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J Goudsmit

Publications and source records attributed to J Goudsmit.

At least 109 records · Page 6Linked to original sources
PubMed1998

CCR5 coreceptor usage of non-syncytium-inducing primary HIV-1 is independent of phylogenetically distinct global HIV-1 isolates: delineation of consensus motif in the V3 domain that predicts CCR-5 usage.

The cellular tropism of human immunodeficiency virus type 1 (HIV-1) is dependent on utilization of specific chemokine co-receptor: macrophage-tropic/non-syncytium-inducing (NSI) viruses use CCR5, whereas T-cell tropic/syncytium-inducing (SI) viruses preferentially use CXCR4. We have analyzed co-receptor usage of 24 phylogenetically distinct primary HIV-1 isolates representing group M (clades A-F) and group O with known SI and NSI phenotype, using lymphocytes from donor with nonfunctional CCR5 (CCR5-/-; homozygous 32-bp deletion). While all SI isolates infected CCR5-/- lymphocytes (and hence do not require CCR5 for viral entry), all NSI isolates, regardless of clade, did not infect CCR5-/- lymphocytes. Thus, CCR5 expression is required for infection with NSI isolates and the CCR5 usage is independent of viral genotype. To localize the viral determinant involved in CCR5 binding, the V3 sequences across the clades were aligned based on the CCR5 usage. There were conserved uncharged residues at position 11 of V3 (mostly serine/glycine) and negatively charged residues at residue 25 (mostly glutamic/aspartic acid) among all isolates that used CCR5, whereas substitution with arginine or glutamine at these two positions led to usage of a co-receptor other than CCR5. This analysis led us to identify a consensus motif S/GXXXGPGXXXXXXXE/D within the V3 loop that predicts CCR5 co-receptor usage. Most isolates, with exception of one isolate, containing the conserved motif and predicted to utilize CCR5 indeed had an absolute requirement of CCR5 expression for infectibility. Site-directed mutagenesis in the infectious molecular clone further confirmed these results. Taken together, these data provide evidence that sequences within the V3 loop provide important residues that might be directly or indirectly involved in binding to a CCR5 co-receptor.

Amino Acid Sequence↗
PubMed1998

Role of CCR2 genotype in the clinical course of syncytium-inducing (SI) or non-SI human immunodeficiency virus type 1 infection and in the time to conversion to SI virus variants.

The effect of a valine to isoleucine switch in the CCR2 first transmembrane domain (CCR2 64I) on the clinical course of human immunodeficiency virus type 1 (HIV-1) infection was analyzed in relation to the presence or absence of syncytium-inducing (SI) HIV-1 variants. Compared with persons with a wild-type genotype for CCR2 and CCR5, subjects with a CCR2-64I/+ or 64I/64I (but CCR5 wild-type homozygous genotype) had significantly delayed disease progression (relative hazard, 0.66; 95% confidence interval, 0.44-0.99) with a 1. 5-fold slower CD4 T lymphocyte decline and a 1.2-fold lower RNA virus load. The delay in disease progression was more pronounced when only non-SI (NSI) HIV-1 variants were present and was not observed after conversion to SI HIV-1 in CCR2-64I/+ persons. In CCR2-64I/+ subjects, a higher conversion rate to and a higher prevalence of SI HIV-1 was observed. These findings suggest that the mechanism of action of the CCR2 polymorphism is mediated via CCR5-restricted NSI HIV-1 variants.

Cells, Cultured↗
PubMed1998

Human immunodeficiency virus type 1 in faeces and serum: evidence against independently evolving subpopulations.

It is not known whether independent tissue-specific evolution accounts for the differences between human immunodeficiency virus type 1 (HIV-1) subpopulations in intestinal tissue and blood. To study this, sequential serum samples from three persons were analysed for the presence of HIV-1 V3 genotypes which were detected exclusively in faeces at a specific time-point. For two persons the faeces genotype was found in serum samples collected before the time of faeces collection: 7 months for one person and 32 months for the other person. In the third person, serum collected 1 month after faeces collection contained the faeces genotype in abundance. These data indicate that a difference between intestinal tissue and blood HIV-1 subpopulations is not the result of complete compartmentalization and independent HIV-1 evolution in intestinal tissue, but that it reflects an unequal distribution of HIV-1 in different tissues.

Amino Acid Sequence↗
PubMed1998

Characteristics of primary infection of a European human immunodeficiency virus type 1 clade B isolate in chimpanzees.

