Cell-mediated immune response to human T-lymphotropic virus type I.
Human T-lymphotropic virus type I (HTLV-I) is a retrovirus that causes persistent infection in many populations in tropical and subtropical regions. HTLV-I chronically activates the cell-mediated arm of the host adaptive immune response. There has been much debate about the role of the immune response in determining the outcome of HTLV-I infection: most seropositive individuals remain lifelong asymptomatic carriers of the virus, whereas a small proportion-usually those with higher equilibrium proviral loads-develop an inflammatory disease of the central nervous system known as HAM/TSP. Here we discuss the cell-mediated immune response to HTLV-I infection. We summarize recent data on the HTLV-I-specific CD4(+) cell response and explore its potential role in HAM/TSP pathogenesis. We also explore the controversy surrounding the role of the CD8(+) cell response in controlling HTLV-I infection and/or contributing to HAM/TSP disease, highlighting recent studies of T cell gene expression profiles and a newly developed assay of CD8(+) cell functional efficiency. Finally, we introduce a possible role for cellular innate immune effectors in HTLV-I infection.
Mosley
Angelina J
AJ
Department of Immunology, Imperial College London, London, United Kingdom.
Asquith
Becca
B
Bangham
Charles R M
CR
D015496:CD4-Positive T-Lymphocytes / Q000276:immunology*; D018414:CD8-Positive T-Lymphocytes / Q000276:immunology*; D015490:HTLV-I Infections / Q000276:immunology / Q000821:virology; D015368:Human T-lymphotropic virus 1 / Q000276:immunology / Q000472:pathogenicity*; D006801:Humans; D015493:Paraparesis, Tropical Spastic / Q000276:immunology* / Q000503:physiopathology* / Q000821:virology