How Covid-19 Ages Us

Our immune system has taken on an unexpected important role amid the COVID-19 pandemic. This complex network of cells, tissues and organs is the main weapon our body has to defend itself against the SARS-Cov-2 virus.

Like any other part of our body, the immune system ages over the years. Which leaves us more vulnerable to infections, cancer, and all kinds of diseases. However, the age of the immune system does not always coincide with chronological age. There may be people with 80 years of age but with an immune system of a person of 62. Or vice versa. The great thing is that we ourselves can slow down the aging of the immune system with a few simple steps.

Functioning

The immune system has two branches. Each of them is made up of different types of cells. On the one hand there is the so-called innate response. Which is the first line of defense that is activated almost immediately when the presence of a foreign organism is detected. This response contains neutrophils. They mainly attack bacteria. Monocytes, which help organize the immune system by alerting other immune cells that there is an infection. And the killer cells (NK). Whose job is to fight viruses or cancers. These 3 cells don’t work well when we get older.

There is also the adaptive response. Which is made up of T and B lymphocytes that fight a specific pathogen. It takes a few days for it to activate, but once it does, it will remember the pathogen for the future and fight it again. If it reappears. When we get older, we make fewer lymphocytes. What do you need to fight a new infection like COVID.

Even the ones your body created in the past to fight another infection don’t work very well anymore either. That is, aging causes a tremendous decline in all functions of the immune system. The loss of cells that store the memory of pathogens means that as we age, we not only lose the ability to respond to an infection. But also to the vaccines that prevent them.

In the case of vaccines, 40% of adults over 65 do not generate a response to the vaccine. In addition, age generates more inflammation in the blood and tissues. All these changes that the body undergoes when we get older, make it more difficult for us to recover from an injury or infections that can become chronic. Infections that are under control can appear such as herpes zoster, tuberculosis, flu, pneumonia and the incidence of cancer.

Although we all suffer a deterioration, whose trajectory is foreseeable. What varies is the rate at which each individual does it. Influenced by genetics, but also by lifestyle. Now, thanks to the research of Shen-Orr and his team in collaboration with Stanford University in the USA, it was possible to analyze the composition of 18 types of cells of the immune system. And by the expression of the genes in a blood sample, it was possible to establish at what stage of the aging process the immune system of a person is.

In the next post, we will talk about how the aging of the immune system can be slowed down.