Friday, March 28, 2014

Corgenix to Expand Ebola Virus Rapid Testing Capabilities in Sierra Leone

An outbreak of the deadly Ebola virus in West Africa has prompted Corgenix Medical Corporation to extend its existing viral hemorrhagic fever (VHF) rapid test development to include the Ebola virus. Corgenix has already developed and CE marked a rapid test for the Lassa fever virus, another member of the VHF group of viruses.

In collaboration with its research partners from the Viral Hemorrhagic Fever Consortium (VHFC), Corgenix recently completed a multi-year study conducted at the Kenema Government Hospital (KGH) in Kenema, Sierra Leone. The clinical trial investigated the clinical utility of several VHFC diagnostic products, including Corgenix' recently CE marked ReLASV(R) Antigen Rapid Test for Lassa virus. The VHFC is a collaboration of academic and industry members headed by Tulane University and partially funded with support from the National Institutes of Health (NIH).

"This outbreak reinforces the importance of developing and testing a rapid Ebola test," said Robert Garry, Ph.D., Professor of Microbiology and Immunology at the Tulane University School of Medicine and Principal Investigator of the Consortium. "In patients demonstrating fevers, we need the ability to not only screen for Lassa, but also Ebola. The VHFC is expanding on our existing diagnostic testing foundation to advance Ebola testing in the same way we've been successful with the development of the rapid test for the Lassa virus."

The March 2014 Ebola outbreak originated in Guinea, with suspected cases in neighboring Sierra Leone and Liberia. This event has the added consequence of two high mortality VHFs in the same area of West Africa.

"This outbreak clearly demonstrates that Ebola, though rare, is still a major public health problem," said Douglass Simpson, Corgenix President and CEO. "When it does occur, it is deadly, and getting test results back quickly is the key to diagnosing and treating patients and saving lives."

Current Ebola testing requires special biohazard handling, and samples are often sent out of West Africa for processing. This can result in delays of up to several days before diagnosis can be confirmed and treatment started. The Corgenix ReLASV test is a rapid, highly accurate, 15-minute test that detects Lassa virus antigen in blood, leading to early acute-stage treatment, which is key to survival. ReLASV is currently being used on-site at KGH in Sierra Leone for Lassa fever testing and diagnosis.

"We are expanding our rapid testing platform to Ebola with the intention of extending screening to patients using these advanced diagnostics," said Simpson. "Due to the added risk to the population and health care workers, it will be important that health officials have the ability to screen not only for Lassa, but for Ebola, with a rapid test capable of being run in field hospitals in a format that works throughout West Africa."

Suspected cases of either Lassa or Ebola fevers can exhibit similar symptoms, including hemorrhage. Lassa hemorrhagic fever is spread through contact with infected rodents and is estimated to infect 300,000 to 500,000 people per year across the region, with at least 5,000 deaths reported annually. The illness is characterized by bleeding and coagulation abnormalities, with mortality rates reported exceeding 25 percent and reaching 50 percent during epidemics. Ebola hemorrhagic fever can be transmitted to humans through contact with several animal species and is spread among humans through close contact with other infected individuals. Ebola is one of the deadliest viruses on the planet, with mortality rates of between 50 and 90 percent, and it can kill within 10 days to two weeks.

In 2010, Corgenix was awarded an NIH grant to work with Tulane University, The Scripps Research Institute and Autoimmune Technologies for the development of new, rapid diagnostic tests for the Ebola and Marburg viruses. Through this foundational grant and the VHFC partnership that includes Tulane University, Corgenix and its partners plan to continue to develop advanced testing products for Ebola, Marburg and other dangerous hemorrhagic fevers, which are also considered bioterrorism threats. The research includes the development of testing capabilities that would pair Lassa and Ebola rapid detection kits for use in Sierra Leone and other West Africa locations.

VHFC Lassa diagnostic (ReLASV Test Kit) is CE marked for diagnostic use in EU and other international markets. It has not been cleared or approved for diagnostic use in the United States by the FDA. VHFC Ebola products have not yet been cleared or approved for diagnostic use by any worldwide regulatory authority.

The information contained in this press release does not necessarily reflect the position or the policy of the U.S. Government, and no official endorsement should be inferred.

Thursday, March 20, 2014

MIT Develops “Illuminating” Rapid Method for Bacterial Detection

Ever wonder why fruits and vegetables sometimes hit the shelves contaminated by pathogenic bacteria such as listeria, E. coli, and salmonella?

According to Tim Lu, an assistant professor of electrical engineering and biological engineering at MIT, it boils down to the inefficient bacteria-detection assays used in the food industry. In some cases, these aren’t accurate or speedy enough — sometimes taking several days to catch contaminated produce.

But now Lu’s startup, Sample6, is commercializing an advanced assay platform that “lights up” pathogenic bacteria for quick detection, with the ability to detect only a few bacteria.

Based on Lu’s graduate school research at MIT, the assay uses biological particles called bacteriophages, or phages, which only target bacteria. In Sample6’s case the assay is engineered to inject pathogenic bacteria — specifically, listeria — with an enzyme that reprograms the bacteria to shine very brightly.

