RESUMO
OBJECTIVES: The EuResist expert system is a novel data-driven online system for computing the probability of 8-week success for any given pair of HIV-1 genotype and combination antiretroviral therapy regimen plus optional patient information. The objective of this study was to compare the EuResist system vs. human experts (EVE) for the ability to predict response to treatment. METHODS: The EuResist system was compared with 10 HIV-1 drug resistance experts for the ability to predict 8-week response to 25 treatment cases derived from the EuResist database validation data set. All current and past patient data were made available to simulate clinical practice. The experts were asked to provide a qualitative and quantitative estimate of the probability of treatment success. RESULTS: There were 15 treatment successes and 10 treatment failures. In the classification task, the number of mislabelled cases was six for EuResist and 6-13 for the human experts [mean±standard deviation (SD) 9.1±1.9]. The accuracy of EuResist was higher than the average for the experts (0.76 vs. 0.64, respectively). The quantitative estimates computed by EuResist were significantly correlated (Pearson r=0.695, P<0.0001) with the mean quantitative estimates provided by the experts. However, the agreement among experts was only moderate (for the classification task, inter-rater κ=0.355; for the quantitative estimation, mean±SD coefficient of variation=55.9±22.4%). CONCLUSIONS: With this limited data set, the EuResist engine performed comparably to or better than human experts. The system warrants further investigation as a treatment-decision support tool in clinical practice.
Assuntos
Sistemas Inteligentes , Infecções por HIV/tratamento farmacológico , HIV-1/efeitos dos fármacos , Bases de Dados Factuais , Feminino , Infecções por HIV/genética , Infecções por HIV/virologia , HIV-1/genética , Humanos , Masculino , Probabilidade , Resultado do Tratamento , Carga ViralRESUMO
A highly divergent HIV-1 isolate, designated YBF 30, was obtained in 1995 from a 40-year-old Cameroonian woman with AIDS. Depending on the genes studied, phylogenetic analysis showed that YBF30 branched either with SIVcpz-gab or between SIVcpz-gab and HIV-1 group M. The structural genes and tat, vpr, and nef of YBF30 are approximately equidistant from those of HIV-1 group M and SIVcpz-gab. In contrast, vif and rev are closer to HIV-1 group M, and vpu is highly divergent. Using a YBF30 V3 loop peptide enzyme immunoassay, we screened 700 HIV-1-positive sera collected in Cameroon; three reacted strongly with the YBF30 peptides and one was confirmed as being related to YBF30 by genetic analysis of a pol fragment. YBF30 is as distinct from SIVcpz-gab as it is from HIV-1 group M and can thus be considered as the prototype strain of a new human immunodeficiency virus group.
Assuntos
Síndrome da Imunodeficiência Adquirida/virologia , HIV-1/genética , Síndrome da Imunodeficiência Adquirida/epidemiologia , Adulto , Sequência de Aminoácidos , Sequência de Bases , Camarões/epidemiologia , DNA Viral , Feminino , Genoma Viral , HIV-1/classificação , HIV-1/isolamento & purificação , HIV-1/metabolismo , Humanos , Dados de Sequência Molecular , Filogenia , Receptores CCR5/metabolismo , Vírus da Imunodeficiência Símia/classificação , Vírus da Imunodeficiência Símia/genéticaRESUMO
INTRODUCTION: The influenza A (H1N1) 2009 outbreak caused death and a disruption of public health services. Rapid influenza diagnostic tests (RIDT) could be helpful to ease the triage of patients and prevent an overload of emergency and laboratory facilities. OBJECTIVES: To compare the sensitivity and specificity of the Clearview Exact Influenza A&B test and real-time reverse transcription(RT)-PCR to detect influenza A (H1N1) 2009 in a paediatric emergency department of a paediatric teaching hospital in Paris, France. METHODS: 76 children with an influenza-like illness and either severe symptoms or an underlying medical condition were prospectively recruited between July 2009 and October 2009. RIDT and RT-PCR were simultaneously performed and compared. RESULTS: Among 39 influenza A (H1N1) 2009 RT-PCR-positive children (median age 5 years), 23 Clearview Exact Influenza A&B tests were positive. Sensitivity was 59% (95% CI 42.2 to 74) and specificity was 94.6% (95% CI 80.5 to 99.1). CONCLUSIONS: This study shows a sensitivity of RIDT of 59%, in agreement with other prospective studies, which could be useful in clinical practice for diagnosis influenza A (H1N1) 2009 in children. In outbreaks of a high prevalence, such as the 2009 outbreak, this test can help to prevent an overload of public health services.
