Dynamics of HIV latency and reactivation in a primary CD4+ T cell model.

HIV latency is a major obstacle to curing infection. Current strategies to eradicate HIV aim at increasing transcription of the latent provirus. In the present study we observed that latently infected CD4+ T cells from HIV-infected individuals failed to produce viral particles upon ex vivo exposure to SAHA (vorinostat), despite effective inhibition of histone deacetylases. To identify steps that were not susceptible to the action of SAHA or other latency reverting agents, we used a primary CD4+ T cell model, joint host and viral RNA sequencing, and a viral-encoded reporter. This model served to investigate the characteristics of latently infected cells, the dynamics of HIV latency, and the process of reactivation induced by various stimuli. During latency, we observed persistence of viral transcripts but only limited viral translation. Similarly, the reactivating agents SAHA and disulfiram successfully increased viral transcription, but failed to effectively enhance viral translation, mirroring the ex vivo data. This study highlights the importance of post-transcriptional blocks as one mechanism leading to HIV latency that needs to be relieved in order to purge the viral reservoir.

Analysis of HIV-1 Vpr determinants responsible for cell growth arrest in Saccharomyces cerevisiae

Affiliation: Département de microbiologie et immunologie, Faculté de médecine, Université de Montréal

Análisis fármaco económico de dos tratamientos para pacientes vih positivos con carga viral indetectable

Los tratamientos para aumentar los niveles de cúmulo de diferenciación 4 – CD4 en personas que padecen la enfermedad ocasionada por el Virus de la Inmunodeficiencia Humana (VIH), son importantes tanto para el mejoramiento del bienestar de los pacientes, como para el buen funcionamiento de las instituciones de salud. La presente investigación compara la intervención farmacológica de dos líneas de tratamiento, Lamivudina, Zidovudina, Efavirenz contra Efavirenz, Emtricitabina, Disoproxilo de Tenofovir que se encuentran en la recomendación de esquema de primera línea según la Guía Práctica Clínica (2014). Se evaluó el efecto costo-efectivo de estos dos tratamientos basado en el aumento de los niveles de CD4 a lo largo de tres tiempos diferentes (inicial, 6 y 12 meses) y los costos de los medicamentos de acuerdo a los precios en Colombia según el SISMED en el año 2014. Se realizó un análisis de varianza factorial con medidas repetidas, un árbol de decisiones y un análisis de costo-efectividad incremental (ACEI). Se obtuvo información de 546 pacientes, tanto hombres como mujeres, de la Institución Asistencia Científica de Alta Complejidad S.A.S de la ciudad de Bogotá. Se encontró que el esquema 1 (Lamivudina, Zidovudina, Efavirenz) fue considerado más efectivo y menos costoso que el tratamiento 2 (Efavirenz, Emtricitabina, Disoproxilo de Tenofovir), sin embargo no se evidenció una alta frecuencia de efectos adversos que pueda contribuir a la escogencia de un tratamiento u otro. De acuerdo a estos resultados la institución o los médicos tratantes tienen una alternativa farmacoeconómica para la toma de decisión del tratamiento a utilizar y así iniciar la terapia antirretroviral de pacientes que conviven con VHI con carga viral indetectable.

Análisis fármaco económico de dos tratamientos para pacientes VIH positivos con carga viral indetectable

Los tratamientos para aumentar los niveles de cúmulo de diferenciación 4 – CD4 en personas que padecen la enfermedad ocasionada por el Virus de la Inmunodeficiencia Humana (VIH), son importantes tanto para el mejoramiento del bienestar de los pacientes, como para el buen funcionamiento de las instituciones de salud. La presente investigación compara la intervención farmacológica de dos líneas de tratamiento, Lamivudina, Zidovudina, Efavirenz contra Efavirenz, Emtricitabina, Disoproxilo de Tenofovir que se encuentran en la recomendación de esquema de primera línea según la Guía Práctica Clínica (2014). Se evaluó el efecto costo-efectivo de estos dos tratamientos basado en el aumento de los niveles de CD4 a lo largo de tres tiempos diferentes (inicial, 6 y 12 meses) y los costos de los medicamentos de acuerdo a los precios en Colombia según el SISMED en el año 2014. Se realizó un análisis de varianza factorial con medidas repetidas, un árbol de decisiones y un análisis de costo-efectividad incremental (ACEI). Se obtuvo información de 546 pacientes, tanto hombres como mujeres, de la Institución Asistencia Científica de Alta Complejidad S.A.S de la ciudad de Bogotá. Se encontró que el esquema 1 (Lamivudina, Zidovudina, Efavirenz) fue considerado más efectivo y menos costoso que el tratamiento 2 (Efavirenz, Emtricitabina, Disoproxilo de Tenofovir), sin embargo no se evidenció una alta frecuencia de efectos adversos que pueda contribuir a la escogencia de un tratamiento u otro. De acuerdo a estos resultados la institución o los médicos tratantes tienen una alternativa farmacoeconómica para la toma de decisión del tratamiento a utilizar y así iniciar la terapia antirretroviral de pacientes que conviven con VHI con carga viral indetectable.

