ABSTRACT
The concept of immunosurveillance of cancer, formulated approximately three decades ago, provided a framework for experimentation to test whether the immune system does indeed play a critical role in the protection against cancer. In the past 10 years, numerous antigens recognized by human tumour-reactive Tlymphocytes have been identified, and tetramer technology provided a means to demonstrate that these T-lymphocytes are present in cancer patients. Whether they fight an active battle against resident cancer cells or whether they have been rendered inactive by the tumour and by regulatory cells remains to be determined. Indeed, regulatory CD4 T-cells and natural killer T-cells have been shown to interfere with effective tumour immunity in animal models. The
knowledge of T-cell-recognized tumour antigens, together with a better understanding of the interplay between regulatory and effector cells of the immune system, provides hope for the design of effective antigen-specific immunotherapy protocols for the treatment of cancer.