Assuntos
Surtos de Doenças , Vírus da Influenza A Subtipo H1N1 , Influenza Humana/diagnóstico , Adolescente , Criança , Pré-Escolar , Testes Diagnósticos de Rotina/normas , Feminino , Humanos , Lactente , Influenza Humana/epidemiologia , Masculino , Paris/epidemiologia , Reação em Cadeia da Polimerase/métodos , Estudos Prospectivos , Sensibilidade e EspecificidadeRESUMO
ANRS 127 was a randomized pilot trial involving naïve patients receiving two dual-boosted protease inhibitor (PI) combinations. Virological response, defined as a plasma HIV RNA level of <50 copies/ml at week 16, occurred in only 41% patients. Low baseline plasma HIV RNA level was the only significant predictor of virological response. The purpose of this study was to investigate the impact on virological response of pretherapy mutations in cleavage sites of gag, gag-pol, and the gag-pol frameshift region. The whole gag gene and protease-coding region were amplified and sequenced at baseline and at week 16 for 48 patients still on the allocated regimen at week 16. No major PI resistance-associated mutations were detected either at baseline or in the 26 patients who did not achieve virological response at week 16. Baseline cleavage site substitutions in the product of the gag open reading frame at positions 128 (p17/p24) (P = 0.04) and 449 (p1/p6(gag)) (P = 0.01) were significantly more frequent in those patients not achieving virological response. Conversely, baseline cleavage site mutation at position 437 (TFP/p6(pol)) was associated with virological response (P = 0.04). In multivariate analysis adjusted for baseline viral load, these 3 substitutions remained independently associated with virological response. We demonstrated here, in vivo, an impact of baseline polymorphic gag mutations on virological response in naïve patients receiving a combination of two protease inhibitors. However, it was not possible to link the substitutions selected under PI selective pressure with virological failure.
Assuntos
Infecções por HIV/tratamento farmacológico , Infecções por HIV/genética , Inibidores da Protease de HIV/uso terapêutico , HIV-1/genética , Mutação/genética , Produtos do Gene gag do Vírus da Imunodeficiência Humana/genética , Sequência de Aminoácidos , Inibidores da Protease de HIV/farmacologia , HIV-1/classificação , HIV-1/efeitos dos fármacos , Humanos , Dados de Sequência Molecular , Análise Multivariada , Filogenia , Homologia de Sequência de AminoácidosRESUMO
We evaluated the performance of the prototype Cobas AmpliPrep/Cobas TaqMan HIV-1 test, version 2.0, using prospective and archived clinical samples initially underquantitated by the Cobas AmpliPrep/Cobas TaqMan HIV-1 test. The performance of the new test was significantly improved, and the majority of the underquantitation observed with the first-version test was eliminated.
Assuntos
Infecções por HIV/virologia , HIV-1/isolamento & purificação , Técnicas de Diagnóstico Molecular/métodos , Kit de Reagentes para Diagnóstico , Carga Viral , HIV-1/genética , HumanosRESUMO
The etiological agent of AIDS, LAV/HTLV-III, is common in Central Africa but is not endemic in other areas of that continent. A novel human retrovirus, distinct from LAV/HTLV-III, has now been isolated from two AIDS patients from West Africa. Partial characterization of this virus revealed that it has biological and morphological properties very similar to LAV but that it differs in some of its antigenic components. Although the core antigens may share some common epitopes, the West African AIDS retrovirus and LAV differ substantially in their envelope glycoproteins. The envelope antigen of the West African virus can be recognized by serum from a macaque with simian AIDS infected by the simian retrovirus termed STLV-IIImac, suggesting that the West African AIDS virus may be more closely related to this simian virus than to LAV. Hybridization experiments with LAV subgenomic probes further established that this new retrovirus, here referred to as LAV-II, is distantly related to LAV and distinct from STLV-IIImac.
Assuntos
Síndrome da Imunodeficiência Adquirida/microbiologia , Retroviridae/isolamento & purificação , Adulto , África Ocidental , Antígenos Virais/análise , Deltaretrovirus/análise , Deltaretrovirus/genética , Deltaretrovirus/imunologia , Eletroforese em Gel de Poliacrilamida , Ensaio de Imunoadsorção Enzimática , Epitopos/análise , Humanos , Masculino , Microscopia Eletrônica , RNA Viral/análise , Retroviridae/genética , Retroviridae/imunologia , Proteínas Virais/análiseRESUMO
The presence of antibodies to lymphadenopathy-associated retrovirus (LAV) was determined by a radioimmunoprecipitation assay and by an enzyme-linked immunosorbent solid assay of sera from Zairian patients with the acquired immune deficiency syndrome (AIDS) in 1983. Thirty-five of 37 patients (94 percent) and 32 of 36 patients (88 percent), respectively, were seropositive by the two tests. In a control group of 26 patients, six (23 percent) showed positive results in these tests. Of these six control patients, five had clinically demonstrable infectious diseases and a low ratio of T4 to T8 lymphocytes. In addition, sera collected from a control group of Zairian mothers in 1980 were positive for LAV in 5 of 100 cases. Other serologic data suggest that LAV was present as early as 1977 in Zaire.
