Bench Press

In order to deal with the global outbreak of swine flu effectively, tracking the number of swine flu cases is imperative. Having as much accurate data as possible regarding the epidemic is essential for evaluating what moves the global community ought to start taking to make it through this outbreak. Thus, using quick and accurate tools to evaluate the countless samples  being collected around the world is an absolute necessity. Luckily scientists at the University of Colorado and InDevR, a small biotech in Colorado, may have exactly what the world needs in a microarray chip dubbed the FluChip.

In 2005 Dr. Kathy Rowlen, CEO of InDevR, led a team at the University of Colorado working with the Centers for Disease Control and Prevention (CDC) in developing the FluChip in order to allow labs across the world to quickly distinguish samples between 72 different influenza strains. Her group’s work produced a viable testing platform that produced results in less than 12 hours with impressive accuracy.

Now Dr. Kathy Rowlen and InDevR have licensed the FluChip technology from the University of Colorado. InDevR has arranged to begin testing samples of the swine flu on a M-gene variant of the FluChip while also working on improving the initial design by incorporating new technologies, hopefully making a new assay basic enough that any lab with PCR capabilities will be able to utilize it. Here’s to hoping the FluChip will help us get a better picture of the current state of the swine flu epidemic.

InDevR Press Release:

InDevR, a small biotech company in Boulder, CO, announced today that they have licensed the FluChip technology from the University of Colorado.  The FluChip was invented by a joint team of scientists at the University of Colorado and the Centers for Disease Control and Prevention in an NIH sponsored effort led by Professor Kathy Rowlen.  Rowlen, now the CEO of InDevR, said that InDevR has arranged to test genetic material from the recent swine H1N1 virus on the MChip as well as other versions of the FluChip which are under development.  According to Rowlen “Based on work we conducted a couple of years ago, it appears that the M-gene version of the FluChip will be able to distinguish human H1N1 viruses from the new swine H1N1 virus.  If that proves to be the case, the FluChip will be a much needed and powerful new tool for surveillance since all of the current influenza diagnostics on the market are unable to subtype this virus.” The most popular diagnostic tests for influenza include rapid immunoassays, which are only able to identify the type (A or B) of influenza virus, and reverse-transcriptase polymerase chain reaction assays, which were designed for human-adapted influenza viruses and are not able to identify the swine H1N1 subtype.  State Public Health Laboratories must now send any influenza A viruses that cannot be subtyped using existing diagnostics to the CDC for analysis by genome sequencing or viral isolation.  The CDC must select viruses to analyze since it is not possible to run every sample collected from a large number of Public Health Labs.

The M-gene based FluChip has been demonstrated to delineate human-adapted viruses from non-human viruses, such as the H1N1 virus that caused the 1918 “Spanish Flu”.  “Since the FluChip assay can be conducted within a single day it could be employed in State Public Health Laboratories to greatly enhance influenza surveillance and our ability to track the virus,” Rowlen said.  InDevR will combine the FluChip technology with an innovative detection technology (NESATM), which InDevR also licensed from the University of Colorado and further developed with NIH sponsorship, to make the FluChip assay inexpensive and easy to use in any lab that has basic PCR capabilities.  “Kathy and her team have been engaged with this and similar diagnostic technology for many years,” said Mary Tapolsky, Senior Licensing Manager at the University of Colorado Technology Transfer Office. “CU TTO is excited about this experienced and motivated group developing and commercializing this promising technology.

Today modern medicine provides patients with numerous drugs for an enormous number of health issues. For example, getting relief from a headache can be as simple as popping open a bottle of aspirin and swallowing a couple pills. While to the patient the delivery of the drug begins and ends with swallowing those two pills with a glass of water, to the scientists working on the drug that’s simply the beginning of numerous steps that hopefully result in a drug surviving the trip through the body to it’s intended target and doing it’s job.

Drugs are therefore designed not just to solve a problem but to survive the human body’s natural mechanisms. The gauntlet of obstacles that a drug faces upon entry into the body is a major reason why many researchers continue to look into innovative techniques for delivering pharmaceuticals.

That’s where research being conducted by Drs. Stefan Franzen and Steve Lommel comes in. Working with the red clover necrotic mosaic virus (RCNMV), Drs. Franzen and Lommel have developed a potential revolutionary drug delivery platform.

