[Immunotherapy: new insights]

Immunotherapy of cancer, autoimmune diseases, and chronic viral infections is still in the early stages of development. This review deals with new immunotherapeutic approaches against tumors. Until now, a variety of specific and unspecific immunostimulatory strategies have been applied with only modest clinical success. The molecular characterization of novel human tumor antigens and the increased understanding of the immunological pathways involved in tumor immunity, however, have paved the way for the design of promising gene-based cellular cancer immune vaccines. Tumor antigens are readily available now and several ways to deliver antigen have been developed. The most important and widely used approaches consist of whole-cell vaccines, dendritic cell-based immunotherapy, and peptide vaccines. Clinical trials have, in general, demonstrated the safety of such strategies. There is, however, an important lack of information regarding to the correlation of clinical responses and analysis of the antitumoral immune effectors. Recently, exciting new immunological techniques and tools have been developed which allow to characterize antigen specific T cells at a single-cell level. In future, tumor rejection antigens have to be identified using new approaches such as reverse immunology which can be targeted therapeutically. A better quality control of the different immunotherapeutic approaches is mandatory if used in patients and the different therapeutic modalities need to be compared directly. This standardization of immunotherapeutic clinical trials may allow the identification of patient sub-groups responding favourably to treatment. The precise definition of immune parameters will ultimately result in optimised therapeutic approaches. Finally, the identification of antigen specific T and B cells by new assessment tools may result in novel surrogate markers for clinical diagnostic immunotherapy.