Short communication: phylodynamics analysis of the human immunodeficiency virus type 1 envelope gene in mother and child pairs.

Characterizing the impact of HIV transmission routes on viral genetic diversity can improve the understanding of the mechanisms of virus evolution and adaptation. HIV vertical transmission can occur in utero, during delivery, or while breastfeeding. The present study investigated the phylodynamics of the HIV-1 env gene in mother-to-child transmission by analyzing one chronically infected pair from Brazil and three acutely infected pairs from Zambia, with three to five time points. Sequences from 25 clones from each sample were obtained and aligned using Clustal X. ML trees were constructed in PhyML using the best evolutionary model. Bayesian analyses testing the relaxed and strict molecular clock were performed using BEAST and a Bayesian Skyline Plot (BSP) was construed. The genetic variability of previously described epitopes was investigated and compared between each individual time point and between mother and child sequences. The relaxed molecular clock was the best-fitted model for all datasets. The tree topologies did not show differentiation in the evolutionary dynamics of the virus circulating in the mother from the viral population in the child. In the BSP, the effective population size was more constant in time in the chronically infected patients while in the acute patients it was possible to detect bottlenecks. The genetic variability within viral epitopes recognized by the human immune system was considerably higher among the chronically infected pair in comparison with acutely infected pairs. These results contribute to a better understanding of HIV-1 evolutionary dynamics in mother-to-child transmission.

Amino- and Carboxyl-Terminal CCR5 Mutations in Brazilian HIV-1-Infected Women and Homology Model of p.L55Q CCR5 Mutant.

Genetic factors from an HIV-1 host can affect the rate of progression to AIDS and HIV infection. To investigate the frequency of mutations in the CCR5 gene, HIV-1 samples from infected women and uninfected individuals were selected for sequencing of the CCR5 gene regions encoding the N- and C-terminal protein domains. Physicochemical CCR5 modeling and potential protein domain analysis were performed in order to evaluate the impact of the mutations found in the properties and structure of CCR5. The p.L55Q mutation in the N-terminal protein domain was observed only in uninfected individuals, with an allelic frequency of 1.8%. Physicochemical analysis revealed that the p.L55Q mutation magnified the flexibility and accessibility profiles and the modeling of CCR5 structures showed resulting in a small deviation to the right, as well as a hydrophobic to hydrophilic property alteration. The p.L55Q mutation also resulted in a slight modification of the electrostatic load of this region. Additionally, three novel silent mutations were found at the C-terminal coding region among HIV-1-infected women. The results suggest that the p.L55Q mutation might alter CCR5 conformation. Further studies should be conducted to verify the role of this mutation in HIV-1 susceptibility.

Diversidade genética do vírus da imunodeficiência humana tipo 1 (HIV-1) em mulheres infectadas de uma cidade do nordeste do Brasil / Genetic diversity of human immunodeficiency virus type-1 (HIV-1) in infected women from a northeast city of Brazil

OBJETIVO: descrever a diversidade genética dos isolados de HIV-1 de mulheres soropositivas acompanhadas em um centro de referência. MÉTODOS: estudo transversal, no qual foram incluídas 96 mulheres com dois testes sorológicos ELISA e um teste confirmatório Western Blot. Das amostras de sangue periférico, foram determinadas a carga viral pelo kit b-DNA e a contagem de linfócitos T CD4 e T CD8 pela citometria de fluxo excalibur. A extração e purificação do DNA pró-viral foi realizada pela reação em cadeia da polimerase (PCR), utilizando o kit QIAamp Blood (Qiagen Inc., Chatsworth, CA, USA). O sequenciamento da região pol foi realizado em 52 isolados com o (3100 Genetic Analyzer, Applied Biosystems Inc., Foster City, CA) e a genotipagem foi investigada pela ferramenta Rega (Rega Subtyping Tool). O padrão de resistência aos antirretrovirais (ARV) foi inferido pelo algoritmo do banco de dados Stanford HIV Resistance. Os estágios clínicos das participantes foram definidos como A, B ou C segundo os critérios do Center for Diseases Control (CDC). Para a análise estatística dos dados, foram utilizados os testes do χ2 para as variáveis categóricas e o teste t de Student para as variáveis numéricas. RESULTADOS: a média de idade da amostra, o tempo médio de doença e de tratamento foram: 33,7; 3,8 e 2,5 anos, respectivamente. A média da carga viral foi log10 2,3 cópias/mL; a dos linfócitos T CD4 e T CD8 foi 494,9 células/µL e 1126,4 células/µL. Sobre o estágio clínico, 30 mulheres estavam no estádio A, 47 no B e 19 no C. O sequenciamento dos 52 isolados encontrou 33 do subtipo B, quatro do F, um do C e 14 do recombinante BF. A análise da resistência aos ARV mostrou 39 (75,0 por cento) isolados susceptíveis, 13 (25,0 por cento) resistentes aos inibidores da transcriptase reversa (INTR) e três (5,7 por cento) aos inibidores da protease (IP). CONCLUSÕES: Houve grande diversidade do HIV-1 e elevado percentual de isolados resistentes aos ARV na amostra estudada.

