Our immune system evolves to fight coronavirus variants

This article by Monuique Brouillete was published by the Scientific American on March 31, 2021. It features a new study conducted by Michel Nussenzweig, an immunologist at the Rockefeller University, which showed that the human immune system can evolve to more effectively handle variants.

The article clarifies the different kinds of immune cells that have the capacity to create different kinds of antibodies. According to research, neutralizing antibodies produced by the normal B cells, are the specific agents that deactivate the virus. However, neutralizing antibodies tend to wane some time after the encounter with the original virus. This is only natural, according to immunologists, as this means that the infection has been “defeated” by the normal B cells. In the process of fighting the original virus, the immune system also produces memory B cells. The memory B cells sustain the capacity to recognize the original virus, which in turn, allows the body to create the appropriate antibodies should there be a renewed attack from the same virus. Nussenzweig says that the memory B cells themselves, which are stored in the lymph nodes, undergo mutations. This enables the mutated memory B cells to recognize new mutations in the virus, and thus produce the appropriate antibodies to defeat new variants of the virus.

According to the article, a third kind of immune cells, the killer T cells (CD8+), prevents serious COVID illness. Unlike the neutralizing antibodies and antibodies created by memory B cells, these cells do not go after pathogens directly, but seeks out cells infect by virus that may have penetrated the defense of the B cells. A study conducted by Shane Crotty and Alessandro from the La Jolla Institute for Immunology found that T-cell immunologic response of people who were exposed to SARS-CoV-2 through natural infection or vaccination were not dampened by new virus variants.

Editor’s Note: This article drives home the reality that our immune system has the capacity to overcome even the new variants of SARS-CoV-2. Essentially this means that the best real defense against COVID-19 is still a healthy immune system. And as there is no one organ for the human immune system, it essentially highlights the importance of keeping the entire human body healthy in order to prevent serious complications due to COVID-19. It helps us understand why it is the elderly and those with co-morbidities who experience the greatest threat from COVID-19, because their immune systems are not as robust as younger, and healthier individuals. The article drives home the fact that if governments want zero COVID-19 diseases, then they had better focus on preventing chronic diseases that make COVID-19 infection likely and deadly. Even the vaccines can work only because the human body they are injected to has the capacity to develop antibody responses.

This article also helps us understand Dr. Knut Wittkowski, who believes that by locking down, countries have effectively prolonged the epidemic [see Dr. Knut Wittkowski: Lockdowns are creating a new epidemic]. Lockdowns do not develop healthy and resilient adaptive immune systems. It’s like building a muscle, if you don’t use it, then it doesn’t develop. Our immune systems need to be challenged in order for it to become stronger. It also enlightens us to the fact that all our sterilizing (both our hands and our homes) can make us more sickly as we cut our natural connection with nature’s microbiome [to understand this better, see Our complicated relationship with viruses].