The illustration above (click on image to zoom in) depicts phages infecting a target bacteria and generating light-emitting proteins as reporters for bacterial contamination (illustration by Yan Liang).

To use the commercial assay, called the Bioillumination Platform, factory workers simply swab samples with a sponge, wait for the phages to do their work, and run the sample through a machine that detects any light emitted. Results can be plugged into the company’s software, which tracks contaminated products and can provide analytics on whether contamination correlates with certain days, people, or suppliers.

The aim is to mitigate the millions of illnesses caused each year by contaminated food in the United States, along with costly recalls for food producers. But the assay’s simplicity should also promote better sanitation practices, Lu says.

“If you can catch something before the end of the day, before you ship it out, and if you can sample more all around, you can be more proactive about sanitation and cut down on losses,” says Lu, who serves on Sample6’s board of directors.

Numerous clients have been using the Bioillumination Platform in trials over the past six months. It is currently undergoing certification, to be followed by wider release.

Rapidity, sensitivity, and specificity

According to Lu, the assay’s innovation comes from its improvement upon three key aspects of bacterial detection: specificity, sensitivity, and rapidity. Other methods — such as immunoassays, cultures, or polymerase chain reactions (PCR, which copies DNA) — may be efficient in one area, but lacking in the other two.

Sample6’s specificity comes from its use of phages, which have specific pathogenic targets: Phages that attack listeria, for instance, won’t attack E. coli. To this end, they can also discriminate between pathogenic bacteria and the potentially thousands of innocuous bacteria nearby.

To achieve better sensitivity, Lu says, the company modifies the production of the bioilluminating enzyme, injected by the phage into the pathogen, to cause the bacteria to shine very brightly, even if only a handful of cells are present.

With this increased specificity and sensitivity, the assay skips the amplification, or culturing, step required in other methods, making it, according to Sample6, the world’s first “enrichment-free pathogen diagnostic system.”

For instance, if one strain of a pathogen needs identification, “producers usually grow the bacteria out to large numbers before they can detect it,” Lu says. “This is slow, and obviously not ideal for the food industry.”

All these improvements contribute to the assay’s speed, Lu says. “Basically, we’re producing enough signal to detect a few specific cells quickly, which gets you really rapid sensors,” he says.

A diagnostic pivot

The assay is used today strictly for detection of bacteria. But it started as a potential therapeutic, when Lu was an MD/PhD student in the MIT-Harvard Health Sciences and Technology program in the mid-2000s.

In a lab at Boston University, Lu engineered phages that could break apart antibiotic-resistant biofilms — coatings where bacteria live and thrive — by injecting bacteria with certain enzymes to make the biofilms self-destruct.

This discovery would earn Lu the $30,000 Lemelson-MIT Student Prize, in 2008, and a spot on Technology Review’s 2010 list of top innovators under 35.

Seeing phages as better antimicrobial treatments than antibiotics — to which biofilms and bacteria can build immunity — Lu, Sample6 co-founder and now vice president of operations Michael Koeris, and other colleagues bootstrapped to commercialize the technology. They funded their company, then called Novophage, through university business-plan competitions across the country, and outfitted nearly an entire lab with reused equipment from MIT and auctions.

Faced with the financial crisis and challenges in commercializing therapeutics, they pivoted to diagnostics. They shopped their phages to bacteria-plagued industries — such as oil and water treatment, where biofilms build up in pipelines — before seeing firsthand that the food industry “was in desperate need of new detection technologies.”

Most food manufacturers were still using traditional assays, Lu says, with some still using pen and paper or spreadsheets to track contamination — “which makes it nearly impossible to gather large amounts of data,” he says.

In an incubator at the University of Massachusetts at Boston, the renamed Sample6 tailored the product for the food industry before relocating to its current headquarters in Boston’s Seaport District, where a 15-person team now works on research and development and small-scale manufacturing. After leading the startup through technological implementation, Lu took a position in 2012 on its board, where he continues advising.

‘Sourcing from nature’ 

Today, Sample6’s assay detects listeria and is used solely by the food industry. But it’s a platform technology, Lu says, that can be used to detect other pathogenic bacteria, such as E. coli and salmonella, and for other means across other industries.

“Phages are the most abundant biological particle on Earth. Since they have coevolved with bacteria for eons, nature provides a rich database of phages which target desired bacteria. Thus, by sourcing from nature, we can adapt the platform to other pathogens and applications,” he says.

The phages could be modified, for instance, to break apart the biofilms that build up and corrode oil pipelines, or to detect the pathogenic bacteria that sometimes cause oil to sour by changing its composition.

The next practical application, however, is most likely in health care, with the potential for clinical diagnostics or rapid detection of contamination in hospital rooms — with the aim of decreasing the 1.7 million cases of hospital-associated infections recorded in the United States each year.

With the assay, Lu says Sample6 hopes to bring synthetic biology, and specifically phages, to microbial detection across many fields. Further down the road, he says, a goal is to transform diagnostics into something more accessible to the public — perhaps even leading to at-home diagnostics.

“Fundamentally, I see this assay as an enabler for many more applications. We want ultimately to democratize the use of synthetic biology in the real world,” he says.

