Self-reported nonadherence to antiretroviral therapy as a predictor of viral failure and mortality

OBJECTIVE: To determine the effect of nonadherence to antiretroviral therapy (ART) on virologic failure and mortality in naive individuals starting ART. DESIGN: Prospective observational cohort study. METHODS: Eligible individuals enrolled in the Swiss HIV Cohort Study, started ART between 2003 and 2012, and provided adherence data on at least one biannual clinical visit. Adherence was defined as missed doses (none, one, two, or more than two) and percentage adherence (>95, 90-95, and <90) in the previous 4 weeks. Inverse probability weighting of marginal structural models was used to estimate the effect of nonadherence on viral failure (HIV-1 viral load >500 copies/ml) and mortality. RESULTS: Of 3150 individuals followed for a median 4.7 years, 480 (15.2%) experienced viral failure and 104 (3.3%) died, 1155 (36.6%) reported missing one dose, 414 (13.1%) two doses and, 333 (10.6%) more than two doses of ART. The risk of viral failure increased with each missed dose (one dose: hazard ratio [HR] 1.15, 95% confidence interval 0.79-1.67; two doses: 2.15, 1.31-3.53; more than two doses: 5.21, 2.96-9.18). The risk of death increased with more than two missed doses (HR 4.87, 2.21-10.73). Missing one to two doses of ART increased the risk of viral failure in those starting once-daily (HR 1.67, 1.11-2.50) compared with those starting twice-daily regimens (HR 0.99, 0.64-1.54, interaction P = 0.09). Consistent results were found for percentage adherence. CONCLUSION: Self-report of two or more missed doses of ART is associated with an increased risk of both viral failure and death. A simple adherence question helps identify patients at risk for negative clinical outcomes and offers opportunities for intervention.

The Depsipeptide Romidepsin Reverses HIV-1 Latency In Vivo.

UNLABELLED: Pharmacologically-induced activation of replication competent proviruses from latency in the presence of antiretroviral treatment (ART) has been proposed as a step towards curing HIV-1 infection. However, until now, approaches to reverse HIV-1 latency in humans have yielded mixed results. Here, we report a proof-of-concept phase Ib/IIa trial where 6 aviremic HIV-1 infected adults received intravenous 5 mg/m2 romidepsin (Celgene) once weekly for 3 weeks while maintaining ART. Lymphocyte histone H3 acetylation, a cellular measure of the pharmacodynamic response to romidepsin, increased rapidly (maximum fold range: 3.7-7.7 relative to baseline) within the first hours following each romidepsin administration. Concurrently, HIV-1 transcription quantified as copies of cell-associated un-spliced HIV-1 RNA increased significantly from baseline during treatment (range of fold-increase: 2.4-5.0; p = 0.03). Plasma HIV-1 RNA increased from <20 copies/mL at baseline to readily quantifiable levels at multiple post-infusion time-points in 5 of 6 patients (range 46-103 copies/mL following the second infusion, p = 0.04). Importantly, romidepsin did not decrease the number of HIV-specific T cells or inhibit T cell cytokine production. Adverse events (all grade 1-2) were consistent with the known side effects of romidepsin. In conclusion, romidepsin safely induced HIV-1 transcription resulting in plasma HIV-1 RNA that was readily detected with standard commercial assays demonstrating that significant reversal of HIV-1 latency in vivo is possible without blunting T cell-mediated immune responses. These finding have major implications for future trials aiming to eradicate the HIV-1 reservoir. TRIAL REGISTRATION: clinicaltrials.gov NTC02092116.

Reversible Reprogramming of Circulating Memory T Follicular Helper Cell Function during Chronic HIV Infection.

Despite the overwhelming benefits of antiretroviral therapy (ART) in curtailing viral load in HIV-infected individuals, ART does not fully restore cellular and humoral immunity. HIV-infected individuals under ART show reduced responses to vaccination and infections and are unable to mount an effective antiviral immune response upon ART cessation. Many factors contribute to these defects, including persistent inflammation, especially in lymphoid tissues, where T follicular helper (Tfh) cells instruct and help B cells launch an effective humoral immune response. In this study we investigated the phenotype and function of circulating memory Tfh cells as a surrogate of Tfh cells in lymph nodes and found significant impairment of this cell population in chronically HIV-infected individuals, leading to reduced B cell responses. We further show that these aberrant memory Tfh cells exhibit an IL-2-responsive gene signature and are more polarized toward a Th1 phenotype. Treatment of functional memory Tfh cells with IL-2 was able to recapitulate the detrimental reprogramming. Importantly, this defect was reversible, as interfering with the IL-2 signaling pathway helped reverse the abnormal differentiation and improved Ab responses. Thus, reversible reprogramming of memory Tfh cells in HIV-infected individuals could be used to enhance Ab responses. Altered microenvironmental conditions in lymphoid tissues leading to altered Tfh cell differentiation could provide one explanation for the poor responsiveness of HIV-infected individuals to new Ags. This explanation has important implications for the development of therapeutic interventions to enhance HIV- and vaccine-mediated Ab responses in patients under ART.

