Phylogeographic Analysis of HIV-1 Subtype C Dissemination in Southern Brazil

The HIV-1 subtype C has spread efficiently in the southern states of Brazil (Rio Grande do Sul, Santa Catarina and Paraná). Phylogeographic studies indicate that the subtype C epidemic in southern Brazil was initiated by the introduction of a single founder virus population at some time point between 1960 and 1980, but little is known about the spatial dynamics of viral spread. A total of 135 Brazilian HIV-1 subtype C pol sequences collected from 1992 to 2009 at the three southern state capitals (Porto Alegre, Florianópolis and Curitiba) were analyzed. Maximum-likelihood and Bayesian methods were used to explore the degree of phylogenetic mixing of subtype C sequences from different cities and to reconstruct the geographical pattern of viral spread in this country region. Phylogeographic analyses supported the monophyletic origin of the HIV-1 subtype C clade circulating in southern Brazil and placed the root of that clade in Curitiba (Paraná state). This analysis further suggested that Florianópolis (Santa Catarina state) is an important staging post in the subtype C dissemination displaying high viral migration rates from and to the other cities, while viral flux between Curitiba and Porto Alegre (Rio Grande do Sul state) is very low. We found a positive correlation (r2 = 0.64) between routine travel and viral migration rates among localities. Despite the intense viral movement, phylogenetic intermixing of subtype C sequences from different Brazilian cities is lower than expected by chance. Notably, a high proportion (67%) of subtype C sequences from Porto Alegre branched within a single local monophyletic sub-cluster. These results suggest that the HIV-1 subtype C epidemic in southern Brazil has been shaped by both frequent viral migration among states and in situ dissemination of local clades

Anti-human immunodeficiency virus type 1 humoral immune response and highly active antiretroviral treatment

Submitted by Fábio Marques ([email protected]) on 2019-01-15T16:09:48Z No. of bitstreams: 1 Anti-human immunodeficiency_Beatriz_Grinsztejn_INI_Lapclin-AIDS_2007.pdf: 199816 bytes, checksum: 0aebf30c8963e60747c7469c9aafe153 (MD5)Approved for entry into archive by Janaína Nascimento ([email protected]) on 2019-01-17T22:17:16Z (GMT) No. of bitstreams: 1 Anti-human immunodeficiency_Beatriz_Grinsztejn_INI_Lapclin-AIDS_2007.pdf: 199816 bytes, checksum: 0aebf30c8963e60747c7469c9aafe153 (MD5)Made available in DSpace on 2019-01-17T22:17:16Z (GMT). No. of bitstreams: 1 Anti-human immunodeficiency_Beatriz_Grinsztejn_INI_Lapclin-AIDS_2007.pdf: 199816 bytes, checksum: 0aebf30c8963e60747c7469c9aafe153 (MD5) Previous issue date: 2007Fundação Oswaldo Cruz. Instituto de Pesquisa Clínica Evandro Chagas. Rio de Janeiro, RJ, Brasil.Fundação Oswaldo Cruz. Instituto de Pesquisa Clínica Evandro Chagas. Rio de Janeiro, RJ, Brasil.Fundação Oswaldo Cruz. Instituto de Pesquisa Clínica Evandro Chagas. Rio de Janeiro, RJ, Brasil.Fundação Oswaldo Cruz. Instituto de Pesquisa Clínica Evandro Chagas. Rio de Janeiro, RJ, Brasil.Fundação Oswaldo Cruz. Instituto de Pesquisa Clínica Evandro Chagas. Rio de Janeiro, RJ, Brasil.Fundação Oswaldo Cruz. Instituto de Pesquisa Clínica Evandro Chagas. Rio de Janeiro, RJ, Brasil.Fundação Oswaldo Cruz. Instituto de Pesquisa Clínica Evandro Chagas. Rio de Janeiro, RJ, Brasil.Fundação Oswaldo Cruz. Instituto de Pesquisa Clínica Evandro Chagas. Rio de Janeiro, RJ, Brasil.Highly active antiretroviral treatment (HAART) of human immunodeficiency type 1 (HIV-1) infection is very effective in controlling infection, but elimination of viral infection has not been achieved as yet, and upon treatment interruption an immediate rebound of viremia is observed. A combination of HAART with an immune stimulation might allow treatment interruption without this rebounding viremia, as the very low viremias observed with successful HAART may be insufficient to permit maintenance of a specific anti-HIV-1 immune response. The objective of this study was to compare the humoral immune response of individuals undergoing successful HAART (NF=no failure) with that of individuals with evidence of failure of therapy (FT) and to verify if the viremia peaks observed in individuals with therapy failure would act as a specific stimulus for the humoral anti-HIV-1 immune response. Antibodies binding to gp120 V3 genotype consensus peptides were more frequently observed for FT, mainly against peptides corresponding to sequences of genotypes prevalent in the Rio de Janeiro city area, B and F. HIV-1 neutralization of HIV-1 IIIB and of four primary isolates from Rio de Janeiro was less frequently observed for plasma from the NF than the FT group, but this difference was more expressive when plasma from individuals with detectable viremia were compared to that of individuals with undetectable viral loads in the year before sample collection. Although statistically significant differences were observed only in some specific comparisons, the study indicates that presence of detectable viremia may contribute to the maintenance of a specific anti-HIV-1 humoral immune response

