Issues

In this issue, Keisuke Kataoka and colleagues map the trajectory of adult T-cell leukemia/lymphoma (ATL) development driven by HTLV-1 infection in a large cohort of ATL patients, asymptomatic HTLV-1 carriers, and healthy controls. The study maps at single-cell resolution the cellular ecosystem populating the systemic immune landscape. It identifies biologically and clinically relevant cues to navigate this high-dimensional space, including phenotypic hallmark of premalignant clonal expansion. By tracking clonal evolution of the infected T cells toward malignancy, the authors reveal that the neoplastic transformation develops hand in hand with alterations in the noninfected lymphoid and myeloid compartments, including PD-L1 protein transfer from malignant T cells to their neighbors. For details, please see the article on page 450.