Friday, November 01, 2019

Researchers Develop Affordable New Test For Dengue

Researchers have developed a user-friendly dengue test that could help diagnose the growing tropical disease more quickly and efficiently. Every year, nearly 400 million people are infected by dengue, a mosquito-borne disease that continues to spread in tropical climates. While a quarter of those patients will experience flu-like illness, a small fraction could develop severe dengue, a potentially fatal condition.

In a new study, University of Alberta Canada researchers said they have developed an affordable one-step test for dengue that requires just a small blood or plasma sample and a portable tester.

"You could take somebody's blood and run a single test to see what they have," said Ninad Mehta, lead author of the study. "You would know in about two hours what it is." Mehta conducted the study while working in the University of Alberta school of Public Health under Stephanie Yanow, who has spent years working on diagnostic tests for malaria, Medical Xpress reported.

Diagnosis is one of the biggest challenges in treating tropical fevers. Early dengue symptoms resemble malaria, chikungunya, Zika and other diseases. Rapid diagnostic tests can detect antigens or proteins, but they aren't always specific enough and can lead to false positives. More precise diagnosis requires expensive equipment, multiple steps and training. In remote areas where the disease is rampant, it's not always feasible.

Mehta's dengue test would combine the best of both worlds: a highly specific test that's affordable and portable.

It depends on a molecular technique called RT-PCR, which involves finding a stable sequence of viral RNA, translating it into DNA and multiplying the genetic material to the point where it can be detected. It piggybacks on the growing availability of Open PCR machines, a versatile DNA-detection technology that has become cheaper thanks to crowdfunding and open-source technology.

Because there are four distinct variants of the dengue virus, Mehta had to find specific genetic material common to all four but not found in viruses with similar symptoms. He focused on a 253-nucleotide sequence of RNA, which was tested on 126 archived samples from a dengue study in the Philippines. The results were compared with other types of testing.

The test held up well to existing kits, particularly in the first four days of symptoms when the presence of the virus is highest. At under $5 per test, Mehta believes this testing could help public health agencies get better bang for their buck.

"When you start treating one disease, another pops up," Mehta said. "It's a game about shifting resources whenever you can."Mehta hopes his work could help save lives, but he recognizes it still could be years away. Because the new dengue test requires cold chemicals, Yanow's lab is looking at using vacuum-drying to create a powder that could withstand the heat in tropical settings. More work will be needed for field trials.

T2 Biosystems’ T2Resistance™ Panel is First Diagnostic to Graduate from CARB-X Portfolio

T2 Biosystems, Inc., a leader in the development and commercialization of innovative medical diagnostic products for critical unmet needs in healthcare, and CARB-X, a global non-profit partnership dedicated to accelerating early development antibacterial R&D to address the rising global threat of drug-resistant bacteria, announced today that the T2Resistance™ Panel is the first diagnostic to graduate from CARB-X’s portfolio. The graduation marks an important milestone on the path toward approval for use on patients in hospitals in the U.S., Europe and elsewhere around the globe.

In 2017, CARB-X awarded T2 Biosystems $2.0 million to support the development of the T2Resistance Panel, designed to detect 13 resistance genes from both gram-positive and gram-negative pathogens directly from a whole-blood specimen, without the need to wait for blood cultures. The panel was granted Breakthrough Device designation by the Food and Drug Administration (FDA) earlier this year and is expected to be available for research use only (RUO) in the US by the end of Q3 2019 and receive CE-Mark for commercial availability in Europe by the end of 2019.

“Addressing the global superbug crisis requires urgent development of innovative diagnostics, like T2’s technology, as well as new drugs and vaccines. This is the first diagnostic to graduate from CARB-X’s portfolio, and we are excited that we could help T2 with funding and support to develop this technology,” said Kevin Outterson, Executive Director of CARB-X, which is based at the Boston University School of Law. “The T2Resistance Panel will provide healthcare professionals with a new rapid test, a first of its kind, to provide timely and accurate detection of drug-resistant infections and inform treatment decisions to ensure patients are given the most appropriate care.”

