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tipranavir.tipranavir is a newly approved protease inhibitor that belongs to the class of 4-hydroxy-5,6-dyhydro-2-pyrones. it exhibits potent in vitro activity against both human immunodeficiency virus (hiv)-1 and hiv-2, including clinical isolates with multiple protease inhibitor-resistant mutations. tipranavir requires coadministration with ritonavir to achieve clinically meaningful serum concentration. in randomized, phase iii, open-label trials, it was found to be superior to the currently available bo ...200516395412
natural resistance of human immunodeficiency virus type 2 to zidovudine.zidovudine (azt) is a reverse transcriptase (rt) inhibitor widely used to treat persons infected with hiv-1 and hiv-2. recent data on treated patients suggest differences in the antiviral activity of azt between hiv-1 and hiv-2. we evaluated the antiviral activity of azt on hiv-2 by using multiple approaches including in vitro selection experiments, analysis of growth kinetics with azt, and phenotypic testing. a total of 5 wild-type (wt) hiv-2 viruses were used in the analysis. for comparison, 4 ...200515892966
newborn liver gene transfer by an hiv-2-based lentiviral vector.newborn gene therapy, because it can prevent the damage caused by the onset of a disease, deserves specific attention. to evaluate gene transfer in tissues of newborn mice, we used a human immunodeficiency virus (hiv)-2 based lentiviral vector pseudotyped with vesicular stomatitis virus g glycoprotein expressing the green fluorescent protein reporter gene under the control of the cytomegalovirus promoter. we found that very low doses of hiv-2 could infect and be expressed in newborn mice. under ...200515772691
predictive value of soluble haemoglobin scavenger receptor cd163 serum levels for survival in verified tuberculosis patients.pre-treatment serum levels of scd163 were measured in a cohort of 236 suspected tuberculosis (tb) cases from guinea-bissau, with a median follow-up period of 3.3 years (range 0-6.4 years). in 113 cases, the diagnosis of tb was verified by positive sputum microscopy and/or culture. among the verified tb cases, a decreased survival rate was found in 27 patients with scd163 levels above the upper reference limit (3.95 microg/ml). the difference in survival was significant during tb treatment (log r ...200516104988
characterization of a long terminal repeat region from an infectious indian hiv type 2 isolate.an infectious indian human immunodeficiency virus type 2 isolate from mumbai, propagated in this laboratory, was found to bear an unusually short long terminal repeat (ltr) region. complete sequencing of the 601 bp ltr indicated a loss of around 250 nucleotide pairs from the unique 3' (u3) region as compared to other well-characterized hiv-2 isolates. phylogenetic analysis of this ltr shows closest relatedness to the guinea-bissau subtype a isolates hiv-2(cam2) and hiv-2(ali). the ltr from the b ...200515989467
duplication of peri-kappab and nf-kappab sites of the first human immunodeficiency virus type 2 (hiv-2) transmission in brazil.after the identification of hiv-2 in 1986, most of the cases reported have been concentrated in west africa. we identified a case of hiv-2 infection in são paulo, brazil of a 45-year-old female who presented with pneumocystis carinii pneumonia, with a cd4 count of 22 cells/ml. dna samples from this patient were subjected to end-point pcr amplification of the ltr region. clones were sequenced and subjected to phylogenetic analyses. all clones were subtype a related, and four presented an insertio ...200516386115
characterization of human immunodeficiency virus (hiv)-2 vector mobilization by hiv-1.conditionally replicating human immunodeficiency virus type 2 (crhiv-2) vectors can compete with hiv-1 for packaging in hiv-1-infected cells, indicating that the mobilization of vectors could selectively target as well as protect reservoirs susceptible to hiv-1 infection. the incorporation of hiv-1-specific antiviral transgenes in crhiv-2 vectors, although increasing the direct antiviral effect, may decrease mobilization and transmission to surrounding cells. to investigate how hiv-1-specific ca ...200516390277
divergent hiv and simian immunodeficiency virus surveillance, zaire.recent hiv infection or divergent hiv or simian immunodeficiency virus (siv) strains may be responsible for western blot-indeterminate results on 70 serum samples from zairian hospital employees that were reactive in an enzyme immunoassay. using universal polymerase chain reaction hiv-1, hiv-2, and siv primers, we detected 1 (1.4%) hiv-1 sequence. except for 1 sample, no molecular evidence for unusual hiv- or siv-like strains in this sampling was found.200516229778
cognitive and motor deficits associated with hiv-2(287) infection in infant pigtailed macaques: a nonhuman primate model of pediatric neuro-aids.lentivirus-infected nonhuman primates exhibit behavioral and neurological pathology similar to human immunodeficiency virus (hiv)-infected humans and offer a means to examine the effects of lentivirus infection while controlling for confounding factors inherent in human populations. the purpose of this study was to examine cognitive and motor development in infant macaques vertically infected with hiv-2287. subjects were 20 infant pigtail macaques (macaca nemestrina); 8 controls born to uninfect ...200515804957
antiviral potential of a new generation of acyclic nucleoside phosphonates, the 6-[2-(phosphonomethoxy)alkoxy]-2,4-diaminopyrimidines.three acyclic nucleoside phosphonates (anps) have been formally approved for clinical use in the treatment of 1) cytomegalovirus retinitis in aids patients (cidofovir, by the intravenous route), 2) chronic hepatitis b virus (hbv) infections (adefovir dipivoxil, by the oral route), and 3) human immunodeficiency virus (hiv) infections (tenofovir disoproxil fumarate, by the oral route). the activity spectrum of cidofovir {(s)- 1-[3-hydroxy-2-(phosphonomethoxy)propyl]cytosine [(s)-hpmpc)]}, like tha ...200516247948
a novel simian immunodeficiency virus from black mangabey (lophocebus aterrimus) in the democratic republic of congo.in order to understand primate lentivirus evolution, characterization of additional simian immunodeficiency virus (siv) strains is essential. here, an siv from a black mangabey (lophocebus aterrimus) originating from the democratic republic of congo was analysed phylogenetically. the monkey had cross-reactive antibodies against human immunodeficiency virus type 1 (hiv-1) and hiv-2. the viral pol region sequence was amplified by nested pcr and sequence analysis confirmed that it was related to kn ...200515958675
evolution of human immunodeficiency virus type 2 coreceptor usage, autologous neutralization, envelope sequence and glycosylation.to investigate why human immunodeficiency virus type 2 (hiv-2) is less virulent than hiv-1, the evolution of coreceptor usage, autologous neutralization, envelope sequence and glycosylation was studied in sequentially obtained virus isolates and sera from four hiv-2-infected individuals. neutralization of primary hiv-2 isolates was tested by a cell line-based assay and igg purified from patients' sera. significant autologous neutralization was observed for the majority (39 of 54) of the hiv-2 se ...200516298986
