Changes

==History==

==History==

In 1983, Barre-Sinoussi, Chermann, and Montagnier (at the Pasteur Institute in Paris) isolated a retrovirus from lymph node cells of a patient with lymphadenopathy; accordingly, this virus was designated lymphadenopathy-associated virus (LAV).  Lymphadenopathy-associated virus was shown to replicate and cause cytopathology in cultures of human peripheral blood lymphocytes.  A year after the report on LAV, Gallo and co-workers (at the National Institutes of Health, Bethesda, MD) described the isolation of a cytopathic T-lymphotropic retrovirus, designated human T-lymphotropic virus type III (HTLV-III), from peripheral blood lymphocytes of patients with acquired immunodeficiency syndrome (AIDS)<ref>Gallo RC, Salahuddin SZ, Propovic M, et al. Frequent detection and isolation of cytopathic retroviruses (HTLV-II) from patients with AIDS and at risk for AIDS. ''Science'' 1984;224:500-503.</ref>  Although this HTLV-III isolate was later shown to be a contaminant of virus from the Pasteur Institute<ref>Bryant ML, Yamamoti J, Luciw P, Munn R, Marx P, Higgins J, Pedersen N, Levine A, gardner MB, Molecular comparison of retroviruses associated with human and simian AIDS. ''Hematol Oncol'' 1985;3:187-197.</ref><ref>Chang SYP, Bowman BH, Weiss JB, Garcia RE, White TJ. The origin of HIV-1 isolate HTLV-IIIB. ''Nature'' 1993;363:466-469.</ref><ref>Wain-Hobson S, Vartanian JP, Henry M, Chenciner N, Cheynier R, Delassus S, Martins LP, Sala M, Nugeyre MT, Guetard D. LAV revisited: origins of the early HIV-1 isolates from Institut Pasteur. ''Science'' 1991;252:961-965.</ref>, subsequent isolates of HTLV-III were unique<ref>Hahn BH, Gonda MA, Shaw GM, Popovic M, Hoxie JA, Gallo RC, Wong-Staal F. Genomic diversity of the acquired immune deficiency syndrome virus HTLV-III: different viruses exhibit greatest divergence in their envelope genes.  Proc Natl Acad Sci USA 1985;82:4813-4817.</ref>.  Also, in 1984, Levy and co-workers (at the University of California, San Francisco) cultured an AIDS-associated retrovirus (ARV) from peripheral blood mononuclear cells of an AIDS patient<ref>Levy JA, Hoffman AD, Kramer SM, Landis JA, Shimabukuro JM, Oshiro LS. Isolation of lymphocytopathic retroviruses from San Francisco patients with AIDS. Science 1984;225:840-842</ref>.

In 1983, Barre-Sinoussi, Chermann, and Montagnier (at the Pasteur Institute in Paris) isolated a retrovirus from lymph node cells of a patient with lymphadenopathy; accordingly, this virus was designated lymphadenopathy-associated virus (LAV).  Lymphadenopathy-associated virus was shown to replicate and cause cytopathology in cultures of human peripheral blood lymphocytes.  A year after the report on LAV, Gallo and co-workers (at the National Institutes of Health, Bethesda, MD) described the isolation of a cytopathic T-lymphotropic retrovirus, designated human T-lymphotropic virus type III (HTLV-III), from peripheral blood lymphocytes of patients with acquired immunodeficiency syndrome (AIDS)<ref>Gallo RC, Salahuddin SZ, Propovic M, et al. Frequent detection and isolation of cytopathic retroviruses (HTLV-II) from patients with AIDS and at risk for AIDS. ''Science'' 1984;224:500-503.</ref>  Although this HTLV-III isolate was later shown to be a contaminant of virus from the Pasteur Institute<ref>Bryant ML, Yamamoti J, Luciw P, Munn R, Marx P, Higgins J, Pedersen N, Levine A, gardner MB, Molecular comparison of retroviruses associated with human and simian AIDS. ''Hematol Oncol'' 1985;3:187-197.</ref><ref>Chang SYP, Bowman BH, Weiss JB, Garcia RE, White TJ. The origin of HIV-1 isolate HTLV-IIIB. ''Nature'' 1993;363:466-469.</ref><ref>Wain-Hobson S, Vartanian JP, Henry M, Chenciner N, Cheynier R, Delassus S, Martins LP, Sala M, Nugeyre MT, Guetard D. LAV revisited: origins of the early HIV-1 isolates from Institut Pasteur. ''Science'' 1991;252:961-965.</ref>, subsequent isolates of HTLV-III were unique<ref>Hahn BH, Gonda MA, Shaw GM, Popovic M, Hoxie JA, Gallo RC, Wong-Staal F. Genomic diversity of the acquired immune deficiency syndrome virus HTLV-III: different viruses exhibit greatest divergence in their envelope genes.  Proc Natl Acad Sci USA 1985;82:4813-4817.</ref>.  Also, in 1984, Levy and co-workers (at the University of California, San Francisco) cultured an AIDS-associated retrovirus (ARV) from peripheral blood mononuclear cells of an AIDS patient<ref>Levy JA, Hoffman AD, Kramer SM, Landis JA, Shimabukuro JM, Oshiro LS. Isolation of lymphocytopathic retroviruses from San Francisco patients with AIDS. Science 1984;225:840-842</ref>.  Molecular cloning and sequence analysis revealed that the genomes of LAV and HTLV-III were nearly identical, exhibiting 1% to 2% divergence.  In contrast, the genome of the ARV-2 isolate displayed up to 15% differences in nucleotide sequences in pairwise alignments with the genomes of either LAV or HTLV-III.  Electron microscopy demonstrated that these viruses from AIDS patients were morphologically similar to members of the lentivirus genus of the family ''Retroviridae''.  Furthermore, comparison of genome sequences also supported the notion that the human retroviruses associated with AIDS were related, albeit distantly, to lentiviruses of other animals.

== Transmission ==

== Transmission ==