“We are incredibly grateful to CARB-X for the funding and support they provided to our team in the development of the T2Resistance Panel over the past year and a half,” said John McDonough, chairman and chief executive officer of T2 Biosystems. “Rapid identification of the genes and species associated with antibiotic resistance can help enable the reduction of unnecessary antibiotic use, which is the primary cause of resistance. Being the first diagnostic to graduate from CARB-X’s portfolio is a significant milestone in the development of technology that has such capabilities.”

The T2Resistance Panel identifies 13 of the most serious superbugs and resistance genes on the antibiotic-resistance threat list published by the Centers for Disease Control and Prevention (CDC), including genes indicating resistance to common empiric antibiotic therapies such as carbapenems, vancomycin, penicillin and more.

Diagnosing infections faster means saving lives and fighting the spread of superbugs

Bacterial bloodstream infections can be deadly even at low concentrations. If bacterial infections are identified quickly, patients can be placed on effective antibiotic therapy faster. T2MR technology enables rapid identification of bacterial pathogens and resistance markers directly in whole blood within three to five hours. Existing diagnostics rely primarily on blood cultures conducted in laboratories, which can take days, and do not always produce reliable results. As a result, physicians are often unable to treat infections quickly with the appropriate antibiotics, leading to higher mortality and use of unnecessary antibiotics.

T2 Biosystems is the company behind the T2Bacteria Panel, which was the first in-vitro diagnostic test to receive approval for a New Technology Add-on Payment (NTAP) by the United States Centers for Medicare & Medicaid Services (CMS). The panel is the only FDA-cleared test to identify sepsis-causing bacterial pathogens directly from whole blood without the need to wait for blood culture, and its counterpart for fungal bloodstream infections is the T2Candida Panel, the first and only FDA-cleared direct-from-whole blood diagnostic for detection of fungal pathogens that are associated with sepsis. Both panels provide results in three to five hours instead of days. The products are two of several panels that are approved or in development that are run on the Company’s T2Dx® Instrument, which is powered by miniaturized magnetic resonance (T2MR®) technology.

The CARB-X graduation news follows the recent announcement that T2 Biosystems has been awarded a milestone-based contract of initial value of $6 million with a potential value of up to $69 million, if all contract options are exercised, from the Biomedical Advanced Research and Development Authority (BARDA), within the Office of the Assistant Secretary for Preparedness and Response (ASPR) at the US Department of Health and Human Services’ (HHS). BARDA is also the main US founder and funder of CARB-X.

Supporting innovation in the race against drug-resistant bacteria

Drug-resistant infections are responsible for an estimated 700,000 deaths worldwide each year, according to the World Health Organization (WHO).

The CARB-X portfolio is the world’s largest early development portfolio addressing drug-resistant bacteria, with 31 active projects. In the three years since its launch, CARB-X has funded and supported 48 innovative projects, for a total obligation of over $139.4 million with the potential of additional funds if project milestones are met. These funds are in addition to investments made by the companies themselves. The CARB-X pipeline will continuously evolve, as projects progress and graduate from CARB-X and others fail for a variety of reasons. The current portfolio supports 13 new classes of antibiotics, 15 new molecular targets, 12 non-traditional approaches including microbiome-based therapeutics, four diagnostics and three vaccines.

CARB-X is investing up to $500 million in antibacterial R&D between 2016-2021. The goal is to support projects in the early phases of development, so that they will attract additional private or public support for further clinical development and approval for use in patients. CARB-X funding is restricted to projects that target drug-resistant bacteria highlighted on the CDC’s 2013 Antibiotic Resistant Threats list, or the Priority Bacterial Pathogens list published by the WHO in 2017.

CARB-X is led by Boston University and funding is provided by BARDA, the Wellcome Trust, Germany’s Federal Ministry of Education and Research (BMBF), the UK Department of Health and Social Care’s Global Antimicrobial Resistance Innovation Fund (UK GAMRIF), the Bill & Melinda Gates Foundation, and with in-kind support from National Institute of Allergy and Infectious Diseases (NIAID).

Portable DNA Sequencer Quickly and Accurately Diagnoses Wheat Viruses

A group of scientists in Kansas, based at The Agricultural Research Service of the US Department of Agriculture (USDA-ARS) and Kansas State University, have developed a new technology that makes it possible to rapidly identify viruses in wheat fields with a higher level of accuracy.

