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1.
Pan Afr Med J ; 42: 58, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35949454

RESUMO

The non-Hodgkin's lymphomas (NHLs) are a diverse group of malignancies that originate in lymphoid cells, heterogeneous in clinical behavior, morphology, cellular origin, etiology, and pathogenesis. A viral infectious etiology had been associated with them. This study aimed to investigate the seroprevalence of Epstein-Barr virus (EBV), Hepatitis B virus (HBV), Hepatitis C virus (HCV) and Human Immunodeficiency Virus (HIV) among patients with NHL at the Yaoundé General Hospital (YGH). Participants for this cross-sectional study were recruited at the medical oncology unit from October 2018 to December 2019. For each patient fulfilling the inclusion criteria, five milliliters of blood were drawn at the crook of their elbows in EDTA tubes. Then, EBV, HIV, HBV, and HVC screening were done using the Rapid Diagnostic Tests (RDTs); Bio-Rad EBV, Alere Determine HIV-1/HIV-2, HBV the best diagnostic and HVC Wondfo biotech respectively. Participants were made up of sixty-three males (69.23%) and twenty-eight females (30.77%). Their ages ranged from nineteen to seventy-eight years, with a mean ± SD of 56.5 ± 15.5. There were eight HIV patients (8.8%) followed by five EBV or HBV patients (5.5%). Three patients were coinfected with HIV+EBV (3.3%) while only two patients (2.2%) had HCV. Only HIV and EBV were seen coinfected. The presence of HBV and HCV in patients with NHL reveals the need to understand how these viruses induce lymphoproliferative diseases, more precisely, the non-Hodgkin´s lymphoma.


Assuntos
Infecções por Vírus Epstein-Barr , Infecções por HIV , Hepatite C , Linfoma não Hodgkin , Adulto , Idoso , Camarões/epidemiologia , Estudos Transversais , Infecções por Vírus Epstein-Barr/complicações , Infecções por Vírus Epstein-Barr/diagnóstico , Infecções por Vírus Epstein-Barr/epidemiologia , Feminino , Infecções por HIV/complicações , Infecções por HIV/epidemiologia , HIV-2 , Hepacivirus , Vírus da Hepatite B , Hepatite C/complicações , Hepatite C/epidemiologia , Herpesvirus Humano 4 , Hospitais Gerais , Humanos , Linfoma não Hodgkin/epidemiologia , Linfoma não Hodgkin/patologia , Masculino , Pessoa de Meia-Idade , Estudos Soroepidemiológicos , Adulto Jovem
3.
J Mol Biol ; 434(19): 167753, 2022 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-35868362

RESUMO

Human immunodeficiency virus (HIV) Gag drives virus particle assembly. The capsid (CA) domain is critical for Gag multimerization mediated by protein-protein interactions. The Gag protein interaction network defines critical aspects of the retroviral lifecycle at steps such as particle assembly and maturation. Previous studies have demonstrated that the immature particle morphology of HIV-2 is intriguingly distinct relative to that of HIV-1. Based upon this observation, we sought to determine the amino acid residues important for virus assembly that might help explain the differences between HIV-1 and HIV-2. To do this, we conducted site-directed mutagenesis of targeted locations in the HIV-2 CA domain of Gag and analyzed various aspects of virus particle assembly. A panel of 31 site-directed mutants of residues that reside at the HIV-2 CA inter-hexamer interface, intra-hexamer interface and CA inter-domain linker were created and analyzed for their effects on the efficiency of particle production, particle morphology, particle infectivity, Gag subcellular distribution and in vitro protein assembly. Seven conserved residues between HIV-1 and HIV-2 (L19, A41, I152, K153, K157, N194, D196) and two non-conserved residues (G38, N127) were found to significantly impact Gag multimerization and particle assembly. Taken together, these observations complement structural analyses of immature HIV-2 particle morphology and Gag lattice organization as well as provide important comparative insights into the key amino acid residues that can help explain the observed differences between HIV immature particle morphology and its association with virus replication and particle infectivity.


