Seegene and DuPont Nutrition & Health said today that they have inked an agreement to jointly develop highly multiplexed assays to detect foodborne pathogens by combining Seegene's real-time PCR and melt curve analysis technology with DuPont's benchtop BAX System.
The agreement marks Seegene's first initiative in the food safety testing market and, according to a company official, is indicative of a greater effort to move its technology into applied markets. Until now, the company has been focused primarily on developing its assay technologies for human molecular diagnostic applications, making some headway in Europe and Asia, but struggling to gain a foothold in the US.
For DuPont, the deal will add to its arsenal of molecular testing options for food safety. The company has previously licensed various PCR-related technologies from Applied Biosystems (Life Technologies), DxS (Qiagen), Idaho Technology, and Biosearch.
Under the agreement, DuPont and Seegene plan to develop highly multiplexed, real-time PCR assays for the rapid detection and differentiation of 10 or more organisms from a single sample in a single test. Financial terms of the agreement were not disclosed.
Seegene has multiple technologies that are conducive to such highly multiplexed testing. For instance, its dual-priming oligonucleotide, or DPO, technology is designed to generate consistently high specificity by blocking extension of non-specially primed templates and eliminating primer competition.
The company also has a technology called real amplicon detection, or READ, which it claims combines the advantages of multiplex and nested real-time PCR while increasing specificity and sensitivity 10- to 100-fold over other real-time PCR technologies.
Both of these technologies enable a much higher degree of multiplexing than conventional real-time PCR — between 10 and 20 targets as opposed to five or six — but were hampered by a lack of commercial instrumentation with the power to resolve and detect targets at this level of multiplexing.
To address that, Seegene last July launched its TOCE technology, which enables highly multiplexed melt curve analysis on most commercial real-time PCR instruments by enabling identification of multiple targets in a single fluorescent dye channel and providing a consistent Tm value regardless of sequence variation (PCR Insider, 7/21/2011).
Seegene, which is based in Korea but has an office in Rockville, Md., has inked several deals for use of its technologies in the human diagnostics realm, mostly outside the US.
For instance, in April 2011 it said it was partnering with Korea's Samsung Medical Center to co-develop molecular diagnostics for cancer using the DPO and READ technologies (PCR Insider, 4/7/2011); in May 2011 it announced a partnership with Akonni Biosystems to combine that company's TruArray gel-drop array technology with the DPO method for simultaneous detection of multiple respiratory pathogens (PCR Insider, 5/12/2011). In addition, UK-based clinical diagnostics firm Randox disclosed in March that it has been working closely with Seegene since 2009 to integrate its assay technologies into commercial molecular diagnostic panels for respiratory pathogens, sexually transmitted diseases, and KRAS/BRAF/PIK3CA mutations (PCR Insider, 3/1/2012).
In addition, Seegene markets several molecular diagnostic tests using its various technologies outside the US, including tests for various influenza strains in Europe and Asia; a test for multiple diarrhea-causing viral agents in Canada; a multi-pathogen screening test that can identify more than 90 top sepsis-causing pathogens; a test for simultaneously detecting tuberculosis and genetic mutations for multi-drug-resistant TB; and multiplexed detection panels for respiratory viruses and STDs. However, the company has not secured US Food and Drug Administration approval for any of its assays.
Dave Dolinger, vice president of business development at Seegene, told PCR Insider this week that Seegene's key strength is inventing and developing "new technologies that are pushing forward molecular testing more than diagnostics."
"At one point … we were really looking at trying to make it as a diagnostics company," he said. "But if you really want to make it, you can't make it just on the assays. You really need that whole integrated system approach, where you have both instrumentation … as well as that broad menu of tests.
"So it really is almost a refocus by the CEO [Jong-Yoon Chun] and identifying ourselves more as a technology company," Dolinger added. "We have the ability to design, develop, and manufacture for people, but we're looking now at how we can get these technologies out there."
Dolinger noted that the company is still heavily involved in partnering with others on human molecular diagnostic development, though.
"We think that the biggest impact truly will be in human clinical diagnostics," Dolinger said. "But we think that this kind of technology actually can take a deeper hold faster in other areas of molecular testing. You don't have to jump through the same regulatory hurdles. So you can actually get traction very quickly and see major changes in the way testing is done."
In foodborne pathogen detecting, testing is typically done one target or a few targets at a time. If its collaboration with Seegene is fruitful, DuPont will look to provide a test to detect at least 10 organisms in a single run.
"Typically you can have one target per dye channel," George Tice, research and development director for DuPont Qualicon Diagnostics, told PCR Insider. "If you're using a [molecular beacon], or TaqMan, or Scorpions [probe], you usually associate one of those probes with a target. So if you have five channels, you can detect up to five targets. For us, and many folks, they have a reference dye that takes up one channel, and then have an internal control that takes up another channel. So that leaves you with maybe three or four different channels for the targets of interest."
Tice said that Seegene's TOCE technology allows you to detect "multiple targets within a dye channel, which increases the amount of multiplexing that you can accomplish. Also, the unique [DPO] priming technology adds specificity to the priming event, which also helps with the multiplexing efficiency."
DuPont and Seegene will design the assays for use on DuPont's BAX System, an automated, benchtop PCR-based detection system DuPont developed in collaboration with Applied Biosystems before it was acquired by Life Technologies. DuPont Qualicon, a business unit with the DuPont Nutrition & Health division, began selling the BAX System in the mid 1990s, but has upgraded the platform in recent years to be able to detect multiple targets in each well with faster processing and real-time PCR capabilities (PCR Insider, 8/5/2010).
The US Department of Agriculture currently uses DuPont's BAX-based tests for E. coli O157:H7, Listeria monocytogenes, and Salmonella. In addition, DuPont Qualicon sells its tests to various undisclosed food companies and to third-party service labs that offer testing services to food companies. Further, DuPont currently has a collaboration in place with USDA to develop add-on tests for six emerging Shiga toxin-producing E. coli, or STEC, strains.
Tice said that all of these tests are good examples of assays that could be improved through multiplexing with Seegene's technologies.
"To cast a wider net for the non-O157 STECs … you have to screen for virulence factors, you have to screen for seven top serogroups, so now you're probably close to 10 targets that you're looking for," he said. "So there is the possibility that you could put that into a single test."
In addition, "we have a test that screens for the genus Salmonella," Tice added. "We can tell you that you have Salmonella in your sample, but depending on the market, there is also an interest in whether it's Salmonella enteritidis, or [one of] 10, 12, or 15 different serovars."
DuPont has also over the years entered into agreements with various assay and reagent providers allowing it to develop its multitude of food pathogen tests. In addition to having originally licensed TaqMan technology from Applied Biosystems/Life Tech and Scorpions probe technology from DxS/Qiagen, the company in August 2010 licensed reagents and methods related to SYBR Green I and post-PCR melt curve analysis from Idaho Technology (PCR Insider, 8/5/2010); and in October 2010 licensed IP covering Black Hole Quencher, CAL Fluor, and Quasar dye technologies from Biosearch (PCR Insider, 10/28/2010).
The Seegene technologies constitute "another tool in the toolbox, and it really doesn't incorporate [any of the aforementioned technologies]," Tice said.