts General Hospital Cancer Center in the press release. “AR-V7 mRNA can only be detected using CTCs and not with circulating tumor DNA or other cell-free assays.”
Methodology Concerns and Future Confirmations
“Moving forward, an extremely exciting area in precision oncology is the establishment of patient-specific CTC cultures and xenograft models for drug susceptibility,” the study authors noted. “The lack of robust methods to preserve viable CTCs is a major roadblock towards this Holy Grail in liquid biopsy. In our preliminary experiments, we found that spiked tumor cells in blood remain highly viable (>80%) after 72 hours of hypothermic preservation.”
Despite this, they also acknowledge limitations on their current findings. The first is the need for larger-scale validation, as their testing involved a 10-patient sample group.
Second, they note that further studies will be needed to “more completely characterize whole-transcriptome alterations as a result of preservation, and to what extent they can be stabilized through other means, such as further cooling (e.g., non-freezing sub-zero temperatures) or metabolic depression.”
Researchers also note that their approach has multiple advantages for regulatory approval and further testing—GPIIb/IIIa inhibitors are both low-cost and already approved for clinical use, implementation requires no modification of existing isolation assays, and cold chain protocols are already in place allowing for easy adaptation to fit the needs of pathology groups, medical laboratories, and other diagnostics providers handling samples.
While still in its early stages, the methods introduced by the researchers at MGH-CEM show potential to allow both the facilities collecting samples and the clinical laboratories processing them greater flexibility and increased accuracy, as high-sensitivity assays and diagnostics continue to power the push toward personalized medicine and expand laboratory menus across the industry.
—Jon Stone
Related Information:
Whole Blood Stabilization for the Microfluidic Isolation and Molecular Characterization of Circulating Tumor Cells
Improved Blood Stabilization Should Expand Use of Circulating Tumor Cell Profiling
Genentech Scientists Zero In on “Liquid Biopsies” as a Way to Replace Tissue Biopsies in Breast Cancer
University of Michigan Researchers Use “Labyrinth” Chip Design in Clinical Trial to Capture Circulating Tumor Cells of Different Cancer Types
Super-Fast Microscope Captures Circulating Tumor Cells with High Sensitivity and Resolution in Real Time
