Immunotherapeutic strategies are pivotal for cancer treatment. T-cells form the most important part of the specific immune response against malignant cells. T-cell based therapies have made great progress during the last years. The unspecfic immune therapy by so-called checkpoint inhibition has been established as an important pillar of the tumor therapy. Therapies with T-cells of defined specificities against tumor-associated target proteins have reached clinical practice for the treatment of leukemia and lymphoma.

For checkpoint inhibition antibodies are used to block receptors, by which tumors are able to inactivate potentially otherwise efficient specific T-cell responses. Most important current activities in clinical and pre-clinical research are the development of new target receptors, the combination of different treatment strategies and the identification of predictive markers for response of such therapies.

Targeted T-cell therapy is based on T-cells, which are able to recognize tumor-specific proteins. Currently, research focuses on the production and use of genetic modified T-cells, which gain tumor-specificity by introduction of a second, tumor-specific T-cell receptor. Alternatively, T-cells can become tumor-specific by introduction of a chimeric antigen receptor (CAR), which contains parts of antibodies and receptors. With such CAR, T-cells can be activated by surface proteins like receptors on malignant cells. Until now CAR- based therapies  are mainly used in leukemias and lymphomas, but might also have potential in solid malignancies