HIV-1 Capture and Transmission by Dendritic Cells: The Role of Viral Glycolipids and the Cellular Receptor Siglec-1

Dendritic cells (DCs) are essential in order to combat invading viruses and trigger antiviral responses. Paradoxically, in the case of HIV-1, DCs might contribute to viral pathogenesis through trans-infection, a mechanism that promotes viral capture and transmission to target cells, especially after DC maturation. In this review, we highlight recent evidence identifying sialyllactosecontaining gangliosides in the viral membrane and the cellular lectin Siglec-1 as critical determinants for HIV-1 capture and storage by mature DCs and for DC-mediated trans-infection of T cells. In contrast, DC-SIGN, long considered to be the main receptor for DC capture of HIV-1, plays a minor role in mature DC-mediated HIV-1 capture and trans-infection.

Direct Interrogation of Viral Peptides Presented by the Class I HLA of HIV-Infected T Cells

Identification of CD8+ cytotoxic T lymphocyte (CTL) epitopes has traditionally relied upon testing of overlapping peptide libraries for their reactivity with T cells in vitro. Here, we pursued deep ligand sequencing (DLS) as an alternative method of directly identifying those ligands that are epitopes presented to CTLs by the class I human leukocyte antigens (HLA) of infected cells. Soluble class I HLA-A*11:01 (sHLA) was gathered from HIV-1 NL4-3-infected human CD4+ SUP-T1 cells. HLA-A*11:01 harvested from infected cells was immunoaffinity purified and acid boiled to release heavy and light chains from peptide ligands that were then recovered by size-exclusion filtration. The ligands were first fractionated by high-pH high-pressure liquid chromatography and then subjected to separation by nano-liquid chromatography (nano-LC)–mass spectrometry (MS) at low pH. Approximately 10 million ions were selected for sequencing by tandem mass spectrometry (MS/MS). HLA-A*11:01 ligand sequences were determined with PEAKS software and confirmed by comparison to spectra generated from synthetic peptides. DLS identified 42 viral ligands presented by HLA-A*11:01, and 37 of these were previously undetected. These data demonstrate that (i) HIV-1 Gag and Nef are extensively sampled, (ii) ligand length variants are prevalent, particularly within Gag and Nef hot spots where ligand sequences overlap, (iii) noncanonical ligands are T cell reactive, and (iv) HIV-1 ligands are derived from de novo synthesis rather than endocytic sampling. Next-generation immunotherapies must factor these nascent HIV-1 ligand length variants and the finding that CTL-reactive epitopes may be absent during infection of CD4+ T cells into strategies designed to enhance T cell immunity.

HIV-1 immune activation induces siglec-1 expression and enhances viral trans-infection in blood and tissue myeloid cells

Background: Myeloid cells are key players in the recognition and response of the host against invading viruses. Paradoxically, upon HIV-1 infection, myeloid cells might also promote viral pathogenesis through trans-infection, a mechanism that promotes HIV-1 transmission to target cells via viral capture and storage. The receptor Siglec-1 (CD169) potently enhances HIV-1 trans-infection and is regulated by immune activating signals present throughout the course of HIV-1 infection, such as interferon α (IFNα). Results: Here we show that IFNα-activated dendritic cells, monocytes and macrophages have an enhanced ability to capture and trans-infect HIV-1 via Siglec-1 recognition of viral membrane gangliosides. Monocytes from untreated HIV-1-infected individuals trans-infect HIV-1 via Siglec-1, but this capacity diminishes after effective antiretroviral treatment. Furthermore, Siglec-1 is expressed on myeloid cells residing in lymphoid tissues, where it can mediate viral trans-infection. Conclusions: Siglec-1 on myeloid cells could fuel novel CD4+ T-cell infections and contribute to HIV-1 dissemination in vivo.