Assuntos
Síndrome da Imunodeficiência Adquirida/imunologia , Anticorpos Antivirais/análise , Doenças Linfáticas/microbiologia , Retroviridae/imunologia , República Democrática do Congo , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Masculino , Radioimunoensaio , Linfócitos T Auxiliares-Indutores/citologia , Linfócitos T Reguladores/citologiaRESUMO
OBJECTIVES: We investigated the in vitro phenotypic susceptibility of HIV-2 isolates from integrase inhibitor (INI)-naive patients to INIs and its relation to HIV-2 integrase gene polymorphism. METHODS: We determined the phenotypic susceptibility to raltegravir and elvitegravir of co-cultured isolates obtained from the HIV-2 ROD reference strain and from 14 clinical isolates. IC(50) values were compared with those for HIV-1 reference strains. HIV-2 integrase gene polymorphism was assessed in isolates from 52 INI-naive patients enrolled in the French HIV-2 cohort. RESULTS: Median raltegravir and elvitegravir IC(50) values for the 14 clinical HIV-2 isolates were 2.4 and 0.7 nM, respectively, and were similar to those observed for HIV-2 ROD and HIV-1 reference strains. Overall, 38% of HIV-2 integrase amino acids were polymorphic. The catalytic triad DDE and the HHCC and RKK motifs were fully conserved, at the same genomic positions as described in HIV-1. In subtype B isolates, the total length of the integrase gene varied, owing to the presence of stop codons at positions 288, 294, 297 and 302. Fourteen of the positions associated with substitutions conferring INI resistance in HIV-1 were polymorphic in HIV-2. CONCLUSIONS: Despite 40% heterogeneity between the HIV-1 and HIV-2 integrase genes, the phenotypic susceptibility of clinical HIV-2 isolates to INIs was similar to that of HIV-1. This new class of antiretroviral drugs thus represents a novel therapeutic possibility for HIV-2-infected patients who otherwise have few treatment options.
Assuntos
Farmacorresistência Viral , Integrase de HIV/genética , HIV-2/efeitos dos fármacos , Inibidores de Integrase/farmacologia , Polimorfismo Genético , Pirrolidinonas/farmacologia , Quinolonas/farmacologia , Sequência de Aminoácidos , Substituição de Aminoácidos/genética , Domínio Catalítico , Códon sem Sentido , Estudos de Coortes , Sequência Conservada , França , Infecções por HIV/virologia , HIV-1/efeitos dos fármacos , HIV-2/isolamento & purificação , Humanos , Concentração Inibidora 50 , Testes de Sensibilidade Microbiana , Dados de Sequência Molecular , Mutação de Sentido Incorreto , Raltegravir PotássicoRESUMO
BACKGROUND: We developed clinically relevant genotypic scores for resistance to fosamprenavir/ritonavir in HIV-1 protease inhibitor (PI)-experienced patients. METHODS: PI-experienced patients with virological failure receiving fosamprenavir/ritonavir as the sole PI for at least 3 months and with detectable fosamprenavir plasma levels were included. The impact of baseline protease mutations on virological response (VR, i.e. decrease in plasma HIV-1 RNA between baseline and month 3) was analysed using the Mann-Whitney test. Mutations with prevalence >10% and P value <0.10 were retained. The Jonckheere-Terpstra test was used to select the combination of mutations most strongly associated with VR. The association between score and VR was assessed by multivariate backward regression. RESULTS: In the 73 patients included, the median baseline HIV-1 RNA was 4.6 log(10) copies/mL (range: 2.7-6.9) and the mean decrease at month 3 was -1.07 +/- 1.40 log(10) copies/mL. Ninety per cent of the patients were infected by HIV-1 subtype B variants. Two fosamprenavir/ritonavir mutation scores were constructed: score A (L10F/I/V + L33F + M36I + I54L/M/V/A/T/S + I62V + V82A/F/C/G + I84V + L90M) was based only on mutations associated with a worse VR, whereas score B (L10FIV + L33F + M36I + I54L/M/V/A/T/S + A71V - V77I - N88S + L90M) also took into account favourable mutations. Both scores were independent predictors of VR, however, co-administration of tenofovir was associated with a worse VR and the presence of the N88S protease mutation and co-administration of enfuvirtide with a better VR. CONCLUSIONS: These clinically validated mutation scores should be of interest for the clinical management of PI-experienced patients. The fosamprenavir/ritonavir score A was introduced in the 2006 ANRS algorithm along with isolated mutations I50V and V32I + I47V.