viral response to antiretroviral therapy in a patient coinfected with hiv type 1 and type 2.clinical experience with the treatment of human immunodeficiency virus (hiv) type 2 (hiv-2) infection is limited, and even more scarce is information on therapy for patients coinfected with hiv type 1 (hiv-1) and hiv-2. here, we describe the outcome for a coinfected patient in whom infection with both viruses was successfully controlled at the start of antiretroviral therapy, but for whom hiv-2 infection escaped control after a treatment simplification change while hiv-1 remained undetectable.200515983906
raman spectroscopic study on structure of human immunodeficiency virus (hiv) and hypericin-induced photosensitive damage of hiv.the first raman spectra of hiv1-hiv2 in human sera and hypericin-induced photosensitive damage of the virus have been obtained. the prominent raman lines in the spectra are assigned respectively to the carbohydrates of viral glycoprotein, rna, protein and lipid. the spectra are dominated by raman scattering of the carbohydrates. the lines of d-mannose and n-acetylglucosamine in carbohydrates are obvious and there is a beta-configuration in the anomeric c1 position in d-mannose. the viral rna dup ...200515986884
scorpion-toxin mimics of cd4 in complex with human immunodeficiency virus gp120 crystal structures, molecular mimicry, and neutralization breadth.the binding surface on cd4 for the hiv-1 gp120 envelope glycoprotein has been transplanted previously onto a scorpion-toxin scaffold. here, we use x-ray crystallography to characterize atomic-level details of gp120 with this transplant, cd4m33. despite known envelope flexibility, the conformation of gp120 induced by cd4m33 was so similar to that induced by cd4 that localized measures were required to distinguish ligand-induced differences from lattice variation. to investigate relationships betw ...200515893666
the promiscuous cc chemokine receptor d6 is a functional coreceptor for primary isolates of human immunodeficiency virus type 1 (hiv-1) and hiv-2 on astrocytes.the role of coreceptors other than ccr5 and cxcr4 in the pathogenesis of human immunodeficiency virus (hiv) disease is controversial. here we show that a promiscuous cc chemokine receptor, d6, can function as a coreceptor for various primary dual-tropic isolates of hiv type 1 (hiv-1) and hiv-2. furthermore, d6 usage is common among chimeric hiv-1 constructs bearing the gp120 proteins of isolates from early seroconverting patients. d6 mrna and immunoreactivity were demonstrated to be expressed in ...200516014924
inhibition of ccr5-mediated infection by diverse r5 and r5x4 hiv and siv isolates using novel small molecule inhibitors of ccr5: effects of viral diversity, target cell and receptor density.highly active anti-retroviral therapy (haart) has been very effective in reducing viral loads in human immunodeficiency virus (hiv)-1 patients. however, current therapies carry detrimental side effects, require complex drug regimes and are threatened by the emergence of drug-resistant variants. there is an urgent need for new anti-hiv drugs that target different stages of the replication cycle. several synthetic small organic molecules that inhibit hiv infection by binding to the ccr5 coreceptor ...200516157392
nef proteins from diverse groups of primate lentiviruses downmodulate cxcr4 to inhibit migration to the chemokine stromal derived factor 1.nef proteins of primate lentiviruses promote viral replication, virion infectivity, and evasion of antiviral immune responses by modulating signal transduction pathways and downregulating expression of receptors at the cell surface that are important for efficient antigen-specific responses, such as cd4, cd28, t-cell antigen receptor, and class i and class ii major histocompatibility complex. here we show that nef proteins from diverse groups of primate lentiviruses which do not require the chem ...200516051857
potential clinical applications of the cxcr4 antagonist bicyclam amd3100.the bicyclam amd3100 (originally called jm3100), in which the two cyclam rings are tethered by an aromatic bridge, emanated from jm2763, where the two cyclam moieties are tethered by an aliphatic linker - jm2763 in turn originated from jm1657, where the cyclam rings are directly linked to one another via a c-c bridge, and which was identified as an impurity, showing anti-hiv activity, in a commercial cyclam preparation. amd3100 proved very effective against hiv-1 and hiv-2, inhibiting virus repl ...200516178723
isolation of human immunodeficiency virus type 2 biological clones from peripheral blood lymphocytes.infectious variants of human immunodeficiency virus (hiv) can be isolated from peripheral blood mononuclear cells (pbmc) of infected individuals by propagating the virus in co-cultures with healthy donor pbmc. standardized culture protocols have been designed specifically for the isolation of hiv type 1 (hiv-1) and proven effective for the isolation of virus from virtually all hiv-1-infected individuals. for the isolation of hiv-2, however, standard hiv-1 culture protocols have been only partial ...200516061969
[evaluation of a panel of commercial kits for the detection of serum hiv-specific antibodies, and choice of alternative strategies for the serological diagnosis in libreville (gabon)].nine commercially available kits for the screening of serum antibodies to the human immunodeficiency virus (hiv) were evaluated with a panel of 170 serum samples from adults in gabon. the reference procedures showed that 96 samples had no antibodies, while 74 produced antibodies to hiv-1 (n=72) or hiv-2 (n=2). the sensitivity for 2 kits was less than 99% and the specificity of 3 less than 95%. based on the panel of gabonese serum samples, 4 of the 9 kits met the world health organization (who) a ...200515919629
detection of hiv-2 by pcr.genomes of human immunodeficiency virus type 2 (hiv-2), like those of hiv-1 or other retroviruses, are highly variable. these genetic variants have been classified into seven genetic subtypes. the average genetic divergence between different subtypes is about 20% in the gag gene, which is higher than those among hiv-1 group m subtypes. the current serological tests cannot distinguish the different subtypes from one another. to understand genetic variation, evolution, and subtype distribution of ...200516061976
amplification and cloning of near full-length hiv-2 genomes.the genomes of human immunodeficiency virus type 2 (hiv-2), like those of hiv-1, are not only extremely variable but are also highly recombinogenic. determination of subtypes based on partial genomes cannot predict the subtype classification of other regions of the genome owing to the frequent occurrence of recombinant genomes among subtypes. to fully understand the genetic variation and evolution of hiv-2s, full-length viral genomes need to be obtained for genetic analysis. full-length hiv-2 ge ...200516061992
polymorphism of the human immunodeficiency virus type 2 (hiv-2) protease gene and selection of drug resistance mutations in hiv-2-infected patients treated with protease inhibitors.we described the baseline polymorphism of the human immunodeficiency virus type 2 (hiv-2) protease gene from 94 treatment-naive patients and the longitudinal follow-up of 17 protease inhibitor-treated patients. compared to the hiv-2 consensus sequences, baseline polymorphism involved 47 positions. substitutions selected under treatment were observed at positions corresponding to hiv-1 resistance mutations as well as at positions of currently unknown impact on hiv-1.200515635022
