Researchers have investigated why older people become more seriously ill from flu and Covid-19. They discovered that an exchange of immune cells contributes to this. For this purpose, so-called macrophages were studied in mice, immune cells that are also called scavenger cells of the immune system.
The scientists were able to show that macrophages, which are present in the lungs and have already developed during the embryonic period, increasingly die in the event of an infection. The more serious an infection, the more such macrophages die, according to the researchers of immunologist Manfred Kopf of ETH Zurich.
Bone marrow cells harmful
After a few days, these embryonic lung macrophages are replaced by those from the bone marrow. However, the latter are harmful in viral lung infections. They provoked a strong inflammatory response. To some extent, the “wrong” scavenger cells go up.
It was previously believed that both types of scavenger cells, those from the embryonic period and those from the bone marrow, have the same functions. The study’s two first authors, Federica Piattini and Fengqi Li of Kopf’s research group, have now refuted this.
Loss of macrophages in old age
According to Kopf’s research group, the exchange of macrophages also takes place in aging mice without having undergone an infection. According to Kopf, there are several reasons why flu and coronavirus infections in the elderly are much more serious. However, the new data would indicate that the loss of embryonic macrophages over the course of life contributes to this.
The researchers conducted their experiment on mice with flu viruses and compared the results with coronavirus infections in humans – according to the scientists, this is obvious and allowed. The researchers published their results in the journal Science Immunology.
Source: Krone
I’m Wayne Wickman, a professional journalist and author for Today Times Live. My specialty is covering global news and current events, offering readers a unique perspective on the world’s most pressing issues. I’m passionate about storytelling and helping people stay informed on the goings-on of our planet.
