Autoimmunity and Immune Dysregulation in Long COVID

Infection with the SARS-CoV-2 virus leads to acute COVID-19 illness. For some, this acute infection leads to severe illness and hospitalization. For others, symptoms are mild, or they may even be asymptomatic. Whether the original infection was severe or even asymptomatic, however, the virus can greatly interfere with the body’s immune system, damaging healthy cells, leading to symptoms similar to those seen in many autoimmune diseases, such as rheumatoid arthritis and lupus. But what is causing this immune dysregulation and what does it mean for those that have had COVID-19?

A Healthy Immune System

The immune system is your body’s natural security system that works to keep you healthy and fight off potential invaders, such as bacteria and viruses. The immune system is subdivided into two categories by role or job: innate immunity and adaptive immunity.

Innate immunity is the immune protection you are born with. It includes the physical barriers, such as the skin and the lining of your intestinal tract, that help to keep potential pathogens from entering the body. It provides general protection without the ability to recognize specific strains of bacteria or viruses. When something breaks its barrier, you can experience fever or inflammation as an initial form of defense. In addition to these physical barriers, there are white blood cells, such as basophils, dendritic cells, eosinophils, Langerhans cells, mast cells, neutrophils, and NK cells that help mediate innate immunity.

Adaptive immunity describes the parts of the immune system that ‘learn’ from the pathogens that breakthrough and trigger an immune response. These pathogens that trigger the immune response are called antigens. When these antigens enter the body, certain white blood cells (leukocytes) find them and initialize the attack. When this happens, the B lymphocytes, or B-cells, create antibodies to the antigens while the T-cells focus on eliminating them. The creation of antibodies from the B-cells highlights the adaptive nature of the immune system. Once created, these antibodies recognize the antigen the next time they encounter it and immediately begin to attack the pathogen.

What is Autoimmunity and Immune Dysregulation?

Unfortunately, the immune system is not without complications. Sometimes this powerful security system can have faulty wiring and attack healthy cells within the body. Autoimmunity and immune dysregulation may occur when the B-cells produce autoantibodies directed against healthy, normal cells within the body. When the body creates these autoantibodies, the T-cells recognize these healthy cells as invaders and begin the attack. This results in the many symptoms seen with autoimmune conditions, such as rheumatoid arthritis and lupus.

But what causes the immune system to malfunction and attack itself? Currently, the exact cause of autoimmunity and immune dysregulation is unknown. However, the main theory is that bacteria, viruses, certain medications, and even environmental or chemical exposure can cause confusion within the immune system. Autoimmunity is also more prevalent in people with certain genetic predispositions.

How is Long COVID Triggering Changes in the Immune System?

As previously mentioned, one theory behind autoimmunity is a viral infection causing confusion within the immune system. When it comes to the SARS-CoV-2 virus, researchers are finding that people with COVID-19 are producing many different autoantibodies. These autoantibodies are still present six months after they have fully recovered from the initial infection. Moreover, these autoantibodies aren’t just in patients who experienced severe symptoms, but also in asymptomatic individuals. This change in the immune system may be behind many of the symptoms experienced by people with Long COVID, as well as those receiving Guillain-Barre or other immune disease diagnoses following SARS-CoV-2 infection.

What Can We Do to Treat Autoimmunity?

While there is no cure for autoimmune diseases, there are a variety of treatment options available. These treatments focus on reducing symptoms and slowing disease progression. Medications, such as anti-inflammatory drugs and immunosuppressant drugs, are commonly prescribed for autoimmune conditions. Researchers are currently exploring whether similar treatment options will benefit those with Long COVID.

Get updates

Join our mailing list