Assuntos
Infecções por HIV , HIV-1 , Aminoácidos/genética , Aminoácidos/metabolismo , Capsídeo/química , Proteínas do Capsídeo/química , Infecções por HIV/metabolismo , HIV-1/genética , HIV-1/metabolismo , HIV-2/genética , Humanos , Mutagênese , Montagem de Vírus/genética , Produtos do Gene gag do Vírus da Imunodeficiência Humana/metabolismo
4.
Front Cell Infect Microbiol ; 12: 916487, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35711654

RESUMO

Given the high variability and drug-resistance problem by human immunodeficiency virus type 1 (HIV-1), the development of bispecific or multi-specific inhibitors targeting different steps of HIV entry is highly appreciated. We previously generated a very potent short-peptide-based HIV fusion inhibitor 2P23. In this study, we designed and characterized a bifunctional inhibitor termed 2P23-iMab by genetically conjugating 2P23 to the single-chain variable fragment (scFv) of ibalizumab (iMab), a newly approved antibody drug targeting the cell receptor CD4. As anticipated, 2P23-iMab could bind to the cell membrane through CD4 anchoring and inhibit HIV-1 infection as well as viral Env-mediated cell-cell fusion efficiently. When tested against a large panel of HIV-1 pseudoviruses with different subtypes and phenotypes, 2P23-iMab exhibited dramatically improved inhibitory activity than the parental inhibitors; especially, it potently inhibited the viruses not being susceptible to iMab. Moreover, 2P23-iMab had a dramatically increased potency in inhibiting two panels of HIV-1 mutants that are resistant to T-20 or 2P23 and the infections of HIV-2 and simian immunodeficiency virus (SIV). In conclusion, our studies have provided new insights into the design of novel bispecific HIV entry inhibitors with highly potent and broad-spectrum antiviral activity.


Assuntos
Inibidores da Fusão de HIV , Infecções por HIV , HIV-1 , Vírus da Imunodeficiência Símia , Animais , Antirretrovirais , Inibidores da Fusão de HIV/farmacologia , Infecções por HIV/tratamento farmacológico , HIV-2/fisiologia , Proteínas Virais de Fusão
5.
Transfus Clin Biol ; 29(3): 205-208, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35728751

RESUMO

OBJECTIVE: This study compared two assays aimed at confirming the presence of anti-HCV antibodies (Ab) after a positive screening: Geenius HCV supplemental assay (Bio-Rad, Marne la Coquette, France) and the Inno-LIA HCV score assay (Fujirebio, Les Ulis, France). MATERIAL AND METHODS: A total of 180 archived samples were investigated including 119 samples collected at different stages of HCV infection in 25 hemodialyzed patients who underwent HCV seroconversion, 14 samples from 4 commercial seroconversion panels, 47 Ab positive/HCV-RNA positive blood donations of which 7 showing an single reactivity in confirmatory assays. Samples were investigated and results were interpreted with the two assays according to the manufacturers' instructions. RESULTS: Overall, Geenius and Inno-LIA were concordant for 84% (151/180) samples: 38 negative, 17 indeterminate and 96 positive. Of the 29 discrepant results, 26 were overclassified with Inno-LIA. HCV seroconversion was detected with Inno-LIA 4 and 7 days prior to Geenius in two panels. The high positive rate observed with Inno-LIA (64%) compared to Geenius (54%) was mainly due to low reactivities considered positive according to interpretation criteria, which could affect specificity. CONCLUSION: Although HCV supplemental assays are not recommended for the diagnostic of HCV infection, which is primarily based on HCV-RNA testing, both assays are suitable as second line anti-HCV tests when Ab screening is positive and RNA testing cannot be performed. Moreover, Geenius system provides an objective result in less than 30minutes, which is compatible when a rapid diagnostic is required.


Assuntos
Infecções por HIV , HIV-1 , Infecções por HIV/diagnóstico , HIV-2 , Anticorpos Anti-Hepatite C , Humanos , RNA , Sensibilidade e Especificidade
6.
Indian J Med Microbiol ; 40(3): 370-373, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35680473

RESUMO

PURPOSE: Accurate HIV diagnosis is essential for appropriate patient care. This present study evaluated the performance of two different new rapid HIV diagnostic tests; 1) TRUSTline HIV-1/2 Ab rapid test (Athenese-DxPvt. Ltd, Chennai, India)and 2) OnSite HIV 1/2 Ab Plus Combo Rapid Test (CTK Biotech Inc., San Diego, USA) and also validated ALTA Rapid Test Reader (RTR-1) (CTK Biotech Inc., San Diego, USA), the device is a user-friendly and image-analysis based qualitative/semi-quantitative tabletop reader. METHODS: A total of n â€‹= â€‹500 characterized specimens were used for this evaluation and the results of the new test kits (TRUSTline and OnSite) were also compared with 4th generation ELISA kit (Genescreen™Ultra HIV Ag-Ab ELISA) and 3 other commercially available rapid tests that were in the market; 1)SD Bioline™ HIV 1/2 3.0, 2) Aspen® HIV 1/2 Rapid Ab Test and 3) Diagnostic enterprises HIVTRI-DOT. The test band intensities of the TRUSTline and OnSite tests were measured in an ALTA rapid test reader and compared with the naked eye reading. RESULTS: The sensitivity, specificity, positive predictive value, negative predictive value and efficacy of TRUSTline and OnSite were 100%, 99.6%, 99.5%, 100% and 99.8% and 100%, 100%, 100%, 100% and 100% respectively. CONCLUSIONS: The 'TRUSTline HIV-1/2' and 'OnSite HIV 1/2' kits are suitable to use in the HIV testing algorithm. Use of the ALTA rapid test reader could be user's friendly in the field level testing in resource-limited settings".