It is said that blast, a disease that results from a fungus that infects the wheat spikes in the field, turning the grain to inedible chaff, cause significant loses in wheat crops. Recently, Bangladesh was devastated by an invasion of South American races of wheat blast fungus, which occurred for the first time in the country in 2016. The disease spread to an estimated 15,000 hectares (16 percent of cultivated wheat area in the country) and resulted in yield losses as high as 100 percent.

Diagnosis of crop disease is considered crucial but traditional methods rely on the expertise of pathologists, who in turn rely on the physical appearance of disease symptoms, which can be similar to damage caused by other factors, such as nutrient deficiencies or environmental elements. Pathologists also experience difficulty detecting coinfections and pathogens that do not infect aerial parts of the plant.

Rapid detection is also considered a key issue for identifying unknown pathogens during an outbreak, as was made clear during the wheat blast fungus outbreak in Bangladesh.

The Kansas scientists collected four wheat samples from western Kansas and used a new “harmonica-sized” DNA sequencer and a computer programme to quickly detect three different viruses in the samples. The results suggested that the samples contained a new virus strain.

The scientists are now working on improving the technique so that it can be used in field applications. Their research, described in ‘Wheat Virus Identification Within Infected Tissue Using Nanopore Sequencing Technology,’ published in the September 2019 issue of Plant Disease, is the first report of using the new portable DNA sequencing technology for wheat virus identification. These results hope to have broad application to plant and animal disease identification and field diagnostics technology in the near future.

Faster Identification of Bacterial Infections Using Raman Spectroscopy Could Save Lives

Utilizing a Renishaw Raman spectroscopy system, a team of researchers from the Czech Academy of Sciences have been testing a novel way to identify Staphylococcal bacteria, paving the way for faster diagnosis and treatment of infectious diseases.

Staphylococci are a type of bacteria commonly found on the skin and hair of humans and mammals. They are usually harmless, however some strains, such as Staphylococcus aureus (S. aureus), can cause more serious infections if they are able to enter the body. The management of patients with bacterial infections relies on the early detection and identification of pathogens, as it enables the appropriate administration of antibiotics which saves lives. In the case of more serious conditions, such as sepsis, treatment should be started within an hour of the diagnosis. Unfortunately, current tests often take days to complete, putting lives at risk.

Dr. Ota Samek heads a Biophotonics and Optofluidics group at the Institute of Scientific Instruments within the Czech Academy of Sciences. The group has been using Raman spectroscopy to speed up the identification of bacterial infections and are hoping to introduce this method to hospitals as a tool for clinical diagnosis.

The team’s initial study focused on using Raman spectroscopy to identify staphylococci strains from bacterial colonies grown on an agar plate. Using a Renishaw inVia™ Raman microscope, the researchers acquired Raman spectra for 277 different staphylococcal strains and were able to differentiate between 16 species of staphylococci with almost 100% accuracy. This led to further research on the two most common infection-causing species of staphylococci – S. aureus and S. epidermidis. The team found that Raman spectroscopy techniques enabled them to rapidly and reliably distinguish between the strains.

The group’s success in identifying strains of staphylococci using Raman spectroscopy inspired further studies into whether the technique could also be used to investigate bacterial biofilms. Biofilms provide microorganisms with their own microenvironment that helps them survive within a host organism. They can be found on objects such as catheters, cannulas, artificial heart valves and even contact lenses. In this study, the team selected bacterium Staphylococcus epidermis and yeast Candida parapsilosis and used the inVia Raman microscope to distinguish between biofilm-positive- and biofilm-negative-strains directly from colonies grown on agar plates.

Dr. Samek has been using Renishaw Raman instruments to study staphylococci since 2007 when he spent two years at Swansea University, sponsored by a Marie-Curie Intra-European Fellowship. He noted the strong relationships between Renishaw and Swansea University and this encouraged him to connect with Renishaw on his return to the Czech Republic.

