Role of HTLV-1 orf-I encoded proteins in viral transmission and persistence

The human T cell leukemia virus type 1 (HTVL-1), first reported in 1980 by Robert Gallo’s group, is the etiologic agent of both cancer and inflammatory diseases. Despite approximately 40 years of investigation, the prognosis for afflicted patients remains poor with no effective treatments. The virus persists in the infected host by evading the host immune response and inducing proliferation of infected CD4+T-cells. Here, we will review the role that viralorf-Iprotein products play in altering intracellular signaling, protein expression and cell–cell communication in order to escape immune recognition and promote T-cell proliferation. We will also review studies oforf-Imutations found in infected patients and their potential impact on viral load, transmission and persistence. Finally, we will compare theorf-Igene in HTLV-1 subtypes as well as related STLV-1.