Assuntos
Infecções por HIV , Ensaio de Imunoadsorção Enzimática/métodos , Anticorpos Anti-HIV , Infecções por HIV/diagnóstico , HIV-2 , Humanos , Índia , Valor Preditivo dos Testes , Kit de Reagentes para Diagnóstico , Sensibilidade e Especificidade
7.
Eur J Med Chem ; 237: 114414, 2022 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-35512567

RESUMO

We have recently described a novel family of compounds of reduced size and dual anti-HIV and anti-EV71 activity that encompasses tripodal and tetrapodal derivatives. The tripodal prototype, AL-470, has a nitro group at the focal point of the central scaffold and three attached tryptophan residues, each of which bearing an isophthaloyl moiety at the C2 position of the indole ring. A nitro to amino substitution has allowed us now to introduce a chemically addressable functionality to perform further structural modifications consisting of both direct and linker-mediated attachment of several aromatic groups, including the fluorescent dye Alexa Fluor 647 and the antibody-recruiting 2,4-dinitrophenyl motif. Some of the derivatives turned out to be more potent and selective than AL-470 against HIV-1, HIV-2 and EV-A71. The fluorescent probe demonstrated a specific tropism for intestines and lungs, two important niches for the human microbiome in health and disease.


Assuntos
Dendrímeros , Enterovirus Humano A , Infecções por Enterovirus , Inibidores da Fusão de HIV , HIV-1 , Dendrímeros/química , Inibidores da Fusão de HIV/farmacologia , HIV-2 , Humanos , Internalização do Vírus
8.
Int J Mol Sci ; 23(9)2022 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-35563157

RESUMO

HIV-2, compared to HIV-1, elicits potent and broadly neutralizing antibodies, and uses a broad range of co-receptors. However, both sensitivity to neutralization and breadth of co-receptor use varies between HIV-2 isolates, and the molecular background is still not fully understood. Thus, in the current study, we have deciphered relationships between HIV-2 neutralization sensitivity, co-receptor use and viral envelope glycoprotein (Env) molecular motifs. A panel of primary HIV-2 isolates, with predefined use of co-receptors, was assessed for neutralization sensitivity using a set of HIV-2 Env-directed monoclonal antibodies and co-receptor indicator cell lines. Neutralization sensitivity of the isolates was analysed in relation target cell co-receptor expression, in addition to amino acid motifs and predicted structures of Env regions. Results showed that HIV-2 isolates were more resistant to neutralizing antibodies when entering target cells via the alternative co-receptor GPR15, as compared to CCR5. A similar pattern was noted for isolates using the alternative co-receptor CXCR6. Sensitivity to neutralizing antibodies appeared also to be linked to specific Env motifs in V1/V2 and C3 regions. Our findings suggest that HIV-2 sensitivity to neutralization depends both on which co-receptor is used for cell entry and on specific Env motifs. This study highlights the multifactorial mechanisms behind HIV-2 neutralization sensitivity.


Assuntos
Infecções por HIV , HIV-1 , Anticorpos Neutralizantes , Anticorpos Amplamente Neutralizantes , Anticorpos Anti-HIV , Proteína gp120 do Envelope de HIV , HIV-1/metabolismo , HIV-2/metabolismo , Humanos , Receptores Acoplados a Proteínas G , Receptores de Peptídeos , Produtos do Gene env do Vírus da Imunodeficiência Humana
9.
J Clin Virol ; 152: 105189, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35640401

