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1.
PLoS One ; 14(10): e0223210, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31574109

RESUMO

BACKGROUND: Protease inhibitors (PI) are especially important in salvage therapy. Previous treatment failure with a PI containing regimen may elicit resistance mutations, reducing PI susceptibility and limiting treatment options. The aim of this study was to describe major PI mutations among patients exposed to at least one PI to evaluate predictors of mutation emergence and the impact of subtypes on resistance. METHODOLOGY: Partial HIV-1 pol sequences (Sanger Sequencing) from patients exposed to PI with virological failure were genotyped from January 2014 to December 2017. Drug resistance mutations (DRM), antiretroviral susceptibility (GSS) and subtypes, along clinical and laboratory parameters, were evaluated using logistic regression to access the predictors of mutation emergence. RESULTS: In 27.5% (466/1696) of the cases at least one major PI mutations was identified, most commonly M46 (14.7%), V82 (13.8%) and I54 (13.3%). Mutations to NRTI and NNRTI were observed in 69.6% and 59.9%, respectively, of the 1696 sequences. Full activity to darunavir was predicted in 88% (1496/1696), but was only 57% among those with at least one PI-DRM. Subtype C sequences had less major PI-DRMs (10%, 9/87) compared to B (28%, 338/1216) or F (35%, 58/168) (p <0.001) but adjusted analysis suggested that this association is not independent from a shorter treatment time and fewer regimens (OR 0.59, Confidence Interval 95: 0.2-2.5, p = 0.48). Subtype F, together with NRTI mutations and longer time on treatment was associated to presence of PI-DRM, to a lower darunavir GSS and to mutations at codon I50. CONCLUSIONS: Among patients with PI-DRM, full activity to darunavir was compromised in almost half of the cases and efforts to detect failure at earlier time are warranted, particularly for HIV-1 subtype F that showed association to the emergence of resistance, with potential impact in protease inhibitors sequencing. Furthermore, NRTI mutations may serve as an indicative of sufficient adherence to allow PI-DRM emergence.


Assuntos
Farmacorresistência Viral/genética , Infecções por HIV/tratamento farmacológico , HIV-1/genética , Inibidores de Proteases/uso terapêutico , Adulto , Fármacos Anti-HIV/uso terapêutico , Terapia Antirretroviral de Alta Atividade/efeitos adversos , Brasil/epidemiologia , Darunavir/uso terapêutico , Feminino , Genótipo , Infecções por HIV/epidemiologia , Infecções por HIV/genética , Infecções por HIV/virologia , Protease de HIV/genética , HIV-1/efeitos dos fármacos , HIV-1/patogenicidade , Humanos , Masculino , Pessoa de Meia-Idade , Mutação , Falha de Tratamento , Carga Viral/efeitos dos fármacos
2.
Mem. Inst. Oswaldo Cruz ; 113(1): 38-44, Jan. 2018. tab, graf
Artigo em Inglês | LILACS | ID: biblio-894888

RESUMO

BACKGROUND A number of Zika virus (ZIKV) sequences were obtained using Next-generation sequencing (NGS), a methodology widely applied in genetic diversity studies and virome discovery. However Sanger method is still a robust, affordable, rapid and specific tool to obtain valuable sequences. OBJECTIVE The aim of this study was to develop a simple and robust Sanger sequencing protocol targeting ZIKV relevant genetic regions, as envelope protein and nonstructural protein 5 (NS5). In addition, phylogenetic analysis of the ZIKV strains obtained using the present protocol and their comparison with previously published NGS sequences were also carried out. METHODS Six Vero cells isolates from serum and one urine sample were available to develop the procedure. Primer sets were designed in order to conduct a nested RT-PCR and a Sanger sequencing protocols. Bayesian analysis was used to infer phylogenetic relationships. FINDINGS Seven complete ZIKV envelope protein (1,571 kb) and six partial NS5 (0,798 Kb) were obtained using the protocol, with no amplification of NS5 gene from urine sample. Two NS5 sequences presented ambiguities at positions 495 and 196. Nucleotide analysis of a Sanger sequence and consensus sequence of previously NGS study revealed 100% identity. ZIKV strains described here clustered within the Asian lineage. MAIN CONCLUSIONS The present study provided a simple and low-cost Sanger protocol to sequence relevant genes of the ZIKV genome. The identity of Sanger generated sequences with published consensus NGS support the use of Sanger method for ZIKV population studies. The regions evaluated were able to provide robust phylogenetic signals and may be used to conduct molecular epidemiological studies and monitor viral evolution.


