Immunotherapy is an emerging field of disease treatment. This treatment involves using the body's immune response to combat diseases such as cancer. Adoptive immunotherapy is one type of this treatment, and it refers to the implantation of immune cells into an infected or cancer-bearing organism.
The cells used in adoptive immunotherapy include tumor-infiltrating lymphocytes (TILs), which destroy tumor cells with powerful enzymes, and lymphokine-activated killer (LAK) cells. LAK cells require the presence of the compound interleukin-2 (IL-2) to begin attacking tumors. For this reason, IL-2 is administered with the cells during treatment.
In this form of immunotherapy, immune cells are removed from the patient, often from the tumor site. TIL cells from these sites present a stronger response to tumors than those found elsewhere in the body. Also, the patient receives IL-2 intravenously during this time.
The immune cells are cultivated outside of the patient in a medium containing IL-2. Then, the cells are re-introduced to the patient. After this infusion, the body will begin to produce more LAK cells, as the re-introduced cells typically mount a strong immune response to the tumors.
Studies have shown that the introduction of cytokines like IL-2 is essential for the success of adoptive immunotherapy. Combining IL-2 and LAK cells in this therapy is typically more effective than using LAK cells alone. The reason for this may be that some tumors are immunosuppressive, and can discourage a nearby immune response. Infusing IL-2 in the patient can help encourage immune cells such as LAK cells to begin attacking the tumor cells.
Adoptive immunotherapy may also involve combining infusions of immune cells like lymphocytes alongside antibodies that specifically target tumors. Antibodies that target a protein present on the surface of breast cancer cells have been employed for this method. When combined with T-lymphocyte immune cells in certain studies, these antibodies helped to create a response that eliminated cancer cells that had spread to other parts of the body.
A variety of cancer conditions can potentially be treated with adoptive immunotherapy. Cancers treated in this way include melanoma, and ovarian carcinoma. Ovarian carcinomas normally induce a strong immune response, so they are particularly excellent candidates for this type of immunotherapy. The immune response to these carcinomas can often predict a patient's prognosis after surgery and chemotherapy.
Other diseases and types of cancer could potentially be treated using adoptive immunotherapy. They include breast cancer, and non-cancer diseases such as Alzheimer's disease. Experiments are being performed to determine how effective immunotherapy is in combating these ailments.