RESUMO

BACKGROUND: Although the number of HIV-2-infected individuals is quite low in Japan, at least three groups of HIV-2 (A, B and CRF01_AB) have been detected thus far. In particular, CRF01_AB HIV-2 cases have been found only in limited areas, Cote d'Ivoire and Japan. Here, we demonstrate that Geenius HIV 1/2 Confirmatory Assay (Geenius, Bio-Rad Laboratories) is able to detect HIV-2 samples, including groups A, B and CRF01_AB, isolated in Japan. STUDY DESIGN: A total of 57 plasma samples, including three panels (Ⅰ: HIV-2-positive samples [n=9], Ⅱ: HIV-1 infection with HIV-2 antibody cross-reactivity samples [n=37], and Ⅲ: HIV negative with biological false-positive HIV-2 samples [n=11]) were tested by Geenius. RESULTS: Geenius determined Panel I to be "HIV-2 positive with/without HIV-1 cross-reactivity (n=4, respectively)", including HIV-2 group A and CRF01_AB. In the case with HIV-2 group B, all bands were detected, resulting in a Geenius interpretation of "HIV positive untypable". Geenius classified Panels II and III as "HIV-1 positive (n=37)" or "HIV negative (n=9)", "HIV indeterminate (n=1)" and "HIV-2 indeterminate (n=1)", suggesting 95.8% HIV-2 differentiation by Geenius. CONCLUSIONS: With Geenius, there were fewer false-positives for HIV-1/-2 negativity and fewer cross-reactions with HIV-2 among HIV-1-positive samples. Additionally, the assay could detect HIV-2 genetic group CRF01_AB. Geenius can be expected to be a useful diagnostic tool that is an alternative to conventional Western blotting.


Assuntos
Infecções por HIV , Soropositividade para HIV , HIV-1 , Anticorpos Anti-HIV , HIV-1/genética , HIV-2 , Humanos , Japão , Sensibilidade e Especificidade
10.
Clin Lab ; 68(4)2022 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-35443578

RESUMO

BACKGROUND: The Architect HIV Ag/Ab Combo has been implemented worldwide as a screening test for more than ten years. However, its high sensitivity may lead to false-positive results in a low-prevalence setting. METHODS: This study was carried out to evaluate the performance of the Architect HIV Ag/Ab Combo based on the sample-to-cutoff (S/CO) ratios, to explore the optimal cutoff value to predict HIV infection and reduce the frequency of false-positive results. A retrospective analysis of clinical samples using the Architect HIV Ag/Ab Combo between July 2011 and February 2020 was performed. The sensitivity, specificity, positive predictive value (PPV), and false-positive rate (FPR) were evaluated and the receiver operating characteristic curve (ROC) analysis was used to determine the optimal cutoff value to predict HIV infection. RESULTS: During the study period, 531 out of 692,155 samples were repeatedly reactive by the Architect HIV Ag/Ab Combo. The median S/CO value of HIV-positive were significantly higher than that of false-positive. The PPV of males (85.68%) was significantly higher than that of females (47.89%). The optimal cutoff value estimated by ROC analysis was 8.96 with the highest sum of sensitivity (100.00%) and specificity (100.00%) for males. However, for females, the optimal cutoff value was 26.97 with the highest sum of sensitivity (100.00%) and specificity (100.00%). CONCLUSIONS: For the Architect HIV Ag/Ab Combo, the optimal cutoff value needs to be set for the different genders to predict the final status of HIV infection reliably.


Assuntos
Infecções por HIV , HIV-1 , Reações Falso-Positivas , Feminino , Anticorpos Anti-HIV , Antígenos HIV , Infecções por HIV/diagnóstico , HIV-2 , Humanos , Imunoensaio/métodos , Masculino , Estudos Retrospectivos , Sensibilidade e Especificidade
11.
Adv Exp Med Biol ; 1366: 65-85, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35412135

RESUMO

The discovery of the G-protein coupled-receptor (GPCR) CXCR4 as a major coreceptor of HIV-1 entry about three decades ago explained why the chemokine SDF-1/CXCL12 inhibits specific viral strains. The knowledge that RANTES, MlP-1α, and MlP-1ß specifically inhibit other primary HIV-1 strains allowed the rapid discovery of CCR5 as second major viral coreceptor and explained why individuals with deletions in CCR5 are protected against sexual HIV-1 transmission. Here, we provide an update on endogenous ligands of GPCRs that act as endogenous inhibitors of HIV-1, HIV-2, and simian immunodeficiency virus (SIV) entry. In addition, we summarize the development of optimized derivatives of endogenous GPCR ligands and their perspectives as antiviral agents and beyond. Finally, we provide examples for other endogenous peptides that may contribute to our innate immune defense against HIV-1 and other viral pathogens and offer prospects for preventive or therapeutic development.


