08/23/2023

How COVID-19 Changes the Immune System

The innate immune system is the body’s first line of defense

If the COVID-19 pandemic has done one thing, it’s made us all more familiar with some of the important players in the immune system. Antibodies, B cells, and T cells are among the best known parts of the body’s response to a virus like SARS-CoV-2, but they don’t act alone.

In a paper published on August 18 in the journal Cell, scientists report that innate immune cells—a critical part of the immune system activated to battle COVID-19—remain altered for at least a year after infection. The finding suggests that these cells may play a role in some of the lingering symptoms associated with Long COVID, although more studies are needed to confirm that connection.

The innate immune system is the body’s first line of defense, made up of general pathogen-fighting cells that are designed to recognize and fight off all kinds of pathogens, including bacteria, viruses, fungi and parasites in a non-specific way. (B cells and T cells, in contrast, are more customized to remember and recognize specific pathogens, and only those pathogens.) Steven Josefowicz, an associate professor of pathology and laboratory medicine at Weill Cornell Medicine, and his colleagues found, however, that even innate immune cells retain some memory of fighting SARS-CoV-2 after a severe infection. This recall, and the response it generates, can last for at least a year after infection.

Please select this link to read the complete article from TIME.