Published Papers on the Research

  • K. Rebrosova, M. Siler, O. Samek, F. Ruzicka, S. Bernatova, V. Hola, J. Jezek, P. Zemanek, J. Sokolova, P. Petras: Rapid identification of staphylococci by Raman spectroscopy, Scientific Reports 7, 14846, 2017.
  • K. Rebrosovsa, M. Siler, O. Samek, F. Ruzicka, S. Bernatova, J. Jezek, P. Zemanek, V. Hola: Differentiation between Staphylococcus aureus and Staphylococcus epidermidis strains using Raman spectroscopy, Future Microbiology 12, 881-890, 2017.
  • K. Rebrošová, M. Šiler, O. Samek, F. Růžička, S. Bernatová, J. Ježek, P. Zemánek,  V. Holá,  Identification of ability to form biofilm in Candida parapsilosis and Staphylococcus epidermidis by Raman spectroscopy. Future Microbiology 14,  509–518, 2019

IIT Delhi Researchers Developing Technology for Rapid Diagnosis by Reducing Antibacterial Resistance

Researchers at IIT Delhi are working on a technology to devise diagnostic solutions for combating the problem of antimicrobial resistance to enable rapid diagnosis of bacterial infection and guide clinical decision making.
According to the team at IIT, the research will greatly reduce the unnecessary use of antimicrobials in diagnostic tests and minimise the development of resistance as currently there is a big knowledge gap in microbial resistance biology and the availability of biomarkers and technology for rapid diagnostics.

"Antibacterial resistance is now widely recognised as the biggest healthcare problem of this century. Due to limitations in the current microbiological methods, it is estimated that more than two-thirds of antibiotic prescriptions are unnecessary and are empirical in nature. This practice is a major cause of the emergence of AMR and its rapid spread in the last decade," said IIT professor Vivekanandan Perumal, who is the Principal Investigator (PI) of the project.

"Although the requirement of rapid pathogen identification and methods for antimicrobial susceptibility testing (AST) are well recognized, major limitations include the knowledge gaps in understanding the genomic signatures and their correlation with Antimicrobial Resistance (AMR)," he added.

The research team will focus on 4 major pathogens (Staphylococcus aureus, Klebsiella pneumonia, Acinetobacter baumanii, Pseudomonas aeruginosa) that are often resistant to antibiotics in Indian clinical settings.

The main objectives of the research project include -- characterization of AMR among Indian isolates using whole-genome sequencing of clinical isolates and optical genome mapping for pathogen identification using a unique genome-based signature for microbial typing with the optical mapping of DNA fragments.

"The research will also look into development of methods for rapid antimicrobial susceptibility testing by carrying out the pH measurements inside spherical microgels microreactors with embedded pH-sensitive carbon dot nanosensors and identification of bacteria species and spread of AMR using clothes worn by HCWs (healthcare workers) with a rapid culture-independent method based on bacterial 16s RNA," Perumal said.

Wednesday, October 16, 2019

Pittsburgh Research Team Uses Rapid Diagnosis Technology to Tackle HIV Testing Problems

As associate medical director of clinical immunopathology at the University of Pittsburgh Medical Center, Sarah Wheeler has received many calls from clinicians about diagnostic testing in the hospital, including those dealing with human immunodeficiency virus.

However, one call made her realize the limits of modern medical technology.

“We received a call from (UPMC) Magee–Womens Hospital that a woman was in active labor with no prior medical history and no baseline infectious disease testing, and we didn’t have any tests that could provide us an accurate result for her HIV status that could be done rapidly,” said Wheeler, who is also an assistant professor of pathology at Pitt.

This isn’t an uncommon scenario, but it was the event that led to Wheeler and other Pitt researchers taking action. She, along with Michael Shurin, a fellow professor of pathology, and Alexander Star, professor of chemistry at Pitt, are creating a testing device that will be able to determine in one minute whether a patient is infected with HIV. Currently, early HIV screening takes 1,440 minutes — an entire day.

Michael Shurin, professor of pathology, is part of the team that created the HIV Detective, a device for giving a rapid diagnosis for HIV infection.
“We thought, ‘We should be able to do something better,’” Shurin said.

Shurin’s tenure in the clinical laboratory took him through the earliest tests for HIV, and he has seen the progress to date in these tests as helpful, but inadequate for the clinical situations he now faces as division director of clinical immunopathology. Building on his decade-long collaboration in cancer research with Star, Shurin started pulling together a team to tackle this problem.

The HIV Detective is the team’s solution to the need for early and rapid diagnosis of HIV. It is a testing platform that would fit in the palm of a hand and allows health care workers to gather a few drops of blood from a patient onto a sensor smaller than Roosevelt’s ear on the dime and provides an HIV screening result in one minute.