Assuntos
Carbamatos/uso terapêutico , Farmacorresistência Viral , Infecções por HIV/virologia , Inibidores da Protease de HIV/uso terapêutico , HIV-1/efeitos dos fármacos , HIV-1/genética , Mutação de Sentido Incorreto , Organofosfatos/uso terapêutico , Ritonavir/uso terapêutico , Sulfonamidas/uso terapêutico , Adulto , Substituição de Aminoácidos/genética , Carbamatos/farmacologia , Feminino , Furanos , Genótipo , Infecções por HIV/tratamento farmacológico , Inibidores da Protease de HIV/farmacologia , HIV-1/classificação , HIV-1/isolamento & purificação , Humanos , Masculino , Pessoa de Meia-Idade , Organofosfatos/farmacologia , RNA Viral/sangue , RNA Viral/genética , Ritonavir/farmacologia , Sulfonamidas/farmacologia , Carga ViralRESUMO
Hepatitis C (HCV) molecular epidemiology is documented poorly in central African countries. In response to this, a population-based study of 319 consenting adults resident in a remote village of Gabon was undertaken (mean age: 38 years; age range: 13-85+; sex ratio: 0.74). Screening for anti-HCV antibodies was performed using ELISA and recombinant immunoblot assay. Seropositive samples were assessed further with viral load and genotyping techniques. Sixty-six (20.7%) individuals were HCV seropositive. Viral loads ranged from 600 to 24.9 million IU/ml (median: 372,500). Seroprevalence and viral loads increased significantly with age (P < 10(-5) and P < 0.003, respectively). HCV sequences of the 5'UTR genome region were obtained from 60 (90.9%) samples and NS5B region sequences were obtained from 22 (36.6%) samples. All strains belonged to subtypes of genotype 4: 4e (72.7%), 4c (13.6%), 4p (4.5%), 4r (4.5%) and one unclassified genotype 4 strain. Evolutionary analysis of the subtype 4e sequences indicates a period of raised transmission during the early twentieth century.
Assuntos
Hepacivirus/classificação , Hepacivirus/isolamento & purificação , Hepatite C/epidemiologia , Hepatite C/virologia , Regiões 5' não Traduzidas , Adolescente , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Ensaio de Imunoadsorção Enzimática , Feminino , Gabão/epidemiologia , Genótipo , Hepacivirus/genética , Anticorpos Anti-Hepatite C/sangue , Humanos , Immunoblotting , Masculino , Pessoa de Meia-Idade , Filogenia , RNA Viral/genética , População Rural , Análise de Sequência de DNA , Estudos Soroepidemiológicos , Carga Viral , Proteínas não Estruturais Virais/genéticaRESUMO
Plasma drug-resistant minority human immunodeficiency virus type 1 variants (DRMVs) increase the risk of virological failure to first-line non-nucleoside reverse transcriptase inhibitor antiretroviral therapy (ART). The origin of DRMVs in ART-naive patients, however, remains unclear. In a large pan-European case-control study investigating the clinical relevance of pre-existing DRMVs using 454 pyrosequencing, the six most prevalent plasma DRMVs detected corresponded to G-to-A nucleotide mutations (V90I, V106I, V108I, E138K, M184I and M230I). Here, we evaluated if such DRMVs could have emerged from apolipoprotein B mRNA editing enzyme, catalytic polypeptide 3G/F (APOBEC3G/F) activity. Out of 236 ART-naive subjects evaluated, APOBEC3G/F hypermutation signatures were detected in plasma viruses of 14 (5.9%) individuals. Samples with minority E138K, M184I, and M230I mutations, but not those with V90I, V106I or V108I, were significantly associated with APOBEC3G/F activity (Fisher's P < 0.005), defined as the presence of > 0.5% of sample sequences with an APOBEC3G/F signature. Mutations E138K, M184I and M230I co-occurred in the same sequence as APOBEC3G/F signatures in 3/9 (33%), 5/11 (45%) and 4/8 (50%) of samples, respectively; such linkage was not found for V90I, V106I or V108I. In-frame STOP codons were observed in 1.5% of all clonal sequences; 14.8% of them co-occurred with APOBEC3G/F signatures. APOBEC3G/F-associated E138K, M184I and M230I appeared within clonal sequences containing in-frame STOP codons in 2/3 (66%), 5/5 (100%) and 4/4 (100%) of the samples. In a re-analysis of the parent case control study, the presence of APOBEC3G/F signatures was not associated with virological failure. In conclusion, the contribution of APOBEC3G/F editing to the development of DRMVs is very limited and does not affect the efficacy of non-nucleoside reverse transcriptase inhibitor ART.
