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  1 / 6 LILACS  
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Id: lil-357538
Autor: Mohabatkar, H; Kar, S. K.
Título: Prediction of exposed domains of envelope glycoprotein in Indian HIV-1 isolates and experimental confirmation of their immunogenicity in humans
Fonte: Braz. j. med. biol. res = Rev. bras. pesqui. méd. biol;37(5):675-681, May 2004. tab.
Idioma: en.
Resumo: We describe the impact of subtype differences on the seroreactivity of linear antigenic epitopes in envelope glycoprotein of HIV-1 isolates from different geographical locations. By computer analysis, we predicted potential antigenic sites of envelope glycoprotein (gp120 and gp4l) of this virus. For this purpose, after fetching sequences of proteins of interest from data banks, values of hydrophilicity, flexibility, accessibility, inverted hydrophobicity, and secondary structure were considered. We identified several potential antigenic epitopes in a B subtype strain of envelope glycoprotein of HIV-1 (IIIB). Solid- phase peptide synthesis methods of Merrifield and Fmoc chemistry were used for synthesizing peptides. These synthetic peptides corresponded mainly to the C2, V3 and CD4 binding sites of gp120 and some parts of the ectodomain of gp41. The reactivity of these peptides was tested by ELISA against different HIV-1-positive sera from different locations in India. For two of these predicted epitopes, the corresponding Indian consensus sequences (LAIERYLKQQLLGWG and DIIGDIRQAHCNISEDKWNET) (subtype C) were also synthesized and their reactivity was tested by ELISA. These peptides also distinguished HIV-1-positive sera of Indians with C subtype infections from sera from HIV-negative subjects.
Descritores: Ensaio de Imunoadsorção Enzimática
Proteína gp120 do Envelope de HIV
Proteína gp41 do Envelope de HIV
HIV-1
Imunogenética
-Índia
Limites: Humanos
Responsável: BR1.1 - BIREME


  2 / 6 LILACS  
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Id: lil-356446
Autor: Casseb, Jorge; Montanheiro, Patricia; Komninakis, Shirley; Brito, Adriana; Duarte, Alberto J. S.
Título: Human immunodeficiency virus type 1 Brazilian subtype B variant showed an increasing avidity of the anti-V3 antibodies over time compared to the subtype B US: European strain in São Paulo, Brazil
Fonte: Mem. Inst. Oswaldo Cruz;99(1):69-71, Feb. 2004. tab, graf.
Idioma: en.
Projeto: Fapesp; . CNPq.
Resumo: The Brazilian variant of human immunodeficiency virus type 1 (HIV-1) subtype B, (serotype B"-GWGR), has a tryptophan replacing the proline in position 328 the HIV-1 envelope. A longer median time period from infection to acquired immunodeficiency syndrome (AIDS) for serotype B (B"-GWGR) infected subjects compared to the B-GPGR US/European strain was reported. In a cohort study, in São Paulo city, 10 B"-GWGR patients had a statistically significant increased avidity of the anti-V3 antibodies, from 79 percent ± 33 percent to 85 percent ± 75 percent, versus from 48 percent ± 59 percent to 32 percent ± 17 percent for the 10 B-GPGR subjects (p = 0.02). The T CD4+ cells showed a mean increase of + 0.45 cells/month for the B-GPGR subjects and for B"-GWGR the slope was + 1.24 cells/month (p = 0.06), for 62 and 55 months of follow up, respectively. RNA plasma viral load decreased from 3.98 ± 1.75 to 2.16 ± 1.54 log10 in the B"-GWGR group while B-GPGR patients showed one log10 reduction in viral load from 4.09 ± 0.38 to 3.17 ± 1.47 log10 over time (p = 0.23), with a decreasing slope of 0.0042 ± log10,/month and 0.0080 ± log10/month, for B-GPGR and B"-GWGR patients, respectively (p = 0.53). Neither group presented any AIDS defining events during the study, according to Center for Diseases Control criteria. Although the sample size is small, these results may indicate that differences in the pathogenicity of the 2 HIV-1 B serotypes which co-circulate in Brazil may be correlated to the avidity of anti-V3 antibodies.
Descritores: Síndrome de Imunodeficiência Adquirida/imunologia
Afinidade de Anticorpos
Anticorpos Anti-HIV
-Síndrome de Imunodeficiência Adquirida/virologia
Brasil
Estudos de Coortes
Seguimentos
Variação Genética
Anticorpos Anti-HIV
Proteína gp120 do Envelope de HIV
RNA Viral
Sorotipagem
Carga Viral
Limites: Humanos
Masculino
Feminino
Tipo de Publ: Estudo Comparativo
Responsável: BR1.1 - BIREME


