HTLV-1 (Human T-cell lymphotropic virus type 1) is a complex human delta retrovirus that
currently infects 10–20 million people worldwide. While HTLV-1 infection is generally
asymptomatic, 3%–5% of infected individuals develop a highly malignant and intractable T-
cell neoplasm known as adult T-cell leukemia/lymphoma (ATL) decades after infection. How
HTLV-1 infection progresses to ATL is not well understood. Two viral regulatory proteins,
Tax and HTLV-1 basic zipper protein (HBZ), encoded by the sense and antisense viral …