Disease progression in heterosexual patients infected with closely related subtype B strains of HIV type 1 with differing coreceptor usage properties

Previously we described a heterosexual outbreak of HIV-1 subtype B in a town in the north of England (Doncaster) where 11 of 13 infections were shown to be linked by phylogenetic analysis of the env gp120 region. The 11 infections were related to a putative index case, Don1, and further divided into two groups based on the patients' disease status, their viral sequences, and other epidemiological information. Here we describe two further findings. First, we found that viral isolates and gp120 recombinant viruses derived from patients from one group used the CCR5 coreceptor, whereas viruses from the other group could use both the CCR5 and CXCR4 coreceptors. Patients with the X4/R5 dual tropic strains were symptomatic when diagnosed and progressed rapidly, in contrast to the other patient group that has remained asymptomatic, implying a link between the tropism of the strains and disease outcome. Second, we present additional sequence data derived from the index case, demonstrating the presence of sequences from both clades, with an average interclade distance of 9.56%, providing direct evidence of a genetic link between these two groups. This new study shows that Don1 harbored both strains, implying he was either dually infected or that over time intrahost diversification from the R5 to R5/X4 phenotype occurred. These events may account for/have led to the spread of two genetically related strains with different pathogenic properties within the same heterosexual community.

Coxsackievirus B3-associated myocardial pathology and viral load reduced by recombinant soluble human decay-accelerating factor in mice

Coxsackievirus B3 (CVB3) infection can result in myocarditis, which in turn may lead to a protracted immune response and subsequent dilated cardiomyopathy. Human decay-accelerating factor (DAF), a binding receptor for CVB3, was synthesized as a soluble IgG1-Fc fusion protein (DAF-Fc). In vitro, DAF-Fc was able to inhibit complement activity and block infection by CVB3, although blockade of infection varied widely among strains of CVB3. To determine the effects of DAF-Fc in vivo, 40 adolescent A/J mice were infected with a myopathic strain of CVB3 and given DAF-Fc treatment 3 days before infection, during infection, or 3 days after infection; the mice were compared with virus alone and sham-infected animals. Sections of heart, spleen, kidney, pancreas, and liver were stained with hematoxylin and eosin and submitted to in situ hybridization for both positive-strand and negative-strand viral RNA to determine the extent of myocarditis and viral infection, respectively. Salient histopathologic features, including myocardial lesion area, cell death, calcification and inflammatory cell infiltration, pancreatitis, and hepatitis were scored without knowledge of the experimental groups. DAF-Fc treatment of mice either preceding or concurrent with CVB3 infection resulted in a significant decrease in myocardial lesion area and cell death and a reduction in the presence of viral RNA. All DAF-Fc treatment groups had reduced infectious CVB3 recoverable from the heart after infection. DAF-Fc may be a novel therapeutic agent for active myocarditis and acute dilated cardiomyopathy if given early in the infectious period, although more studies are needed to determine its mechanism and efficacy.

Influence of hepatitis G virus (GB virus C) on the prognosis of HIV-infected women

This study was undertaken to evaluate the prevalence of GB virus C (GBV-C) viraemia and anti-E2 antibody, and to assess the effect of co-infection with GBV-C and HIV during a 10-year follow-up of a cohort of 248 HIV-infected women. Laboratory variables (mean and median CD4 counts, and HIV and GBV-C viral loads) and clinical parameters were investigated. At baseline, 115 women had past exposure to GBV-C: 57 (23%) were GBV-C RNA positive and 58 (23%) were anti-E2 positive. There was no statistical difference between the groups (GBV-C RNA + /anti-E2 -, GBV-C RNA - /anti-E2 + and GBV-C RNA - /anti-E2 -) regarding baseline CD4 counts or HIV viral loads (P = 0.360 and 0.713, respectively). Relative risk of death for the GBV-C RNA + /anti-E2 - group was 63% lower than that for the GBV-C RNA - /anti-E2 - group. Multivariate analysis demonstrated that only HIV loads >= 100,000 copies/mL and AIDS-defining illness during follow-up were associated with shorter survival after AIDS development. It is likely that antiretroviral therapy (ART) use in our cohort blurred a putative protective effect related to the presence of GBV-C RNA.

