Comments on: Influenza virus-like particle vaccine

By: Headless HA: Universal influenza vaccine?

Headless HA: Universal influenza vaccine? — Thu, 27 May 2010 20:15:37 +0000

[...] mice were immunized first with plasmid DNA encoding the truncated protein, and then with virus-like particles bearing the headless HA. When mice were immunized with headless HA from a 1934 H1N1 strain, all [...]

By: H1N1: Fact or Fiction? « Truth11

H1N1: Fact or Fiction? « Truth11 — Sun, 15 Nov 2009 17:07:04 +0000

[...] 22 Racanietto V. Virology Blog. Influenza virus-like particle vaccine. August 19, 2009. http://www.virology.ws/2009/08/19/influenza-virus-like-particle-vaccine/ [...]

By: Influenza virus-like particle vaccine virology

Influenza virus-like particle vaccine virology — Sat, 12 Sep 2009 05:45:53 +0000

[...] Read the original: Influenza virus-like particle vaccine [...]

By: Technicalbuy

Technicalbuy — Fri, 04 Sep 2009 02:49:25 +0000

Yes I've seen the process in action…incredibly simple. Didn't even mention the surge capacity benefits of plants vs cell culture etc. Wouldn't mind reading your review if you have it handy

By: Technicalbuy

Technicalbuy — Thu, 03 Sep 2009 19:49:25 +0000

Yes I've seen the process in action…incredibly simple. Didn't even mention the surge capacity benefits of plants vs cell culture etc. Wouldn't mind reading your review if you have it handy

By: Ed Rybicki

Ed Rybicki — Thu, 03 Sep 2009 11:19:54 +0000

Yes, well, I could paste my recent review in here…(shameless self-advertising B-) – but I won't.

Suffice it to say that conventional vaccine production requires LARGE amounts of stainless steel and sterile manufacturing conditions just to produce the raw material – and production of the raw material for a plant-produced vaccine does not. My lab has made equivalent products – virus-like particles composed of Human papillomavirus L1 proteins – via baculovirus/insect cell culture, and via transgenic and transient expression in plants, and I can vouch for it costing a LOT less for the infrastructure to produce the plants than it did for all the insect cell culture facilities and media.

And “simply harvesting VLPs from culture medium” requires filtration, centrifuges possibly, columns…which is exactly what the downstream processing for a plant-produced vaccine would need.

Interesting thing about the Medicago HA proteins, and the ones that we have experimented with: they localise to the apoplastic space in leaves – which can be flushed out in intact leaves infused with simple buffer by vacuum infiltration, by low-speed centrifugation without damaging the leaves. You end up with some straw-coloured liquid rich in HA protein, with VERY few contaminants. Pretty much equivalent to harvesting TC SN!

By: Technicalbuy

Technicalbuy — Wed, 02 Sep 2009 03:10:18 +0000

Oh and I forgot that they were the first in the world to produce the H1N1 vaccine. Took them 2wks

By: Technicalbuy

Technicalbuy — Wed, 02 Sep 2009 03:07:06 +0000

Medicago does just that with tobacco plants. 1 square meter of the plants can produce about 30,000 doses of vaccine at under $0.20/dose. It's shown full protection at very low doses and also cross protection with different H5N1 strains. http://www.medicago.com/Theme/Medicago/files/do...

By: profvrr

profvrr — Thu, 27 Aug 2009 15:16:25 +0000

Would it really be easier to homogenize tons of plant leaves to make suitable amounts of vaccine? Isn't simply harvesting VLPs from the cell culture medium far easier from a production standpoint? Someone with production savvy should weigh in on this…

By: profvrr

profvrr — Thu, 27 Aug 2009 02:58:59 +0000

Thanks Ed. Arguing is always welcome here. You are absolutely right about HBV.

By: edrybicki

edrybicki — Wed, 26 Aug 2009 16:04:32 +0000

Ummmmmm….hate to argue, but in HBV infections, virus-like and genome-free 22 nm particles way outnumber the “Dane particles” which are the infectious virions – and were the basis of vaccines made from human serum before recombinant subunit vaccines became the norm?

By: edrybicki

edrybicki — Wed, 26 Aug 2009 15:59:14 +0000

It is therefore very interesting that plant-made H5 HA (and H1, thought is is not published) also buds to form particles, which are more immunogenic than purified HA protein ((D'Aoust et al., Plant Biotechnol J. 2008 Dec;6(9):930-40).

And MUCH cheaper to make than any other way….

By: guenter stertenbrink

guenter stertenbrink — Sat, 22 Aug 2009 14:36:02 +0000

viruses dying naturally, from heat or UV or chemicals – aren't they
also somehow virus-like particles and thus give some immunity
without infecting ?

flumist is better for children, but worse for adults, I had read

By: profvrr

profvrr — Fri, 21 Aug 2009 22:58:22 +0000

Got your email to TWiV, Russ. Great story which we'll cover next week.
Thanks very much.

By: profvrr

profvrr — Fri, 21 Aug 2009 22:58:20 +0000

While 'empty' virus particles – lacking a viral genome – are probably
produced in all virus infections, they are the vast minority. In this
study, the authors specifically engineered viruses that lack the
genome. I don't believe such 'empty' particles play a role in defense
against natural infections.

By: mdubuque

mdubuque — Fri, 21 Aug 2009 14:49:20 +0000

Perhaps my question is caused by a failure to understand this posting.

Is it possible that these types of virus particles are produced by cells as part of a yet undiscovered subsequent strategy for immunizing and defending ourselves against the larger virus particles?

Alternatively stated, we know that some of these virus particles are immunogenic. Is it possible that our immune systems are capitalizing on this capacity via unknown pathways?

By: Russ

Russ — Wed, 19 Aug 2009 18:19:41 +0000

I came across an interesting article related to this post. It is about a vaccine production for Norwalk virus using "virus-like" nanoparticles in tobacco plants. I sent you an e-mail to TWIV and have posted the link here as well.

http://esciencenews.com/articles/2009/08/18/tob...

Russ