Assuntos
Inibidores da Fusão de HIV , Infecções por HIV , HIV-1 , Animais , Inibidores da Fusão de HIV/farmacologia , Inibidores da Fusão de HIV/uso terapêutico , Infecções por HIV/tratamento farmacológico , HIV-1/metabolismo , HIV-1/fisiologia , HIV-2/metabolismo , HIV-2/fisiologia , Humanos , Ligantes , Peptídeos/uso terapêutico , Receptores CCR5 , Receptores Acoplados a Proteínas G/uso terapêutico , Transdução de Sinais , Vírus da Imunodeficiência Símia
12.
PLoS One ; 17(4): e0266082, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35381042

RESUMO

BACKGROUND: Our objective was to assess differences in TB treatment outcomes between individuals who were HIV negative, HIV positive on anti-retroviral treatment (ART) and HIV positive not on ART, at TB treatment initiation at a rural district hospital in Eastern Cape, South Africa. METHODS: This was a retrospective cohort study of individuals diagnosed with TB between January 2017 and April 2020 at a district hospital. Adults 15 years and over with reported HIV status and treatment outcome were included (N = 711). A categorical outcome with three levels was considered: unfavorable, down referral, and success. We report descriptive statistics for the association between HIV and ART status and treatment outcome using Chi-square and Fisher's exact tests. A multinomial baseline logit model was used to estimate odds ratios for treatment outcomes. RESULTS: Overall, 59% of included patients were HIV positive with 75% on ART. Eighty-eight patients 12% had an unfavorable outcome. Half of all patients were down referred with an additional 37% having a successful outcome. Individuals without HIV were more likely to be down referred (versus unfavorable) compared to individuals with untreated HIV (2.90 OR, 1.36, 6.17 95% CI). There was a greater likelihood for individuals without HIV having a successful TB treatment outcome compared to individuals with untreated HIV (4.98 OR, 2.07, 11.25 95% CI). CONCLUSION: The majority of individuals had positive TB treatment outcomes (down referred or success). However, people without HIV had nearly five times greater odds of having successful outcomes than those with untreated HIV.


Assuntos
Infecções por HIV , Tuberculose , Adulto , Antituberculosos/uso terapêutico , Infecções por HIV/complicações , Infecções por HIV/tratamento farmacológico , Infecções por HIV/epidemiologia , HIV-2 , Hospitais de Distrito , Humanos , Estudos Retrospectivos , África do Sul/epidemiologia , Resultado do Tratamento , Tuberculose/complicações , Tuberculose/tratamento farmacológico , Tuberculose/epidemiologia
13.
J Clin Microbiol ; 60(5): e0234821, 2022 05 18.
Artigo em Inglês | MEDLINE | ID: mdl-35387497

RESUMO

Diagnostic assays that can simultaneously determine the presence of infection with multiple pathogens are key for diagnosis and surveillance. Current multiplex diagnostic assays are complex and often have limited availability. We developed a simple, multianalyte, pathogen detection assay for screening and serosurveillance using the Luminex Magpix platform that is high throughput and can be helpful in monitoring multiple diseases. The Luminex bead-based 10-plex immunoassay for the detection of HIV-1, HIV-2, Treponema pallidum, hepatitis B virus (HBV), hepatitis C virus (HCV), herpes simplex virus 1 (HSV-1), and HSV-2 infections was accomplished by coupling beads with specific antigens to detect IgG antibodies in plasma or serum samples. Each coupled antigen was systematically optimized, and the performance was evaluated using a panel of well-characterized specimens (n = 417) that contained antibodies to HIV-1, HIV-2, T. pallidum, HBV, HCV, HSV-1, and HSV-2. The multiplex assay had a sensitivity of 92.2% (95% Clopper-Pearson confidence interval [CI], 90.2 to 94.0%) and a specificity of 98.1% (95% CI, 97.6 to 98.7%). The sensitivities and specificities for disease-specific biomarker detection ranged from 68.7 to 100% and 95.6 to 100%, respectively. The results showed that the 10-plex immunoassay had an overall agreement of 96.7% (95% CI, 96.7 to 97.3%) with reference tests and a corresponding kappa value of 0.91 (95% CI, 0.90 to 0.93). Kappa values for the individual pathogens ranged from 0.69 to 1.00. The assay is robust and allows the simultaneous detection of antibodies to multiple antigens using a small sample volume in a high-throughput format. This assay has the potential to simplify disease surveillance by providing an alternative to expensive and highly specialized individual tests.