The aim of the study was to select, from a panel of candidate European human immunodeficiency virus type 1 (HIV-1) clade B primary virus isolates, one isolate based on replication properties in chimpanzee peripheral blood mononuclear cells (PBMC). Secondly, to evaluate the in vivo kinetics of primary infection of the selected isolate at two different doses in two mature, outbred chimpanzees (Pan troglodytes). Four different low passage, human PBMC-cultured 'primary' HIV-1 isolates with European clade B consensus sequence were compared for their ability to replicate in vitro in chimpanzee versus human PBMC. The isolate which yielded the highest titre and most vigorous cytopathic effect in chimpanzee PBMC was evaluated for coreceptor usage and chosen for evaluation in vivo. Only the HIV-1Han2 isolate replicated in chimpanzee PBMC in vitro at detectable levels. This isolate was demonstrated to utilize CCR4, CCR5 and CXCR4 coreceptors and could be inhibited by beta-chemokines. Infection of chimpanzees was demonstrated by viral RNA and DNA PCR analysis, both in plasma as well as in PBMC and lymph node cells as early as 3 weeks after inoculation. Antibodies developed within 6 weeks and continued to increase to a maximum titre of approximately 12800, thereafter remaining in this range over the follow-up period of 2 years. Compared to cell line-adapted HIV-1 isolates there were slight but no dramatic differences in the kinetics of infection of chimpanzees with this particular primary isolate.

Animals↗
PubMed1998

Genetic differences between human immunodeficiency virus type 1 subpopulations in faeces and serum.

To study human immunodeficiency virus type 1 (HIV-1) compartmentalization between intestine and blood, paired faecal and serum samples were collected from 204 HIV-1-infected persons. Direct sequencing of the gp120 V3 region obtained from 33 persons showed that faecal and serum sequences could be nearly homologous (0.3% different) or very dissimilar (11.3% different). Individual clones were obtained and sequenced from the faecal and serum samples of 13 persons. In 6 persons the HIV-1 subpopulations in faeces and serum were similar, whereas in 7 persons, distribution of V3 genotypes showed a marked difference. Genetic characterization of the HIV-1 subpopulations showed less heterogeneity in faecal subpopulations than in serum subpopulations in 5 of the 7 subjects. Furthermore, faecal and serum subpopulations differed predominantly by nonsynonymous nucleotide substitutions (in 6 of 7 persons). Comparison of the HIV-1 subpopulations in faeces and serum of these 7 persons, using resampling techniques, revealed a significant difference between faecal and serum subpopulations at an N-linked glycosylation site, C-terminal of the V3 loop (amino acids 331-333). Sequences from faecal subpopulations of all 7 persons contained a glycosylation site at amino acid position 331-333. Four of these 7 harboured serum variants lacking a glycosylation site at this position. The faecal subpopulations in these 4 persons showed limited nonsynonymous substitutions compared to synonymous substitutions, indicating that purifying selection is operational on these subpopulations.

Acquired Immunodeficiency Syndrome↗
PubMed1998

Hepatitis C virus serotype-specific core and NS4 antibodies in injecting drug users participating in the Amsterdam cohort studies.

In the present study, the RIBA HCV serotyping SIA was evaluated with a cohort of injecting drug users. Serotyping may be a rapid and cost-effective method of determining genotypes in cohort studies. In this study, hepatitis C virus (HCV) antibody-positive sera from a cohort of 331 chronically infected injecting drug users, of which 167 were coinfected with human immunodeficiency virus (HIV), were serotyped by the RIBA HCV Serotyping SIA. Among the 331 specimens, serotype-specific antibodies were detected in 250 (sensitivity, 75. 5%), in which serotype 1 was predominant (57.2%), followed by serotype 3 (26.8%). Among the 331 specimens, 164 were HIV negative, and serotype-specific antibodies were detected in 151 (sensitivity, 92.1%), in which serotype 1 was predominant (59.6%), followed by serotype 3 (33.8%). For a subset of 58 samples taken from 19 chronically infected HCV seroconverters with a mean follow-up of 5 years, serotypes were compared with genotypes, which were determined by a line probe assay (HCV LiPa) and by direct sequencing of the products obtained by nested PCR of the 5' untranslated region. Among the 58 samples with known genotypes, serotype-specific antibodies were detected in 38 (total sensitivity, 65.5%), with a specificity of 78.9%. Thirty of these serotypeable samples revealed a serotype that corresponded to the genotype in the 58 samples (total positive predictive value, 51.7%). Of the 58 samples, 23 were coinfected with HIV, and when these were excluded, the total sensitivity increased to 76.5%, with a total specificity of 80.8% and a total positive predictive value of 61.8%. The serotyping assay showed a high total sensitivity (96.3%) for samples positive by HCV RIBA, version 3.0, with four bands. We conclude that the sensitivity of the RIBA HCV serotyping SIA is limited by the immunocompetence of the HCV-infected host. In general, samples from HIV-negative individuals containing genotype 1a had higher sensitivity, specificity, and concordance in the serotyping assay compared with genotyping, whereas samples containing genotype 3a were found to be more cross-reactive and untypeable. Therefore, the prevalence of genotypes other than genotype 1 could be underestimated if they are determined by serotyping, and improvements in specificity are recommended.

