[Development of innovative T-cell immunotherapy for hematological malignancies]

With the emergence of cancer immunotherapy, T cells have played important roles in inducing antitumor responses. Many types of antitumor receptors, which possess tumor-binding sites and T-cell activation sites, have been developed. For example, genetically engineered T-cell receptor, chimeric antigen receptor, and bispecific antibody can help us to educate and activate T cells specific for certain tumors. To generate optimal antitumor receptors, (1) selection/distribution of tumor antigens, (2) affinity/specificity and cross-reactivity of antitumor receptors, and (3) T-cell activation signals delivered from antitumor receptors should be considered. Accordingly, we explain how antitumor receptors recognize target antigens and summarize the mechanisms for on-target/off-target reactivity induced by T cells redirected with antitumor receptors. Furthermore, we discuss how antitumor receptors can be optimized for the development of next-generation cancer immunotherapy.