Immunological aspects of HTLV-1 persistence; for the prevention and treatment of Adult T-cell leukaemia-lymphoma (ATL).

Human T-cell leukaemia virus type-1 (HTLV-1) causes the highly aggressive malignancy adult T-cell leukaemia-lymphoma (ATL) in approximately 5 % of chronically infected carriers. HTLV-1 persists in the host by enhancing survival of infected-T-cells despite the presence of a strong immune response. Therefore, asymptomatic HTLV-1 carriers have a lifelong balance between infected cell proliferation and the host antiviral immune response. However, this immunological balance is lost in patients with ATL. Reliable treatment options are lacking and there is urgent need for new treatment strategies to improve the dismal prognosis of ATL. In this review, we present a summary of the current knowledge on the immunological aspects of HTLV-1 persistence and the immune alterations observed in ATL, and discuss how the recent emerging advances in adoptive immunotherapy may offer a prevention and treatment option for ATL.