Low CD4 T-cell counts despite low levels of circulating HIV: Insights from the comparison of HIV-1 infected patients with a discordant response to antiretroviral therapy to patients with untreated advanced HIV-2 disease

Benveniste, 2005, Mechanisms involved in the low-level regeneration of CD4+ cells in HIV-1-infected patients receiving highly active antiretroviral therapy who have prolonged undetectable plasma viral loads, J. Infect. Dis., 191, 1670, 10.1086/429670 Marziali, 2006, T-cell homeostasis alteration in HIV-1 infected subjects with low CD4 T-cell count despite undetectable virus load during HAART, AIDS, 20, 2033, 10.1097/01.aids.0000247588.69438.fd Aiuti, 2006, Failure to reconstitute CD4+ T-cells despite suppression of HIV replication under HAART, AIDS Rev., 8, 88 Renaud, 1999, Determinants of paradoxical CD4 cell reconstitution after protease inhibitor-containing antiretroviral regimen, AIDS, 13, 669, 10.1097/00002030-199904160-00007 Kaufmann, 2002, The extent of HIV-1-related immunodeficiency and age predict the long-term CD4 T lymphocyte response to potent antiretroviral therapy, AIDS, 16, 359, 10.1097/00002030-200202150-00007 Florence, 2003, Factors associated with a reduced CD4 lymphocyte count response to HAART despite full viral suppression in the EuroSIDA study, HIV Med., 4, 255, 10.1046/j.1468-1293.2003.00156.x Goicoechea, 2006, Determinants of CD4+ T cell recovery during suppressive antiretroviral therapy: association of immune activation, T cell maturation markers, and cellular HIV-1 DNA, J. Infect. Dis., 194, 29, 10.1086/504718 Piketty, 2001, Long-term clinical outcome of human immunodeficiency virus-infected patients with discordant immunologic and virologic responses to a protease inhibitor-containing regimen, J. Infect. Dis., 183, 1328, 10.1086/319861 Grabar, 2000, Clinical outcome of patients with HIV-1 infection according to immunologic and virologic response after 6 months of highly active antiretroviral therapy, Ann. Intern. Med., 133, 401, 10.7326/0003-4819-133-6-200009190-00007 Sousa, 2002, CD4 T cell depletion is linked directly to immune activation in the pathogenesis of HIV-1 and HIV-2 but only indirectly to the viral load, J. Immunol., 169, 3400, 10.4049/jimmunol.169.6.3400 Jaffar, 1997, Rate of decline of percentage CD4+ cells is faster in HIV-1 than in HIV-2 infection, J. Acquir. Immune Defic. Syndr. Human Retrovirol., 16, 327, 10.1097/00042560-199712150-00003 Marlink, 1994, Reduced rate of disease development after HIV-2 infection as compared to HIV-1, Science, 265, 1587, 10.1126/science.7915856 Berry, 1998, Low peripheral blood viral HIV-2 RNA in individuals with high CD4 percentage differentiates HIV-2 from HIV-1 infection, J. Hum. Virol., 1, 457 Popper, 2000, Low plasma human immunodeficiency virus type 2 viral load is independent of proviral load: low virus production in vivo, J. Virol., 74, 1554, 10.1128/JVI.74.3.1554-1557.2000 Soriano, 2000, Human immunodeficiency virus type 2 (HIV-2) in Portugal: clinical spectrum, circulating subtypes, virus isolation, and plasma viral load, J. Med. Virol., 61, 111, 10.1002/(SICI)1096-9071(200005)61:1<111::AID-JMV18>3.0.CO;2-W Damond, 2002, Plasma RNA viral load in human immunodeficiency virus type 2 subtype A and subtype B infections, J. Clin. Microbiol., 40, 3654, 10.1128/JCM.40.10.3654-3659.2002 Soares, 2006, Increased frequency of circulating CCR5+ CD4+ T cells in human immunodeficiency virus type 2 infection, J. Virol., 80, 12425, 10.1128/JVI.01557-06 Macneil, 2007, Direct evidence of lower viral replication rates in vivo in HIV-2 infection than in HIV-1 infection, J. Virol., 5325, 10.1128/JVI.02625-06 Simon, 1993, Cellular and plasma viral load in patients infected with HIV-2, AIDS, 7, 1411, 10.1097/00002030-199311000-00002 Kanki, 1994, Slower heterosexual spread of HIV-2 than HIV-1, Lancet, 343, 943, 10.1016/S0140-6736(94)90065-5 O'Donovan, 2000, Maternal plasma viral RNA levels determine marked differences in mother-to-child transmission rates of HIV-1 and HIV-2 in The Gambia. MRC/Gambia Government/University College London Medical School working group on mother-child transmission of HIV, AIDS, 14, 441, 10.1097/00002030-200003100-00019 