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Biotech Medicine Science

Virus-Like Particles May Mean Speedier Flu Vaccines 80

Posted by kdawson from the just-the-dna-ma'am dept.
We've been talking a lot lately about flu vaccines. Now an anonymous reader sends us to a Technology Review piece on two human trials involving so-called virus-like particle vaccines, which promise to be much faster to churn out than traditional vaccines. (Here's a single-page version but without the useful illustration.) VLP vaccines use a protein shell, grown in either plant or insect cells, that look just like real viruses to the body's immune system but that contain no influenza RNA genetic material. A company called Medicago grows its VLPs in transgenic tobacco plants, while another called Novavax uses "immortalized" cells taken from caterpillars. Providing they pass safety muster, both techniques should be able to produce an influenza vaccine more quickly than current methods, using just the DNA of the virus.
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Virus-Like Particles May Mean Speedier Flu Vaccines More

Virus-Like Particles May Mean Speedier Flu Vaccines

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  • Flu !DNA (Score:4, Insightful)

    by Red Flayer ( 890720 ) on Friday October 23, 2009 @11:17AM (#29846387) Journal

    Providing they pass safety muster, both techniques should be able to produce an influenza vaccine more quickly than current methods, using just the DNA of the virus.

    Sorry to nitpick, but influenza is an RNA virus, not a DNA virus.

    I have no clue if this makes a difference in how quickly a vaccine could be made using this technique, but I just needed to get the "Friday Pedantry" out of the way.

    • Re: (Score:2, Interesting)

      by sumthinboutjesus ( 984845 )
      Good catch on the RNA vs. DNA. However, this would not effect how quickly a vaccine could be made with this technique nor its efficacy, as it is just training the plasma cells to recognize a folded conformation and produce antibodies to bind that 3d conformation, allowing the immune system to clear it after the virus is bound (opsonized).
      • This actually could affect the speed of how quickly the vaccine is made, as more work would be need to done to get the viral genomic information from an RNA virus into a form that could be stably transfected into a cell. Most expression vectors would require a complementary DNA expression cassette for the genome of RNA viruses, which would need to be generated in a lab. Admittedly this would not add on a large amount of time, but still more time would be needed to make a vaccine from an RNA virus versus a D

        • Re: (Score:3, Informative)

          by RDW ( 41497 )

          For standard flu vaccines, the speed of production depends on quite a few steps, some of which can be carried out in parallel (e.g. clinical trials can start before all batches are made), while others need to be done in series (e.g. bulk production can't start until growth conditions are optimised):

          http://www.who.int/csr/disease/swineflu/notes/h1n1_vaccine_20090806/en/index.html [who.int]

          One advantage of the VLP approach is that you can produce the relevant proteins in standard biotech 'factory' organisms, which avoi

        • Just use some reverse transcriptase--it's super fast! I'd imagine that would add a trivial amount of time relative to processing time necessary to produce and collect these VLPs in sufficient quantities to bring a vaccine to market. Perhaps that's what you had in mind.

          • No, I meant that the reverse transcriptase process is an extra step that adds time. I agree that this amount of time may be short, but certainly not trivial. Compared to a DNA virus extra steps, and therefore time, is still required when generating the initial expression vector for an RNA virus. Since we are considering the amount of time it takes to generate a new vaccine for a new strain of flu (and not the generation of additional VLPs from cassettes already incorporated into an expression vector), any
    • Don't feel bad; I came here to say the exact same thing.

    • Re: (Score:2, Informative)

      by Anonymous Coward

      Although influenza is an RNA virus, researchers are probably generating a cDNA library of the flu structural proteins and using these DNA templates to transfect their cellular expression systems, resulting in the production of the virus-like particles. This may be the source of confusion in the summary above.

      • You may be an AC, but you are correct. It is fairly simple to create cDNA librarys of the viral RNA genome. One benefit of cDNA libararies over working with the viral RNA directly is stability. You still need to be fanatical about avoiding contamination of your samples, but DNA is more stable.

    • Re: (Score:1)

      by Jon-1 ( 470969 )

      While you're correct in your analysis of the statement, you're incorrect in regards to the technology. Yes, flu is an RNA virus but the manipulations of the genes that are expressed on the VLP - is all done with DNA. I'm guessing they clone the gene into their expression platform and the cell lines do all the work to put it together.

      Now the big challenge is to prevent the patient from developing anit-vector immunity so that they can use the VLP delivery system again against different targets.