polymorphism and drug-selected mutations in the reverse transcriptase gene of hiv-2 from patients living in southeastern france.few data are available about the susceptibility and the genotypic resistance pattern of human immunodeficiency virus type 2 (hiv-2) to nucleoside reverse transcriptase inhibitors (nrtis). the hiv-2 reverse transcriptase (rt) gene from 25 hiv-2-infected patients followed-up in marseilles and the surrounding area was analyzed. the aims of this study were to characterize the polymorphism of hiv-2 rt in the absence of drug, to determine whether it naturally harbors codons associated with drug-resist ...200515648062
detection and partial characterization of simian immunodeficiency virus sivsm strains from bush meat samples from rural sierra leone.human immunodeficiency virus type 2 (hiv-2) originated from simian immunodeficiency viruses (sivs) that naturally infect sooty mangabeys (sms; cercocebus atys). in order to further investigate the relationship between hiv-2 and sivsm, the siv specific to the sm, we characterized seven new sivsm strains from sms sold in sierra leone markets as bush meat. the gag, pol, and env sequences showed that, while the viruses of all seven sms belonged to the sivsm-hiv-2 lineage, they were highly divergent ...200515681464
mitochondrial dna and retroviral rna analyses of archival oral polio vaccine (opv chat) materials: evidence of macaque nuclear sequences confirms substrate identity.inoculation of live experimental oral poliovirus vaccines (opv chat) during the 1950s in central africa has been proposed to account for the introduction of hiv into human populations. for this to have occurred, it would have been necessary for chimpanzee rather than macaque kidney epithelial cells to have been included in the preparation of early opv materials. theoretically, this could have led to contamination with a progenitor of hiv-1 derived from a related simian immunodeficiency virus of ...200515705467
chimeric human immunodeficiency virus type 1 virions that contain the simian immunodeficiency virus nef gene are cyclosporin a resistant.we have previously shown that human immunodeficiency virus type 1 (hiv-1) virions which have their own nef gene deleted and are trans complemented to contain hiv-2 or simian immunodeficiency virus (siv) nef become resistant to treatment with cyclosporin a. to expand and confirm these studies, we have tested an hiv-1 isolate in which the hiv-1 nef gene has been replaced by the nef gene from siv in a multiround infectivity assay using more physiologically relevant cell types. our results confirm t ...200515709044
the vpr protein from hiv-1: distinct roles along the viral life cycle.the genomes of human and simian immunodeficiency viruses (hiv and siv) encode the gag, pol and env genes and contain at least six supplementary open reading frames termed tat, rev, nef, vif, vpr, vpx and vpu. while the tat and rev genes encode regulatory proteins absolutely required for virus replication, nef, vif, vpr, vpx and vpu encode for small proteins referred to "auxiliary" (or "accessory"), since their expression is usually dispensable for virus growth in many in vitro systems. however, ...200515725353
selective inhibition of hiv-1 reverse transcriptase-associated ribonuclease h activity by hydroxylated tropolones.high-throughput screening of a national cancer institute library of pure natural products identified the hydroxylated tropolone derivatives beta-thujaplicinol (2,7-dihydroxy-4-1(methylethyl)-2,4,6-cycloheptatrien-1-one) and manicol (1,2,3,4-tetrahydro-5-7-dihydroxy-9-methyl-2-(1-methylethenyl)-6h-benzocyclohepten-6-one) as potent and selective inhibitors of the ribonuclease h (rnase h) activity of human immunodeficiency virus-type 1 reverse transcriptase (hiv-1 rt). beta-thujaplicinol inhibited ...200515741178
the interaction of ledgf/p75 with integrase is lentivirus-specific and promotes dna binding.we have previously shown that the p75 isoform of the transcriptional co-activator lens epithelium-derived growth factor (ledgf) interacts tightly with human immunodeficiency virus (hiv)-1 integrase (in) and is essential for nuclear targeting of this protein in human cells (cherepanov, p., maertens, g., proost, p., devreese, b., van beeumen, j., engelborghs, y., de clercq, e., and debyser, z. (2003) j. biol. chem. 278, 372-381; maertens, g., cherepanov, p., pluymers, w., busschots, k., de clercq, ...200515749713
amino acid preferences for a critical substrate binding subsite of retroviral proteases in type 1 cleavage sites.the specificities of the proteases of 11 retroviruses representing each of the seven genera of the family retroviridae were studied using a series of oligopeptides with amino acid substitutions in the p2 position of a naturally occurring type 1 cleavage site (val-ser-gln-asn-tyr pro-ile-val-gln; the arrow indicates the site of cleavage) in human immunodeficiency virus type 1 (hiv-1). this position was previously found to be one of the most critical in determining the substrate specificity differ ...200515767422
viral dynamics of primary hiv-1 infection in senegal, west africa.few studies have addressed primary human immunodeficiency virus (hiv) type 1 infection in sub-saharan africa, where the epidemic is of a predominantly heterosexual character and is caused by different subtypes. the present study examines the dynamics of viral replication in subjects infected with various hiv-1 subtypes.200515809904
annulling a dangerous liaison: vaccination strategies against aids and tuberculosis.human immunodeficiency virus (hiv) and mycobacterium tuberculosis annually cause 3 million and 2 million deaths, respectively. last year, 600,000 individuals, doubly infected with hiv and m. tuberculosis, died. since world war i, approximately 150 million people have succumbed to these two infections--more total deaths than in all wars in the last 2,000 years. although the perceived threats of new infections such as sars, new variant creutzfeldt-jakob disease and anthrax are real, these outbreak ...200515812488
subtype & cytokine profiles of hiv infected individuals from south india.the global surveillance of human immunodeficiency virus (hiv) subtypes (clades) helps understand the global distribution and incidence of different hiv subtypes. as knowledge about subtypes circulating in an area is needed for developing a candidate vaccine, prevalence of the subtypes hiv-1 and hiv-2 were studied in south india. the profile of cytokines interleukin 10 (il10) and interferon gamma (ifngamma) in both types of infection were also analysed as these are considered indicators of diseas ...200515817940
inactivation of viruses in platelet concentrates by photochemical treatment with amotosalen and long-wavelength ultraviolet light.viral contamination of platelet (plt) concentrates can result in transfusion-transmitted diseases. a photochemical treatment (pct) process with amotosalen-hcl and long-wavelength ultraviolet light (uva), which cross-links nucleic acids, was developed to inactivate viruses and other pathogens in plt concentrates.200515819680
differential inhibition of hiv-1 and siv envelope-mediated cell fusion by c34 peptides derived from the c-terminal heptad repeat of gp41 from diverse strains of hiv-1, hiv-2, and siv.the spectrum of inhibition of human (hiv) and simian (siv) immunodeficiency virus envelope (env)-mediated cell fusion by c34, a 34 residue peptide corresponding to the c-heptad repeat of gp41 (residues 628-661 of hiv-1 env), has been examined using a panel of five envelope glycoproteins, three from hiv-1 (lav, sf162 and 89.6) and two from siv (mac239 and mac316), and six c34 peptides derived from three strains of hiv-1 (lav, n cm, and o cm), two strains of hiv-2 (eho and ali), and one strain of ...200515828842