Cohort Studies↗
PubMed1998

Different hepatitis C virus (HCV) RNA load profiles following seroconversion among injecting drug users without correlation with HCV genotype and serum alanine aminotransferase levels.

Hepatitis C virus (HCV) infection often persists in association with chronic hepatitis. Different factors have been proposed to determine the clinical outcome of HCV infection. The aim of this study was to examine three different factors of HCV infection among injecting drug users. Nineteen untreated HCV seroconverters were tested longitudinally for the presence of HCV RNA by reverse transcriptase (RT) PCR, and results were quantified by the branched-DNA (bDNA) assay. HCV genotypes were determined with the first sample taken after HCV seroconversion. To assess the natural course of infection, serum alanine aminotransferase (ALT) levels were measured at three stages in every individual. The concordance between bDNA and RT-PCR was 98.9%. Three distinct patterns were found, according to the HCV RNA load after seroconversion during a mean follow-up period of 5 years (range, 1 to 8 years). HCV genotype 1a was predominant (52.6%). There was a significant increase in serum ALT levels (mean 55.5 U/liter) in the early phase of HCV infection, compared with basal serum ALT levels before HCV seroconversion and at the end of the follow-up period. Three distinct HCV RNA load profiles were found, without apparent relationship to genotype and serum ALT levels in the first 5 years of HCV infection.

Alanine Transaminase↗
PubMed1998

Infectious cellular load in human immunodeficiency virus type 1 (HIV-1)-infected individuals and susceptibility of peripheral blood mononuclear cells from their exposed partners to non-syncytium-inducing HIV-1 as major determinants for HIV-1 transmission in homosexual couples.

To study risk factors for homosexual transmission of human immunodeficiency virus type 1 (HIV-1), we compared 10 monogamous homosexual couples between whom transmission of HIV-1 had occurred with 10 monogamous homosexual couples between whom HIV-1 transmission had not occurred despite high-risk sexual behavior. In the group of individuals who did not transmit virus, peripheral cellular infectious load was lower and the CD4+ T-cell counts were higher than in the group of transmitters. HIV-1 RNA levels in serum did not differ between transmitters and nontransmitters. Compared with peripheral blood mononuclear cells (PBMC) from normal healthy blood donors, 8 of 10 nonrecipients and only 3 of 8 recipients had PBMC with reduced susceptibility to in vitro infection with non-syncytium-inducing (NSI) HIV-1 variants isolated from either their respective partners or an unrelated individual. No difference in susceptibility was observed for infection with a syncytium-inducing variant. Among the individuals who had PBMC with reduced susceptibility, five nonrecipients and one recipient had PBMC that were equally or even less susceptible to NSI variants than PBMC that had low susceptibility and that were derived from healthy blood donors that were heterozygous for a 32-bp deletion in the CCR5 gene (CCR5 delta32). Three of these individuals (all nonrecipients) had a CCR5 delta32 heterozygous genotype themselves, confirming an association between low susceptibility to NSI variants and CCR5 delta32 heterozygosity. All three recipients with less susceptible PBMC had partners with a high infectious cellular load; inversely, both nonrecipients with normally susceptible PBMC had partners with a very low infectious cellular load. These results suggest that a combination of susceptibility of target cells and inoculum size upon homosexual exposure largely determines whether HIV-1 infection is established.

Adult↗
PubMed1998

Structured-tree topology and adaptive evolution of the simian immunodeficiency virus SIVsm envelope during serial passage in rhesus macaques according to likelihood mapping and quartet puzzling.