This leap forward in testing is possible due to another recent project from the Star laboratory, a working THC breath test.

The THC-detection technology hinges on carbon nanotubes, tiny tubes of carbon 100,000 times smaller than a human hair, which are capable of conducting electricity and monitoring molecular interactions.

“Think of it like wires connected to molecules,” said Star. “The detection is really fast.”

Using the same technology in the HIV Detective means the team members don’t have to wait for the lengthy and insensitive chemical reactions currently used in testing; they can get real-time results from HIV antigen-antibody binding. This allows for a fast and accurate test, as Star’s team has demonstrated with their successful breathalyzer test that also helps in diagnosing and monitoring Type 1 diabetes in patients.

The technology also would allow the team to make the HIV Detective device cost-efficient, which could benefit HIV patients in other countries who cannot afford access to testing. About 34 million people worldwide have the virus.

Patients are most infectious when they first contract HIV, but current rapid tests do not detect HIV in this acute stage — about two to four weeks in. According to the Centers for Disease Control and Prevention, of the 1.1 million people who have HIV in the U.S., about 20% remain unaware they have the virus during this stage because they show no symptoms.

It was this message that helped the HIV Detective team win a $100,000 grand prize from the 2019 Pitt Innovation Challenge (PInCh), hosted by Pitt’s Clinical and Translational Science Institute (CTSI). The prize money will enable the team to create a prototype and use it for clinical trials.

“Our ultimate goal is approval from the Food and Drug Administration, so it can be used across the country,” Wheeler said.

“The PInCh competition provides the opportunity for University teams to identify important medical and public health problems and address those problems with unique solutions,” said CTSI director Steven Reis, who also is associate vice chancellor for clinical research and health sciences, and a professor of medicine at Pitt. “This year’s winners — including HIV Detective — proved, once again, that through creative thinking by diverse research teams, discoveries can be applied to address real world health challenges.”

FDA Allows Marketing of First Rapid Diagnostic Test for Detecting Ebola Virus Antigens

The U.S. Food and Drug Administration allowed marketing of a rapid diagnostic test (RDT) to detect Ebola virus antigens (proteins) in human blood from certain living individuals and samples from certain recently deceased individuals suspected to have died from Ebola (cadaveric oral fluid). The OraQuick Ebola Rapid Antigen Test is the first rapid diagnostic test the FDA has allowed to be marketed in the U.S. for the Ebola Virus Disease (EVD). The test provides a rapid, presumptive diagnosis that must be confirmed.

“Today’s marketing authorization provides another important tool in the effort to fight Ebola, which continues to be a priority of the U.S. Government, especially as we work with our partners, including the World Health Organization, to help address the current Ebola outbreak in the Democratic Republic of Congo (DRC),” said Acting FDA Commissioner Ned Sharpless, M.D. “The current outbreak in the DRC has already killed thousands and the outbreaks in West Africa that began in 2014 tragically killed more than 11,000. Investigational vaccines and therapeutics have shown promising results, but one of the most important tools in stopping these outbreaks is quickly diagnosing patients and supporting safe and dignified burials. This marketing authorization may provide additional assurances to health care professionals seeking to use these types of rapid diagnostics. The ability to use this test to promptly make a presumptive Ebola diagnosis could help providers to more quickly isolate patients and begin treatments that can be potentially life-saving. Additionally, this device could be used to support safe and dignified burials while helping to reduce the risk of transmission during those burials.”

EVD, which is caused by the Ebola virus, is a severe, often fatal disease in humans that can spread through direct contact with blood or body fluids or objects contaminated with body fluids, as well as from the bodies of those who have died from the virus. EVD has led to several large outbreaks in Africa, including the West African Ebola epidemic that began in 2014 and was the largest outbreak of EVD in recorded history, and the ongoing outbreak in the DRC, which is currently the second largest outbreak. Extensive efforts are underway by the Ministry of Health in the DRC to contain the current outbreak with support from the World Health Organization, the U.S. government, and other partners. These measures include campaigns to promote good hygiene, large-scale vaccination campaigns, specialized Ebola treatment centers where those infected or exposed to the virus can receive investigational therapeutics, and comprehensive efforts to trace and prevent the spread of EVD through vaccination campaigns, monitoring for symptoms, diagnostic testing, and implementation of infection prevention and control measures, such as safe and dignified burial procedures.