Assuntos
RNA Viral/genética , Genoma Viral/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Zika virus/genética , Filogenia , Proteínas não Estruturais Virais , Sequenciamento de Nucleotídeos em Larga Escala
3.
Mem Inst Oswaldo Cruz ; 113(1): 38-44, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29185594

RESUMO

BACKGROUND: A number of Zika virus (ZIKV) sequences were obtained using Next-generation sequencing (NGS), a methodology widely applied in genetic diversity studies and virome discovery. However Sanger method is still a robust, affordable, rapid and specific tool to obtain valuable sequences. OBJECTIVE: The aim of this study was to develop a simple and robust Sanger sequencing protocol targeting ZIKV relevant genetic regions, as envelope protein and nonstructural protein 5 (NS5). In addition, phylogenetic analysis of the ZIKV strains obtained using the present protocol and their comparison with previously published NGS sequences were also carried out. METHODS: Six Vero cells isolates from serum and one urine sample were available to develop the procedure. Primer sets were designed in order to conduct a nested RT-PCR and a Sanger sequencing protocols. Bayesian analysis was used to infer phylogenetic relationships. FINDINGS: Seven complete ZIKV envelope protein (1,571 kb) and six partial NS5 (0,798 Kb) were obtained using the protocol, with no amplification of NS5 gene from urine sample. Two NS5 sequences presented ambiguities at positions 495 and 196. Nucleotide analysis of a Sanger sequence and consensus sequence of previously NGS study revealed 100% identity. ZIKV strains described here clustered within the Asian lineage. MAIN CONCLUSIONS: The present study provided a simple and low-cost Sanger protocol to sequence relevant genes of the ZIKV genome. The identity of Sanger generated sequences with published consensus NGS support the use of Sanger method for ZIKV population studies. The regions evaluated were able to provide robust phylogenetic signals and may be used to conduct molecular epidemiological studies and monitor viral evolution.


Assuntos
Genoma Viral/genética , Sequenciamento de Nucleotídeos em Larga Escala , RNA Viral/genética , Proteínas não Estruturais Virais/genética , Zika virus/genética , Teorema de Bayes , Humanos , Filogenia , Reação em Cadeia da Polimerase Via Transcriptase Reversa
4.
AIDS Res Hum Retroviruses ; 31(12): 1219-24, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25826640

RESUMO

Transmitted drug resistance mutations (TDRM) have been a constant threat to treatment efficacy. We evaluated TDRM in plasma RNA of 217 antiretroviral therapy-naive patients from sites in the São Paulo metropolitan area, collected from 2012 to 2014. The partial HIV-1 polymerase region was sequenced using Big Dye terminators at an ABI 3130 Genetic Analyzer. TDRM was defined according to the Stanford database calibrated population resistance (CPR v.6.0), but other drug resistance mutations (DRM) considered at the IAS list (IAS, 2014) and at the Stanford HIV Database Genotyping Resistance Interpretation (GRI-HIVdb) were also described. Out of 78% (170/217) of patients with information on the time of diagnosis, most (83%, 141/170) had been recently diagnosed, with the first positive HIV serology at a median of 58 days (IQR 18-184). Subtype B predominated (70%), followed by subtype F (10%), BF (7.5%), C (7.5%), and BC (5%). TDRMs were observed in 9.2% (20/217, CI 95% 5.9% to 13.6%), mostly (5.2%) to nonnucleoside reverse transcriptase inhibitor (NNRTI) antiretroviral class. Among children and adolescents, only a single patient showed TDRMs. Additional non-CPR mutations were observed: 11.5% (25/217) according to IAS or 4.6% (10/217) according to GRI-HIVdb. Overall, 23.5% (51/217) of the cases had one or more DRM identified. TDRM prevalence differed significantly among some sites. These trends deserve continuous and systematic surveillance, especially with the new policies of treatment as prevention being implemented in the country.


