Tuesday, March 10, 2009

The (Avian and Other) Flu Virus - A Major Medical Development...

A few weeks ago most major news services reported what appears to be a very significant medical breakthrough. I first read about it in the New York Times which stated that according to a study conducted at Dana-Farber Cancer Institute, Harvard Medical School, the Burnham Institute for Medical Research, and the Centers for Disease Control and Prevention (CDC), an experimental treatment made from human proteins neutralized a wide variety of influenza germs, including the H5N1 avian flu, the 1918 pandemic virus and some seasonal forms of the illness. The National Institutes of Health funded the work.

Dr. Ruben Donis, chief of the Molecular Virology and Vaccines Branch at CDC, one of the studies authors, stated that "Our human monoclonal antibody protected mice from the lethal H5N1 virus even when injected three days after infection."

“This is good news, but many antibodies can do this. What surprised us is that the same antibody protected mice from a lethal infection with a very different virus such as the H1N1 subtype that causes seasonal human infections; this is really remarkable."

Dr. Donis declared that "These antibodies have an important therapeutic potential and also pave the way for generation of a different kind of universal vaccine."

If I understand it correctly I believe this is a significant breakthrough because the newly developed antibodies cause changes to the virus that make it unable to attach itself to host cells and these changes seem to occur to not just any one specific strain of virus but to viruses generally. Thus, because it can be effective against various strains of flu it could be more effective as an annual flu shot (allowing plenty of vaccine to be made in advance of flu season without having to see what this year's variation will look like) and it could combat a breakout of a new virulent forms of virus (such as bird flu) thus averting a possible pandemic flu.

I do have a few questions:

1) How is this antibody different in approach from current flu vaccines? Does the current approach not produce those blue things that are shown in the video? If not then how do the current anti body based vaccines work?

2) Was this new treatment discovered by accident or did someone theorize that it might work and then conduct experiments to confirm the hypothesis?

3) What other virus spread diseases could this possibly cure (or is prevent a better word?), if any, and could it possibly cure (or prevent) the common cold?

(Maybe if Doctor Donis sees this he would be kind enough to post an answer to these questions).

Here is the video that explains this medical development (Even though its short (under 2 mins.) I had to watch it a number of times.


11 comments:

  1. It is a useful vedio, helps me more understand about medical development!

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  2. I'm guessing that Dr. Donis' responses would be:
    1) How is this antibody different in approach from current flu vaccines? Does the current approach not produce those blue things that are shown in the video?
    Like the current vaccine, the new approach would also induce antibodies ("blue things"), but these two antibodies are different. The current vaccine directs antibodies to the top of the hemagglutinin, whereas the new vaccine (still under development) would target the bottom part.

    2) Was this new treatment discovered by accident or did someone theorize that it might work and then conduct experiments to confirm the hypothesis?
    My guess is that they had a hunch, but were surprised to get to the finish line sooner than they thought. They did say that a lot more work has to be done, so like the Tour de France, this is just the first stage.

    3) What other virus spread diseases could this possibly cure (or is prevent a better word?), if any, and could it possibly cure (or prevent) the common cold?
    The idea of finding an Achilles heel in viruses to target vaccines and drugs has been around for years, some heels are mor "visible" than others.

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  3. Thank you Anonymous - your answers were very helpful. Its interesting to me how "physical" the work seems. To think about targeting the top part vs the bottom part of something as small as a hemagglutinin is certainly beyond anything imaginable to a non scientist like me. That was a good hunch by the scientists who worked on this - I still do not really really understand why targeting the bottom is different than targeting the top - though I suspect therein may be the "physicality I am referring to - somehow by attaching the antibodies to the bottom the virus is physically prevented from lodging itself in a host cell, whereas if the antibodies attach to the top part then it can? Alternatively - perhaps its that for some reason these more universal antibodies will only attach to the bottom part so its not so much where they attach but the fact that they attach at all? (I imagine for the scientists who do this work the lay public, like me, must seem awfully uninformed - but at least curious is a start. Anyway, thanks again for your thoughtful reply to my three questions - I suspect your responses are exactly right. Thank you amigo.

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  4. Sorry for not telling you that the top of the hemagglutinin is highly variable (thru mutation) from strain to strain while the bottom part remain quite constant (does not mutate).

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  5. This was no accident. If you look closely at the video, you'll see that the hemagglutinin must make a radical shape change to enter the host cell. It basically turns itself inside out. Because form=function in proteins, any mutation would probably make this shape change unworkable and the virus could not fulfill its function. Since the protein is unlikely to mutate, it becomes a stellar target.

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  6. Exactly what I deduced! - The bottom part is stable so no matter how much the top part mutates (mutation = scary) this new vaccine may prevent it from living in the host. Its a a beautiful thing - congratulations to all who worked on this - it must be very rewarding for them to see their work get the attention it deserves and even more importantly to have made such a significant contribution to the field that has such enormous potential. Gracias again Senor Anonymous.

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  7. Thank you for that comment too JEB - "form = function in proteins" - i take it that gets back to my sense that in the molecular level of cell function processes are as much physical as anything else? Given the right physical environment viruses will either invade or not depending on such things as shape and size? It would be neat to make a series of videos like this one that explain important scientific current developments (or even not so current). I really liked this video although form a lay person's perspective another minute or two explaining a few more basics would have made it more intuitive (anyway for me). It would be fun to be on panel to pre publication video reviewers to give feedback to the makers of the videos from the perspective of the interested but uneducated in the field lay person.

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  8. This comment has been removed by the author.

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  9. Germain brings to mind the wonderful Paul de Kruif book, Microbe Hunters. Re-read Microbe Hunters, and remember how far our great scientists have taken us in the understanding and eradication of disease.

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  10. Hi,
    I have a question.
    Is it true that men who are circumsised have less of a chance of getting the HIV virus over those who are not?
    Thanks,
    Pedro

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  11. A really useful video.. thanks for sharing

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