Molecular targeting for treatment of human T-lymphotropic virus type 1 infection

Human T-cell lymphotropic virus type 1 (HTLV-1) infection is linked to adult T-cell leukemia-lymphoma (ATLL) and HTLV-I-associated myelopathy/tropical spastic paraparesis (HAM/TSP) and several other disorders. ATLL occurs in approximately 5% of the 15-20 million people infected by HTLV-1 in the world. In general, ATLL is resistant to chemotherapy, which underlines the need for new and effective therapeutic strategies. Previous studies highlighted the role of viral enzymes, responsible for viral replication, and regulatory proteins such as Tax and HBZ in the progression of HTLV-1-associated diseases. There are conflicting reports on the efficacy of current enzyme inhibitors, mainly developed against human immunodeficiency virus (HIV), for treatment of HTLV-1 infection. New treatment approaches including monoclonal antibodies show promising results and exert significant cytotoxic effects on ATLL cells. This manuscript reviews the recent developments in molecular targeting for treatment of HTLV-1 infection.