spectrum of antiviral activity of o-(acetoxyphenyl)hept-2-ynyl sulphide (aphs).since some antiviral drugs have a broad spectrum of action, the aim of this study was to assess whether o-(acetoxyphenyl)hept-2-ynyl sulphide (aphs), a recently described inhibitor of human immunodeficiency virus type 1 (hiv-1) replication, has an effect on the replication of other retroviruses, (-) and (+) rna viruses and dna viruses. aphs did not affect the replication of feline immunodeficiency virus, hiv-2 and a hiv-1 strain resistant to non-nucleoside reverse transcriptase inhibitors (nnrti ...200515848298
no observed effect of gb virus c coinfection on disease progression in a cohort of african woman infected with hiv-1 or hiv-2.we studied mortality among subjects with human immunodeficiency virus (hiv)-1 and hiv-2 infection in relation to gb virus (gbv)-c coinfection. no significant differences in mortality were seen between subjects with and subjects without gbv-c coinfection who also had either hiv-1 or hiv-2 infection. no association between gbv-c and hiv plasma virus loads or cd4 cell count was observed.200515736023
cloning, expression, and purification of hiv-2 gp125: a target for hiv vaccination.the envelope of the human immunodeficiency virus (hiv) is the main target for neutralizing antibodies. we report the cloning, purification, and characterization of two recombinant forms of the envelope glycoprotein gp125 from a primary hiv-2sbl-6669 isolate. both constructs were truncated at the n- and c-termini, and in the gp125deltav1v2 construct the variable v1 and v2 loops were deleted. the recombinant glycoproteins were stably expressed in chinese hamster ovarian cells, producing soluble gp ...200515920286
rapid assessment of injection practices in cambodia, 2002.injection overuse and unsafe injection practices facilitate transmission of bloodborne pathogens such as hepatitis b virus (hbv), hepatitis c virus (hcv), and human immunodeficiency virus (hiv). anecdotal reports of unsafe and unnecessary therapeutic injections and the high prevalence of hbv (8.0%), hcv (6.5%), and hiv (2.6%) infection in cambodia have raised concern over injection safety. to estimate the magnitude and patterns of such practices, a rapid assessment of injection practices was con ...200515929800
modification of a viral envelope glycoprotein cell-cell fusion assay by utilizing plasmid encoded bacteriophage rna polymerase.many viruses enter cells via an interaction of the viral envelope glycoprotein (env) with receptor inducing fusion of viral and cellular membranes. these interactions are often evaluated in cell-cell fusion, gene-reporting systems with effector cells expressing env and target cells expressing receptors. a common system utilizes vaccinia virus encoding t7 rna polymerase (rnap) in effector cells and a t7 promoted reporter plasmid in target cells. fusion is quantified with expression of the reporte ...200515941597
pharmacology and pharmacokinetics of the antiviral agent beta-d-2',3'-dideoxy-3'-oxa-5-fluorocytidine in cells and rhesus monkeys.beta-d-2',3'-dideoxy-3'-oxa-5-fluorocytidine (d-fdoc) is an effective inhibitor of human immunodeficiency virus 1 (hiv-1) and hiv-2, simian immunodeficiency virus, and hepatitis b virus (hbv) in vitro. the purpose of this study was to evaluate the intracellular metabolism of d-fdoc in human hepatoma (hepg2), human t-cell lymphoma (cem), and primary human peripheral blood mononuclear (pbm) cells by using tritiated compound. by 24 h, the levels of d-fdoc-triphosphate (d-fdoc-tp) were 2.8 +/- 0.4, ...200515980324
functional analysis of vif protein shows less restriction of human immunodeficiency virus type 2 by apobec3g.viral infectivity factor (vif) is one of the human immunodeficiency virus (hiv) accessory proteins and is conserved in the primate lentivirus group. this protein is essential for viral replication in vivo and for productive infection of nonpermissive cells, such as peripheral blood mononuclear cells (pbmc). vif counteracts an antiretroviral cellular factor in nonpermissive cells named cem15/apobec3g. although hiv type 1 (hiv-1) vif protein (vif1) can be functionally replaced by hiv-2 vif protein ...200515613310
hiv-2 infection and chemokine receptors usage - clues to reduced virulence of hiv-2.human immunodeficiency virus type 1 (hiv-1) and type 2 (hiv-2) are the causative agents of acquired immunodeficiency syndrome (aids). without therapeutic intervention, hiv-1 or hiv-2 infections in humans are characterized by a gradual and irreversible immunologic failure that ultimately leads to the onset of a severe immunodeficiency that constitutes the hallmark of aids. in the last two decades aids has evolved into a global epidemic affecting millions of persons worldwide. although sharing sev ...200515638719
antigen-specific beta-chemokine production and cd8 t-cell noncytotoxic antiviral activity in hiv-2-infected individuals.human immunodeficiency virus-2 (hiv-2) is less pathogenic than hiv-1, and the disease progression in hiv-2-infected individuals seems to be similar to that seen in hiv-1-infected long-term nonprogressors. cell-mediated immune responses and the production of noncytotoxic cd8+ t-cell antiviral factors (caf) and beta-chemokines have been correlated to protection against hiv-1 and associated with asymptomatic infection and slower disease progression. we investigated the antigen-induced beta-chemokin ...200515644124
the replicative fitness of primary human immunodeficiency virus type 1 (hiv-1) group m, hiv-1 group o, and hiv-2 isolates.the main (m) group of human immunodeficiency virus type 1 (hiv-1) is responsible for the global aids epidemic while hiv-1 group o (outlier) and hiv type 2 are endemic only in west and central africa. the failure of hiv-2 and especially hiv-1 group o to spread following the initial zoonotic jumps is not well understood. this study was designed to examine the relative replicative capacities between these human lentiviruses. a pairwise competition experiment was performed with peripheral blood mono ...200515994792
an envelope-determined, ph-independent endocytic route of viral entry determines the susceptibility of human immunodeficiency virus type 1 (hiv-1) and hiv-2 to lv2 restriction.we identified a postentry restriction, termed lv2, which determines the cellular tropism of two related human immunodeficiency virus type 2 (hiv-2) isolates and is dependent on the sequence of the capsid (ca) and envelope (env) proteins. to explain the reliance on both ca and env, we proposed that restrictive envs deliver susceptible capsids to a compartment where lv2 is active whereas nonrestrictive envs deliver capsids into a compartment where lv2 is either absent or less active. to test this ...200516014904
ccr5, gpr15, and cxcr6 are major coreceptors of human immunodeficiency virus type 2 variants isolated from individuals with and without plasma viremia.human immunodeficiency virus type 2 (hiv-2) is generally considered capable of using a broad range of coreceptors. since hiv-2 variants from individuals with nonprogressive infection were not studied previously, the possibility that broad coreceptor usage is a property of variants associated with progressive infection could not be excluded. to test this, we determined the coreceptor usage of 43 hiv-2 variants isolated from six long-term-infected individuals with undetectable plasma viremia. usin ...200515650194