Garlic viral complex: identification of Potyviruses and Carlavirus in Central Brazil

Garlic viruses often occur in complex infections in nature. In this study, a garlic virus complex, collected in fields in Brazil, was purified. RT-PCR was performed using specific primers designed from the consensus regions of the coat protein genes of Onion yellow dwarf virus, a garlic strain (OYDV-G) and Leek yellow stripe virus (LYSV). cDNA of Garlic common latent virus (GCLV) was synthesized using oligo-dT and random primers. By these procedures individual garlic virus genomes were isolated and sequenced. The nucleotide sequence analysis associated with serological data reveals the presence of two Potyvirus OYDV-G and LYSV, and GCLV, a Carlavirus, simultaneously infecting garlic plants. Deduced amino acid sequences of the Brazilian isolates were compared with related viruses reported in different geographical regions of the world. The analysis showed closed relations considering the Brazilian isolates of OYDV-G and GCLV, and large divergence considering LYSV isolate. The detection of these virus species was confirmed by specific reactions observed when coat protein genes of the Brazilian isolates were used as probes in dot-blot and Southern blot hybridization assays. In field natural viral re-infection of virus-free garlic was evaluated.

Viral and cellular modulation of virus-induced apoptosis in experimental infection models

The aim of this study was to investigate herpes simplex virus type 1 (HSV-1)- and measles virus (MV)-induced cell death. HSV-1 with deletion in genes encoding infected cell protein (ICP)4 and protein kinase Us3 (d120) induced apoptosis and cathepsin activation in epithelial (HEp-2) and monocytic (U937) cells. Inhibition of cathepsin activity decreased the amount of d120-induced apoptosis indicating that d120-induced apoptosis could be cathepsin-mediated. Also, HSV-1 infection increased caspase activation suggesting that d120-induced apoptosis is probably caspase-mediated. Cystatin treatment decreased the activity of cathepsins and the replication of HSV-1 indicating that cathepsins contribute to HSV-1 infection. Interestingly, d120 induced also necroptosis in monocytic cells. This is the first report on necroptosis in HSV-1- infected cells. MV induced apoptosis in uninfected bystander T lymphocytes, probably via interaction of MV-infected monocytes with uninfected lymphocytes. The expression of death receptor Fas was clearly increased on the surface of lymphocytes. The number of apoptotic cells and the activation of cathepsins and caspases were increased in MVinfected U937 cells suggesting that MV-induced apoptosis could be cathepsin- and caspase-mediated. Cystatin treatment inhibited cathepsin activities but not MV-induced apoptosis. Besides HSV-1-induced apoptosis, innate immune responses were studied in HSV-1-infection. HSV-1 viruses with either ICP4 and Us3, or Us3 deletion only, increased the expression of Toll-like receptor (TLR)3 and stimulated its downstream pathways leading to increased expression of type I interferon gene and to functional interferons. These findings suggest that besides controlling apoptosis, HSV-1 ICP4 and Us3 genes are involved in the control of TLR3 response in infected cell.

Carga viral do papilomavirus humano na predição da gravidade de lesões cervicais em mulheres com atipias celulares na colpocitologia oncológica

OBJETIVO: avaliar o desempenho da carga viral do HPV por captura de híbridos II (CHII) na predição da gravidade das lesões cervicais. MÉTODOS: foram incluídas 309 mulheres admitidas por resultado anormal da colpocitologia oncológica (CO) entre agosto de 200 e novembro de 2002. Todas foram submetidas a avaliação histológica, sendo que a presença de neoplasia intra-epitelial cervical (NIC) grau 2 ou mais (NIC 3, carcinoma invasor) foi considerada doença grave. A CHII foi realizada para tipos de HPV de alto risco oncogênico e a carga viral medida em unidades relativas de luz (URL). O desempenho da CHII foi avaliado por curva receiver operating characteristics (ROC). RESULTADOS: na avaliação histológica, 140 (45,3%) mulheres apresentavam cervicite ou NIC 1 e 199 (54,7%), NIC 2/3, adenocarcinoma in situ ou câncer invasor. O melhor ponto de corte da CHII para a detecção de doença grave foi 35 URL, com sensibilidade de 69% e especificidade de 70%. O valor preditivo positivo das alterações compatíveis com lesão de alto grau na CO associado a CHII de 35 URL (unidades relativas de luz) foi de 88,2% para a detecção de NIC 2 ou mais. Já 95,7% das mulheres com lesões de baixo grau na CO e CHII menor que 1 URL não apresentaram lesões histológicas graves. CONCLUSÃO: o melhor desempenho da CHII no diagnóstico de NIC 2 ou lesão mais grave foi encontrado com 35 URL. A associação da CO com a CHII em diferentes cargas virais mostrou valores preditivos positivos e negativos muito altos.

