Antibodies are fascinating helpers of our immune system – and indispensable tools in laboratory medicine.

What are antibodies?

Antibodies, also known as immunoglobulins, are special proteins that our body produces to defend itself against intruders such as viruses, bacteria or other harmful substances. They are produced by certain white blood cells, the B lymphocytes. Each antibody is like a tailor-made key: it fits exactly to a specific “lock”, the so-called antigen. Antigens are usually molecules on the surface of pathogens or foreign substances that the immune system recognizes as a danger.

The structure of an antibody resembles a Y: at the upper ends of the Y are the binding sites that recognize and hold the antigen. As soon as an antibody has found its target, it marks it – like a kind of alarm bell – and helps other parts of the immune system to fight the intruder or render it harmless.

How do antibodies develop in the body?

When a pathogen enters our body, the immune system becomes active. The B lymphocytes recognize the foreign antigen and begin to produce suitable antibodies. This process can take a few days, which is why we often only feel a strong immune response to a new infection after some time. Once produced, many of these antibodies remain in the blood or in the cells as a “memory”. This is the reason why we are permanently immune to some diseases such as measles after an infection or vaccination – the antibodies are ready in case the pathogen returns.

Antibodies in laboratory medicine

In laboratory medicine, antibodies are used to detect diseases, monitor the course of infections or check the effectiveness of vaccinations. This works because antibodies are so specific: They only bind to “their” antigens and can therefore be used in a targeted manner.

A well-known example is the antibody test. Such tests show whether someone has antibodies against a certain pathogen, such as the coronavirus, in their blood. This can reveal whether a person has already had the disease or whether a vaccination was successful. To do this, you take a blood sample, mix it with known antigens and see whether antibodies bind to it. This reaction is often made visible, for example through color changes or special measuring devices.

Antibodies are also important in the diagnosis of autoimmune diseases. In such diseases, the immune system mistakenly attacks the body’s own structures. These misdirected antibodies can be searched for in the laboratory in order to make a diagnosis – for example in the case of rheumatism or lupus.

Why are antibodies so valuable?

The great advantage of antibodies in laboratory medicine is their precision. They help to detect tiny traces of pathogens or other substances in the body that would be difficult to find using other methods. At the same time, they are a window into the past: they show which dangers our immune system has already come into contact with. This makes them indispensable not only for diagnosis, but also for research and the development of new therapies.

Conclusion

Antibodies are nature’s little marvels. In the body they protect us from diseases, and in the laboratory they provide us with answers to important medical questions. Thanks to their ability to specifically recognize certain substances, they have become an indispensable part of modern medicine. Whether it is a question of detecting an infection or finding the cause of a disease – antibodies are the detectives that help us to better understand and maintain health.

Editorial office: X-Press Journalistenbüro GbR

Gender note. The personal designations used in this text always refer equally to female, male and diverse persons. Double/triple references and gendered designations are avoided for the sake of better readability ected.