  3 / 6 LILACS  
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Id: lil-334256
Autor: Bongertz, Vera; Ouverney, Elaine Priscilla; Teixeira, Sylvia L. M; Silva-de-Jesus, Carlos; Hacker, Mariana A; Morgado, Mariza G; Bastos, Francisco I.
Título: Anti-human immunodeficiency virus-1 antibody titers in injection drug users compared to sexually infected individuals
Fonte: Mem. Inst. Oswaldo Cruz;98(2):209-212, Mar. 15, 2003. tab, graf.
Idioma: en.
Resumo: Sera from infected injection drug users (IDU) have shown to have antibodies against synthetic human immunodeficiency virus-1 (HIV-1) envelope peptides more frequently. In this study, reactivity of 48 IDU plasma were compared to 60 plasmas obtained from sexually infected individuals (S). The overall reactivity of plasma from IDU compared to S was higher, and the reactivity titers were much higher for IDU plasma than S. IDU plasma also showed a broader antibody response. The higher reactivity titers were observed mainly for the gp41 immunodominant epitope and V3 peptides corresponding to the consensus sequences of HIV-1 subtypes/variants prevalent in Brazil (B, F, C) indicating the specificity in the higher immune response of IDU
Descritores: Anticorpos Anti-HIV
Proteína gp120 do Envelope de HIV
Proteína gp41 do Envelope de HIV
Infecções por HIV
HIV-1
Fragmentos de Peptídeos
-Reações Cruzadas
Progressão da Doença
Ensaio de Imunoadsorção Enzimática
Infecções por HIV
Prognóstico
Comportamento Sexual
Abuso de Substâncias por Via Intravenosa
Limites: Humanos
Masculino
Feminino
Tipo de Publ: Estudo Comparativo
Responsável: BR1.1 - BIREME


  4 / 6 LILACS  
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Id: lil-304663
Autor: Casseb, J; Katzenstein, D; Winters, M; Brigido, L. F. M; Duarte, A. J. S; Hendry, R. M.
Título: Serotyping HIV-1 with V3 peptides: detection of high avidity antibodies presenting clade-specific reactivity
Fonte: Braz. j. med. biol. res = Rev. bras. pesqui. méd. biol;35(3):369-375, Mar. 2002. ilus, tab.
Idioma: en.
Resumo: The main objective of the present study was to assess the specificity and sensitivity of a modified assay using short synthetic peptides of the V3 region of HIV-1 gp120, which is the main target for neutralizing antibodies. Results from an enzyme immunoassay (EIA) employing a panel of synthetic peptides of HIV-1 subtypes and using urea washes to detect high avidity antibodies (AAV3) were compared with those obtained by the heteroduplex mobility assay and DNA sequencing. The EIA correctly typed 100 percent of subtype B (sensitivity = 1.0; specificity = 0.95), 100 percent of HIV-1 E samples (sensitivity = 1.0; specificity = 1.0), and 95 percent of subtype C specimens (sensitivity = 0.95; specificity = 0.94). In contrast, only 50 percent of subtype A (sensitivity = 0.5; specificity = 0.95), 60 percent of subtype D (sensitivity = 0.6; specificity = 1.0), and 28 percent of subtype F samples (sensitivity = 0.28; specificity = 0.95) were correctly identified. This approach was also able to discriminate in a few samples antibodies from patients infected with B variants circulating in Brazil and Thailand that reacted specifically. The assays described in this study are relatively rapid and simple to perform compared to molecular approaches and can be used to screen large numbers of serum or plasma samples. Moreover, the classification in subtypes (genotypes) may overestimate HIV-1 diversity and a classification into serotypes, based on antigenic V3 diversity or another principal neutralization domain, may be more helpful for vaccine development and identification of variants
Descritores: Afinidade de Anticorpos
Anticorpos Anti-HIV
Proteína gp120 do Envelope de HIV
Infecções por HIV
HIV-1
Técnicas Imunoenzimáticas
-Sequência de Aminoácidos
Sequência de Bases
Anticorpos Anti-HIV
Infecções por HIV
HIV-1
Dados de Sequência Molecular
Sensibilidade e Especificidade
Homologia de Sequência
Sorologia
Sorotipagem
Limites: Humanos
Responsável: BR1.1 - BIREME