primary sooty mangabey simian immunodeficiency virus and human immunodeficiency virus type 2 nef alleles modulate cell surface expression of various human receptors and enhance viral infectivity and replication.the nef gene of the pathogenic simian immunodeficiency virus (siv) mac239 clone has been well characterized. little is known, however, about the function of nef alleles derived from naturally sivsm-infected sooty mangabeys (cercocebus atys) and from human immunodeficiency virus type 2 (hiv-2)-infected individuals. addressing this, we demonstrate that, similarly to the sivmac239 nef, primary sivsm and hiv-2 nef alleles down-modulate cell surface expression of human cd4, cd28, cd3, and class i or ...200516051847
short communication: hiv type 2 dynamics.to gain a better understanding of why hiv-2 is less virulent than hiv-1 the viral dynamics of hiv-2 were studied in two swedish hiv-2-infected patients after starting antiretroviral therapy. linear regression analysis of log virus levels in plasma showed that virus decline during the first 2 weeks of therapy followed an exponential decay with half-lives of 2.2 and 2.0 days, respectively. these half-life measurements reflect the decline in the number of cells actively producing the virus, but may ...200516060831
human immunodeficiency virus (hiv)-2-specific t lymphocyte proliferative responses in hiv-2-infected and in hiv-2-exposed but uninfected individuals in guinea-bissau.human immunodeficiency virus (hiv)-2-specific t lymphocyte proliferative responses were determined in cultures of peripheral blood mononuclear cells from hiv-2-exposed uninfected individuals, hiv-2-infected individuals and hiv-negative controls in guinea-bissau. increased hiv-2-specific t lymphocyte proliferative responses were detected in both groups compared to hiv-negative controls (healthy hiv-uninfected individuals without known exposure to an hiv-infected person); five out of 29 of the hiv ...200515730394
quantification of proviral dna load of human immunodeficiency virus type 2 subtypes a and b using real-time pcr.hiv-2 infection is confined mostly to west africa. seven hiv-2 subtypes have so far been described; only hiv-2 subtypes a and b are prevalent, the others being considered self-limiting infections at the epidemiological level. the main limitation for the hiv-2 dna proviral quantification is the lack of hiv-2 dna standard. we designed and tested a new hiv-2 primer couple that amplifies both the hiv-2 rod strain and hiv-1 lav/bru strain. these hiv-2 primers were used to quantified an hiv-2 standard ...200516061978
functional domains within the human immunodeficiency virus type 2 envelope protein required to enhance virus production.primate lentiviruses code for a protein that stimulates virus production. in human immunodeficiency virus type 1 (hiv-1), the activity is provided by the accessory protein, vpu, while in hiv-2 and simian immunodeficiency virus it is a property of the envelope (env) glycoprotein. using a group of diverse retroviruses and cell types, we have confirmed the functional equivalence of the two proteins. however, despite these similarities, the two proteins have markedly different functional domains. wh ...200515731257
performance of a rapid immunochromatographic screening test for detection of antibodies to human immunodeficiency virus type 1 (hiv-1) and hiv-2: experience at a tertiary care hospital in south india.the performance characteristics of a rapid immunochromatographic-screening test, sd bioline hiv-1/2 3.0 (standard diagnostics inc., kyonggi-do, south korea) on 23,754 sera and 30 plasma samples are reported. the sensitivity and specificity for the assay on serum samples are 100% and 99.4%, respectively. the assay detected antibodies in individuals infected with human immunodeficiency virus type 1 (hiv-1) genotypes a and c and hiv-2. this straightforward assay is a reliable diagnostic tool for sc ...200516081975
improved sensitivity of human immunodeficiency virus type 2 subtype b plasma viral load assay.we developed a new assay for human immunodeficiency virus type 2 plasma rna quantification based on a previous format. the new version performed significantly better than the original regarding the detection of subtype b, allowing the detection of 14 out of 36 plasma rnas in the subtype b-infected patients not detected with the original version.200516081987
biology of the hiv nef protein.the accessory nef protein is expressed by all primate lentiviruses--hiv-1,hiv-2 and simian immune deficiency virus (siv). its expression in the early stages of the viral life cycle ensures two basic attributes of hiv infection. these are t-cell activation and the establishment of a persistent state of infection. nef has a positive effect on viral infection and replication by promoting the survival of infected cells. its role in hiv persistence is based largely on the ability of nef to downmodula ...200515817946
attenuation of hiv-1 infection by other microbial agents.although potentiation of human immunodeficiency virus (hiv) type 1 (hiv-1) infection has been known to occur in coinfection with a variety of pathogens and types of vaccination, there are emerging data on specific infectious agents that may attenuate hiv-1 infection. new literature suggests that certain pathogens are capable of inhibiting hiv-1 replication. these include gb virus c, measles virus, orientia tsutsugamushi, and human t lymphotropic virus types 1 and 2. in addition, there are confli ...200516107952
[diagnostic tests: human immunodeficiency virus type 1, type 2 (hiv-1, hiv 2)]. 200516111295
human african trypanosomiasis and human immunodeficiency virus co-infection in western kenya.to determine possible interaction between infections of trypanosoma brucei rhodesiense sleeping sickness and hiv/aids in western kenya.200516122107
infection with a molecularly cloned sivsm virus elicits high titer homologous neutralizing antibodies with heterologous neutralizing activity.we have evaluated the homologous and heterologous neutralizing antibody response in a cohort of six macaca nemestrina infected with the cloned virus sivsm62d that showed different levels of envelope diversification. two progressor macaques developed aids by 1.5 years post-inoculation and four non-progressors were asymptomatic for 3 years of follow-up. all macaques developed high titers of neutralizing antibodies against homologous sivsm viruses and intermediate titers against sivsmb670. heterolo ...200516128920
differential restriction of human immunodeficiency virus type 2 and simian immunodeficiency virus sivmac by trim5alpha alleles.primate lentiviruses have narrow host ranges, due in part to their sensitivities to mammalian intracellular antiviral factors such as apobec3g and trim5alpha. despite the protection provided by this innate immune system, retroviruses are able to transfer between species where they can cause disease. this is true for sooty mangabey simian immunodeficiency virus, which has transferred to humans as hiv-2 and to rhesus macaques as sivmac, where it causes aids. here we examine the sensitivities of th ...200516140735
cd8+ t cell responses to human immunodeficiency viruses type 2 (hiv-2) and type 1 (hiv-1) gag proteins are distinguishable by magnitude and breadth but not cellular phenotype.the mechanisms underlying the relatively slow progression of human immunodeficiency virus type 2 (hiv-2) compared with hiv-1 infection are undefined and could be a result of more effective immune responses. we used hiv-2 and hiv-1 ifn-gamma enzyme-linked immunospot assays to evaluate cd8(+) t cell responses in antiretroviral-naive hiv-2- ('hiv-2(+)') and hiv-1-infected ('hiv-1(+)') individuals. gag-specific responses were detected in the majority of hiv-2(+) and hiv-1(+) subjects. overlapping ga ...200515832290