Assuntos
Transmissão de Doença Infecciosa , Farmacorresistência Viral , Infecções por HIV/transmissão , Infecções por HIV/virologia , HIV-1/efeitos dos fármacos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Brasil , Criança , Pré-Escolar , Feminino , Genótipo , HIV-1/enzimologia , HIV-1/genética , HIV-1/isolamento & purificação , Humanos , Lactente , Recém-Nascido , Masculino , Pessoa de Meia-Idade , Análise de Sequência de DNA , Adulto Jovem , Produtos do Gene pol do Vírus da Imunodeficiência Humana/genética
5.
J Antimicrob Chemother ; 70(3): 926-9, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25386009

RESUMO

OBJECTIVES: Dolutegravir is a second-generation integrase strand transfer inhibitor (InSTI) that has been recently approved by the FDA to treat antiretroviral therapy-naive as well as treatment-experienced HIV-infected individuals, including those already exposed to the first-generation InSTI. Despite having a different mutational profile, some cross-resistance mutations may influence its susceptibility. The aim of this study was to evaluate the impact of a raltegravir-containing salvage regimen on dolutegravir activity. PATIENTS AND METHODS: Blood samples of 92 HIV-infected individuals with virological failure (two or more viral loads >50 copies/mL after 6 months of treatment) using raltegravir with optimized background therapy were sequenced and evaluated according to the Stanford University HIV Drug Resistance Database algorithm. RESULTS: Among the 92 patients analysed, 32 (35%) showed resistance to dolutegravir, in most cases associated with the combination of Q148H/R/K with G140S/A mutations. At genotyping, patients with resistance to dolutegravir had viral load values closer to the highest previously documented viral load. CONCLUSIONS: Changes in viraemia during virological failure may indicate the evolution of raltegravir resistance and may predict the emergence of secondary mutations that are associated with a decrease in dolutegravir susceptibility. Early discontinuation of raltegravir from failing regimens might favour subsequent salvage with dolutegravir, but further studies are necessary to evaluate this issue.


Assuntos
Fármacos Anti-HIV/farmacologia , Fármacos Anti-HIV/uso terapêutico , Farmacorresistência Viral , Infecções por HIV/tratamento farmacológico , HIV-1/efeitos dos fármacos , Compostos Heterocíclicos com 3 Anéis/farmacologia , Pirrolidinonas/uso terapêutico , Adulto , Feminino , Genótipo , HIV-1/classificação , HIV-1/genética , Humanos , Masculino , Pessoa de Meia-Idade , Mutação de Sentido Incorreto , Oxazinas , Piperazinas , Piridonas , Raltegravir Potássico , Terapia de Salvação/métodos , Análise de Sequência de DNA , Falha de Tratamento , Adulto Jovem
6.
Artigo em Inglês | LILACS, Sec. Est. Saúde SP, SESSP-IALPROD, Sec. Est. Saúde SP, SESSP-IALACERVO | ID: biblio-1021437

RESUMO

Transmitted drug resistance mutations (TDRM) have been a constant threat to treatment efficacy. We evaluated TDRM in plasma RNA of 217 antiretroviral therapy-naive patients from sites in the São Paulo metropolitan area, collected from 2012 to 2014. The partial HIV-1 polymerase region was sequenced using Big Dye terminators at an ABI 3130 Genetic Analyzer. TDRM was defined according to the Stanford database calibrated population resistance (CPR v.6.0), but other drug resistance mutations (DRM) considered at the IAS list (IAS, 2014) and at the Stanford HIV Database Genotyping Resistance Interpretation (GRI-HIVdb) were also described. Out of 78% (170/217) of patients with information on the time of diagnosis, most (83%, 141/170) had been recently diagnosed, with the first positive HIV serology at a median of 58 days (IQR 18-184). Subtype B predominated (70%), followed by subtype F (10%), BF (7.5%), C (7.5%), and BC (5%). TDRMs were observed in 9.2% (20/217, CI 95% 5.9% to 13.6%), mostly (5.2%) to nonnucleoside reverse transcriptase inhibitor (NNRTI) antiretroviral class. Among children and adolescents, only a single patient showed TDRMs. Additional non-CPR mutations were observed: 11.5% (25/217) according to IAS or 4.6% (10/217) according to GRI-HIVdb. Overall, 23.5% (51/217) of the cases had one or more DRM identified. TDRM prevalence differed significantly among some sites. These trends deserve continuous and systematic surveillance, especially with the new policies of treatment as prevention being implemented in the country.


