G-CSF and GM-CSF
These cytokines that causes the bone marrow to make immune and blood cells, thereby reducing the risk of infection in patients receiving chemotherapy. These are also being tested against cancer as a non-specific immunotherapy and as an adjuvant given with other types of immunotherapy. Clinical trials of these cytokines, alone or with other immunotherapy, are under way for different various cancers.

Some other drugs such as thalidomide, lenalidomide, imiquimod and levamisole also boost the immune system in a non-specific way, similar to cytokines.

Other ways to boost the immune system
Some other forms of immunotherapy are being studied to boost the specific parts of the immune system. These types of treatments have shown promise, but they could be very complex in operation. Following approaches are being studied.

Lymphokine-activated killer cell therapy
Scientists can make large numbers of active, cancer-fighting T cells in the lab by treating a small number of a patient's T cells in a test tube with the IL-2. After being returned to a patient's bloodstream, these special cells, now called lymphokine-activated killer cells ( LAK cells), are more effective against cancer cells. Researchers are now testing several ways to use these very active cancer-fighting cells.

LAK cell therapy has shown promising results in animal studies, where it shrunk tumors in animals with lung, liver, and other cancers. Although clinical trials in humans have not yet been as successful, researchers are constantly improving LAK cell techniques. They are testing these newly improved methods against melanoma, brain tumors, and other cancers.