During the last decade, a large number of human tumor-associated antigens have been identified that are recognized by CTLs in a MHC-restricted fashion. The apoptosis inhibitor protein survivin is overexpressed in most human cancers, and inhibition of its function results in increased apoptosis. Therefore, this protein may serve as a target for therapeutic CTL responses. Here, using CTL epitopes deduced from survivin, we describe specific T-cell reactivity against this antigen in peripheral blood from chronic lymphatic leukemia patients and in tumor-infiltrated lymph nodes from melanoma patients by ELISPOT analysis. CTL responses against two survivin-deduced peptide epitopes were detected in three of six melanoma patients and three of four chronic lymphatic leukemia patients. No T-cell reactivity was detected in peripheral blood lymphocytes from six healthy controls. Thus,survivin may serve as an important and widely applicable target for anticancer immunotherapeutic strategies.