How does our immune system work?

We are continually bombarded with appeals to improve our resistance or strengthen our immune system. But what is an immune system, really? And how does it work?

The immune system is the body’s mechanism for preventing every pathogen, bacterium, or virus that enters the body from causing illness. Every day, we are confronted with millions of these tiny offenders ,which try every way possible to enter our bodies, either via food, breathing, or contact with other people or objects.

The main task of the immune system is to protect the body from these pathogens. The body has developed various mechanisms, known as immune responses, for doing so. These mechanisms occur parallel to one another and protect the body using white blood cells (lymphocytes). The majority of these cells are found in the lymphatic system, which includes the bone marrow, the spleen, as well as the lymph nodes and lymphatic ducts. If needed, some of these cells enter the bloodstream.

Innate immune response: Defending against foreign bodies with hide and hair

Eliminate foreign bodies and pathogens upon initial contact - this sounds like a military order, but it is actually the primary goal of the innate immune response. This is genetically programmed and takes place, using a predetermined repertoire, each time the body makes contact with a pathogen.

In doing so, healthy skin as well as gastric juices play an important role. While the skin and mucous membranes form the initial barriers that the intruder must breach, the gastric juices and their high acid content destroy bacteria and pathogens that have already entered the body through the mouth and nose.

Both tear fluid and saliva already combat these intruders beforehand. For example, the enzyme lysozyme, which is contained in both fluids, destroys the intruders’ cell walls and thus disarms them.

If the unwelcome guests still manage to breach these barriers and reach areas where they can cause damage, defensive cells are released to surround and capture the identified threat, and absorb it within the cell. Intracellular enzymatic processes then destroy the enemy structure rendering it ineffective.

Acquired immune response: Individual solutions for individual problems

While the intruders breach the first barriers, the acquired immune response mechanisms jump into action. Since this response only develops over the course of a person’s life, it is also known as “acquired immune response.”

Its function is based on the principle of adaptation: various cells develop individual defense mechanisms during the initial contact with a pathogen, which are geared specifically toward this pathogen and target its elimination. In order to be armed against another attack by this same type of pathogen, the acquired information is stored in memory cells (similar to a database) and is retrieved when needed.

A very simple way to support your immune response

There is an easy way to support your immune system in order to ensure that it continues functioning smoothly. Consuming five portions of fruit and vegetables per day will provide your body with many important vitamins, minerals, and nutrients needed to maintain a healthy immune function. Adequate sleep and regular physical activity (outdoors) will also help to keep your body in balance.