The following section is on a treatment of cancer, it is not a guide on how to perform it, nor is it a guide as to the side effects or how to prepare for treatment. The following section is designed to give readers an in-depth understanding of the treatment, how it functions, and why it functions. Please note that researchers are constantly working to find new treatments or improve current ones, this means the subject(s) discussed below are likely to change as medicine improves.
The basic principle of immune therapy or immunotherapy is to use the body’s natural immune system to fight cancer. It is recommended to read the section on the immune system before reading this section. As covered in the immune system section the body fights foreign pathogens by identifying antigens, cancer cells often evade the immune system either by having no new proteins, or by having surface proteins that inactivate the immune system. Immune therapy only works if there is an abnormal protein in cancerous cells that can be targeted. There are a few different ways of doing this such as:
Monoclonal antibodies: antibodies that are made outside of the body usually synthetically, although some older techniques used other animals to produce antibodies. These antibodies are specifically made to bind to a target protein that has been identified in the cancerous cells. Antibodies that bind to these proteins and in turn the cancerous cells can inhibit cellular function and/or mark the cell for destruction by the body’s natural immune system.
T-cell transfer therapy: the patient’s T cells will be removed and taken to a lab where they can be enhanced to attack tumors more effectively. This can be done through 2 ways; the first is TIL therapy (tumor infiltrating lymphocytes) where they are tested to see which of the T cells are best at identifying the cancerous cells, the best performing cells can then be induced to replicate, the new T cells can then be reintroduced to the patient. TIL therapy could be compared to selective breeding, for example finding a horse that won a lot of races and breeding it to create many more race winning horses.
The second involves genetic editing, where the T cells are introduced to the CAR gene (chimeric antigen receptor) causing the T-cells to naturally create specific proteins that will bind to the tumor. This is known as CAR-T therapy. (1)
Immune checkpoint inhibitors: There are a large variety of receptors found on most healthy cells in the body that signal to the immune system that they are healthy and should not be destroyed. This is designed to prevent autoimmune diseases. By introducing drugs that block those receptors (usually by binding to them) it can make the immune system far more aggressive often leading to an increase of cancer recognition from the immune system. This can have the side effect of autoimmune diseases.
Treatment vaccines: If the immune system is recognising the cancer cells but slowly or inefficiently, patients can receive treatment vaccines. This is where larger amounts of the antigen immune cells are reacting to is released into the body causing cells that do react to the antigen to replicate more, leading to a bigger immune response. (2)
Immune system modulators: this is where the natural cytokines that regulate the immune system are artificially introduced in order to activate the immune system and cause a larger response. (3)
| 1. | National Cancer Institute. T-Cell Transfer Therapy – Immunotherapy. Cancer.gov; 2022. Accessed July 20, 2026. https://www.cancer.gov/about-cancer/treatment/types/immunotherapy/t-cell-transfer-therapy |
| 2. | National Cancer Institute. Cancer Treatment Vaccines – Immunotherapy. Cancer.gov; 2019. Accessed July 20, 2026. https://www.cancer.gov/about-cancer/treatment/types/immunotherapy/cancer-treatment-vaccines |
| 3. | National Cancer Institute. Immune System Modulators for Cancer Therapy – National Cancer Institute. National Cancer Institute; 2019. Accessed July 20, 2026. https://www.cancer.gov/about-cancer/treatment/types/immunotherapy/immune-system-modulators |
| 4. | National Cancer Institute. Immunotherapy to Treat Cancer. Cancer.gov; 2019. Accessed July 20, 2026. https://www.cancer.gov/about-cancer/treatment/types/immunotherapy |