title: Spontaneous proliferation of memory (CD45RO+) and naive (CD45RO-) subsets of CD4 cells and CD8 cells in human T lymphotropic virus (HTLV) infection: distinctive patterns for HTLV-I versus HTLV-II.
abstract: Spontaneous lymphocyte proliferation (SLP) in vitro is a characteristic feature of about 50% of individuals infected with HTLV-I or HTLV-II. Both CD4 cells and CD8 cells contribute to SLP in HTLV-I infection, whereas SLP in HTLV-II infection is usually restricted to CD8 cells. In this study, we asked if SLP was restricted to the memory (CD45RO+) cell subset of CD4 and CD8 cells in HTLV infection. Purified CD4 and CD8 cells were separated into CD45RO+ and CD45RO- populations by a modified panning technique, and spontaneous proliferation (SP) of the cell subsets was assessed. For all five HTLV-I-infected persons whose mononuclear cell cultures were SLP+, only CD45RO+ cells, but not CD45RO- cells, within CD4 and CD8 subsets showed SP. In contrast, five of six SLP+ HTLV-II+ individuals showed SP in both the CD45RO+ and the CD45RO- subsets of CD4 cells, and 10 of 12 SLP+ HTLV-II+ individuals showed SP of both the CD45RO+ and CD45RO- subsets of CD8 cells. Polymerase chain reaction studies showed that proviral genome was generally present in both CD45RO+ and CD45RO- subsets of CD4 and CD8 cells, regardless of HTLV type and SP activity. These findings show that SP of both CD4 and CD8 cells in HTLV-I infection is usually restricted to CD45RO+ memory cells, whereas in HTLV-II infection, both CD45RO+ memory and CD45RO- naive subsets of CD4 and CD8 cells may exhibit SP. It thus appears that HTLV-I infection and HTLV-II infection exhibit distinctive dysregulatory effects on memory and naive T cell subpopulations.
authors.affiliation: American Red Cross Blood Services, Southern California Region, Los Angeles.
authors.forename: H E
authors.initials: HE
authors.lastname: Prince
authors.forename: J
authors.initials: J
authors.lastname: York
authors.forename: S M
authors.initials: SM
authors.lastname: Owen
authors.forename: R B
authors.initials: RB
authors.lastname: Lal
mesh_terms: D015496:CD4-Positive T-Lymphocytes / Q000276:immunology*; D018414:CD8-Positive T-Lymphocytes / Q000276:immunology*; D005434:Flow Cytometry; D015490:HTLV-I Infections / Q000276:immunology*; D015491:HTLV-II Infections / Q000276:immunology*; D015368:Human T-lymphotropic virus 1 / Q000276:immunology*; D015367:Human T-lymphotropic virus 2 / Q000276:immunology*; D006801:Humans; D007156:Immunologic Memory; D017493:Leukocyte Common Antigens / Q000378:metabolism*; D008213:Lymphocyte Activation; D016176:T-Lymphocyte Subsets / Q000276:immunology*
chemical_list: D017493:Leukocyte Common Antigens