novel single-round pcr and cloning of full-length envelope genes of hiv-1 may yield new insight into biomolecular antibacterial drug development.nested or semi-nested polymerase chain reaction (pcr) with a 'hot start' is the preferred amplification method for full-length, in-frame envelope genes (gp160) of the human immunodeficiency virus type 1 (hiv-1). this generally follows an extensive screening process. this paper describes an effective single-round pcr method and cloning process for hiv-1 gp160 from clinical samples, and cell and tissue cultures developed during the early stages of construction of a molecular hiv-1 vaccine. the amp ...200515847926
simian immunodeficiency virus infection in free-ranging sooty mangabeys (cercocebus atys atys) from the taï forest, côte d'ivoire: implications for the origin of epidemic human immunodeficiency virus type 2.simian immunodeficiency virus of sooty mangabeys (sivsmm) is recognized as the progenitor of human immunodeficiency virus type 2 (hiv-2) and has been transmitted to humans on multiple occasions, yet the epidemiology and genetic diversity of sivsmm infection in wild-living populations remain largely unknown. here, we report the first molecular epidemiological survey of sivsmm in a community of approximately 120 free-ranging sooty mangabeys in the taï forest, côte d'ivoire. fecal samples (n = 39) ...200516160179
genomic diversity of human immunodeficiency viruses.globally circulating strains of human immunodeficiency virus type one (hiv-1) exhibit an extraordinary degree of genetic diversity. sequences derived from hiv-1 strains have historically been classified on the basis of their phylogenetic relationships. the viruses have been classified into groups, subtypes or clades and circulating recombinant forms (crfs). groups were originally named m for main, o for outlier and n for non-m-non-o. the identification of subtypes and crfs provides a means of tr ...200527407775
evidence for negative selective pressure in hiv-2 evolution in vivo.hiv-2 sequence divergence and evolution in vivo has not been well characterized so far. to investigate the extent of hiv-2 genetic diversity and better understand how hiv-2 evolves in vivo, env c2-c3 nucleotide sequences were obtained from the plasma and pbmcs virus populations of four hiv-2 patients with different infection periods. phylogenetic analysis showed that three patients were infected with subtype a hiv-2 and the remaining patient was infected with a divergent hiv-2 that could not be ...200415737915
characterization of virus infectivity and cell-free capsid assembly of sivmnecl8.we have previously described a cell-free system that reconstitutes immature capsid assembly of gag polypeptides from viruses belonging to three major primate lentiviral lineages, including hiv-1, hiv-2 and sivagm. studies described here examine a member of the sivmac/mne lineage, sivmnecl8, using assays for virus production and infectivity as well as cellular events in capsid formation. we report that sivmnecl8, a molecular clone with properties typical of transmitted viral variants, is less inf ...200415525327
phylogenetic demonstration of two cases of perinatal human immunodeficiency virus type 2 infection diagnosed in adulthood.hiv-2 infection was diagnosed in two patients 15 and 24 years of age and, thereafter, in their mothers. epidemiological data suggested that vertical transmission was the most probable mode of infection in both patients (mota-miranda a, et al.: aids 2001;15:2460-2461). phylogenetic analysis of env c2-c3 sequences from the patients and their mothers was used in an attempt to confirm or exclude the events of perinatal hiv-2 transmission. sequences from each putative transmission pair formed monophy ...200415650432
human immunodeficiency virus type 2 gag interacts specifically with prp4, a serine-threonine kinase, and inhibits phosphorylation of splicing factor sf2.using a yeast two-hybrid screen of a t-cell cdna library to identify cellular proteins that bind to the human immunodeficiency virus type 2 (hiv-2) gag polyprotein, we identified prp4, a serine-threonine protein kinase. specific interaction of prp4 and hiv-2 gag was confirmed in in vitro and in vivo assays. the interacting region of hiv-2 gag is located in the conserved matrix and capsid domains, while both the rs (arginine-serine-rich) domain and the ks (kinase) domain of prp4 are able to bind ...200415452250
comparison of human immunodeficiency virus (hiv)-specific t-cell responses in hiv-1- and hiv-2-infected individuals in senegal.human immunodeficiency virus type 2 (hiv-2) infection is typically less virulent than hiv-1 infection, which may permit the host to mount more effective, sustained t-cell immunity. we investigated antiviral gamma interferon-secreting t-cell responses by an ex vivo elispot assay in 68 hiv-1- and 55 hiv-2-infected senegalese patients to determine if differences relate to more efficient hiv-2 control. homologous hiv-specific t cells were detected in similar frequencies (79% versus 76%, p = 0.7) and ...200415564501
enigmas and paradoxes: the genetic diversity and prevalence of the primate lentiviruses.in a comparatively few years a previously unknown virus has spread from its animal host to infect more than 40 million people by the end of 2003, causing an estimated 3 million deaths in that year (world health organization figures). the size of this human immunodeficiency virus (hiv) epidemic and its associated health, social and economic problems make it imperative that we understand how its two types, hiv-1 and hiv-2, have evolved from their simian relatives, the primate lentiviruses (plvs). ...200415078176
the natural history of hiv-1 and hiv-2 infections in adults in africa: a literature review.about 30 million people in africa are estimated to be living with human immunodeficiency virus/acquired immune deficiency syndrome (hiv/aids), yet data about the natural history of infection on the continent are sparse. we reviewed the literature on the natural history of hiv-1 and hiv-2 infections among african adults. only one study, conducted in rural uganda, has reported on survival from the time of hiv-1 seroconversion: the median was 9.8 years, which is similar to that reported in develope ...200415356940
field evaluation of a rapid human immunodeficiency virus (hiv) serial serologic testing algorithm for diagnosis and differentiation of hiv type 1 (hiv-1), hiv-2, and dual hiv-1-hiv-2 infections in west african pregnant women.we evaluated a two-rapid-test serial algorithm using the determine and genie ii rapid assays, performed on-site in four peripheral laboratories during the french agence nationale de recherches sur le sida (anrs) 1201/1202 ditrame plus cohort developed for prevention of mother-to-child transmission of human immunodeficiency virus (hiv) infection in côte d'ivoire. a total of 1,039 specimens were retested by two commercial enzyme-linked immunosorbent assays (elisas). the following specimens were te ...200415365003
t-cell activation leads to poor activation of the hiv-1 clade e long terminal repeat and weak association of nuclear factor-kappab and nfat with its enhancer region.the enhancer region in the human immunodeficiency virus type 1 (hiv-1) 5'-long terminal repeat (ltr) is very important for viral transcription. this promoter sequence binds both nuclear factor-kappab and nfat, two important modulators of hiv-1 gene expression. previous studies have indicated that the enhancer regions of the different hiv-1 clade ltrs differ in their number of nf-kappab-binding sites. in this study, we have compared the activation potential of the different hiv-1 clade and hiv-2 ...200415466412