      • Most(all?) viral enveloppes are self assembling and do not need to be hybridised with the vector on a protein level. You just have to make sure your env proteins are expressed trough the vector, so you end up with infected cells bursting with empty shells (as not viral content is produced). You could still have some vector particles in the raw yield, but you need to purify it anyway. Lastly, what negative effects would you expect from an immune reaction to either a plant or insect virus? On the contrary, mo

  • As a future healthcare provider, I certainly hope that vaccines like these will be proven safe and effective. Their promise lies in the ability for the production of vaccines against the dominant strains in a much quicker manner. If we had these methods approved for the current flu season, the industry wouldn't have been caught with its pants down when the H1N1 strain became dominant and hit much more quickly than planned. The vaccines were targeted to be ready for about a month or two from now, and the
    • Agreed, but there are some barriers in the way of ever getting this type of vaccine approved. Most likely these virus-like particles are being expressed by some sort of transformed (cancerous) cell line. Given that this is so, there are some safety issues involved with injecting test subjects with potentially carcinogenic material. They will likely need to find a new way of expressing these particles if they ever hope to use them clinically.

  • A company called Medicago grows its VLPs in transgenic tobacco plants...

    So tomorrow's vaccines can be administered by cigarette?

    • Re: (Score:2, Funny)

      by Tablizer ( 95088 )

      So tomorrow's vaccines can be administered by cigarette?

      The tobacco industry must be just jizzing about this.

      WARNING: The Surgeon General has determined that NOT smoking this pack of Joe Camel the Flu Slayer(TM) may be hazardous to your health.

  • since antibodies react to proteins or other structures and not the RNA/DNA. Maybe profits on vaccines aren't really there?

    • Re: (Score:2)

      by foobsr ( 693224 )
      Maybe profits on vaccines aren't really there?

      At least, 'investors' think so, resulting in rising stock prices [timesonline.co.uk].

      CC.

    • Re:I'm surprisde no one's done this before (Score:4, Insightful)

      by ColdWetDog ( 752185 ) on Friday October 23, 2009 @11:45AM (#29846693) Homepage

      since antibodies react to proteins or other structures and not the RNA/DNA. Maybe profits on vaccines aren't really there?

      Or, alternatively, they've been trying for a long time without success. FTFA:

      VLPs have been an around-the-corner promise for over 20 years. But they've now reached a stage at which even disinterested observers believe, as Columbia University virologist Vincent Racaniello put it, that VLP vaccines "really seem to be coming into their own."

      But don't roll up your sleeve just yet. Sounds a lot like holographic storage, Duke Nukem Forever, better batteries, flying cars, jet packs, sensible women.

  • Bonk bonk on the head (Score:4, Funny)

    by Tablizer ( 95088 ) on Friday October 23, 2009 @11:23AM (#29846459) Journal

    I explained traditional vaccines like this to my kids: "What they do is get some of bad viruses, we'll call them little monsters. So they clone these monsters (kids learn what cloning is from cartoons) and then bonk them in the head to make them all dizzy. Then they send these dizzy monsters into the village, which is your body. The villagers see the monsters and beat the Cheerios out of them, and then kick them out of the city. They also learn to recognize the monsters. So when the real monsters come, the ones that are not dizzy, the villagers know how to recognize them because they look just like the dizzy ones. That's how they know to find the monsters and kick them out."

    Kid: "But daddy, why don't they just put up a Wanted poster?"

    Me: "Uh, go ask your mom."
         

    • Re: (Score:3, Funny)

      by CheeseTroll ( 696413 )

      Are you a Nintendo game designer, by any chance?

    • Re: (Score:3, Interesting)

      by geekoid ( 135745 )

      Funnny, but what the kid asks uis actually closer to how a vaccine works.

      A dizzy monster might recover and go rampaging through the village. The flu vaccine is not a live virrus and as such it is like putting a wanted poster up.

      • Re: (Score:1)

        by Tablizer ( 95088 )

        Zombie monsters with lobotomies? Hey, stop messin' up my analogies with exceptions and bug reports! I bet you were a boring kid ;-)

      • Re: (Score:2)

        by Aladrin ( 926209 )

        The flu vaccine can cause the flu. A wanted poster cannot rob a house.

      • Re: (Score:3, Informative)

        by mikael ( 484 )

        The nasal spray version of the vaccine does contain live virus, but "attenuated" so that it can only reproduce in the lining of the nose.

        • Re: (Score:2)

          by nietsch ( 112711 )

          The lining of the nose (and the upper airways) is where the flu can only reproduce anyway, so that statement is not very comforting. 'Contains no virus' is much safer than contains attenuated virus.