Assuntos
Infecções por HIV , HIV-1 , Hepatite C , Herpes Simples , Sífilis , HIV-2 , Hepacivirus , Vírus da Hepatite B , Hepatite C/diagnóstico , Herpes Simples/diagnóstico , Humanos , Sensibilidade e Especificidade , Sífilis/diagnóstico , Sífilis/epidemiologia , Treponema pallidum
14.
PLoS One ; 17(4): e0267402, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35476802

RESUMO

Although there have been great advancements in the field of HIV treatment and prevention, there is no cure. There are two types of HIV: HIV-1 and HIV-2. In addition to genetic differences between the two types of HIV, HIV-2 infection causes a slower disease progression, and the rate of new HIV-2 infections has dramatically decreased since 2003. Like HIV-1, HIV-2 is capable of establishing latent infection in CD4+ T cells, thereby allowing the virus to evade viral cytopathic effects and detection by the immune system. The mechanisms underlying HIV latency are not fully understood, rendering this a significant barrier to development of a cure. Using RT-ddPCR, we previously demonstrated that latent infection with HIV-1 may be due to blocks to HIV transcriptional elongation, distal transcription/polyadenylation, and multiple splicing. In this study, we describe the development of seven highly-specific RT-ddPCR assays for HIV-2 that can be applied to the study of HIV-2 infections and latency. We designed and validated seven assays targeting different HIV-2 RNA regions along the genome that can be used to measure the degree of progression through different blocks to HIV-2 transcription and splicing. Given that HIV-2 is vastly understudied relative to HIV-1 and that it can be considered a model of a less virulent infection, application of these assays to studies of HIV-2 latency may inform new therapies for HIV-2, HIV-1, and other retroviruses.


Assuntos
Infecções por HIV , Soropositividade para HIV , HIV-1 , Infecção Latente , HIV-1/genética , HIV-2/genética , Humanos , Latência Viral/genética
15.
AIDS ; 36(8): 1055-1060, 2022 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-35262531

RESUMO

OBJECTIVE: Treatment of multidrug-resistant HIV-2 is an emerging issue, because of the rapid selection of mutations at time of virological failure and the low number of antiretrovirals active on HIV-2. The aim of this study was to determine the susceptibility of HIV-2 primary isolates to ibalizumab, a long-acting monoclonal antibody that binds to CD4 that is approved for the treatment of MDR HIV-1. METHODS: In-vitro phenotypic susceptibility of 16 HIV-2 primary isolates was measured using a modified version of the ANRS peripheral blood mononuclear cells (PBMC) assay. Susceptibility to ibalizumab was assessed through 50% inhibitory concentrations and maximum percentage inhibitions (MPI), and gp105 was sequenced to look for determinants of reduced susceptibility. RESULTS: Ibalizumab inhibited viral replication of all 16 isolates, with a median IC 50 value of 0.027 µg/ml (range = 0.001-0.506 µg/ml), and a median MPI of 93%. Although two isolates presented higher IC 50 (above 0.1 µg/ml), they did not exhibit a loss of potential N-linked glycosylation sites in V5 loop, as reported in HIV-1 strains with reduced susceptibility. However, both presented shorter V1 and V2 loops than the HIV-2 reference strain. CONCLUSION: Ibalizumab inhibits HIV-2 replication, with IC 50 and MPI in the range of those reported for HIV-1. These in vitro data support the use of ibalizumab in patients with MDR HIV-2, in combination with an optimized background regimen.


Assuntos
Fármacos Anti-HIV , Infecções por HIV , HIV-1 , Fármacos Anti-HIV/uso terapêutico , Anticorpos Monoclonais/efeitos adversos , Infecções por HIV/tratamento farmacológico , HIV-2 , Humanos , Leucócitos Mononucleares
16.
J Infect Dis ; 226(3): 497-509, 2022 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-35134180

RESUMO

BACKGROUND: Integrase inhibitors (INIs) are a key component of antiretroviral therapy for human immunodeficiency virus-1 (HIV-1) and HIV-2 infection. Although INI resistance pathways are well-defined for HIV-1, mutations that emerge in HIV-2 in response to INIs are incompletely characterized. METHODS: We performed systematic searches of GenBank and HIV-2 drug resistance literature to identify treatment-associated mutations for phenotypic evaluation. We then constructed a library of 95 mutants of HIV-2ROD9 that contained single or multiple amino acid changes in the integrase protein. Each variant was tested for susceptibility to raltegravir and dolutegravir using a single-cycle indicator cell assay. RESULTS: We observed extensive cross-resistance between raltegravir and dolutegravir in HIV-2ROD9. HIV-2-specific integrase mutations Q91R, E92A, A153G, and H157Q/S, which have not been previously characterized, significantly increased the half maximum effective concentration (EC50) for raltegravir when introduced into 1 or more mutational backgrounds; mutations E92A/Q, T97A, and G140A/S conferred similar enhancements of dolutegravir resistance. HIV-2ROD9 variants encoding G118R alone, or insertions of residues SREGK or SREGR at position 231, were resistant to both INIs. CONCLUSIONS: Our analysis demonstrates the contributions of novel INI-associated mutations to raltegravir and dolutegravir resistance in HIV-2. These findings should help to improve algorithms for genotypic drug resistance testing in HIV-2-infected individuals.