Assuntos
Citidina Desaminase/genética , Citosina Desaminase/genética , Farmacorresistência Viral , Infecções por HIV/virologia , HIV-1/genética , Mutação , Desaminase APOBEC-3G , Terapia Antirretroviral de Alta Atividade , Estudos de Casos e Controles , Feminino , Infecções por HIV/tratamento farmacológico , Infecções por HIV/metabolismo , Humanos , Masculino , Edição de RNA , RNA Viral/genética , RNA Viral/metabolismo , Inibidores da Transcriptase Reversa/uso terapêuticoRESUMO
BACKGROUND: In HIV-infected patients on first-line antiretroviral therapy, the significance of intermittent viremia and their relationship with drug resistance remain unclear. OBJECTIVE: To study the virological characteristics of intermittent viremia (IV) and the association between IV and later virological failure (VF) in patients on a first-line, PI-containing therapy. STUDY DESIGN: Antiretroviral-naive patients were enrolled in the APROVIR substudy of the prospective, multicenter APROCO cohort at the time they initiated a PI-containing therapy and were followed-up at month 1 and every 2 months. IV was defined as plasma HIV-1 RNA > 500 copies/ml on a single specimen. VF were defined as: (1) viral rebound on two consecutive plasma specimens with HIV-1 RNA > 500 copies/ml after an initial response below 500 copies/ml, or (2) persistence of plasma HIV-1 RNA> or =500 copies/ml during the first year of follow-up. Genotypic resistance analysis was performed at baseline and at the time of IV. PI plasma concentrations were determined at the time of IV. RESULTS: IV was found in 20/219 patients in a 2 years follow-up. The occurrence of IV in the first year of therapy was associated with a higher risk of virological failure during the second year (p = 0.03). Genotypic resistance at the time of IV was found in only 4/16 patients and was not predictive of a subsequent virological failure. PI plasma levels suggested lack of adherence in 50% of patients with IV. CONCLUSION: The occurrence of IV > 500 copies/ml among patients on first-line, PI-containing ART is suggestive of a lack of adherence rather than the selection of resistant variants and should lead to an intensification of adherence monitoring in order to reduce the risk of subsequent VF.
Assuntos
Fármacos Anti-HIV/uso terapêutico , Farmacorresistência Viral/genética , Infecções por HIV/tratamento farmacológico , Inibidores da Protease de HIV/uso terapêutico , Inibidores da Transcriptase Reversa/uso terapêutico , Viremia/virologia , Quimioterapia Combinada , Infecções por HIV/virologia , HIV-1/efeitos dos fármacos , HIV-1/enzimologia , HIV-1/genética , HIV-1/fisiologia , Humanos , Cooperação do Paciente , RNA Viral/sangue , Carga Viral , Viremia/tratamento farmacológicoRESUMO
BACKGROUND: To assess the efficacy and safety of the triple NRTI combination of abacavir (ABC), lamivudine (3TC), and tenofovir (TDF) in a once-daily regimen. METHOD: 38 HIV-naive patients (pts) were treated in a prospective open-arm study over 48 weeks (W48). Virological failure was defined as never achieving plasma HIV-1 RNA < 400 copies/mL or rebound of > or = 0.7 log10. RESULTS: 12/36 (33%) pts had virologic failure at W24 and 10 additional pts had HIV RNA > 50 copies/mL at W12 or W24. There was a significant association between baseline viral load (VL) and virologic failure in 0%, 29%, and 64% pts with baseline VL levels < 4, 4-5, and > 5 log10 copies/mL, respectively (p = .014). 76% of pts developed K65R and M184V/I mutations by W24, and 19% developed M184V/I alone. At W4, 86% of pts had adequate plasma Cmin for the 3 drugs. 14 pts with K65R and M184V/I were given a rescue therapy with a successful outcome (< 50 copies/mL; median follow-up 48 weeks). CONCLUSION: Convergent genetic pathway to resistance, in conjunction with lower antiretroviral potency, may explain the high rate of selection K65R and M184V mutations. These mutations did not appear to have a negative effect on rescue therapy with a variety of regimens.