Assuntos
Brasil , Humanos , Resistência a Medicamentos , Infecções por HIV , Criança , Pré-Escolar , Adolescente , HIV , Transmissão de Doença Infecciosa , Adulto , Produtos do Gene pol do Vírus da Imunodeficiência Humana , Genótipo
7.
Braz. j. infect. dis ; 18(3): 300-307, May-June/2014. tab, graf
Artigo em Inglês | LILACS, Sec. Est. Saúde SP | ID: lil-712953

RESUMO

Management of children with HIV/AIDS is specially challenging. Age-related issues do not allow for direct transposition of adult observations to this population. CXCR4 tropism has been associated with disease progression in adults. The geno2pheno web-base is a friendly tool to predict viral tropism on envelope V3 sequences, generating a false positive rate for a CXCR4 prediction. We evaluated the association of HIV-1 tropism prediction with clinical and laboratory outcome of 73 children with HIV/AIDS in São Paulo, Brazil. The CXCR4 tropism was strongly associated with a lower (nadir) CD4 documented during follow-up (p < 0.0001) and with disease severity (clinical event and/or CD4 below 200 cells/mm3) at the last observation, using commonly applied clinical cutoffs, such as10%FPRclonal (p = 0.001). When variables obtained during follow-up are included, both treatment adherence and viral tropism show a significant association with disease severity. As for viremia suppression, 30% (22/73) were undetectable at the last observation, with only adherence strongly associated with suppression after adjustment. The study brings further support to the notion that antiretroviral treatment adherence is pivotal to management of HIV disease, but suggests that tropism prediction may provide an additional prognostic marker to monitor HIV disease in children.


Assuntos
Adolescente , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Masculino , HIV-1 , Progressão da Doença , Infecções por HIV/virologia , /fisiologia , Tropismo Viral/fisiologia , Antirretrovirais/uso terapêutico , Genótipo , Infecções por HIV/tratamento farmacológico , Infecções por HIV/fisiopatologia , RNA Viral/sangue , Carga Viral
8.
AIDS Res Hum Retroviruses ; 30(7): 711-6, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24673579

RESUMO

HIV-1 tropism determination is necessary prior to CCR5 antagonist use as antiretroviral therapy. Genotypic prediction of coreceptor use is a practical alternative to phenotypic tests. Cell DNA and plasma RNA-based prediction has shown discordance in many studies. We evaluate paired cell and plasma either as single or replicate V3 sequences to assess prediction comparability. The HIV-1 partial env region was sequenced and tropism was predicted using geno2pheno and position-specific scoring matrices (PSSM). Nucleotide ambiguities at V3 were quantified and genetic distance (Protdist) was determined using BioEdit. Wilcoxon signed-rank test, t tests, and Spearman correlation were performed with Prism GraphPad5.0. Results are expressed as medians, with a level of significance of p<0.05, two tailed. Single (n=28) or replicate (n=26) paired cell/plasma sequences were obtained from 54 patients. Although the clonalfalse-positive rate (FPR) value from both compartments strongly correlated (r=0.86 p<0.0001), discordance in tropism prediction was observed in both singles and replicates using geno2pheno or PSSM. Applying clonalFPR(10%) 46% (25/54) were X4 tropic, with a plasma/cell discordance of 11% in singles and 23% in replicates. Genetic distance (p<0.0001) and clonalFPR value dispersion (p=0.003) were significantly higher among replicate sequences from cells. Discordance of viral tropism prediction is not uncommon and the use of replicates does not decrease its occurrence, but improves X4 sensitivity. Sequences from provirus had greater genetic distance and dispersion of clonalFPR values. This may suggest that DNA replicate assays may better represent the diversity of HIV-1 variants, but the clinical significance of these findings needs further evaluation.