Tempol ameliorates murine viral encephalomyelitis by preserving the blood-brain barrier, reducing viral load, and lessening inflammation

Multiple sclerosis (MS) is a progressive inflammatory and/or demyelinating disease of the human central nervous system (CNS). Most of the knowledge about the pathogenesis of MS has been derived from murine models, such as experimental autoimmune encephalomyelitis and vital encephalomyelitis. Here, we infected female C57BL/6 mice with a neurotropic strain of the mouse hepatitis virus (MHV-59A) to evaluate whether treatment with the multifunctional antioxidant tempol (4-hydroxy-2,2,6,6-tetramethyl-1-piperidinyloxy) affects the ensuing encephalomyelitis. In untreated animals, neurological symptoms developed quickly: 90% of infected mice died 10 days after virus inoculation and the few survivors presented neurological deficits. Treatment with tempol (24 mg/kg, ip, two doses on the first day and daily doses for 7 days plus 2 mM tempol in the drinking water ad libitum) profoundly altered the disease outcome: neurological symptoms were attenuated, mouse survival increased up to 70%, and half of the survivors behaved as normal mice. Not Surprisingly, tempol substantially preserved the integrity of the CNS, including the blood-brain barrier. Furthermore, treatment with tempol decreased CNS vital titers, macrophage and T lymphocyte infiltration, and levels of markers of inflammation, such as expression of inducible nitric oxide synthase, transcription of tumor necrosis factor-alpha and interferon-gamma, and protein nitration. The results indicate that tempol ameliorates murine viral encephalomyelitis by altering the redox status of the infectious environment that contributes to an attenuated CNS inflammatory response. overall, our study supports the development of therapeutic strategies based on nitroxides to manage neuroinflammatory diseases, including MS. (C) 2009 Elsevier Inc. All rights reserved.

Análise quantitativa das células CD4 e sua importância no diagnóstico de lesões orais em pacientes HIV positivos

The oral manifestations due to HIV infection are, a lot of times, the first clinical signs of the disease. These injuries may also function as beepers and sentries of the curse and progression of the HIV infection and AIDS. The objective of this work was to evaluate the prevalence of the oral injuries in HIV positive patients, relating them with the CD4+ cells counting and the viral load in patients from the Hospital of Infected contagious Gizelda Trigueiro in Natal-RN. One hundred and one patients were evaluated, where after the clinical exam of the oral cavity, these ones were conducted to the peripheral blood collection for the counting of CD4+ lymphocytes. We observed a prevalence of 25,6%, that is, 31 cases. The Oral Candidiasis was the most commum injure, followed by Oral Hairy Leukoplakia, linear gingival erytema, lips herpes, gingivitis and periodontitis - HIV. The average counting of cells CD4+ of the injury carrying patients was of 250 cells/mm3. We did not observe relation between the presence of injuries and the viral load of the individuals

Intensified peginterferon α-2a dosing increases sustained virologic response rates in heavy, high viral load hepatitis c genotype 1 patients with high low-density lipoprotein

BACKGROUND AND GOAL: Patients infected with hepatitis C virus (HCV) with elevated low-density lipoprotein (LDL) levels achieve higher sustained virologic response (SVR) rates after peginterferon (PegIFN)/ribavirin treatment versus patients with lower LDL. Our aim was to determine whether SVR rates in patients with low/elevated LDL can be improved by dose intensification. STUDY: In PROGRESS, genotype 1 patients with baseline HCV RNA≥400,000 IU/mL and body weight ≥85 kg were randomized to 48 weeks of 180 μg/wk PegIFN α-2a (40 kDa) plus ribavirin (A: 1200 mg/d; B: 1400/1600 mg/d) or 12 weeks of 360 μg/wk PegIFN α-2a followed by 36 weeks of 180 μg/wk, plus ribavirin (C: 1200 mg/d; D: 1400/1600 mg/d). This retrospective analysis assessed SVR rates among patients with low (<100 mg/dL) or elevated (≥100 mg/dL) LDL. Patients with high LDL (n=256) had higher baseline HCV RNA (5.86×10 IU/mL) versus patients with low LDL (n=262; 4.02×10 IU/mL; P=0.0003). RESULTS: Multiple logistic regression analysis identified a significant interaction between PegIFN α-2a dose and LDL levels on SVR (P=0.0193). The only treatment-related SVR predictor in the nested multiple logistic regression was PegIFN α-2a dose among patients with elevated LDL (P=0.0074); therefore, data from the standard (A+B) and induction (C+D) dose arms were pooled. Among patients with low LDL, SVR rates were 40% and 35% in the standard and induction-dose groups, respectively; SVR rates in patients with high LDL were 44% and 60% (P=0.014), respectively. CONCLUSIONS: Intensified dosing of PegIFN α-2a increases SVR rates in patients with elevated LDL even with the difficult-to-cure characteristics of genotype 1, high baseline viral load, and high body weight. Copyright © 2013 by Lippincott Williams & Wilkins.