Assuntos
Fármacos Anti-HIV , Infecções por HIV , Inibidores de Integrase de HIV , Integrase de HIV , HIV-1 , Farmacorresistência Viral , HIV-2 , Compostos Heterocíclicos com 3 Anéis , Humanos , Mutação , Oxazinas , Piperazinas , Piridonas , Raltegravir Potássico
17.
Indian J Med Microbiol ; 40(1): 122-126, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35016792

RESUMO

PURPOSE: Development of a simple, affordable, and sensitive method based on gene amplification by PCR followed by liquid hybridization for detection of HIV-1 & 2, HCV and HBV in plasma samples (NAT-ELISA) for detection of these viruses particularly in their window period. METHODS: Viral nucleic acid extracted from WHO International Standards for HIV1, HIV2, HCV and HBV and 199 blood donor plasma samples were amplified by reverse transcription -PCR with forward and biotinylated reverse primers designed from the conserved regions of p-24 gene of HIV-1 and HIV-2, 5' UTR of HCV and middle part of S gene of HBV respectively. The biotinylated amplicons were immobilized on streptavidin coated ELISA plates, denatured chemically, and were hybridized with digoxigenin labelled specific oligonucleotide probes of HIV-1, HIV2, HCV and HBV. Hybridization signals were measured colorimetrically by indirect ELISA using anti-digoxigenin HRP conjugate and TMB substrate at 450 â€‹nm. Analytical Sensitivity or lower limit of detection (LOD) of this assay was determined with WHO standards. RESULTS: PCR amplified products of WHO standards were 321bp of HIV-1, 291bp of HIV- 2, 229bp of HBV, and 105bp of HCV. The LOD95 and LOD99.7 endpoints of HIV1, HIV2, HCV and HBV were 13, 6, 15 and 11 IU/ml and 15, 7, 17 and 12 IU/ml respectively. Diagnostic sensitivity and specificity of NAT-ELISA assay were calculated on 199 samples and was 97.4% and 99.4% respectively. CONCLUSIONS: The results suggest that this assay is highly suitable for the blood banks which do not have facilities for exorbitantly expensive NAT test for the detection of these viruses during their window period particularly in the blood donors who test negative by antibody/antigen screening tests.


Assuntos
Infecções por HIV , HIV-1 , Hepatite C , Doadores de Sangue , DNA Viral/genética , Ensaio de Imunoadsorção Enzimática , Infecções por HIV/diagnóstico , HIV-1/genética , HIV-2/genética , Hepacivirus/genética , Vírus da Hepatite B/genética , Hepatite C/diagnóstico , Humanos , Reação em Cadeia da Polimerase , Ácidos Urônicos
18.
Retrovirology ; 19(1): 2, 2022 01 24.
Artigo em Inglês | MEDLINE | ID: mdl-35073912

RESUMO

BACKGROUND: The NF-κB family of transcription factors and associated signalling pathways are abundant and ubiquitous in human immune responses. Activation of NF-κB transcription factors by viral pathogen-associated molecular patterns, such as viral RNA and DNA, is fundamental to anti-viral innate immune defences and pro-inflammatory cytokine production that steers adaptive immune responses. Diverse non-viral stimuli, such as lipopolysaccharide and cytokines, also activate NF-κB and the same anti-pathogen gene networks. Viruses adapted to human cells often encode multiple proteins targeting the NF-κB pathway to mitigate the anti-viral effects of NF-κB-dependent host immunity. RESULTS: In this study we have demonstrated using a variety of assays, in a number of different cell types including primary cells, that plasmid-encoded or virus-delivered simian immunodeficiency virus (SIV) accessory protein Vpx is a broad antagonist of NF-κB signalling active against diverse innate NF-κB agonists. Using targeted Vpx mutagenesis, we showed that this novel Vpx phenotype is independent of known Vpx cofactor DCAF1 and other cellular binding partners, including SAMHD1, STING and the HUSH complex. We found that Vpx co-immunoprecipitated with canonical NF-κB transcription factor p65, but not NF-κB family members p50 or p100, preventing nuclear translocation of p65. We found that broad antagonism of NF-κB activation by Vpx was conserved across distantly related lentiviruses as well as for Vpr from SIV Mona monkey (SIVmon), which has Vpx-like SAMHD1-degradation activity. CONCLUSIONS: We have discovered a novel mechanism by which lentiviruses antagonise NF-κB activation by targeting p65. These findings extend our knowledge of how lentiviruses manipulate universal regulators of immunity to avoid the anti-viral sequelae of pro-inflammatory gene expression stimulated by both viral and extra-viral agonists. Importantly our findings are also relevant to the gene therapy field where virus-like particle associated Vpx is routinely used to enhance vector transduction through antagonism of SAMHD1, and perhaps also through manipulation of NF-κB.