Assuntos
Didesoxinucleosídeos/administração & dosagem , Infecções por HIV/tratamento farmacológico , HIV-1/genética , Lamivudina/administração & dosagem , Inibidores da Transcriptase Reversa/administração & dosagem , Adulto , Terapia Antirretroviral de Alta Atividade/métodos , Contagem de Linfócito CD4 , Didesoxinucleosídeos/sangue , Feminino , Genótipo , Infecções por HIV/sangue , Infecções por HIV/virologia , Humanos , Lamivudina/sangue , Masculino , Pessoa de Meia-Idade , Cooperação do Paciente , Projetos Piloto , Estudos Prospectivos , RNA Viral/sangue , Inibidores da Transcriptase Reversa/sangueRESUMO
PIP: The authors review advances in HIV-2 research since their last review of the subject, and summarize the current epidemiology of HIV-1 and HIV-2 infections and AIDS in West Africa. West Africa is considered to be comprised of those countries below the Sahara which belong to subregion 1 of the Africa Region as defined by the World Health Organization. Widely varying patterns of disease distribution exist across these countries. The epidemic spread of HIV-1 and HIV-2 in the region is recent, but these infections now occur throughout West Africa. The distribution of the two viral infections is both heterogenous and unstable. It is not clear whether social or biological reasons, or both, account for the apparently less successful epidemic spread of HIV-2. Important epidemiologic questions concerning HIV-2 which await resolution are its incubation period for disease and its efficiency of transmission compared with HIV-1. The authors note that for public health purposes, the two infections should be approached in the same fashion.^ieng
Assuntos
Infecções por HIV/epidemiologia , HIV-1 , HIV-2 , África Ocidental/epidemiologia , HumanosRESUMO
In central equatorial Africa the frequency of uninterpretable or atypical Western blots (WB)--ie. antibodies to gag proteins only--can represent up to 50% of enzyme-linked immunosorbent assay (ELISA)-positive samples. To date the significance of such serology remains unknown. Nevertheless, an unusual HIV-1 strain has been isolated from the blood of a healthy Gabonese individual who presented an atypical WB. This virus, identified as isolated HIV-1OYl, grew to low titres of reverse transcriptase activity (less than 50,000 cpm/ml) and was not obviously cytopathic. Radioimmunoprecipitation and peptide ELISA studies indicated that the lack of env-specific reactivity was probably due to the absence of antibodies to the viral glycoproteins, rather than the virus encoding a highly divergent envelope protein. Molecular cloning and sequencing of the provirus proved it to be a string of HIV-1 which was genetically closer to European and North American than to African strains. Furthermore the envelope protein sequence contained all the features of a typical HIV-1 env gene. However, the tat gene derived from the proviral clone was functionally defective. Site-directed mutagenesis of this gene showed that this was due to the substitution of an essential cysteine residue for a serine. Polymerase chain reaction amplification of the tat gene, as well as parts of the gag and env gene sequences of HIV-1OYl, showed that essentially all of the proviruses were defective. These data emphasize the need to view HIV isolates as populations of distinct genomes capable of complementing each other.
Assuntos
Síndrome da Imunodeficiência Adquirida/microbiologia , Genes Virais , Genes env , Genes gag , Genes tat , HIV-1/genética , Síndrome da Imunodeficiência Adquirida/diagnóstico , Sequência de Aminoácidos , Sequência de Bases , Western Blotting , Gabão , Produtos do Gene env/genética , Produtos do Gene gag/genética , Produtos do Gene tat/genética , Humanos , Dados de Sequência Molecular , Reação em Cadeia da Polimerase , Provírus/genética , Homologia de Sequência do Ácido Nucleico , Ativação Transcricional , Produtos do Gene tat do Vírus da Imunodeficiência HumanaRESUMO
OBJECTIVE: To evaluate the serological consequences of HIV-1 group M diversity we studied the ability of screening tests to detect anti-HIV antibodies in early seroconverters infected by different HIV subtypes. SETTING: Virology Department, Bichat-Claude Bernard Hospital, Paris, France. DESIGN AND METHODS: Symptomatic patients with serial samples and with infective strains characterized by heteroduplex mobility assay. In each case, two sera were selected. The first (pre-seroconversion sample) was the last p24 antigen-positive/Western blot-non-reactive sample. The second (seroconversion sample) was the first Western blot-reactive sample. One second-generation enzyme immunoassay (EIA; Abbott) based on anti-human immunoglobulin (Ig) G-conjugate and three third generation EIA (Abbott; Enzygnost; Genscreen) based on the double antigen sandwich principle, detecting IgM and IgG, were used. RESULTS: Ten patients had subtype B strains and nine had non-B strains (seven were A, one E and one G). The Abbott third-generation test was more sensitive than the second generation test for pre-seroconversion subtype B samples (nine versus four out of 10; P < 0.05), but not for non-B subtypes; only two of the nine non-B sera tested were positive by both EIA. Positivity rates and optical densities differed (P < 0.05) between B and non-B subtypes in all third-generation EIA. There was no significant difference between the subtype B and non-B groups with regard to the interval between the pre-seroconversion sample and the seroconversion sample (subtype B, 6.7 +/- 2.6 days; non-B, 5.2 +/- 1.7 days). No significant difference in positivity rates and optical densities were found between B and non-B subtypes in these seroconversion samples. CONCLUSION: The shorter time since HIV infection required for sera to become reactive in third-generation EIA screening tests is due to better sensitivity for subtype B strains only. These results stress the importance of strict donor selection, the need to test screening kits against large panels of all subtypes, and the place of p24 antigen testing in closing the window of seroconversion.
