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How Will the COVID-19 Vaccine Work - THREAD:
All cells express proteins on their surface. These are called cell surface receptors. This is how the human immune system recognises bacteria or viruses. The cell surface receptors are different to anything it's seen, so it attacks it
All cells express proteins on their surface. These are called cell surface receptors. This is how the human immune system recognises bacteria or viruses. The cell surface receptors are different to anything it's seen, so it attacks it
Old viral vaccines worked by injection or ingestion of a small amount of virus. This virus would be engineered so that it could not infect cells. Another technique was to inject the actual viral cell surface protein itself. Both ways would simulate infection & an immune response.
As mentioned in our 'Immune System' thread, this would activate your innate and finally adaptive immune systems, leading to T cell and B cell activation, producing antibodies. The T cells and B cells would eventually deactivate and turn into memory cells, saving the info for life
There are currently two vaccines in the final phases of trials, Germany's Pfizer vaccine and the Russia's Sputnik V Vaccine. Today we'll only be talking about Pfizer, but they both work in very similar ways. Upon request, in future threads we can go into more detail on Sputnik V
You've probably heard that Pfizer's vaccine uses a 'new technology' called mRNA. This 'm' stands for messenger RNA. RNA is similar to DNA, but it's one stranded. But, this is not new technology. Your cells make mRNA every day. They use it to make proteins.
Your DNA is made up of genes. Your genes make you. The genes code for specific proteins. This genetic profile is what makes everyone unique. But to make proteins, these small sections of DNA (genes) are made into mRNA. Only in this format can the info be turned into proteins.
The Pfizer vaccine is an mRNA vaccine. This specific mRNA encodes for the protein on the cell surface of COVID-19. This is called the 'covid spike protein'. By placing COVID mRNA into your cells, they produce the spike protein, thinking its producing proteins from its own genes!
This technique is really smart and is basically gene therapy. The spike protein is then released into your bloodstream by your own cells and the immune system responds, as it would do to a normal infection.
The mRNA is really unstable, so it has to be delivered to cells in a protected vehicle. This protected vehicle is called a lipid nanoparticle (LNP). Lipids are basically fat but LNPs contain receptors that enable them to fuse w/cells so the mRNA can enter.
This method of vaccination has a lot of pros and cons. Tomorrow, we'll look into these in greater detail. Hope you enjoyed the thread and see you tomorrow!