aids as a zoonosis? confusion over the origin of the virus and the origin of the epidemics.based on findings demonstrating the simian ancestry of hiv, aids has been reported to be a zoonosis. however, this theory has never been proved and must seriously be questioned. several arguments show that hiv-aids is not a zoonosis. (i) if aids were a zoonosis, there must be evidence of aids being directly acquired from an animal species, as is rabies, a disease that is directly acquired from animals. (ii) despite long-term and frequent human exposure to siv-infected monkeys in africa, only 11 ...200415525322
codon optimization of the tat antigen of human immunodeficiency virus type 1 generates strong immune responses in mice following genetic immunization.dna vaccines have been successful in eliciting potent immune responses in mice. their efficiency, however, is restricted in larger animals. one reason for the limited performance of the dna vaccines is the lack of molecular strategies to enhance immune responses. additionally, genes directly cloned from pathogenic organisms may not be efficiently translated in a heterologous host expression system as a consequence of codon bias. to evaluate the influence of codon optimization on the immune respo ...200415308713
chemokine receptor ccr5: insights into structure, function, and regulation.cc chemokine receptor 5 (ccr5) is a seven-transmembrane, g protein-coupled receptor (gpcr) which regulates trafficking and effector functions of memory/effector t-lymphocytes, macrophages, and immature dendritic cells. it also serves as the main coreceptor for the entry of r5 strains of human immunodeficiency virus (hiv-1, hiv-2). chemokine binding to ccr5 leads to cellular activation through pertussis toxin-sensitive heterotrimeric g proteins as well as g protein-independent signalling pathways ...200415337520
prevalence and incidence of hiv, hepatitis b virus, and hepatitis c virus infections among males in rhode island prisons.we evaluated prevalence and intraprison incidence of hiv, hepatitis b virus, and hepatitis c virus infections among male prison inmates.200415226146
current status of the non-nucleoside reverse transcriptase inhibitors of human immunodeficiency virus type 1.almost fifteen years ago, the first non-nucleoside reverse transcriptase (rt) inhibitor (nnrti) lead compounds have been discovered. nowadays, three nnrtis are approved for treatment of hiv-1-infected individuals and several others are subject of (advanced) clinical trials. although the nnrtis target hiv-1 rt, they are clearly different from the nucleoside rt inhibitors (nrtis). they are highly selective for hiv-1 and do not inhibit hiv-2 or any other (retro)virus. they target hiv-1 rt by a dire ...200415134549
chronic hiv-2 infection protects against total cd4+ cell depletion and rapid disease progression induced by shiv89.6p challenge.to better understand hiv-1 sexual transmission risk, we have studied the susceptibility of hiv-2-exposed, uninfected (eu) female pig-tailed macaques to intravaginal (ivag) re-challenge with the homologous hiv-2 strain, followed by heterologous shiv89.6p.200415166528
a single amino acid substitution in human apobec3g antiretroviral enzyme confers resistance to hiv-1 virion infectivity factor-induced depletion.hiv-1 and other retroviruses occasionally undergo hypermutation, characterized by a high rate of g-to-a substitution. recently, the human apolipoprotein b mrna-editing, enzyme-catalytic, polypeptide-like 3g (apobec3g), first identified as cem15, was shown to be packaged into retroviral virions and to deaminate deoxycytidine to deoxyuridine in newly synthesized viral minus-strand dna, thereby inducing g-to-a hypermutation. this innate mechanism of resistance to retroviral infection is counteracte ...200415054139
identification of a highly divergent hiv type 2 and proposal for a change in hiv type 2 classification.we report the complete genome sequence of a highly divergent strain of human immunodeficiency virus type 2 (hiv-2), 96fr12034, identified in france from a patient of west african origin. this lineage, h, represents only the third definitive instance of a monkey-to-human transfer of sivsm that has given rise to pathogenic hiv-2. as the different "subtypes" of hiv-2 are analogous to the different groups of hiv-1 we propose that hiv-2 subtypes henceforth by renamed groups in agreement with the hiv ...200415242544
human retroviruses in leukaemia and aids: reflections on their discovery, biology and epidemiology.the study of retroviruses has had a profound impact by unveiling an unusual form of viral replication: the multiplication of rna viruses via a proviral dna, for which jan svoboda provided the experimental model over forty years ago. in 1970 temin, mizutani and baltimore discovered that this group of viruses contains a unique enzyme catalysing the synthesis of a dna copy of the viral rna: reverse transcriptase (rt). the discovery of rt has itself had an enormous impact on molecular biology in gen ...200415682876
elevated expression of gm3 in receptor-bearing targets confers resistance to human immunodeficiency virus type 1 fusion.gm3, a major ganglioside of t lymphocytes, promotes human immunodeficiency virus type 1 (hiv-1) entry via interactions with hiv-1 receptors and the viral envelope glycoprotein (env). increased gm3 levels in t lymphocytes and the appearance of anti-gm3 antibodies in aids patients have been reported earlier. in this study, we investigated the effect of gm3 regulation on hiv-1 entry by utilizing a mouse cell line (b16f10), which expresses exceptionally high levels of gm3. strikingly, b16 cells bear ...200415220409
highly active antiretroviral therapy and viral response in hiv type 2 infection.human immunodeficiency virus type 2 (hiv-2), the second human retrovirus known to cause aids, is endemic to west africa but is infrequently found outside this region. we present a case series of 10 hiv-2--infected individuals treated in the united states. physicians applied the principles of highly active antiretroviral therapy (haart), normally used in treating hiv type 1, with modifications considered appropriate for treating hiv-2. cd4+ cell count, hiv-2 virus load, and clinical status were f ...200415227626
a link between sivsm in sooty mangabeys (sm) in wild-living monkeys in sierra leone and sivsm in an american-based sm colony.we have developed a noninvasive method for sivsm virion rna detection in feces of captive sooty mangabeys (sms) (cercocebus atys). employing this method to investigate the natural history of sivsm in endangered sms is useful for understanding the diversity and evolution of sivsm and hiv-2. the fecal samples of 61 wild-living sms and 14 chimpanzees (pan troglodytes verus) were studied. samples were collected in rural sierra leone in 1993. one sm sample tested positive by reverse transcriptase-pcr ...200415650427
antiretroviral drug resistance in non-subtype b hiv-1, hiv-2 and siv.patients infected with hiv-1 of subtype other than b ('non-subtype b') or with hiv-2 are being treated with antiretroviral drugs in increasing numbers. in addition, healthcare providers and laboratory workers working with clinical specimens or animals infected with hiv, siv or shiv are at risk of being exposed to the virus and might require post-exposure prophylactic treatment. thus, it is important to understand the inherent antiviral susceptibility of non-subtype b hiv-1, hiv-2 and siv to curr ...200415040531
