Immunotherapy: Understanding Its Advantages, Potential Drawbacks, Applications, and Mechanism of Action
Immunotherapy, a treatment that stimulates or suppresses the immune system to help the body fight disease or infection, has become a crucial part of modern medicine. This versatile approach is used to tackle a wide range of health conditions, from allergies to cancer.
One of the most common uses of immunotherapy is in allergy treatment. Allergen shots, for instance, contain a small amount of an allergen to help the body produce antibodies to the substance and reduce allergy symptoms. Immunotherapy is also used to prevent allergic reactions caused by substances such as bee venom, dust mites, and grass pollens.
In the realm of infectious diseases, immunization plays a vital role. Vaccines, developed for conditions such as chickenpox, COVID-19, and yellow fever, teach the immune system to recognize certain infections, thereby preventing them.
Immunotherapy is equally significant in the treatment of autoimmune diseases. By blocking immune activity, the immune system is prevented from attacking healthy tissue. Immunotherapy is used to treat a variety of autoimmune diseases, including rheumatoid arthritis, systemic lupus erythematosus, and psoriasis.
In the field of oncology, immunotherapy has emerged as the fourth pillar of cancer treatment, alongside surgery, chemotherapy, radiation therapy, and targeted therapy. Immunotherapy can enhance the immune system's ability to find and destroy cancer cells, as cancer cells have more than 11,000 gene mutations that differentiate them from healthy cells.
Immunotherapy is used to treat some types of primary immunodeficiency, such as CTLA4 deficiency, LRBA deficiency, leukocyte adhesion deficiency, severe combined immunodeficiency, and X-linked lymphoproliferative disease. Intravenous (IV) immunoglobulin therapy, which involves injecting antibodies from donors, is also used to treat some inflammatory and autoimmune conditions.
During tissue and organ transplants, immunotherapy is used to dampen the immune system to lower the chances of organ rejection. Four types of drugs are typically given during the maintenance phase: calcineurin inhibitors, antiproliferative agents, mTOR inhibitors, and steroids.
Research on immunotherapy for treating infectious diseases such as malaria, HIV, tuberculosis, Zika virus, and coronavirus disease 19 (COVID-19) is ongoing. Helminth therapy, an experimental treatment that involves administering helminth parasites to treat some autoimmune and inflammatory conditions, is also being explored.
The first modern scientific advancement in immunotherapy is often attributed to German doctors Busch and Fehleisen in the late 1800s. In recent years, James Allison's development of a type of immunotherapy called checkpoint inhibitors earned him the Nobel Prize in 2018.
Immunosuppressive drugs are used to suppress immune system activity to manage some autoimmune conditions and prevent organ rejection in people who receive transplants. Types of immunotherapy used to treat cancer include checkpoint blockade therapy, adoptive cell immunotherapy, oncolytic immunotherapy, cancer vaccines, and cytokines.
Immunotherapy is currently being applied in Germany, particularly for cancer treatment. Techniques such as CAR-T cell therapy, radioimmunotherapy, and mRNA vaccines combined with immune checkpoint inhibitors are used in specialized centres like university hospitals (e.g., Erlangen and Hannover). These therapies are used for patients where conventional treatments have failed or as part of clinical studies to expand their applications.
Transfer factors, proteins produced inside the immune system, are currently under investigation for treating conditions such as herpes, yeast infections, and AIDS. As research continues, the potential applications of immunotherapy are expected to expand, offering hope for the treatment of an ever-growing number of diseases.