Anti-human immunodeficiency virus type 1 humoral immune response and highly active antiretroviral treatment

Highly active antiretroviral treatment(HAART) of human immunodeficiency type 1 (HIV-1) infection is very effective in controlling infection, but elimination of viral infection has not been achieved as yet, and upon treatment interruption an immediate rebound of viremia is observed. A combination of HAART with an immune stimulation might allow treatment interruption without this rebounding viremia, as the very low viremias observed with successful HAART may be insufficient to permit maintenance of a specific anti-HIV-1 immune response. The objective of this study was to compare the humoral immune response of individuals undergoing successful HAART(NF=no failure) with that of individuals with evidence of failure of therapy (FT) and to verify if the viremia peaks observed in individuals with therapy failure would act as a specific stimulus for the humoral anti-HIV-1 immune response. Antibodies binding to gp120 V3 genotype consensus peptides were more frequently observed for FT, mainly against peptides corresponding to sequences of genotypes prevalent in the Rio de Janeiro city area, B and F. HIV-1 neutralization of HIV-1 IIIB and of four primary isolates from Rio de Janeiro was less frequently observed for plasma from the NF than the FT group, but this difference was more expressive when plasma from individuals with detectable viremia were compared to that of individuals with undetectable viral loads in the year before sample collection. Although statistically significant differences were observed only in some specific comparisons, the study indicates that presence of detectable viremia may contribute to the maintenance of a specific anti-HIV-1 humoral immune response

Genetic diversity and drug resistance of HIV-1 among infected pregnant women newly diagnosed in Luanda, Angola

Project Pró-África CNPq n˚ 440145/2015-5Monitoring genetic diversity and drug resistance mutations (DRMs) is critical for understanding HIV epidemiology. Here, we report HIV-1 genetic diversity and DRMs in blood samples from 42 HIV-positive pregnant women naive to antiretroviral therapy (ART), in Luanda. The samples were subjected to nested-PCR, followed by sequencing of the HIV-1 pol gene, targeting the protease and reverse transcriptase fragments. HIV-1 diversity was analyzed using the REGA HIV-1 subtyping tool and DRMs were identified using the Calibrated Population Resistance tool. A total of 34 sequences were obtained. The data revealed wide HIV-1 subtypes heterogeneity, with subtype C (38%, 13/34) the most frequent, followed by the subtypes F1 (18%, 6/34), A1 (9%, 3/34), G (9%, 3/34), D (6%, 2/34) and H (3%, 1/34). In addition, recombinants strains were detected, with CRF02_AG (6%, 2/34) the most frequent, followed by CRF37_cpx, F1/C, A1/G, and H/G, all with 3% (1/34). A total of 6/34 (18%) of the sequences presented DRMs. The non-nucleoside reverse transcriptase inhibitors presented 15% (5/34) of resistance. Moreover, 1/34 (3%) sequence presented resistance against both non-nucleoside reverse transcriptase inhibitors and nucleoside reverse transcriptase inhibitors, simultaneously. Despite the small sample size, our results suggest the need to update currently used ART regimens. Surveillance of HIV-1 subtypes and DRMs are necessary to understand HIV epidemiology and to guide modification of ART guidelines in Angola.info:eu-repo/semantics/publishedVersio

Evaluation of enzyme-linked immunosorbent and alternative assays for detection of HIV antibodies using panels of Brasilian sera

