Antigens and Antibodies – What’s the Difference?

You may have wondered what the difference between an antigen and an antibody really is. What is what and how they are connected. And where does the virus come into the picture?

In short, it can be explained that when an antigen enters the body, for example from a virus, it contributes to the production of antibodies. Both work together in an antagonistic process with each other. When the body produces antigens, antibodies are produced for the specific antigen. So what exactly is an antigen and an antibody?

Wikipedia describes antigens and antibodies as follows; Antigen (Ag) is a combination of the words antibody generator and is what in immunology is called a foreign body substance that provokes a reaction in the immune system when it enters the organism. This foreign body substance can be a chemical substance, a protein or a carbohydrate. This reaction leads to the formation of new antibodies and the recruitment of white blood cells that attack the antigen. In autoimmune diseases, the body automatically forms antibodies against healthy or functioning tissues or body structures ”. Source: Wikipedia

What happens when an antigen enters the body?

The antigens can be found in the cell surface of many bacteria, fungi, viruses, dust particles and other cellular and non-cellular particles. When an antigen enters the body, the body’s immune system reacts with a series of activities. These activities are what we call the body’s immune system. These activities usually consist of the formation of protein or polysaccharides and the formation of antibodies. The antibodies that the body produces are there to defend the body against the antigen attack and to destroy the antigens.

Examining whether you have antigens or antibodies is a way to determine if you are currently carrying a specific infection or if you have previously been exposed to the infection and thus formed antibodies.

What is the difference between antibody and antigen?

  • Both antigens and antibodies are important for our immune system. And both are involved in autoimmune diseases.

  • Antigens and antibodies are both microscopic particles that contain proteins.

  • Antigens also have combinations from polysaccharides

  • Antigens can be cells

  • Antibodies are never cells

  • Antigens act as the key to getting into the body

  • The antibodies act as the body’s lock and guard

  • Antibodies can be described as Y-shaped and they are the two “arms” on the Y that act as locks.

  • There are essentially two different types of antigens. Independent and non-independent. Independent antigens usually do not cause a reaction from the immune system except in special cases and that is when we talk about autoimmune diseases. Dependent antigens, on the other hand, cause a reaction.

Antigen and Antibody tests

We looked at the difference between antigens and antibodies and what they really are. What, then, is the antigen and antibody tests actually measuring?

  • SARS-CoV-2 Ag test, also called Coronatest or antigen test, is a good test to quickly and easily examine whether you are wearing COVID-19. It is therefore a test to see if there are antigens in the body.

  • SARS-CoV-2 IgG / IgM test or Antibody test shows if you have been infected with COVID -19 and if antibodies have been formed in this way.

It is important to remember that if you test positive for antibodies and it shows if you have undergone an infection, it is currently unknown how long that immunity lasts with COVID-19. This means that even if you test positive for antibodies, you should still follow all precautionary measures recommended by the Swedish Public Health Agency. You can read more about our antigen and antibody tests here.