Sousa, 2001, Comparison of the frequency of interleukin-2, interferon-g and interleukin-4 producing T cells in two diseases with distinct clinical outcomes: the human immunodeficiency virus type 1 and 2 infections, J. Infect. Dis., 184, 552, 10.1086/322804 Albuquerque, 2007, Rate of increase in Circulating IL-7 and loss of IL-7R{alpha} expression differ in HIV-1 and HIV-2 infections: two lymphopenic diseases with similar hyperimmune activation but distinct outcomes, J. Immunol., 178, 3252, 10.4049/jimmunol.178.5.3252 Champagne, 2001, Skewed maturation of memory HIV-specific CD8 T lymphocytes, Nature, 410, 106, 10.1038/35065118 Ariyoshi, 1996, A community-based study of human immunodeficiency virus type 2 provirus load in rural village in West Africa, J. Infect. Dis., 173, 245, 10.1093/infdis/173.1.245 Gomes, 1999, Quantitation of human immunodeficiency virus type 2 DNA in peripheral blood mononuclear cells by using a quantitative-competitive PCR assay, J. Clin. Microbiol., 37, 453, 10.1128/JCM.37.2.453-456.1999 Vitone, 2005, Quantitative DNA proviral detection in HIV-1 patients treated with antiretroviral therapy, J. Clin. Virol., 33, 194, 10.1016/j.jcv.2004.11.003 Fry, 2005, The many faces of IL-7: from lymphopoiesis to peripheral T cell maintenance, J. Immunol., 174, 6571, 10.4049/jimmunol.174.11.6571 Napolitano, 2001, Increased production of IL-7 accompanies HIV-1-mediated T-cell depletion: implications for T-cell homeostasis, Nat. Med., 7, 73, 10.1038/83381 Llano, 2001, Interleukin-7 in plasma correlates with CD4 T-cell depletion and may be associated with emergence of syncytium-inducing variants in human immunodeficiency virus type 1-positive individuals, J. Virol., 75, 10319, 10.1128/JVI.75.21.10319-10325.2001 Mazzucchelli, 2007, Interleukin-7 receptor expression: intelligent design, Nat. Rev., Immunol., 7, 144, 10.1038/nri2023 Schluns, 2000, Interleukin-7 mediates the homeostasis of naive and memory CD8 T cells in vivo, Nat. Immunol., 1, 426, 10.1038/80868 Grossman, 2002, CD4+ T-cell depletion in HIV infection: are we closer to understanding the cause?, Nat. Med., 8, 319, 10.1038/nm0402-319 Hazenberg, 2003, Persistent immune activation in HIV-1 infection is associated with progression to AIDS, AIDS, 17, 1881, 10.1097/00002030-200309050-00006 Deeks, 2004, Immune activation set point during early HIV infection predicts subsequent CD4+ T-cell changes independent of viral load, Blood, 104, 942, 10.1182/blood-2003-09-3333 Hunt, 2003, T cell activation is associated with lower CD4+ T cell gains in human immunodeficiency virus-infected patients with sustained viral suppression during antiretroviral therapy, J. Infect. Dis., 187, 1534, 10.1086/374786 Giorgi, 1993, Elevated levels of CD38+ CD8+ T cells in HIV infection add to the prognostic value of low CD4+ T cell levels: results of 6 years of follow-up. The Los Angeles Center, Multicenter AIDS Cohort Study, J. Acquir. Immune Defic. Syndr., 6, 904 Giorgi, 1994, CD8+ lymphocyte activation at human immunodeficiency virus type 1 seroconversion: development of HLA-DR+ CD38− CD8+ cells is associated with subsequent stable CD4+ cell levels. The Multicenter AIDS Cohort Study Group, J. Infect. Dis., 170, 775, 10.1093/infdis/170.4.775 Roederer, 1995, CD8 naive T cell counts decrease progressively in HIV-infected adults, J. Clin. Invest., 95, 2061, 10.1172/JCI117892 Torti, 2004, Immune correlates of virological response in HIV-positive patients after highly active antiretroviral therapy (HAART), Viral. Immunol., 17, 279, 10.1089/0882824041310630 Marchetti, 2006, Comparative analysis of T-cell turnover and homeostatic parameters in HIV-infected patients with discordant immune-virological responses to HAART, AIDS, 20, 1727, 10.1097/01.aids.0000242819.72839.db Andersson, 1998, Early reduction of immune activation in lymphoid tissue following highly active HIV therapy, AIDS, 12, F123, 10.1097/00002030-199811000-00004 Sloand, 1999, Human immunodeficiency virus type 1 protease inhibitor modulates activation of peripheral blood CD4(+) T cells and decreases their susceptibility to apoptosis in vitro and in vivo, Blood, 94, 1021, 10.1182/blood.V94.3.1021.415k29_1021_1027