Os soros de 472 brasileiros, confirmados como sendo positivos ou negativos em relação à presença de anticorpos anti-HIV e compreendendo todo o espectro clínico da infecção, foram utilizados na avaliação de seis ensaios imunoenzimáticos comerciais (ELISA), bem como de quatro testes alternativos tais como imunofluorescência indireta (IFI), hemaglutinação passiva (HP), dot blot e Karpas AIDS cell test. As sensibilidades variaram de 100% (ELISA Abbott e Roche) a 84,2% (HP) e as especificidades variaram de 99,3% (IFI) a 80,2% (HP). A sensibilidade e especificidade da HP e a sensibilidade do Karpas AIDS cell test foram significativamente menores que os outros ensaios. Embora a IFI e o dot blot tivessem apresentado uma boa sensibilidade e especificidade, os ensaios imunoenzimáticos (ELISA) foram mais adequados para serem utilizados em triagem quando outros parâmetros tais como facilidade de leitura e interpretação dos resultados e duração dos ensaios foram considerados.Sera from 472 Brazilian subjects, confirmed to be either positive or negative for HIV antibodies and comprising the total clinical spectrum of HIV infection, were utilized in the evaluation of six commercially available enzyme-linked immunosorbent assays (ELISA), as well as of four alternative assays, namely indirect immunofluorescence (IIF), passive hemagglutination (PHA), dot blot and Karpas AIDS cell test. The sensitivities ranged from 100% (Abbott and Roche ELISA) to 84.2% (PHA) and the specificities ranged from 99.3% (IIF) to 80.2% (PHA). The sensitivity and specificity of the PHA and the sensitivity of the Karpas cell test were significantly lower than those of the other tests. Although the IFF and dot blot had good sensitivities and specificities, the six ELISA were more attractive than those tests when other parameters such as ease of reading and duration of assay were considered

Genetic and antigenic variability of HIV type 1 in Brazil

Submitted by Ana Maria Fiscina Sampaio ([email protected]) on 2016-07-15T16:40:15Z No. of bitstreams: 1 Fernandez JCC Genetic and antigenic....pdf: 1132381 bytes, checksum: 6370b2247fbe22dfd514a5b84c9a620f (MD5)Approved for entry into archive by Ana Maria Fiscina Sampaio ([email protected]) on 2016-07-15T16:53:26Z (GMT) No. of bitstreams: 1 Fernandez JCC Genetic and antigenic....pdf: 1132381 bytes, checksum: 6370b2247fbe22dfd514a5b84c9a620f (MD5)Made available in DSpace on 2016-07-15T16:53:26Z (GMT). No. of bitstreams: 1 Fernandez JCC Genetic and antigenic....pdf: 1132381 bytes, checksum: 6370b2247fbe22dfd514a5b84c9a620f (MD5) Previous issue date: 1994-09Fundação Gonçalo Moniz. Centro de Pesquisas Gonçalo Moniz. Laboratório Avançado de Saúde Pública. Salvador, BA, BrasilInstitute of Tropical Medicine. Division of Microbiology. Department of Infection and Immunity. Antwerp, BelgiumInstitute of Tropical Medicine. Division of Microbiology. Department of Infection and Immunity. Antwerp, BelgiumInstitute of Tropical Medicine. Division of Microbiology. Department of Infection and Immunity. Antwerp, BelgiumInstitute of Tropical Medicine. Division of Microbiology. Department of Infection and Immunity. Antwerp, BelgiumInstitute of Tropical Medicine. Division of Microbiology. Department of Infection and Immunity. Antwerp, BelgiumINSERM U13. IMEA-Hôpital Bichat-Claude Bernard. Paris, FranceFundação Gonçalo Moniz. Centro de Pesquisas Gonçalo Moniz. Laboratório Avançado de Saúde Pública. Salvador, BA, BrasilInstitute of Tropical Medicine. Division of Microbiology. Department of Infection and Immunity. Antwerp, BelgiumInstitute of Tropical Medicine. Division of Microbiology. Department of Infection and Immunity. Antwerp, BelgiumSix Brazilian strains of human immunodeficiency virus type 1 (HIV-1) were isolated from infected individuals residing in different regions of Brazil between 1987 and 1989. Phylogenetic analysis based on an 860-base pair env fragment, including V3, V4, V5, and the beginning of gp41, classified the Brazilian strains significantly in genotype B, with interhost distances between 5.9 and 13.1% (mean value, 10%). Amino acid sequence analysis of the V3 loop revealed that three strains contained the North American/European GPGR motif as the tip of the loop whereas in the other three strains proline (P) was substituted by tryptophan (W), methionine (M), or phenylalanine (F). A consensus peptide, Bra-cons, was designed containing GWGR as the tip of the loop. Serological reactivity to the Bra-cons peptide and other V3 peptides (MN, SF2, HBX2, RF, MAL, ELI, Z6, and a Côte d'Ivoire peptide, CI-cons) was compared for 114 HIV-1-positive sera from Rio de Janeiro. Sixty-nine sera (60.5%) reacted with peptides belonging to genotype B, of which 10 sera also reacted with peptides belonging to genotype A (n = 7) and D (n = 3). Eighteen sera (15.8%) had binding antibodies to the Bra-cons peptide. A high number of sera (n = 43; 37.7%) had no antibodies to any of the V3 peptides tested. This result suggests that HIV-1 variants with aberrant V3 loops may circulate in Rio de Janeiro