During the 2014 outbreak, the Secretary of the Department of Health and Human Services declared that circumstances exist justifying the authorization of emergency use of in vitro diagnostics for detection of Ebola virus. At the time, the FDA worked with CDC and test developers to make diagnostic tests, including the OraQuick Ebola Test, available through the Emergency Use Authorization (EUA) pathway. This pathway allows the FDA to temporarily authorize the use of unapproved medical products to address a public health emergency when specific conditions are met, including that there are no adequate, approved and available alternatives to the product for diagnosing, preventing, or treating the disease or condition. The FDA has authorized a number of diagnostic tests for EVD under the EUA pathway to assist with the public health response. Today’s marketing authorization of the first EVD presumptive rapid diagnostic test for Ebola virus antigens through the De Novo review pathway reflects the ongoing collaboration between the U.S. Government and test developers to gather additional data on EUA products.

For the OraQuick Ebola Test submission, the FDA reviewed data from multiple clinical studies of blood samples and cadaveric oral fluid from the 2014 West African outbreak and from a variety of analytical studies. Based on these data, the FDA determined that general and special controls were necessary to provide a reasonable assurance of the safety and effectiveness of the OraQuick Ebola Test when intended to identify antigens associated with Ebola virus in blood from symptomatic patients and oral fluid of cadavers. The amount of Ebola virus when patients have severe symptoms of EVD is usually high; however, the amount of virus in samples taken early after infection when symptoms are not present yet or taken early during the course of EVD when symptoms are mild can be very low. The studies demonstrated the importance of testing only symptomatic individuals so that the amount of virus is high enough to be detectable by this test. Therefore, the OraQuick Ebola Test is intended for use in patients suspected of and with signs or symptoms consistent with EVD, and when the patient meets the CDC’s Ebola virus epidemiological criteria, such as history of residence in or travel to a geographic region with active EVD transmission at the time of travel. The OraQuick Ebola Test is not intended to be used for general Ebola infection screening (e.g., airport screening) or testing of individuals at risk of exposure without observable signs of infection.

The OraQuick Ebola Test may also be used in recently deceased individuals (cadaveric oral fluid) with epidemiological risk factors (including geographic locations with high prevalence of EVD) suspected to have died of EVD to inform decisions on safe handling of cadavers to prevent disease transmission.

Negative results do not rule out Ebola virus infection. The definitive identification of EVD requires additional testing and confirmation procedures (such as by a more sensitive but less rapid polymerase chain reaction test) and in consultation with public health and/or other authorities to whom reporting is required.

The OraQuick Ebola Test was reviewed under the De Novo premarket review pathway, a regulatory pathway for low-to-moderate-risk devices of a new type. Along with this marketing authorization, the FDA is establishing criteria, called special controls, that determine the requirements for demonstrating accuracy, reliability and effectiveness of tests intended to identify Ebola virus antigens. These special controls, when met along with general controls, provide a reasonable assurance of safety and effectiveness for tests of this type. This action also creates a new regulatory classification, which means that subsequent devices of the same type with the same intended use may go through the FDA’s 510(k) pathway, whereby devices can obtain clearance by demonstrating substantial equivalence to a predicate device.

The OraQuick Ebola Test was granted Breakthrough Device designation, meaning the FDA provided intensive interaction and guidance to the company on efficient device development, to expedite evidence generation and the agency’s review of the device. To qualify for such designation, a device must provide for more effective treatment or diagnosis of a life-threatening or irreversibly debilitating disease or condition, and meet one of the following criteria: the device must represent a breakthrough technology; there must be no approved or cleared alternatives; the device must offer significant advantages over existing approved or cleared alternatives; or the availability of the device is in the best interest of patients.

The FDA granted marketing authorization of the OraQuick Ebola Test to OraSure Technologies, Inc.

Microfluidic Device for Rapid Lyme Disease Diagnosis

Researchers at Columbia University have developed a microfluidic device that can diagnose Lyme disease in as little as 15 minutes. The device is particularly accurate in identifying antibody biomarkers that are present during early stage Lyme disease, raising hopes that it could be useful in detecting cases of early infection in a doctor’s office, leading to timely treatment.

