A booster vaccination helps in the production of antibodies. But the immune system has even more weapons in the fight against a corona infection.
Frankfurt – The most important means of coping with the corona pandemic is the booster vaccination. A “very offensive and fast” booster strategy should keep the number of new infections through the Omikron variant as low as possible, assured Federal Health Minister Karl Lauterbach (SPD) at several press conferences and interviews.
As soon as our body has to fight the coronavirus, what counts is the so-called antibodies. A vaccination is supposed to stimulate the immune system to produce the Y-shaped proteins. But against the strongly mutated Omikron variant, the first and second vaccinations no longer seem to be sufficient. Although antibodies are important in fighting off Covid 19 disease, they are not our body’s only weapon against the virus.
Coronavirus: This is how the immune system reacts
Rather, there is “a complex and coordinated response” from our immune system to the threat, says immunologist Roger Shapiro from Harvard University. Signal proteins put our bodies on alert in the first minutes and hours after contact with the virus. “It’s like bombing the whole area and hopefully the intruder will be harmed as best you can,” said John Wherry, an immunologist at the University of Pennsylvania.
First of all, our body puts so-called neutrophils in front of the viruses. They make up 50 to 70 percent of our white blood cells. The neutrophils fight the pathogens quickly, but they also die quickly. There are also macrophages, which devour the pathogens and excrete crucial components in order to train the body’s natural killer cells to target the pathogen.
Corona: T cells – “killers” and “generals” of our immune system
If the virus is not completely neutralized by the first immune reaction, the adaptive immune defense kicks in a few days after the infection. The B cells, a type of white blood cell, start producing antibodies. A corona vaccination trains the body’s reaction. Especially in the lymph nodes in our armpits near the puncture site. A supply of B cells that are trained for the coronavirus is created there.
The most important allies of the B cells are the T cells, which are divided into T helper cells and T killer cells. Killer T cells are comparable to “murderers,” says Harvard immunologist Shapiro. “They go out and attack the cells that have been infected.” The defense reaction can lead to inflammatory proteins, which are exerted on the body. Depending on the speed of this reaction, a vaccinated person with a breakthrough vaccination may experience mild, cold-like, or flu-like symptoms.
The helper cells are “like generals,” added Shapiro. They develop a battle plan, stimulate the B cells to produce antibodies and instruct the T killer cells which cells to attack.
Omicron variant: Booster boosts antibody production
The omicron variant manages to escape the antibodies due to its numerous mutations. An infection with symptoms is therefore more likely. Unlike antibodies, the T killer cells do not release the pathogen as quickly and are able to locate the essential components of the virus in infected cells in the long term, explains immunologist John Wherry. A booster vaccination increases the production of antibodies and also seems to train the B and T cells.
But with a third vaccination it will most likely not be enough. Lauterbach explained in an interview with WDR 2 that one had to be prepared for a fourth vaccination in the course of the year. When this is the case depends on how long a booster vaccination protects. (aa / afp)
