Virus-Like Particles May Mean Speedier Flu Vaccines

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.

Comments

Flu !DNA

[Red Flayer]

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.

Bonk bonk on the head

[Tablizer]

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:I'm surprisde no one's done this before

[ColdWetDog]

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.

Re:I wonder...

[crmarvin42]

This solution would probably require much higher doses than current vaccines do, but it would probably be safer and faster.

The flu at least is an RNA virus, but the function of the genetic material is for the replication of the virus after it has infected a cell. When it is not actively infecting a cell the DNA/RNA is completely dormant within the viral coat, thus the debate over whether viruses are alive or not. There is no metabolic activity in the absense of a host cell to infect.

The shell or viral coat is primarily what the immune system recognizes when fighting a viral infection. That is why killed vaccines work. They don't work as well as modified live vaccines (generally) because you don't get the first couple of generations of viral replication (at a slower rate than the wildtype virus) that trigger a much stronger immune response. Viral RNA can also trigger immune response, but the RNA needs to be processed by an antigen presenting cell such as an infected cell or a phagocyte.

It actually works the same way with certain bacteria. Researchers will frequently inject LPS (lipopolysaccharide) into animals to simulate a bacterial infection, because bacteria have LPS on their surfaces and their are immune systems designed to recognize this ubiquitious bacterial component.

I'm not sure about separate shells, but I do know that many (all?) viruses have several different proteins involved in making the shell, and that changes in which proteins are present will change the antigenic profile of the virus.