Source: MIT News

Thursday, March 6, 2014

Microarray Detects Plague in Ancient Human Remains

Scientists who study past pandemics, such as the 14th-century Black Death that devastated much of Europe, might soon be turning to an innovative biological detection technology for some extra help.

The apparent first use of this technology, known as a microarray, for studying pathogens from ancient DNA, was reported by a team of scientists in Scientific Reports.

Researchers at McMaster Univ., led by Hendrik Poinar, an assoc. prof. of evolutionary genetics, and Lawrence Livermore National Laboratory (LLNL) tested the application of a novel microarray, the Lawrence Livermore Microbial Detection Array (LLMDA), to identify human bacterial pathogens from archaeological remains. The team tested two samples that had been previously verified as containing pathogens through another technology.

One of the samples, an intestinal substance, showed the presence of cholera and was preserved from a patient who died from the disease during an 1849 outbreak in Philadelphia. The specimen was provided by the Philadelphia-based Mütter Museum.

The other sample tested with the LLMDA indicated the presence of Yersinia pestis (or plague) in a medieval tooth from 1348 from the East Smithfield burial ground in London. An estimated 30 to 50% of the European population succumbed to plague from 1347 to 1351.

Both Poinar and LLNL biologist Crystal Jaing believe that the Lab's LLMDA technology will be tenfold faster and tenfold less expensive than current genomic sequencing as a means of studying pathogens in ancient DNA.

"Microarrays may be a potential alternative solution, as well as a complementary tool, to genomic sequencing for studying ancient DNA," Jaing said. "It offers a faster and cheaper approach to studying complex samples."

Poinar, who is an expert on ancient DNA, agreed.

"We know that most bacterial pathogens likely go undetected in ancient remains due to the overwhelmingly strong contaminant signal from molecules that don't originate in human organs. One way to access this information would be to sequence everything in the sample and analyze it. But this is prohibitively costly and requires a lot of bioinformatics time.

"The LLMDA selectively targets pathogens that are likely to be of interest from an evolutionary standpoint and appears to work well with heavily degraded DNA, typical of most fossil and archival remains, so this is an excellent tool," Poinar continued.

Scientists studying the origins of infectious disease and population health over time normally find that ancient human remains contain highly degraded DNA in which the pathogen represents only a tiny fraction of the total DNA yield.

Ancient pathogen DNA is heavily mixed with other human and environmental DNA. Lengths of these fragments are often as small as 30 to 50 bases compared with regular DNA fragments that are hundreds to thousands of bases long. The amounts of pathogen in the two samples tested with the LLMDA were three ten-thousandths of the total sample for cholera and eight ten-thousandths for Y. pestis.

"We found other pathogens in the chlorea and Y. pestis ancient DNA samples," Jaing said, noting that tetanus was found along with Y. pestis.

Beyond showing the potential for microarrays to become a useful screening tool for archaeological samples, the team's findings demonstrate that the LLMDA can identify primary and/or co-infecting bacterial pathogens in ancient samples.

Developed in early 2008, the LLMDA permits the detection of any virus or bacteria that has been sequenced and included among the instrument's 135,000 probes—on a one-inch wide, three-inch long glass slide—within 24 hrs. The LLMDA version run for the cholera and Y. pestis tests could detect about 1,850 viruses and about 1,400 bacteria.

While the Livermore instrument has previously been used to analyze the purity of infant vaccines, human clinical samples and diseased animals, it had not been deployed to study ancient pathogen DNA until this collaboration.

In Jaing's view, the value of studying ancient human remains for infectious disease is that the research can offer clues as to how past pandemics happened and why they were so deadly.

"By looking at differences between modern DNA and ancient DNA, we may be able to better understand the evolution of diseases and that could help us better understand future disease outbreaks."

She noted that she believes the use of microarrays will speed up the discovery and identification of pathogens from ancient human remains.

"The LLMDA could serve as an excellent screening tool to rapidly identify pathogens. Then genomic sequencing could be used to provide detailed genetic comparison."

Genomic sequencing is the process of determining the precise order of the four different DNA bases—adenine, guanine, cytosine and thymine—within a cell of anything from bacteria to plants to animals.

Two other institutions participated in the research—the College of Physicians of Philadelphia (Mutter Museum) and the Univ. of South Carolina.

"This collaboration has gone very well," Jaing said. "Our groups have complementary skills and expertise. Hendrik's group is a leader in biological archaeology and in analyzing ancient DNA. The LLNL team has expertise in microarrays, pathogen detection and bioinformatics."

In addition to Jaing, other LLNL scientists who worked on the research team were biologists Monica Borucki and James Thissen, along with computer scientists Jonathan Allen, Shea Gardner and Kevin McLoughlin.

During the past several years, LLNL has established collaborations to use its LLMDA with about 30 universities, companies and research centers, including Merck, the Naval Research Medical Center, the Centers for Disease Control and Prevention, Johns Hopkins University and Kansas State University, among others.

Their paper, "Ancient pathogen DNA in archaeological samples detected with microbial detection array," is online at Scientific Reports.

Source: Lawrence Livermore National Laboratory