mRNA technology is new and has caused much excitement in the scientific world, and in parallel will cause much worry for those who find it scary. The world of social media is alive with such fears, and I wont provide links to them as the ones I have looked at seem wide of the mark when it comes to accuracy.
The vaccine mRNA is absorbed into the cell in its bubble like envelope made from two layers of fat, releases its mRNA into the cell. This then acts as a blueprint which tells the protein making structure of the cell make a bit of the Sars-Cov-2’s spike. The picture below shows this, with the vaccine on the right and the normal viral RNA on the left.
The fundamental point is the unlike viral RNA, the vaccine mRNA is NOT inserted into the DNA of our Genome.
Think of viral RNA as a toolkit needed to complete its task of replication – it needs an array of genes to do this, rather like a toolbox full of spanners, screwdrivers, hammers and so on, while the vaccine mRNA just has one spanner – to do one specific job. It’s also a tool that soon dissolves as its delicate structure cannot last long. (Hence the problems with storage)
For those with an interest in the structure of the cell (why would anyone not be??), the picture below shows the endoplasmic reticulum where much of the protein is made.
JARGON BUSTER….Just to decipher…..endo=inside, plasmic=space, reticulum= network. All medical students soon learn that to call complex intracellular structures names like, “the network in the space inside the cell” won’t look at all clever. Endoplasmic Reticulum would mean just that to the Romans! A complex network inside the cell to make proteins.
Translate it into Latin and Bingo! This can make our own biology somewhat inaccessible but does mean we professionals can look and sound clever. Anyway, this is a schematic look at the wonderful structure with the even more interesting Golgi Apparatus to its bottom rightl. With this structure the trick is to name it after its discoverer.
With all the vaccines, once the proteins are manufactured, they are released into the blood and our own immune system does the rest, recognising the protein as foreign, making T Cells (killer cells) and B cells (antibodies) to remember it for the next time.
The Oxford Vaccine
Before the trials, scientists had worried that the body might develop immunity to the vector as well as to proteins from the coronavirus. The findings hint that anti-vector immunity might be a factor in the regular two-dose regimen. A larger first dose could prime the body to develop antibodies to the vector, thus reducing the efficacy of the second dose. A smaller first dose might get around this problem. The researchers expect to have more information in the weeks ahead that will improve confidence in this result.
Also vaccines in the immunocompromised …..