       Document 0593
 DOCN  M9550593
 TI    Syncytium-inducing (SI) phenotype suppression at seroconversion after
       intramuscular inoculation of a non-syncytium-inducing/SI phenotypically
       mixed human immunodeficiency virus population.
 DT    9505
 AU    Cornelissen M; Mulder-Kampinga G; Veenstra J; Zorgdrager F; Kuiken C;
       Hartman S; Dekker J; van der Hoek L; Sol C; Coutinho R; et al; Human
       Retrovirus Laboratory, Academic Medical Centre, Amsterdam,; The
       Netherlands.
 SO    J Virol. 1995 Mar;69(3):1810-8. Unique Identifier : AIDSLINE
       GENBANK/Z47540
 AB    Two distinct biological phenotypes of human immunodeficiency virus (HIV)
       have been described: the non-syncytium-inducing (NSI) phenotype, best
       characterized by the inability to infect MT-2 cells, and the
       syncytium-inducing (SI) phenotype, with the ability to infect MT-2
       cells. The earliest virus population observed following HIV transmission
       is generally of the NSI phenotype, even after exposure to inocula of
       mixed NSI/SI phenotype. In this study, the issue of intrapatient
       selection of virus phenotype following transmission was addressed by
       studying two cases of accidental transmission. A comparison of the
       sequences of the V1-V2 and the V3 coding regions of the envelope gene
       and the p17 region of the gag gene showed that the donor-recipient pairs
       were tightly clustered in all gene segments, but away from local and
       published transmission controls. The intrasample variation of the p17
       sequence was greater in the recipients and smaller in the donors than
       that of the V3 region sequence, indicating selection of V3 at
       transmission. In these transmission cases, the effects of an intravenous
       inoculation of a small quantity of blood containing predominantly SI V3
       sequences (6 of 8 clonal sequences) were compared with those of an
       intramuscular inoculation of a large quantity of blood containing
       predominantly NSI viruses (14 of 16 clonal sequences). Both SI and NSI
       V3 regions were demonstrated to be phenotypic expressions of genetically
       related viral strains. The inoculation of the predominantly SI virus
       population resulted in the persistence of an SI virus population in the
       recipient and a rapid CD4+ T-cell decline. The inoculation of the
       predominantly NSI population resulted in a selective amplification of SI
       viruses before seroconversion, followed by a suppression of SI viruses
       at seroconversion and a rapid decline of CD4+ T-cell numbers. These data
       suggest that the suppression of SI viruses can be accomplished following
       the development of HIV-specific immunity and that the ability to
       suppress SI viruses does not prevent the development of
       immunodeficiency.
 DE    Acquired Immunodeficiency Syndrome/TRANSMISSION  Adult  Amino Acid
       Sequence  Base Sequence  Case Report  Cell Fusion  Comparative Study
       Consensus Sequence  DNA Primers/CHEMISTRY  Female  Genes, env  Genes,
       gag  Human  HIV Envelope Protein gp120/GENETICS  HIV
       Seropositivity/*MICROBIOLOGY  HIV-1/GENETICS/*PATHOGENICITY  Molecular
       Sequence Data  Phylogeny  RNA, Viral/GENETICS  Sequence Alignment
       Sequence Homology, Amino Acid  Support, Non-U.S. Gov't  Time Factors
       Variation (Genetics)  JOURNAL ARTICLE

       SOURCE: National Library of Medicine.  NOTICE: This material may be
       protected by Copyright Law (Title 17, U.S.Code).

