mRNA and Working Mechanism of mRNA-Based Covid19 Vaccines
When a virus enters our body, it attaches to the surface of our cells. Depending on the type of this virus, its DNA or RNA enters the cells from the part it is attached to. Our cells begin to produce copies of the virus using this DNA or RNA as if they were a factory and spread it throughout our body, without questioning, due to their duties. After a while, our immune system notices this production that takes place in our body. It understands that the substances produced are foreign, plans how to fight against them, and takes action. This process often takes several days. In other words, the ailments that we show symptoms of have entered our body long ago, without our being aware of it, and have begun to spread. What causes this spread is our own cells, which are unaware of what is happening, only performing the production task.
After our immune system decides how to fight these viruses, it begins to synthesize substances called “antibodies”. These are the weapons of our immune system. These antibody proteins attach to the viruses in our body and prevent them from infecting more cells and mark them for destruction. While these events are taking place, we begin to show symptoms such as fever etc. The immune system is a system that works more slowly than other systems. So this war and the disease that comes with it can take weeks.
Here in order to speed up this slow-running system, to enable it to decide more quickly how to react in which situation we need to be vaccinated first. In short, the vaccine is a way of telling the body, “if you come across this substance, you have to kill it”.
The most effective type of vaccine is mRNA vaccines, which can be produced in less time compared to other vaccine production methods and give the most effective results. Because it is enough to know the DNA or RNA of the virus to produce it. This method, which was previously used in vaccines against diseases such as flu, rabies, polio, was also used in Covid19 vaccines.
The molecule we call mRNA is a messenger molecule that tells the cell what to produce and how, and gives instructions to the cell, just like the recipes we use when cooking in the kitchen. While our body synthesizes a protein in its usual course, it first synthesizes mRNA from our DNA. The mRNA carrying the description of the protein to be produced comes to the organelle called “Ribosome”, where protein synthesis takes place, and the necessary protein is synthesized there. Since the mRNA molecule has now completed its task, it is destroyed by the cell.
The mRNA in the mRNA vaccines produced for Covid19 carries the description of the “spike” protein that allows the Covid19 virus to attach to the cell. When we are vaccinated, the mRNA carrying this instruction enters the cell, allowing our cells to produce this attach protein. However, since these spike proteins are foreign substances to our body, our immune system also attacks them. In this way, it meets them. When the attack is over and our bodies are victorious, immune system stores the new information it learns in memory cells called “B lymphocytes” that this spike protein is foreign to the body, that it must attack when it sees it. A booster dose called a “booster shot” may need to be shot after a while to maintain vaccine-induced protection against a disease, as immunity may decrease over time. Some vaccines, such as measles, mumps, and rubella, usually provide lifelong immunity, while vaccines such as the flu vaccine may need to be repeated periodically.
Since vaccines produced by the mRNA method cause a part of the virus to be present in our body, not the whole, its side effects are less than traditional vaccines. It is often said that “flu-like side effects” occur. In traditional vaccine production methods using weakened virus or inactivated virus, more severe side effects can be seen as the entire virus enters our body.