Assuntos
Anticorpos Antivirais/análise , Soropositividade para HIV/diagnóstico , HIV-1/isolamento & purificação , Anticorpos Antivirais/sangue , Proteína do Núcleo p24 do HIV/imunologia , Soropositividade para HIV/sangue , Soropositividade para HIV/imunologia , HIV-1/imunologia , Humanos , Técnicas Imunoenzimáticas , Imunoglobulina G/sangue , Imunoglobulina M/sangueRESUMO
OBJECTIVE: To evaluate changes in serum HIV p24-antigen levels in a subset of patients who participated in a European/Australian double-blind, placebo-controlled trial evaluating the efficacy of zidovudine (250 mg every 6 h) alone or in combination with acyclovir (800 mg every 6 h) in patients with AIDS, AIDS-related complex (ARC) or Kaposi's sarcoma (KS). DESIGN: Double-blind, placebo-controlled randomized clinical trial of less than or equal to 6 months' therapy. SETTING: Samples were obtained from patients attending teaching hospital outpatient clinics in seven European countries and Australia. SUBJECTS: One hundred and ninety-seven HIV-infected patients (60 with AIDS and 137 with ARC or KS). MAIN OUTCOME MEASURES: Serum HIV p24-antigen levels measured using the Abbott HIV solid-phase enzyme immunoassay. RESULTS: Of 76 ARC/KS patients who were initially HIV p24-antigen-positive, one out of 25 randomized to placebo, eight out of 23 to zidovudine and 11 out of 28 to the zidovudine/acyclovir combination became antigen-negative. The proportion of patients who became antigen-negative was significantly higher in both the zidovudine group (P = 0.016) and the zidovudine/acyclovir group (P = 0.004), compared with the placebo group. There were no statistical differences between the zidovudine and the zidovudine/acyclovir groups. During the trial p24-antigen levels in the zidovudine-treated patients reached their minimum after 4-8 weeks of therapy, and tended to increase gradually thereafter. Disease progression occurred irrespective of whether p24-antigen levels declined during therapy. No association between p24-antigen responses to therapy and baseline disease stage, Karnofsky score or baseline CD4 cell count was detectable. CONCLUSION: Acyclovir does not potentiate the effect of zidovudine on p24-antigen levels. Change in antigen level in response to antiviral therapy needs further investigation before it is used as a surrogate marker for clinical efficacy of antiviral therapy.
Assuntos
Complexo Relacionado com a AIDS/tratamento farmacológico , Síndrome da Imunodeficiência Adquirida/tratamento farmacológico , Aciclovir/uso terapêutico , Proteína do Núcleo p24 do HIV/sangue , Zidovudina/uso terapêutico , Complexo Relacionado com a AIDS/imunologia , Síndrome da Imunodeficiência Adquirida/imunologia , Aciclovir/farmacologia , Método Duplo-Cego , Quimioterapia Combinada , Proteína do Núcleo p24 do HIV/efeitos dos fármacos , Humanos , Zidovudina/farmacologiaRESUMO
OBJECTIVE: To compare two published methods for determining plasma viraemia in HIV-seropositive patients, with reference to a cellular viraemia assay. PATIENTS, PARTICIPANTS: Three patient groups were defined according to CD4 cell count: group I, less than 200 x 10(6)/l (23 patients); group II, 200-500 x 10(6)/l (18 patients); and group III, greater than 500 x 10(6)/l (13 patients). METHODS: The two reported methodologies were applied to all fresh samples, simultaneously and on the same day. RESULTS: The two techniques did not differ significantly in the detection of plasma viraemia: 82.3% of group I patients and 55% of group II patients were positive, while all group III patients were negative. Cellular viraemia was positive for 96% of the overall population. CONCLUSIONS: These results, obtained in a network of seven French laboratories involved in clinical trials, confirm that both plasma viraemia and cellular viraemia are useful virological markers.