Figure 1. Production of Drug Vector

Drs. Franzen and Lommel take advantage of a 17 nanometer space within the 38 nanometer icosahedral capsid of RCNMV in order to store therapeutics. The RCNMV infused with the drugs could then be used to deliver the drugs in a cell specific manner with the addition of targeting peptides.

The preparation of the drug carrying virus is elegant in it’s simplicity and produces a robust delivery mechanism (See Fig 1). First RCNMV is treated with EDTA to open pores in the capsid. Next therapeutics are infused through these open pores. The pores are then sealed with Ca²⁺ which is key in releasing the drug later upon viral entry to the cell. The prepared virus can then be purified via dialysis followed by adding target specific peptides.

The elegance of using Ca²⁺ to seal the pores lies in the fact that the human bloodstream is abundant in calcium. Inside cells, calcium levels are much lower, allowing the pores to open up thereby delivering the infused therapeutics only when the target cell has been entered.

In vitro work with Doxorubicin, a cancer drug, infused RCNMV shows promising results (see Fig 2.) promoting apoptosis only when provided with targeting peptides allowing the drug to be delivered to the interior of cells.

Figure 2. Delivery of Doxorubicin RCNMV to HeLa cells

A potential application of this research is in cancer treatment. Current chemotherapy treatments often result in dramatic side effects as the drugs do not distinguish between diseased and healthy cells. While these results are probably still years from resulting in a commercial therapy it provides hope that in the near future doctors will be able to prescribe chemotherapy treatments with dramatically reduced side effects thanks to target specific delivery of the drugs.

(Sources: NCSU – results. , NCSU News , Franzen Presentation – Plant Virus Nanotechnology)

My favorite character on Star Trek Voyager is “the Doctor” (pictured on the left and portrayed by the very talented Robert Picardo), who despite being “merely” a computer program was able to diagnose and treat nearly any medical ailment. The best part about him was that, because he was “merely” a hologram, he was portable and able to travel through the harshest environments and across any terrain.

While I’m pretty sure we still have years to go before we start being treated by medical holograms with Robert Picardo’s sense of style and humor, the portability of diagnosis is something which we may have just taken one large step closer towards. Christine Keating’s group at Pennsylvania State University has just developed what I’ve dubbed a “Doctor-on-a-Chip” (or DoC, after all system-on-a-chip’s are called SoCs by the semiconductor industry) which have the capability to detect any number of viral pathogens on a single computer chip.

Keating and her colleagues developed a means of coating a chip with nanowires (small wires 8 micrometers long and 300 nanometers in diameter) coated with DNA strands complementary to viral genomes (so that they will bind to viral DNA/RNA if given a chance). But, instead of haphazardly coating the chip, Keating’s group was able to develop a precise, targeted method, employing electrical fields to position the nanowires to exactly where the researchers wanted them (here’s a video showing how the method works).

The picture to the left is almost kind of eerie to me in its precision, much like one would expect on a chip fabbed by Intel or IBM (or Affymetrix) which uses photolithography rather than through electrophoresis.

Impressive to say the least, but the big question remained – does it work? To test this, Keating’s group incubated the chip with suspensions of fluorescently tagged viral DNA fragments complementary to the DNA strands on the nanowires, removed the suspension, and then subjected the chip to fluorescence. What would the result be? Would one see fluorescence organized neatly in the same rows that the nanowires were deposited? Or would there be diffuse or no fluorescence, suggesting nothing at all?

See for yourself:

So, do we have a DoC in the making? Jury’s still out – as we have yet to see if this method can be scaled up, or if its even applicable in a medical setting where time is short, accuracy needs to be very high, and the ability to run controlled samples (e.g. long DNA binding period with perfect fluorescently-labeled viral DNA fragments) is hindered. But, the Keating group is already hard at work creating electrical leads which will enable a faster (and potentially more quantitative) read process for detection.

And who knows, in a few years, this may end up looking like Robert Picardo.

(Image source – Doctor) (remainder of images come from Penn State University public image archive)

Morrow, T. Li, M. Kim, J. Mayer, T. Keating, C; Programmed Assembly of DNA-Coated Nanowire Devices; Science 16 January 2009: Vol. 323. no. 5912, p. 352 DOI: 10.1126/science.1165921