What is immunosuppression?
Immunology deals with the biological and biochemical bases of the physical defense system. Pathogens such as bacteria and viruses as well as other foreign substances and environmental toxins, for example, initiate immune responses. With different disorders and malfunctions of the defense mechanisms, the detection and inactivation of foreign substances by the immune system no longer runs smoothly.
The human immune system plays a central role in many diseases. All disorders of the immune system are therefore the subject of immunology. The same applies to therapeutic approaches with an immunological basis. One such approach is immunosuppression. It is the therapeutic suppression of all immune processes. Immunosuppressants are used to inactivate immunologically undesirable and misdirected processes and have proven to be a solid component of therapy in various indications. Among the best known immunosuppressants is interferon. The effects of immunosuppressive drugs are differentiated into extracellular and intracellular effects.
Function, effect & goals
In immunosuppression, external intervention unphysiologically inhibits or suppresses the immune response. Therapeutic immunosuppression can occur at different levels. All levels have interventions in the synthesis or signaling pathways of the immune system in common. One possibility for such intervention is the inhibition or destruction of immune stem cells in the bone marrow.
Apart from that, protein biosynthesis in immunocompetent cells can be inhibited by immunosuppression. Immunocompetent cells produce antibodies. Their inhibition thus results in a reduced antibody production, which has an immunological weakening effect. In addition, in the context of immunosuppression, the interleukin-mediated signaling pathways in the immunological lymphocytes can be interrupted or blocked. Thus, the regulation of the immune system is influenced from the outside and can be adapted to the individual case accordingly. Different states represent an indication for immunosuppressive treatment. In general, immunosuppressants are always used when immunological processes cause harm to an organism. This is the case, for example, with transplants.
If the immune system detects the transplanted organ or tissue as foreign, it attacks the foreign substance and initiates a rejection reaction. Since the standard introduction of immunosuppression before transplantation, the risks of rejection have decreased significantly. An equally relevant role plays immunosuppression for patients with autoimmune diseases. Autoimmune diseases are diseases with excessive reactions of the immune system, which are directed against the body's own tissue instead of against pathogens.
The immune system of the patient recognizes the tissue of his own body as a foreign body to fight and causes severe inflammatory reactions in the affected structures. Organ damage can be the result, in multiple sclerosis for example, irreversible damage and thus loss of function of the brain. Even patients with allergies often receive permanent immunosuppressants. Allergies are hypersensitivity of the immune system, which can be suppressed or at least mitigated by immunosuppressive therapies.
As a rule, immunosuppression occurs in allergy and autoimmune patients in the form of a drug-prophylactic long-term treatment. While transplants, allergies and autoimmune diseases are a medical indication for therapeutic immunosuppression, the body may also be involuntarily affected by immunosuppression. Pathological immunosuppression is known to exist in diseases such as HIV. An immune deficiency is the result. Weakening of the immune system can also be observed in the immunosuppressive effect of UV-B rays.
Excessive UVB exposure to the skin therefore promotes the development of malignant skin tumors and reduces the defense against pathogens such as fungi and bacteria. In addition, physical and mental overload lead to a suppression of different immune parameters. This immunosuppressive effect is known to cause infection susceptibility in congestion situations.
Risks, side effects & dangers
Therapeutic immunosuppression is associated with significant risks and side effects. This is especially true for oral immunosuppressants that do not work locally, but have their effect throughout the body. The targeted suppression of individual parameters is so far impossible. Therefore, immunosuppression dampens the immune system overall.
Both in front of infection and cancer cells, the body is consequently less protected. A common side effect of immunosuppression is mucositis, an inflammation of the mucous membranes. Often this reaction occurs in chemotherapy or radiotherapy and is referred to in this case as radiogenic mucositis. The inflammatory reaction can spread throughout the digestive tract. In immunosuppressed patients and patients with autoimmune diseases mucosal inflammation usually corresponds to infection with different pathogens. The weakened immune system of the patients is particularly susceptible to pathogens such as fungi, viruses or bacteria. These pathogens cause inflammation of the mucous membranes, which the physician also knows of patients with poor general and nutritional status, elderly patients or HIV patients.
Some immunosuppressants are also associated with side effects such as blood pressure disorders, blood sugar abnormalities, and cholesterol elevation. In addition to the kidneys and nerves, many of the drugs put pressure on the liver, cause nausea or even vomiting or damage the gastrointestinal tract. Depending on the drug, fatigue, depression and confusion can also occur. Specifically, the risks and side effects of immunosuppressive therapy are highly dependent on the particular drug and dose administered. Due to the numerous risks and side effects, the advantages and disadvantages of immunosuppressive therapy must be weighed individually for each patient. Only if the benefit clearly outweighs the treatment is indicated.