Assuntos
Sorodiagnóstico da AIDS/métodos , Soropositividade para HIV/sangue , HIV/isolamento & purificação , Linfócitos T CD4-Positivos , Soropositividade para HIV/imunologia , Soropositividade para HIV/microbiologia , Humanos , Contagem de LeucócitosRESUMO
OBJECTIVE: To assess the reproducibility of and factors associated with HIV detection in cervicovaginal secretions (CVS). DESIGN: Longitudinal study of 43 HIV-1-infected pregnant women in Paris. METHODS: HIV DNA was detected in peripheral blood mononuclear cells (PBMC) by Amplicor and gag nested polymerase chain reaction (PCR) assays. The HIV genotype was determined by heteroduplex mobility assay. Amplicor and gag nested PCR assays were performed on serial CVS samples for HIV DNA detection, and the HIV Monitor test was used for HIV RNA detection in plasma and CVS. RESULTS: A total of 144 CVS samples were collected from the women included in the study. HIV-1 DNA was detected in 36 (25%) of the 144 samples, from 16 (37.2%) of the 43 women. Results of HIV-1 DNA detection were concordant in the first two samples in 27 (84.4%) of the 32 women with at least two CVS samples. The last CVS sample collected in each woman was HIV-1 DNA-positive in 13 (30.2%) of the 43 women. Three factors were found to be independently associated with HIV-1 DNA detection in CVS: HIV-1 subtype B, absence of zidovudine therapy, and microbial cervicovaginal infection. HIV RNA was detected in CVS from 10 (23.3%) out of 43 women and correlated with DNA detection in the same sample and HIV RNA detection in plasma. CONCLUSIONS: DNA and RNA PCR can be used to detect HIV in cells and supernatants of CVS. These techniques may be useful in cohort studies to investigate HIV transmission and to evaluate the efficacy of antiretroviral drugs to reduce HIV excretion.
Assuntos
Colo do Útero/virologia , Infecções por HIV/virologia , HIV-1/isolamento & purificação , Complicações Infecciosas na Gravidez/virologia , Vagina/virologia , Adulto , Contagem de Linfócito CD4 , Colo do Útero/metabolismo , DNA Viral/análise , Feminino , Infecções por HIV/sangue , Infecções por HIV/tratamento farmacológico , Infecções por HIV/transmissão , HIV-1/efeitos dos fármacos , HIV-1/genética , Humanos , Recém-Nascido , Transmissão Vertical de Doenças Infecciosas , Estudos Longitudinais , Pessoa de Meia-Idade , Gravidez , RNA Viral/sangue , Vagina/metabolismoRESUMO
OBJECTIVE: To study the distribution of HIV-1 subtypes in France and to describe the characteristics of patients infected with non-B subtypes. METHODS: All adults who tested HIV-1 positive on Western blot for the first time in one of the participating laboratories between September 1996 and March 1998 were eligible, whether or not they had been diagnosed previously elsewhere. Data on age, sex, country of birth, HIV-transmission group, dates of the last negative and first positive HIV test and clinical stage were collected. Serotyping was performed with a peptide subtype-specific enzyme immunoassay on each plasma sample and genotyping with heteroduplex mobility assay on each non-B serotype-infected patient. Patients characteristics were compared in B and non-B subtypes. RESULTS: Of the 2168 HIV-positive patients included by 32 laboratories, subtype,results were available for 2042. Among those, 73.4% were men, 12.2% born in sub-Saharan Africa, 41.5% infected through heterosexual contact and 67.6% in CDC stage A. Among the 2042 patients, 1 725 (84.5%) were infected with B subtype. Among the 317 non-B subtypes, subtype A was predominant (66.9%); all other subtypes (C, D, E, F, G, H, O) were present. Factors independently associated with a non-B subtype were to be included in the Paris area [adjusted odds ratio (aOR), 1.6; 95% confidence interval (CI), 1.1-2.3], to be born in sub-Saharan Africa (aOR, 26.0; 95% CI, 17.5-37.8) and to be infected through heterosexual contact (aOR, 4.2; 95% CI, 2.8-6.4). CONCLUSIONS: In France, although B subtype is still predominant, all non-B subtypes are now present. The diversity of HIV strains may affect diagnostic tests and clinical practice, especially viral load measurements. Moreover, the decreased susceptibility of non-B subtypes to antiretroviral drugs emphasizes the importance of surveillance of HIV diversity.