Soroprevalência do HIV, HTLV-I/II e outros patógenos de transmissão perinatal em Salvador, Bahia

Generation of epidemiological data on perinatally-transmitted infections is a fundamental tool for the formulation of health policies. In Brazil, this information is scarce, particularly in Northeast, the poorest region of the country. In order to gain some insights of the problem we studied the seroprevalence of some perinatally-transmitted infections in 1,024 low income pregnant women in Salvador, Bahia. The prevalences were as follow: HIV-1 (0.10%), HTLV-I/II (0.88%), T.cruzi (2.34%). T.pallidum (3.91%), rubella virus (77.44%). T.gondii IgM (2.87%) and IgG (69.34%), HBs Ag (0.6%) and anti-HBs (7.62%). Rubella virus and T.gondii IgG antibodies were present in more than two thirds of pregnant women but antibodies against other pathogens were present at much lower rates. We found that the prevalence of HTLV-I/II was nine times higher than that found for HIV-1. In some cases such as T.cruzi and hepatitis B infection there was a decrease in the prevalence over the years. On the other hand, there was an increase in the seroprevalence of T.gondii infection. Our data strongly recommend mandatory screening tests for HTLV-I/II, T.gondii (IgM), T.pallidum and rubella virus in prenatal routine for pregnant women in Salvador. Screening test for T.cruzi, hepatitis and HIV-1 is recommended whenever risk factors associated with these infections are suspected. However in areas with high prevalence for these infections, the mandatory screening test in prenatal care should be considered.A obtenção de dados epidemiológicos é de fundamental importância para o estabelecimento de políticas em Saúde Pública. No Brasil, essas informações são escassas, principalmente na região Nordeste. Para se obter alguns destes dados, avaliamos a soroprevalência de algumas infecções de transmissão perinatal, em cerca de 1024 gestantes de baixa renda, em Salvador, Bahia. Os resultados encontrados foram os seguintes: HIV-1 (0,10%), HTLV-I/II (0,88%), T.cruzi (2,34%), T.pallidum (3,91%), vírus da rubéola (77,44%), IgM e IgG para T.gondii (2,87% e 69,34%, respectivamente), e antígenos e anticorpos de superfície (HBs Ag e anti-HBs) do vírus da hepatite B (0,6% e 7,62%, respectivamente). A prevalência de HTLV-I/II foi nove vezes maior do que aquela observada para o HIV-1. Constatou-se um decréscimo na prevalência das infecções causadas pelos T.cruzi e o vírus da hepatite B, em relação a anos anteriores, enquanto na infecção pelo T.gondii houve um aumento. Em função dos dados encontrados recomendamos que em Salvador, testes de triagem para HTLV-I, IgM, para T.gondii, T.pallidum e o vírus da rubéola, sejam feitos como rotina prenatal, e que triagens para T.cruzi, hepatite B e HIV-1 sejam feitas quando estiverem presentes fatores de risco associados a estas infecções. Entretanto, em áreas com altas taxas de prevalência para estas infecções, a triagem no prenatal deve ser considerada

Bayesian MCMC test of phylogenetic isolation of Brazilian HIV-1 subtype C sequences by geographic region.

a<p>Expected AI or PS value under the null hypothesis of no phylogenetic clustering of isolates by sampling location. PA: Porto Alegre. FL: Florianópolis. CU: Curitiba.</p