PURPOSE: to describe the genetic diversity of HIV-1 isolates from serum positive women followed up at a reference center. METHODS: transversal study, including 96 women with two ELISA serological tests and a Western Blot confirmatory test. The viral charge was determined by the b-DNA kit, and the counting of T CD4 and T CD8 lymphocytes, by the Excalibur flow cytometry, from the samples of peripheral blood. The extraction and purification of pro-viral DNA was performed by the polymerase (PCR) chain reaction, using the QIAamp Blood kit (Qiagen Inc., Chatsworth, CA, U.S.A.). Sequencing of the pol region was done in 52 isolates with the 3100 Genetic Analyzer (Applied Biosystems Inc., Foster City, CA), and the genotyping was assessed by the Rega Subtyping Tool. The resistance pattern to anti-retrovirals (ARV) was inferred by the algorithm from the Stanford HIV Resistance data bank. Participants' clinical stages were defined as A, B or C, according to the criteria established by the Center for Diseases Control (CDC). For statistical analysis, the χ2 test was used for the categorical variables and the Student's t test, for the numerical variables. RESULTS: The average age of the sample, the disease and treatment average duration were respectively: 33.7 years old, 3.8 and 2.5 years. The viral charge average was log10 2.3 copies/mL; the T CD4 e T CD8 lymphocytes, 494.9 cells/µL and 1126.4 cells/µL. Concerning the clinical stage, 30 women were in stage A, 47 in B and 19 in C. Sequencing from the 52 isolates found 33 of B subtype, 4 of F, 1 of C and 14 of BF recombinant. The analysis of resistance to ARV has shown 39 (75.0 percent) susceptible isolates, 13 (25.0 percent) resistant to reversal transcriptase inhibitors (RTIN), and 3 (5.7 percent) resistant to protease inhibitor (PI). CONCLUSIONS: There has been a large variety of HIV-1 and a high percentage of isolates resistant to ARV in the studied sample.

[Genetic diversity of human immunodeficiency virus type-1 (HIV-1) in infected women from a northeast city of Brazil]. / Diversidade genética do vírus da imunodeficiência humana tipo 1 (HIV-1) em mulheres infectadas de uma cidade do nordeste do Brasil.

PURPOSE: to describe the genetic diversity of HIV-1 isolates from serum positive women followed up at a reference center. METHODS: transversal study, including 96 women with two ELISA serological tests and a Western Blot confirmatory test. The viral charge was determined by the b-DNA kit, and the counting of T CD4 and T CD8 lymphocytes, by the Excalibur flow cytometry, from the samples of peripheral blood. The extraction and purification of pro-viral DNA was performed by the polymerase (PCR) chain reaction, using the QIAamp Blood kit (Qiagen Inc., Chatsworth, CA, U.S.A.). Sequencing of the pol region was done in 52 isolates with the 3100 Genetic Analyzer (Applied Biosystems Inc., Foster City, CA), and the genotyping was assessed by the Rega Subtyping Tool. The resistance pattern to anti-retrovirals (ARV) was inferred by the algorithm from the Stanford HIV Resistance data bank. Participants' clinical stages were defined as A, B or C, according to the criteria established by the Center for Diseases Control (CDC). For statistical analysis, the chi(2) test was used for the categorical variables and the Student's t test, for the numerical variables. RESULTS: The average age of the sample, the disease and treatment average duration were respectively: 33.7 years old, 3.8 and 2.5 years. The viral charge average was log(10) 2.3 copies/mL; the T CD4 e T CD8 lymphocytes, 494.9 cells/microL and 1126.4 cells/microL. Concerning the clinical stage, 30 women were in stage A, 47 in B and 19 in C. Sequencing from the 52 isolates found 33 of B subtype, 4 of F, 1 of C and 14 of BF recombinant. The analysis of resistance to ARV has shown 39 (75.0%) susceptible isolates, 13 (25.0%) resistant to reversal transcriptase inhibitors (RTIN), and 3 (5.7%) resistant to protease inhibitor (PI). CONCLUSIONS: There has been a large variety of HIV-1 and a high percentage of isolates resistant to ARV in the studied sample.