Species-specific strains of simian immunodeficiency virus (SIV) are nonpathogenic in African primates. The SIV strain most closely related to human immunodeficiency virus type 2 (HIV-2) is SIVsm, the strain specific to the sooty mangabey (Cercocebus atys). Infection of Asian primates with SIV causes AIDS and allows the study of the adaptive evolution of a lentivirus to replicate efficiently in a new host, providing a useful animal model of HIV infection and AIDS in humans. Serial passage of SIVsm from sooty mangabeys in rhesus macaques drastically shortened the time of disease progression from 1.5 years to 1 month as the retrovirus adapted to these Asian hosts. In the present study we analyzed the quasispecies nature of the SIVsm envelope gene (env) during serial population passage in rhesus macaques. We asked ourselves if phylogenetic evidence could be provided for the structured topology of the SIVsm env tree and subsequently for the adaptive evolution of SIVsm env. Likelihood mapping showed that phylogenetic reconstruction of the passage was possible because a high percentage of the sequence data had a "tree-like" form. Subsequently, quartet puzzling was used and produced a phylogeny with a structure parallel to the known infection history. The adaptation of SIVsm to Asian rhesus macaques appears to be an ordered process in which the env evolves in a tree-like manner, particularly in its constant regions.

Adaptation, Biological↗
PubMed1998

Shortening of the symptom-free period in rhesus macaques is associated with decreasing nonsynonymous variation in the env variable regions of simian immunodeficiency virus SIVsm during passage.

During six blood passages of simian immunodeficiency virus SIVsm in rhesus macaques, the asymptomatic period shortened from 18 months to 1 month. To study SIVsm envelope gene (env) evolution during passage in rhesus macaques, the C1 to CD4 binding regions of multiple clones were sequenced at seroconversion and again at death. The env variation found during adaptation was almost completely confined to the variable regions. Intrasample sequence variation among clones at seroconversion was lower than the variation among clones at death. Intrasample variation among clones from a single time point as well as intersample variation decreased during the passage. In the variable regions, the mean number of intrasample nonsynonymous nucleotide substitutions decreased from the first passage (5.26 x 10(-2) +/- 0.6 x 10(-2) per site) to the fifth passage (2.24 x 10(-2) +/- 0.4 x 10(-2) per site), whereas in the constant regions, the mean number of intrasample nonsynonymous nucleotide substitutions differed less between the first and fifth passages (1. 14 x 10(-2) +/- 0.27 x 10(-2) and 0.80 x 10(-2) +/- 0.24 x 10(-2) per site). Shortening of the asymptomatic period coincided with a rise in the Ks/Ka ratio (ratio between the number of synonymous [Ks] and the number of nonsynonymous [Ka] substitutions) from 1.080 in passage one to 1.428 in passage five and mimicked the difference seen in the intrahost evolution between asymptomatic and fast-progressing individuals infected with human immunodeficiency virus type 1. The distribution of nonsynonymous substitutions was biphasic, with most of the adaptation of env variable regions occurring in the first three passages. This phase, in which the symptom-free period fell to 4 months, was followed by a plateau phase of apparently reduced adaptation. Analysis of codon usage revealed decreased codon redundancy in the variable regions. Overall, the results suggested a biphasic pattern of adaptation and evolution, with extremely rapid selection in the first three passages followed by an equilibrium or stabilization of the variation between env clones at different time points in passages four to six.

Animals↗
PubMed1997

Association between CCR5 genotype and the clinical course of HIV-1 infection.