  5 / 6 LILACS  
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Id: lil-228514
Autor: Ramos Martinez, S. L; Mendez, I; Delgado, R; Cadilla, C. L.
Título: Sequence analysis of the V1-V2 hypervariable region of the HIV-1 envelope gene from pediatric patients
Fonte: P. R. health sci. j;15(3):211-8, Sept. 1996.
Idioma: en.
Resumo: The presence of HIV-1 DNA sequence variants of pediatric AIDS patients was investigated in a two-stage polymerase chain reaction (PCR) using nested primers for the first and second (V1-V2) hypervariable regions of the proviral envelope (gp 120) gene (env1). Gel electrophoresis analysis yielded amplified DNA bands which exhibited length variations which were characteristic for each child. The PCR products were cloned and the resulting clones demonstrated inserts of different lengths in a patient and between patients. Analysis of five clones from two different patients at the level of DNA sequencing indicates an extreme heterogeneity in the V1-V2 region. DNA maximum similarity between all of the isolated clones ranged between 69 to 96 percent. Comparison between DNA sequences of the isolated clones and HIV-1 strains of other parts of the world was also performed. The highest percentage of similarity that was found with known HIV variants included the following strains: HIVADA, HIVJFL, HIVSW42, HIVSWB83, HIVTRA2, HIVWMJ22. The sequences also showed a high degree of similarity to the clade B virus HIVSF162. The analyzed HIV-1 sequences demonstrated the expected high degree of variation in the V1-V2 region of the envelope gene and in some cases that the variation between isolates from the same patient may exceed the variation between the individual clones and the reference HIV-1 strains
Descritores: DNA Viral/genética
Proteína gp120 do Envelope de HIV/genética
Infecções por HIV/virologia
HIV-1/genética
Região Variável de Imunoglobulina/genética
Análise de Sequência de DNA
-Sequência de Aminoácidos
Sequência de Bases
Variação Genética
Infecções por HIV/transmissão
Transmissão Vertical de Doenças Infecciosas
Dados de Sequência Molecular
Peso Molecular
Reação em Cadeia da Polimerase
Porto Rico
Limites: Criança
Pré-Escolar
Humanos
Lactente
Tipo de Publ: Research Support, Non-U.S. Gov't
Research Support, U.S. Gov't, P.H.S.
Responsável: BR1.1 - BIREME


  6 / 6 LILACS  
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Id: lil-223983
Autor: Casseb, J; Hong, M. A; Gonsalez, C; Brígido, L. F; Duarte, A. J. S; Michael-Hendry, R.
Título: Two variants of HIV-1 B serotype are transmitted heterosexually in Säo Paulo, Brazil
Fonte: Braz. j. med. biol. res = Rev. bras. pesqui. méd. biol;31(10):1243-6, Oct. 1998. tab.
Idioma: en.
Projeto: Fogarty AIDS International; . Universidade de Säo Paulo. Faculdade de Medicina. Hospital das Clínicas.
Resumo: HIV-1 variability may have an important impact on transmission and pathogenicity. Better characterization of the HIV epidemic in Brazil is necessary for the development of vaccine trials in this country. We analyzed sera from 108 HIV-1-infected volunteers from Säo Paulo City to determine serotype and reactivity for V3 motifs of HIV in this population, and the relationship to transmission mode. We concluded that the HIV-1 B serotype is frequent among heterosexually infected women, even in the absence of anal sex, and that two major V3 motifs, GPGR and GWGR, had similar prevalence among women (48 per cent and 52 per cent, respectively) and men (56 per cent and 44 per cent, respectively). We also observed an equal distribution of these strains regardless of their CD4+ T cell counts, clinical status, and mode of transmission. Even though V3 serology for HIV-1 subtyping is an inexpensive tool for use in developing countries, additional methods, such as heteroduplex mobility assay and direct DNA sequencing, should be included to determine HIV-1 genetic diversity.
Descritores: Heterossexualidade
Infecções por HIV/transmissão
HIV-1/classificação
-Brasil
Proteína gp120 do Envelope de HIV
Sorotipagem
Limites: Humanos
Masculino
Feminino
Adulto
Pessoa de Meia-Idade
Tipo de Publ: Revisão
Research Support, Non-U.S. Gov't
Responsável: BR1.1 - BIREME



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