The human immune system is a biological defense system that protects against disease. Immunotherapy can help stimulate a weakened immune system or suppress an overactive immune system.
What is immunotherapy?
Immunotherapy is used when the human immune system fails. The immune system is then unable to detect and remove a variety of harmful pathogens (such as viruses) or substances. Immunotherapy is used when the human immune system fails. This can mean that it is no longer able to detect and remove a variety of harmful pathogens or substances, render the body’s own defective cells harmless, or distinguish harmful foreign bodies from the body’s own healthy tissue. The term immunotherapy covers various treatment approaches that aim to influence a failing immune system. Depending on the disease, these therapeutic procedures are aimed at either strengthening (activation) or weakening (suppression) the immune system. Immunotherapy can be divided into the following procedures. The stimulating (activating) procedure strengthens the immune system, while the modulating procedure alters its response. In suppressive immunotherapy, the immune response is suppressed.
Function, effect, and goals
Immunotherapy has become increasingly important in recent decades, especially in cancer treatment, autoimmune disease therapy, and organ transplantation. The term “stimulatory immunotherapy” encompasses a wide range of different procedures and applications. These include active vaccinations with killed or live pathogens that strengthen the normal, healthy immune system and stimulate it to produce antibodies. Immunostimulants can further be administered to activate a weakened immune system in cancer. More and more oncologists are placing hope in immunotherapy. For colorectal cancer, for example, active-specific immunotherapy (ASI), which involves injecting a vaccine made from tumor antigens, is showing efficacy. The immunostimulants interferon and interleukin suppress cell growth, enhance the immune response and are also effective in some tumor types. Furthermore, personalized immunotherapy, including treatment with the body’s own dendritic cells, is used for cancer. The latter procedure aims to destroy a tumor through targeted activation of the immune system. Vaccines against cancer-causing viruses and monoclonal antibodies (immunologically active proteins) are being used with increasing success in cancer immunotherapy. In principle, cancer immunotherapy offers a more targeted, selective effect against cancer cells compared to traditional chemotherapy or radiotherapy. However, immunotherapy alone is usually not sufficient to treat cancer, and additional surgery or chemotherapy must be performed. Modulatory (specific) immunotherapy has long included hyposensitization for the treatment of allergies, and its efficacy is particularly high for seasonal allergies such as hay fever. In this form of therapy, the overreacting immune system is habituated to the allergenic substance by injecting or orally administering an allergen extract, which reduces the symptoms and ideally causes them to disappear. Suppressive immunotherapy is particularly important in organ transplantation. This treatment includes therapies with glucocorticoids, cytostatics and antibodies (immunoglobulins). The aim of this treatment is to ensure that a transplanted organ is not rejected. The patient must take immunosuppressive drugs for the rest of his or her life to suppress the immune system’s defense reaction against the transplanted organ. Other areas of application of suppressive immunotherapy are the numerous autoimmune diseases, including diabetes mellitus type 1, multiple sclerosis, ankylosing spondylitis, Crohn’s disease and rheumatism. These diseases are triggered by an excessive reaction of the immune system, which mistakenly fights the body’s own tissue like a foreign body, causing severe inflammation and organ damage. Here, immunotherapy dampens the activity of the immune system.
Risks, side effects and dangers
Depending on the type of immunotherapy and the patient’s condition, side effects and dangers of treatment vary. Allergy patients who are administered an allergen, i.e., an allergy-triggering substance, in the form of modulating immunotherapy are at risk of a mostly mild allergic reaction, but in the worst case it can lead to allergic shock, sometimes with a fatal outcome. Therefore, hyposensitization must always take place under medical supervision. Suppressive immunotherapy, which is often permanent and lifelong, as in the case of organ transplantation, can also have serious side effects and dangers. Basically, this therapy weakens the patients’ physical defense system and makes them susceptible to a variety of infections. In the long term, the weakened immune system also increases the risk of developing cancer. However, these side effects and dangers of immunotherapy must always be seen in the context of its benefits. Immunotherapies are not miracle cures, but in principle they offer the chance of increased quality of life and prolongation of life.