Lyme disease, which is spread by infected ticks, is incredibly common. Approximately 300,000 Americans are diagnosed with the disease each year, and if left untreated it can result in serious neurological and cardiac symptoms. The disease is difficult to spot, as many of the early symptoms are similar to those found with other conditions.

Diagnosing and treating the disease early is important in achieving good patient outcomes, but the current diagnostic tests require both an ELISA and a western blot, which are cumbersome, take a while to perform, and require trained laboratory specialists. Moreover, the accuracy of these tests in identifying early cases of Lyme disease is quite poor.

Zoomed photo of fluid moving through a small channel in the new microfluidic chip.
To address these issues, the Columbia researchers developed a point-of-care microfluidic test for Lyme disease, which a doctor could use in their office, and which can provide a diagnosis within just 15 minutes.

“Our findings are the first to demonstrate that Lyme disease diagnosis can be carried out in a microfluidic format that can provide rapid quantitative results,” said Sam Sia, a researcher involved in the study. “This means that our test could easily be used directly in a doctor’s office, obviating having to send the samples out to a laboratory that needs at least a couple of hours, if not days, to get test results.”

The new assay detects three biomarkers of Lyme disease in patient samples, and demonstrates greater sensitivity than traditional Lyme detection assays. Excitingly, the device also appears to be better at detecting early stage Lyme disease and can detect antibodies that are present in the blood in the first few weeks after someone contracts Lyme disease.

“While the assay will require more refinement and testing before it can be approved for widespread use as a test for Lyme disease, our results are very exciting,” said Siddarth Arumugam, another researcher involved in the study. “It will help so many people if we can develop a single, rapid, multiplexed diagnostic test to identify Lyme disease stage that can be used in doctors’ offices.”

Reference: A Multiplexed Serologic Test for Diagnosis of Lyme Disease for Point-of-Care Use

Wednesday, August 07, 2019

Researchers Use Electrical Signalling to Detect Bacteria

Researchers at the University of Warwick have found bacteria can be detected in minutes by zapping them with electricity.

Scientists at the university in the United Kingdom discovered healthy bacteria cells and those inhibited by antibiotics or UV light show different electric reactions. When zapped with an electrical field, live bacteria absorb dye molecules causing the cells to light up so they can be counted. Bacillus subtilis and E. coli were used as model organisms.

Testing commercial products for bacterial contamination can take days. During this time, they can cause significant numbers of illnesses and infections can become life threatening if not identified and treated appropriately.

The researchers’ findings, published in Proceedings of the National Academy of Sciences of the United States of America, could lead to development of medical devices that can rapidly detect live bacterial cells, evaluate the effects of antibiotics on growing bacteria colonies, or identify different types of bacteria and reveal antibiotic-resistant bacteria. One target is quality control in the water, pharmaceutical, food, and beverage industries.

James Stratford, from the School of Life Sciences and spinout company Cytecom, said “the system we have created can produce results which are similar to the plate counts used in medical and industrial testing but about 20 times faster. This could save many people’s lives and also benefit the economy by detecting contamination in manufacturing processes.”

Scientists showed bioelectrical signals from bacteria can be used to determine if they are alive or dead. The approach uses membrane-potential dynamics and electrical stimulation to differentiate between incapacitated and viable cells.

The team developed an experimental tool to study the relation of bacterial electrical signaling. Using it combined with time-lapse microscopy, they showed live and inhibited cells respond to electrical stimulation in opposite directions. A 2.5-second electrical stimulation caused hyperpolarization in unperturbed cells while inducing depolarization in inhibited cells.

Findings offer an approach for rapid detection of proliferative bacteria without observation of actual proliferation or time-consuming calibrations for bacterial species. It can detect proliferative cells within a minute after electrical stimulation.

Researchers founded a start-up company called Cytecom. The firm has been awarded a grant from Innovate UK, a national funding agency, which means devices could be available to researchers and businesses shortly.

The team combined biological experiments, engineering and mathematical modelling.

“This work demonstrates that bacterial electricity can lead to societally important technology, while at the same time gaining fundamental insights into our basic understanding of cells. The tool we developed can offer more opportunities by allowing experiments which were not possible to perform before,” said Munehiro Asally, assistant professor at the University of Warwick.