What is immunotherapy?

Immunotherapy is a cancer treatment that engages your immune system to fight the disease. The treatment is sometimes called biological therapy.

What is the immune system?

Your immune system is made up of various organs, antibodies (proteins) and immune cells that work together to fight disease and infections. Immune cells include:

  • B-cell lymphocytes: These white blood cells produce infection-fighting antibodies.
  • T-cell lymphocytes: These white blood cells target and destroy diseased cells. T-cells also alert other cells to the presence of diseased or foreign cells.
  • Dendritic cells: These immune cells interact with T-cells to stimulate an immune system response.
  • Granulocytes: These white blood cells — neutrophils, eosinophils and basophils — fight infections.

How does immunotherapy work?

Immune cells produce cytokines, protein molecules that act on other cells. Immunotherapy introduces large amounts of these proteins into the body. The treatment:

  • Stimulates the immune system to produce more disease-fighting immune cells.
  • Makes it easier for the immune system to identify and target cancer cells.

What does immunotherapy treat?

Immunotherapy treats different types of cancers , including but not limited to

The main types of immunotherapy that healthcare providers use to treat cancer include:

  • Adoptive cell therapy: Healthcare providers remove, change and then reintroduce a person’s modified immune cells into the body. The modified cells seek out and destroy cancer cells. CAR T-cell therapy modifies T-cells with chimeric antigen receptors (CAR) that fight cancer. Other therapies include natural killer cells (NKs) and tumor-infiltrating lymphocytes (TILs).
  • Cancer vaccines: Vaccines stimulate an immune response to protect the body against certain diseases. The human papillomavirus (HPV) vaccine protects against an infectious disease that causes cervical, anal, throat and penile cancers. There’s also a vaccine for hepatitis B, which causes liver cancer.
  • Immunomodulators: These substances change the body’s biologic response. They stimulate the immune system’s ability to find and kill cancer cells. Treatments include checkpoint inhibitors, cytokines, interferon and interleukins.
  • Monoclonal antibodies: These lab-made proteins attack specific parts of a cancer cell. Monoclonal antibodies can also deliver drugs, toxins or radioactive material directly to tumors.
  • Oncolytic viruses: Specialists change these viruses in the laboratory. The modified viruses infect and kill cancer cells.

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