Assuntos
HIV-1/fisiologia , Receptores CCR5/genética , Tropismo Viral/genética , Produtos do Gene env do Vírus da Imunodeficiência Humana/genética , Sequência de Bases , Antígenos CD4/metabolismo , Variação Genética , HIV-1/genética , Humanos , RNA Viral/genética , Receptores CCR5/metabolismo , Receptores CXCR4/genética , Receptores CXCR4/metabolismo , Análise de Sequência de RNA
9.
Braz J Infect Dis ; 18(3): 300-7, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24275366

RESUMO

Management of children with HIV/AIDS is specially challenging. Age-related issues do not allow for direct transposition of adult observations to this population. CXCR4 tropism has been associated with disease progression in adults. The geno2pheno web-base is a friendly tool to predict viral tropism on envelope V3 sequences, generating a false positive rate for a CXCR4 prediction. We evaluated the association of HIV-1 tropism prediction with clinical and laboratory outcome of 73 children with HIV/AIDS in São Paulo, Brazil. The CXCR4 tropism was strongly associated with a lower (nadir) CD4 documented during follow-up (p<0.0001) and with disease severity (clinical event and/or CD4 below 200cells/mm(3)) at the last observation, using commonly applied clinical cutoffs, such as (10%)FPRclonal (p=0.001). When variables obtained during follow-up are included, both treatment adherence and viral tropism show a significant association with disease severity. As for viremia suppression, 30% (22/73) were undetectable at the last observation, with only adherence strongly associated with suppression after adjustment. The study brings further support to the notion that antiretroviral treatment adherence is pivotal to management of HIV disease, but suggests that tropism prediction may provide an additional prognostic marker to monitor HIV disease in children.


Assuntos
Progressão da Doença , Infecções por HIV/virologia , HIV-1/fisiologia , Receptores CXCR4/fisiologia , Tropismo Viral/fisiologia , Adolescente , Antirretrovirais/uso terapêutico , Contagem de Linfócito CD4 , Criança , Pré-Escolar , Feminino , Genótipo , Infecções por HIV/tratamento farmacológico , Infecções por HIV/fisiopatologia , Humanos , Lactente , Masculino , RNA Viral/sangue , Carga Viral
10.
Rev Inst Med Trop Sao Paulo ; 54(4): 207-13, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22850992

RESUMO

The objective of this study is to identify subtypes of Human Immunodeficiency Virus type 1 (HIV-1) and to analyze the presence of mutations associated to antiretroviral resistance in the protease (PR) and reverse transcriptase (RT) regions from 48 HIV-1 positive treatment naïve patients from an outpatient clinic in Maringá, Paraná, Brazil. Sequencing was conducted using PR, partial RT and group-specific antigen gene (gag) nested PCR products from retrotranscribed RNA. Transmitted resistance was determined according to the Surveillance Drug Resistance Mutation List (SDRM) algorithm. Phylogenetic and SimPlot analysis of concatenated genetic segments classified sequences as subtype B 19/48 (39.6%), subtype C 12/48 (25%), subtype F 4/48 (8.3%), with 13/48 (27.1%) recombinant forms. Most recombinant forms were B mosaics (B/F 12.5%, B/C 10.4%), with one C/F (2.1%) and one complex B/C/F mosaic (2.1%). Low levels of transmitted resistance were found in this study, 2/48 (2.1% to NRTIs and 2.1% for PI). This preliminary data may subsidize the monitoring of the HIV evolution in the region.


Assuntos
Farmacorresistência Viral/genética , Infecções por HIV/virologia , Protease de HIV/genética , Transcriptase Reversa do HIV/genética , HIV-1/genética , Mutação/genética , Adolescente , Adulto , Sequência de Bases , Relação CD4-CD8 , Feminino , Genótipo , HIV-1/efeitos dos fármacos , Humanos , Masculino , Pessoa de Meia-Idade , Dados de Sequência Molecular , Filogenia , Adulto Jovem
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