BACKGROUND: Heterozygosity for a 32-nucleotide deletion in the C-C chemokine receptor 5 gene (CCR5 delta 32) is associated with delayed disease progression in persons infected with HIV-1. OBJECTIVE: To compare the predictive value of CCR5 genotype with that of established markers in the clinical course of HIV-1 infection. DESIGN: Retrospective longitudinal study and nested case-control study. The latter included only long-term survivors, who were individually matched with progressors. SETTING: Amsterdam, the Netherlands. PARTICIPANTS: 364 homosexual men with HIV-1 infection. MEASUREMENTS: Polymerase chain reaction was used for CCR5 genotyping. Univariate and multivariate Cox proportional hazard analyses were done for disease progression with CCR5 genotype, CD4+ T-lymphocyte counts, T-lymphocyte function, HIV-1 biological phenotype (syncytium-inducing or non-syncytium-inducing HIV-1), and viral RNA load in serum as covariates. RESULTS: In the case-control study, 48% of long-term survivors were heterozygous for CCR5 delta 32 compared with 9% of progressors (odds ratio, 6.9 [95% CI, 1.9 to 24.8]). In the total study sample, CCR5 delta 32 heterozygotes had significantly delayed disease progression (P < 0.001; relative hazard, 0.4 [CI, 0.3 to 0.6]), a 1.5-fold slower decrease in CD4+ T-lymphocyte count (P = 0.01), and a 2.6-fold lower viral RNA load (P = 0.01) at approximately 2.3 years after seroconversion compared with CCR5 wild-type homozygotes. At the end of the study, both groups showed the same prevalence of syncytium-inducing HIV-1, but CCR5 delta 32 heterozygotes had a delayed conversion rate. The protective effect of CCR5 delta 32 heterozygosity was stronger in the presence of only non-syncytium-inducing HIV-1. The CCR5 genotype predicted disease progression independent of viral RNA load, CD4+ T-lymphocyte counts, T-lymphocyte function, and HIV-1 biological phenotype. CONCLUSIONS: The addition of CCR5 genotype to currently available laboratory markers may allow better estimation of the clinical course of HIV-1 infection.

Acquired Immunodeficiency Syndrome↗
PubMed1997

[Zidovudine-resistant HIV strains in untreated intravenous drug users and homosexual men in Amsterdam infected in 1996].

OBJECTIVE: To gain insight into the spread of HIV strains with different sensitivities to antiretroviral drugs prescribed in the Netherlands. DESIGN: Prospective cohort study in intravenous drug users and homosexual men. SETTING: Amsterdam, the Netherlands. METHODS: HIV negative participants in the Amsterdam cohort studies among homosexual men and intravenous drug users are tested two to three times a year for HIV antibodies. The first positive serum sample of those who seroconverted was used to determine, on the basis of the nucleotide sequence of the reverse transcriptase gene of HIV, if viruses were present with a reduced sensitivity to reverse transcriptase inhibitors. RESULTS: In 1996, 17 new HIV infections occurred (8 in homosexual men and 9 in intravenous drug users). In two new infections in homosexual men HIV strains with reduced sensitivity to zidovudine were present.

Anti-HIV Agents↗
PubMed1997

Preliminary findings of an in vitro human spleen mononuclear cell culture system for primary isolates of HIV type 1.

Acute HIV-1 infection is often manifested with a high level of viremia. The cell types and tissues/organs that contribute to the virus load are thought to be of central and peripheral lymphoreticular origin. The establishment and permissiveness of organ-based cell culture systems from spleen with laboratory strains or primary isolates of HIV-1 have not been reported. We studied unseparated splenic mononuclear cells (SMCs) and adherent cells derived from human spleen and liver in comparison with blood monocyte-derived macrophages (MDMs). Unstimulated, SMCs were highly permissive to primary lymphotropic HIV-1 and dual/macrophage-tropic isolates (which are able to replicate in both MDMs and PBMCs). Furthermore, SMCs were found to replicate virus to high titer in a rapid log-phase manner and exhibited a prolonged stationary phase of virus production, unlike PBMCs, which required conventional activation with mitogens and exhibited a much shorter period of virus production. Interestingly, the SMCs maintained themselves as a mixed phenotype of nested lymphocytes with complex and well-differentiated macrophage(s) for extended periods of time. In addition, splenic macrophages readily purified by adherence were highly permissive to a dual/macrophage-tropic primary isolate, HIV-1ADA, intermediate with two laboratory strains, HIVR-1RF and HIV-lHXB3, and least permissive to the lymphotropic primary isolate HIV-1Mr452 and two other laboratory strains, HIV-1CC and HIV-1MN. The replication of HIV-1ADA as measured by extracellular p24 was sustained for up to 7 weeks and similar to the replication patterns observed with adherent hepatic macrophages and blood-derived MDMs. This study demonstrates that exogenous stimulation is not required for infection of these cells; either adherence-isolated and/or mixed lymphoid populations can be studied together, and viable stocks can be readily prepared and cryopreserved. In addition, these cells could be used for isolating new and/or other variants of HIV-1. Thus, the use of the SMC primary in vitro cell culture system for future studies involving HIV-1 is warranted.

Adult↗