wg48temp9
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Registered: 30-12-2018
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Questions about mRNA vaccine for Coronavirus
So they synthesis a mRNA corresponding to part of the protein outer envelop of a virus. The mRNA is then encapsulated in a vector and injected in to a
person. The mRNA enters cells of the person and causes the cell to synthesise the protein that is part of the viruses envelope which triggers the
immune system of the animal to make antibodies against that part of the virus.
Apparently the vector can be a virus or even a just an emulsion containing the mRNA. Is it that easy to get mRNA into a cell and get the cell to
manufacture the protein and get the cell to export the protein out ?
Presumable the cells continue to make the protein until the mRNA stops working ?
Also presumable the cell will have some of the protein in its envelope and may be attacked by the immune system?
I assume/hope the vaccine will be well tested.
I am wg48 but not on my usual pc hence the temp handle.
Thank goodness for Fleming and the fungi.
Old codger' lives matters, wear a mask and help save them.
Be aware of demagoguery, keep your frontal lobes fully engaged.
I don't know who invented mRNA vaccines but they should get a fancy medal and I hope they made a shed load of money from it.
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Metacelsus
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Location: Boston, MA
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Mood: Double, double, toil and trouble
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Quote: Originally posted by wg48temp9  | So they synthesis a mRNA corresponding to part of the protein outer envelop of a virus. The mRNA is then encapsulated in a vector and injected in to a
person. The mRNA enters cells of the person and causes the cell to synthesise the protein that is part of the viruses envelope which triggers the
immune system of the animal to make antibodies against that part of the virus.
Apparently the vector can be a virus or even a just an emulsion containing the mRNA. Is it that easy to get mRNA into a cell and get the cell to
manufacture the protein and get the cell to export the protein out ?
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Getting mRNA into a cell isn't very efficient, but once it's inside the mRNA will be translated just like any other. And the spike protein naturally
displays itself on the cell surface.
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Presumable the cells continue to make the protein until the mRNA stops working ?
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Yes. mRNA half-life (in the absence of degradation signals) is on the order of ~10 hours. Presumably the vaccine designers will use some tricks (there
are many) to make it more stable.
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Also presumable the cell will have some of the protein in its envelope and may be attacked by the immune system?
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Yes, that's the idea.
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I assume/hope the vaccine will be well tested. |
Yes, this is what clinical trials are for.
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wg48temp9
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Posts: 761
Registered: 30-12-2018
Location: not so United Kingdom
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Its amazing how much we know about the biochemistry of cells and how we can use that knowledge. PCR tests for example or how our immune system
manages to make such a variety of antibodies.
I don't like the idea of having my cells tricked in to making foreign proteins.
However I don't want to get killed by virus so I will be one of the first to line up for the vaccine.
I am wg48 but not on my usual pc hence the temp handle.
Thank goodness for Fleming and the fungi.
Old codger' lives matters, wear a mask and help save them.
Be aware of demagoguery, keep your frontal lobes fully engaged.
I don't know who invented mRNA vaccines but they should get a fancy medal and I hope they made a shed load of money from it.
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DrRadium
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Posts: 16
Registered: 30-11-2021
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| Quote: Originally posted by wg48temp9 | So they synthesis a mRNA corresponding to part of the protein outer envelop of a virus. The mRNA is then encapsulated in a vector and injected in to a
person. The mRNA enters cells of the person and causes the cell to synthesise the protein that is part of the viruses envelope which triggers the
immune system of the animal to make antibodies against that part of the virus.
[snip]
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Even today I think there are two things most people don't know about the mRNA vaccines. First, was how the speed of production helped provide time
for testing. The mRNA component was designed in about a day, and the first of the experimental vaccine itself was ready in a few weeks. And from then
to when they were given emergency approval was all preclinical and clinical testing.
Second, I doubt most people were aware how well developed the basic technology behind the mRNA vaccines was going into the pandemic. I had worked
with a 2nd or 3rd generation lipid (from a kit no less) coating nucleic acids, and injecting the liposomes into brain to induce transient expression
of two proteins (a serotonin receptor and a GFP marker protein) I was using DNA not RNA but it was the same basic idea as the mRNA vaccines. That was
in 1998. The technology was already well developed enough that there were plug and play kits for using it.
Granted I ended up using a viral-based gene transfer vector, the efficiency of liposome mediated expression being at least an order of magnitude lower
than the viral system, which itself wasn't spectacular but it was good enough and persisted longer. The lipids for in vivo lipofection have been
improved greatly, and mRNA vaccines are an almost ideal use for them. As a rule the big problems with trying to induce expression of a transgene via
a gene transfer vector of any kind is the low number of cells affected and brief duration of expression. With a vaccine, you don't have to affect
very many cells to get a good immune response and you want only a brief expression.
[Edited on 2-8-2022 by DrRadium]
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