A long latency period from HTLV-1 infection to ATL onset suggests that not only HTLV-1 proteins, such as Tax and HBZ, but also additional genetic and/or epigenetic events are required for ATL development.
Our results identify the cytoplasmic localization of HBZ in HAM/TSP patient as a possible biomarker of this rather neglected tropical disease, and raise important hypotheses on the role of HBZ in the pathogenesis of the neuromyelopathy associated to HTLV-1 infection.
Hence, during HTLV-1 infection, when Tax/Rex expression is robust and dominant over HBZ, productive infection ensues with expression of structural proteins and NF-κB hyper-activation, which induces senescence.