the phenylmethylthiazolylthiourea nonnucleoside reverse transcriptase (rt) inhibitor msk-076 selects for a resistance mutation in the active site of human immunodeficiency virus type 2 rt.the phenylmethylthiazolylthiourea (pett) derivative msk-076 shows, besides high potency against human immunodeficiency virus type 1 (hiv-1), marked activity against hiv-2 (50% effective concentration, 0.63 microm) in cell culture. time-of-addition experiments pointed to hiv-2 reverse transcriptase (rt) as the target of action of msk-076. recombinant hiv-2 rt was inhibited by msk-076 at 23 microm. as was also found for hiv-1 rt, msk-076 inhibited hiv-2 rt in a noncompetitive manner with respect t ...200415220416
analysis of 15 novel full-length bk virus sequences from three individuals: evidence of a high intra-strain genetic diversity.to determine the variability of bk virus (bkv) in vivo, the sequences of nine full-length molecular clones from the striated muscle and heart dna of a patient with bkv-associated capillary leak syndrome (bkvcap), as well as three clones each from the urine of one human immunodeficiency virus type 2-positive (bkvhi) and one healthy control subject (bkvhc), were analysed. the regulatory region of all clones corresponded to the archetypal regulatory region usually found in urine isolates. analysis ...200415302959
functional solubilization of aggregation-prone hiv envelope proteins by covalent fusion with chaperone modules.the envelope proteins of human immunodeficiency virus (hiv) and human t-cell lymphotrophic virus (htlv) mediate cell attachment and membrane fusion. for hiv-1, the precursor protein gp160 is cleaved proteolytically into two fragments, the surface-associated receptor binding subunit gp120 and the membrane spanning subunit gp41, which is involved in membrane fusion during virus entry. soluble and immunoreactive variants of gp41 are essential for the reliable diagnosis of hiv-1 infections. hitherto ...200415644217
[guillain-barré syndrome in hiv-infected patients at bobo-dioulasso hospital (burkina faso)].neurological manifestations of human immunodeficiency virus (hiv) infection are frequent and several associated peripheral neuropathies have been recognized. among them, guillain-barré syndrome (gbs) may occur either early or during the course of the illness. we present a prospective study of 32 consecutive cases of gbs managed over a 5-year period at bobo-dioulasso hospital where hiv prevalence reaches 20.1p.cent. male gender predominated (24/32). gbs occurred during the dry season for 65.7p.ce ...200415269674
phenotypic susceptibility to nonnucleoside inhibitors of virion-associated reverse transcriptase from different hiv types and groups.to evaluate a phenotype assay based on plasma reverse transcriptase (rt) to assess hiv susceptibility to nonnucleoside rt inhibitors (nnrtis). to compare rt-based phenotype with recombinant virus assay (rva) phenotype- and genotype-based analysis. to assess group o and hiv-2 susceptibility to nnrtis in correlation with genotype polymorphisms.200415577405
rapid discrimination between human immunodeficiency virus type 2 groups a and b by real-time pcr.we studied the feasibility of genotyping human immunodeficiency virus (hiv) type 2 groups a and b by real-time pcr. two group-specific pcrs were developed. real-time genotyping of 22 samples of genotype a, 10 samples of genotype b, and the isolate of new group h were compared to genotyping by sequencing and phylogeny. the group-specific pcrs specifically identified 84.3% of group a or b samples; isolate h was not detected. this method allowed rapid and specific discrimination between hiv-2 group ...200415583327
differential regulation of human immunodeficiency virus type 2 and simian immunodeficiency virus promoter activity.promoter activity of the hiv-1 long terminal repeat (ltr) is largely dependent on intact nf-kb and spi binding sites in the u3 region. in contrast, upstream ltr sequences allow efficient simian immunodeficiency virus (sivmac) transcription in the absence of the core enhancer promoter region. in the present study, we investigated whether the regulation of hiv-2 rod ltr activity is more reminiscent of hiv-1 having the same host or of sivmac239 belonging to the same phylogenetic group. viral promot ...200415207635
the rationale for pathogen-inactivation treatment of blood components.blood transfusion provides an ideal portal of entry for microorganisms. although current residual risks of microbial infection by transfusion are extremely low in the developed world, the requirements for even safer blood are paradoxically increasing. such requirements are partly a legacy of the tragic transmissions of human immunodeficiency virus (hiv) by blood early in the acquired immunodeficiency syndrome pandemic and are legally expressed in consumer protection laws imposing strict product ...200415615254
hiv-2-infected individuals with undetectable plasma viremia carry replication-competent virus in peripheral blood lymphocytes.using an optimized hiv co-culture protocol it was possible to isolate infectious hiv-2 variants from 6 hiv-2-infected individuals who had undetectable plasma viremia and maintained high cd4 t-cell numbers for prolonged periods. this shows for the first time that hiv-2-infected individuals with no demonstrable in vivo virus production carry replication-competent virus in peripheral blood mononuclear cells (pbmcs). the frequency of pbmcs with infectious virus was low, ranging from 0.01-0.9 infecti ...200415213560
no differences in cellular immune responses between asymptomatic hiv type 1- and type 2-infected gambian patients.fewer people infected with human immunodeficiency virus (hiv) type 2 progress to acquired immunodeficiency syndrome, compared with those infected with hiv-1. to understand the immune mechanisms leading to slow progression in hiv-2 infection, cell-mediated immune responses were compared between the 2 infections in asymptomatic subjects with a cd4 cell count > or =20%. interferon- gamma release from t lymphocytes and the cytotoxicity of cd8+ t lymphocytes were measured by elispot and 51cr release ...200414745708
conservation of a stepwise, energy-sensitive pathway involving hp68 for assembly of primate lentivirus capsids in cells.previously we have described a stepwise, energy-dependent pathway for human immunodeficiency virus type 1 (hiv-1) capsid assembly in a cell-free system. in this pathway, gag polypeptides utilize the cellular factor hp68 and assemble into immature capsids by way of assembly intermediates that have defined biochemical characteristics. here we address whether this pathway is universally conserved among primate lentiviruses and can be observed in mammalian cells. we demonstrate that hiv-2 gag associ ...200414747530
[hiv-2 and htlv-i/ii infections in spain].up to december 2002, a total of 56, 566 and 109 cases of human t-lymphotropic virus type 1 (htlv-i), htlv-ii and human immunodeficiency virus type 2 (hiv-2) infection, respectively, were identified in spain. most htlv-i- and hiv-2-infected subjects were immigrants from endemic areas or spaniards who had traveled to, or had sexual contacts with natives from, these areas. in contrast, htlv-ii infection was mainly limited to spanish intravenous drug users (idu) who were frequently coinfected with h ...200414987538
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