Characterization of polymorphisms in the mannose-binding lectin gene promoter among human immunodeficiency virus 1 infected subjects

ABSTRACT: The present study investigated the prevalence of mutations in the -550 (H/L) and -221 (X/Y) mannose-binding lectin (MBL) gene promoter regions and their impact on infection by human immunodeficiency virus 1 (HIV-1) in a population of 128 HIV-1 seropositive and 97 seronegative patients. The allele identification was performed through the sequence-specific primer polymerase chain reaction method, using primer sequences specific to each polymorphism. The evolution of the infection was evaluated through CD4+ T-lymphocyte counts and plasma viral load. The allele and haplotype frequencies among HIV-1-infected patients and seronegative healthy control patients did not show significant differences. CD4+ T-lymphocyte counts showed lower levels among seropositive patients carrying haplotypes LY, LX and HX, as compared to those carrying the HY haplotype. Mean plasma viral load was higher among seropositive patients with haplotypes LY, LX and HX than among those carrying the HY haplotype. When promoter and exon 1 mutations were matched, it was possible to identify a significantly higher viral load among HIV-1 infected individuals carrying haplotypes correlated to low serum levels of MBL. The current study shows that haplotypes related to medium and low MBL serum levels might directly influence the evolution of viral progression in patients. Therefore, it is suggested that the identification of haplotypes within the promoter region of the MBL gene among HIV-1 infected persons should be further evaluated as a prognostic tool for AIDS progression.

Avaliação do perfi de mutações e resistência aos inibidores de transcriptase reversa e protease em variantes HIV presentes em pacientes coinfectados pleo VHC

Pós-graduação em Pesquisa e Desenvolvimento (Biotecnologia Médica) - FMB

Genital infections of HIV-infected women assisted by a specialized service

The present study aimed at analyzing the persistence/recurrence of genital infections and its associated factors in HIV-infected women. Fifty-eight women treated for chlamydial infection, trichomoniasis, vulvovaginal candidiasis, and/or bacterial vaginosis (BV) and who had specimens collected for cure control up to one year after treatment were studied. Diagnoses were performed by the Gram staining method for cases of BV and candidiasis and by T. vaginalis culture and qualitative PCR for C. trachomatis. Antiretroviral therapy was used by 79.3% of patients, and 62.1% showed an undetectable HIV plasma load. The most frequent infection was BV with persistence/recurrence of 52.4%, which was associated with a longer time period between treatment and cure control (P = 0.0455), postmenopausal period (P = 0.0451), and having a steady partner (P = 0.007). Persistence/recurrence of vulvovaginal candidiasis was observed in 25%, trichomoniasis in 23.1%, and chlamydial infection in 10.5%. The letter was associated with inadequate treatment of the partner (P = 0.073) among patients with low T CD4 lymphocyte counts. The majority of women in the present study showed good HIV-infection control and a vulnerable sexual behavior, which stress the importance of maintaining gynecological followup.

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 Parana). 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, Florianopolis 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 (Parana state). This analysis further suggested that Florianopolis (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 (r(2) = 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.

Human TOP1 residues implicated in species specificity of HIV-1 infection are required for interaction with BTBD2, and RNAi of BTBD2 in old world monkey and human cells increases permissiveness to HIV-1 infection

Host determinants of HIV-1 viral tropism include factors from producer cells that affect the efficiency of productive infection and factors in target cells that block infection after viral entry. TRIM5 restricts HIV-1 infection at an early post-entry step through a mechanism associated with rapid disassembly of the retroviral capsid. Topoisomerase I (TOP1) appears to play a role in HIV-1 viral tropism by incorporating into or otherwise modulating virions affecting the efficiency of a post-entry step, as the expression of human TOP1 in African Green Monkey (AGM) virion-producing cells increased the infectivity of progeny virions by five-fold. This infectivity enhancement required human TOP1 residues 236 and 237 as their replacement with the AGM counterpart residues abolished the infectivity enhancement. Our previous studies showed that TOP1 interacts with BTBD1 and BTBD2, two proteins which co-localize with the TRIM5 splice variant TRIM5 in cytoplasmic bodies. Because BTBD1 and BTBD2 interact with one HIV-1 viral tropism factor, TOP1, and co-localize with a splice variant of another, we investigated the potential involvement of BTBD1 and BTBD2 in HIV-1 restriction.