Towards defining specific antigens for cutaneous lymphomas

Cutaneous lymphomas (CLs) are a heterogeneous group of malignancies of T-cell (cutaneous T-cell lymphoma, CTCL) or B-cell (cutaneous B-cell lymphoma, CBCL) origin with primary manifestation in the skin. CLs are difficult to treat in their advanced stages, especially as there is no curative treatment available. Immunological therapies might be a promising alternative, but the prerequisite for such strategies is the knowledge of tumor-specific antigens. This paper is reviewing the methods used today for identifying such antigens with special respect to CLs. The most successful strategies for the discovery of new tumor antigens include the cytotoxic T-cell approach using either genetic or biochemical tools, or synthetic peptide libraries leading to so-called mimotopes. A second strategy utilizes antibodies for screening recombinant libraries: either monoclonal antibodies generated against tumor cells or the so-called SEREX approach using antibodies of the patient's serum. Especially the antibody-based strategies led to several new antigens expressed in CTCL. Finally, already known tumor antigens have been evaluated as possible targets for CLs. A growing list of tumor antigens can be summarized for CLs, especially CTCL, which include cTAGE-1, SCP-1, GBP-TA, several mimotopes, SC5, LAGE-1, and NY-ESO-1, as well as the GAGE and MAGE-A groups. Perspectives on basis of the present knowledge are discussed.