Relação entre diagnóstico citopatológico de neoplasia intra-epitelial cervical e índices de células CD4+ e de carga viral em pacientes HIV-soropositivas

OBJETIVVO: relacionar a gravidade de lesão cervical diagnosticada por exame citopatológico à contagem de células CD4+ e à carga viral de RNA-HIV em pacientes HIV-soropositivas. MÉTODOS: foram avaliadas retrospectivamente, por meio de revisão de prontuários, 115 pacientes HIV-positivas atendidas em ambulatório de hospital universitário, no período de janeiro de 2002 até abril de 2003. Oitenta e três casos apresentaram diagnóstico de neoplasia intra-epitelial cervical (NIC) ao exame citopatológico, e trinta e dois, exames sem alterações. Todas as pacientes apresentavam contagem de células CD4+ e carga viral à época do exame. Os casos foram distribuídos quanto ao índice de células CD4+ em três grupos: CD4 acima de 500 cel/mm³, entre 200 e 500 cel/mm³ ou abaixo de 200 cel/mm³, e, em outros três grupos, quanto à carga viral de HIV: menor do que 10.000 cópias RNA-HIV/mL, entre 10.000 e 100.000 cópias RNA-HIV/mL ou maior do que 100.000 cópias RNA-HIV/mL. A verificação da hipótese de associação foi realizada por meio do teste exato de Fisher. RESULTADOS: das 83 pacientes com NIC citopatológico, 73% apresentaram contagem de células CD4+ abaixo de 500 células/mm³. Em qualquer das faixas de contagem de células CD4+, mais da metade das pacientes apresentavam NIC I citopatológico. Quanto à carga viral de HIV, 71,7% das pacientes com menor carga viral de HIV apresentaram NIC I, ao passo que 11,3% revelaram NIC III. Já no grupo com maior carga viral (100.000 cópias/mL), em 61,5% do total de pacientes o exame citopatológico foi compatível com NIC I, e 30,8% com NIC III. CONCLUSÃO: houve evidência de associação entre carga viral e NIC (p=0.013), não sendo observado o mesmo em relação à contagem de linfócitos CD4+. A presença de infecção secundária cervicovaginal foi considerada possível fator confundidor.

Associação entre a carga viral e os linfócitos T CD4+ com as lesões intra-epiteliais do colo uterino em mulheres infectadas pelo vírus da imunodeficiência humana

OBJETIVOS: verificar se a contagem de linfócitos T CD4+ e a carga viral do HIV têm influência na presença de lesões intra-epiteliais cervicais (SIL). MÉTODOS: estudo transversal, no qual foram selecionadas 134 mulheres HIV-positivas, todas submetidas à biópsia do colo uterino, quantificação da carga viral do HIV e contagem de linfócitos T CD4+. Os valores laboratoriais da quantificação da carga viral e da contagem de linfócitos T CD4+ foram obtidos antes da realização da biópsia, tendo sido estabelecidos cortes para o estudo da carga viral (<400 cópias/mL; 401 a 50.000 cópias/mL; >50.000 cópias/mL) e contagem de linfócitos T CD4+ (<200 células/mm³; 200 a 350 células/mm³; >350 células/mm³). Foram realizados os testes chi2, chi2 de tendência linear, chi2 de Mantel-Haenszel e análise de variância. Estabeleceu-se significância estatística para p<0,05 e intervalo de confiança a 95%. RESULTADOS: não houve tendência de risco para as mulheres HIV-positivas apresentarem SIL com o aumento da carga viral ou diminuição dos linfócitos T CD4+. Comparando-se a carga viral com a presença ou ausência de SIL, estratificada pelo tempo em que foi quantificada, houve diferença significante para valores acima de 400 cópias/mL (OR: 3,17; IC 95%: 1,02-9,93; p=0,048). Nenhuma associação foi encontrada para a contagem de linfócitos T CD4+ com a presença da SIL. CONCLUSÃO: as pacientes com carga viral do HIV maior que 400 cópias/mL, quantificada antes da biópsia do colo uterino, apresentaram chance 3,17 vezes maior de desencadear SIL. A contagem de linfócitos T CD4+ não influenciou no aparecimento da SIL.