          • Re: (Score:2)

            by mikael ( 484 )

            FluMist [drugs.com]

            Important information about FluMist
            FluMist is a "live virus" vaccine. Influenza virus vaccine is also available in an injectable form, which is a "killed virus" vaccine. This medication guide addresses only the nasal spray form of this vaccine.

            For at least 21 days after receiving FluMist, avoid close contact with anyone who has a weak immune system caused by disease (such as cancer, HIV, or AIDS), or by certain medicines such as steroids, cancer chemotherapy, or radiation treatment. A person with a w

    • Re: (Score:2, Interesting)

      by Schickeneder ( 1454639 )

      They do put up wanted posters. They're known as major histocompatibility complexes!

      http://en.wikipedia.org/wiki/Major_histocompatibility_complex [wikipedia.org]

    • I'm dying to hear your explanation of the "birds and the bees..."

      • Re: (Score:1)

        by Tablizer ( 95088 )

        I'm dying to hear your explanation of the "birds and the bees..."

        You'll have to order my book series: "Educational Guides for Dysfunctional Families".

  • Is this how the Umbrella corp got their start in creating a Zombie virus?

    Hopefully these researchers have created a decent underground lab, with flooded rooms, insane computers, dogs ready to be zombiefied, lots of corridors, exotic weapons with ammo dropped in numerous random places, and other useful stuff. If I was building a virus lab, I'd definately need to have all this available in case someone needs to sneak in and blow it up.

    • You know for an ultra modern state of the art lab they sure have some crapy underground infrastructure and why do these places always still use steam heating?? Which brings up another question. Why do space craft in movies use steam heat?

      • because steam looks cool on camera.

      • Re: (Score:2)

        by ae1294 ( 1547521 )

        Why do space craft in movies use steam heat?

        Space craft have heat exchangers on there fission reactor coolant pipes. It's a cheap way to heat your ship and provides a good home for alien parasites.

        • Yes but that just creates a corrosion problem waiting to happen and in space to boot. Not to mention a major safety hazard, a pressurized steam one not nuclear (insert evil music here). Besides electric heat would be much cheaper over the life of the vessel.

          • Re: (Score:2)

            by ae1294 ( 1547521 )

            Yes but that just creates a corrosion problem waiting to happen. Not to mention a major safety hazard, a pressurized steam

            Just don't have your space craft built by the lowest bidder and make sure they use only non corrosive piping.
            With the proper safety valves and controls steam is perfectly safe. Why waste power making heat when you could be using it for your ion drive or shielding...

            Now if you wanna make a war ship on the other hand yes you might wanna think about it more carefully...

      • Al least they have moved away from steering by using a wheel from a boat. Newer ones use two levers that you have to operate in opposition (lift one up while you pull the other down).
        Using steam doesn't seem so dumb after looking at their steering options, but I kinda wonder how hard it is to shovel coal into the boilers while under zero G's.

        • Re: (Score:2)

          by ae1294 ( 1547521 )

          I kinda wonder how hard it is to shovel coal into the boilers while under zero G's.

          My race doesn't use coal to power our ships... we use the souls of human children and they are very easy to handle or so merlock the soul smith tells me...

  • C'mon folks, did nobody watch I Am Legend?

    • No? (Score:2)

      by nietsch ( 112711 )

      No, i did not watch this 'I am legend' thing you talk about. What is it, a painting or something?

  • http://www.hss.caltech.edu/~camerer/Ec101/JudgementUncertainty.pdf [caltech.edu]

    Tversky, A. & Kahneman, D. (1974). Judgment under uncertainty: Heuristics and biases. Science, 185, 1124-1130

    CC.
  • Antigen Express is working on a synthetic flu vaccine that doesn't use tobacco or caterpillars:

    http://www.masshightech.com/blog/2009/09/25/antigen-express-synthetic-h1n1-flu-vaccine-in-the-works/ [masshightech.com]

  • How many patents on this thing again? I guess the developping countries arent' gonna get it before a while without paying these lab's taxes.

  • production in insect cells has advantages (Score:3, Interesting)

    by airuck ( 300354 ) on Friday October 23, 2009 @12:50PM (#29847533)

    One great advantage in using insect cell lines is that they do not require serum to grow, which is both costly and open to the risk of transmitting zoonotic pathogens. Insect cells can also be more robust than mammalian cells in large scale fermentation conditions.

  • I've done some IT contracting work for Medicago for a few years, they're a local enterprise, and I know the people behind the technology and I know their installations quite well. It's quite impressive, and I know they're now set on human testing after years of work and animal tests. Glad to see them getting some attention. I think this kind of technology is the future of medicine production.

  • Where's the "What could possibly go wrong?" tag?
  • If they release the particles under the GPL, would that square their viral properties or just double them?

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