Macrophages are white blood cells with a number of important functions. Without this macrophage processing, the T and B cells could not respond to some types of antigens. NK cells are cytotoxic to tumor cells and virus-infected cells. Many cells in the immune system produce chemicals that aid in regulating the immune response. These substances are referred to as mediators and broadly referred to as cytokines .
Many cytokines are under study, to determine their effect on the immune system.
A brief review of BRM agents currently being evaluated follows. Samples of the patient's tumor cells are taken and processed to reveal specific antibodies to the tumor-associated antigens. In order for this approach to work, a sufficient quantity of antigens unique to the tumor cells must be present. In addition, the tumor antigens must be sufficiently different from the antigens elaborated to by normal cells to provoke an antibody response. The antibodies can be used either alone to kill cancer cells or as carriers of other substances used for either therapeutic or diagnostic purposes.