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two of the vaccines we have for covin 19
have the distinction of being the first
mrna vaccines to see widespread use in
humans
it's a vaccine technology that uses a
type of molecule called
rna to teach our cells how to resist
disease
so how do they work and how are they
different from the litany of
immunizations you probably got as a kid
let's take a look
all vaccines do one basic thing they
imitate a disease-causing agent
or pathogen with the goal of routing it
out to your immune system then
your immune system knows what to do if
the pathogen ever shows up
mrna vaccines do that too but they
represent a departure from the way we've
introduced pathogens in the past
most of the time we've used a bit of the
real thing like
killed pathogens or living ones that
have been weakened or just
pieces of them or even substances that
bacteria
just make in any case these bits our
immune system can spot
are called antigens each antigen has a
shape unique to a particular pathogen
when you get a vaccine
your immune system sees the antigen and
sounds the alarm that triggers the
formation of memory cells that remember
the bad guys
as well as antibodies that disable the
pathogen if it tries to invade in the
future
now mrna vaccines still accomplish that
goal
but instead of pieces of pathogens or
any other strategy we've used in the
past
they contain messenger rna or mrna for
short it works sort of like giving our
cells
a build your own antigen kit instead of
the actual antigen
the end product is the same but we've
asked ourselves to do the heavy lifting
that's because
cells are kind of better at this stuff
than we are
we can mess around with pathogens all
day but cells
already know how to make antigens if we
just
apply the instructions it's not the only
way to design a vaccine
fast but it's a great tool to have handy
when a pandemic comes along
so how do you program a cell to make an
antigen well
the simple version is you just borrow
the machinery it's already using
see most every cell contains a complete
copy of our genome
the sum total of instructions it takes
to make us
written in dna that information gets
translated into proteins
which do all the actual work of being
alive every protein has a job
specified in the dna instruction manual
when it's time to make a protein
the cell needs to reference those
instructions but dna remains in one spot
the nucleus of the cell proteins
meanwhile are made outside the nucleus
the solution
is to copy out the instructions and send
a message outside the nucleus you might
see where this is going
that message is made of messenger rna
which contains a copy of the dna
instructions
for use in protein making the message
exits the nucleus and makes its way to a
ribosome in the cell this piece of
machinery
reads the mrna and translates the
message into a protein
this is where the clever part comes in
because we know the genetic code
so we can write our own message for the
cell to translate that's what an mrna
vaccine
is a coded genetic message from us to
our cells
for them to work out with their
molecular decoder rings instead of an
antigen
they contain the mrna template to build
an antigen in the case of our covid19
vaccines
the message codes for an antigen called
the spike protein
these spikes stick out of the virus
which uses them
like a key to unlock and infect people's
cells when the shots go into people's
upper arms
the mrna molecules inside make their way
into cells and to ribosomes which are
more than happy to do their job
and translate the message our cells
display the finished spikes on their
surface
our immune system spots them and starts
taking action
from there it's thought that things were
pretty much the same as more traditional
vaccines the immune system makes memory
cells and antibodies
and once those defenses have kicked all
the way in boom
you're ready to fight off the real deal
but while we hope those memory cells
will last a while
the message doesn't it never finds its
way into the nucleus so it can't mess
with our dna master blueprint which
means
it's not manipulating our genes or
anything the effects really are a lot
like every other vaccine you've ever
gotten
these mrna vaccines were designed pretty
quickly in response to the pandemic
but that doesn't mean they came out of
the blue in fact
scientists have known about the
potential of mrna vaccines for decades
but it's taken years of testing and
tweaking to get the technology right
for example researchers had to figure
out how to make the rna molecules last
long enough in our bodies to
actually get translated and they had to
work out the perfect delivery vehicle
to get the mrna into cells and minimize
side effects
even with all that in hand before now no
rna-based vaccine
had ever made it out of the clinical
trials and there was no guarantee they'd
ever work but the ones we have for
covid19 do work at least to the best of
our knowledge
so far they're safe and effective enough
to help get the pandemic under control
and with the technology showing such
promise there's renewed interest in some
older mrna vaccine efforts for things
like rabies and zika some could even
fight cancer so that's what an mrna
vaccine is
a novel form of vaccine that teaches
your cells how to make something your
immune system can learn from
they're not as different as you might
think but they have a ton of potential
mrna vaccines are an elegant way to
address a global crisis
and if you're ready to step up your
appreciation of all the elegant science
and math have to offer
you might enjoy a course from brilliant
like their course on complex numbers
which will help you master algebra by
teaching you euler's formula
considered one of the most beautiful
equations in all of math
brilliant has tons of courses in math
science engineering and computer science
all designed by top tier educators to
get your curiosity
pumping if you're interested you can
check out brilliant.org
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you