Assuntos
HIV-2 , Vírus da Imunodeficiência Símia , Animais , HIV-2/genética , NF-kappa B/metabolismo , Proteína 1 com Domínio SAM e Domínio HD/metabolismo , Vírus da Imunodeficiência Símia/genética , Proteínas Virais Reguladoras e Acessórias/genética , Proteínas Virais Reguladoras e Acessórias/metabolismo
19.
J Clin Virol ; 146: 105058, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34973475

RESUMO

BACKGROUND: The Centers for Disease Control and Prevention (CDC) issued updated guidelines for HIV testing in 2014. These guidelines recommend screening using an HIV-1/2 antigen/antibody (Ag/Ab) test and create the ability to identify algorithm-defined acute HIV infections (AHI). The guidelines also recommend laboratory confirmation of preliminary positive point of care (POC) rapid HIV test results and specimens from high-risk individuals who test POC rapid negative. The Florida Public Health Laboratory (FPHL) switched from an antibody-only algorithm to the CDC recommended algorithm April 16, 2012. OBJECTIVES: To analyze the FPHL HIV testing data and evaluate the impact of the CDC recommended algorithm on the identification of AHI, time to result and inconclusive HIV reports. STUDY DESIGN: FPHL HIV test data, for the period January 1, 2010 through December 31, 2019, was reviewed to determine the number of AHI cases identified, the number of indeterminate HIV results and the time from specimen receipt to result for tests in the antibody-only and CDC recommended algorithms. In addition, POC rapid results were compared to laboratory-based results for AHI cases for which rapid test results were available. RESULTS: There was no difference in time to result between the antibody-only and CDC recommended algorithms for HIV negative specimens. The time to result for HIV-1 positive specimens decreased from an average of 5 days with the antibody-only algorithm to an average of 1 day with the CDC recommended algorithm. The average number of indeterminate results per month decreased from 6.25 per month with the antibody-only algorithm to an average of 2.5 per month using the CDC recommended algorithm. Despite HIV seropositivity decreasing by 0.5% during the study period (2012 = 3.1% [3,892/124,394]: 2019 = 2.6% [2,456/95,525]), AHI cases increased annually from a total of 4 in 2012 to over 50 in 2019 and cases were identified in 30 of 67 Florida counties. The increase in identification of AHIs is credited to educational efforts with healthcare providers to encourage further testing on individuals with risk factors for HIV and a recent POC HIV-1/2 rapid negative test result. CONCLUSIONS: Data indicates that performing HIV testing according to the CDC recommended algorithm decreased time to result for HIV positive results, reduced the number of indeterminate results and identified algorithm-defined AHI. In addition, laboratory-based testing is warranted for high-risk individuals who test negative by POC rapid testing.


Assuntos
Infecções por HIV , HIV-1 , Algoritmos , Centers for Disease Control and Prevention, U.S. , Infecções por HIV/diagnóstico , Infecções por HIV/epidemiologia , Teste de HIV , HIV-2 , Humanos , Imunoensaio/métodos , Estados Unidos/epidemiologia
20.
Nat Commun ; 13(1): 66, 2022 01 10.
Artigo em Inglês | MEDLINE | ID: mdl-35013187

RESUMO

The Human Silencing Hub (HUSH) complex constituted of TASOR, MPP8 and Periphilin recruits the histone methyl-transferase SETDB1 to spread H3K9me3 repressive marks across genes and transgenes in an integration site-dependent manner. The deposition of these repressive marks leads to heterochromatin formation and inhibits gene expression, but the underlying mechanism is not fully understood. Here, we show that TASOR silencing or HIV-2 Vpx expression, which induces TASOR degradation, increases the accumulation of transcripts derived from the HIV-1 LTR promoter at a post-transcriptional level. Furthermore, using a yeast 2-hybrid screen, we identify new TASOR partners involved in RNA metabolism including the RNA deadenylase CCR4-NOT complex scaffold CNOT1. TASOR and CNOT1 synergistically repress HIV expression from its LTR. Similar to the RNA-induced transcriptional silencing complex found in fission yeast, we show that TASOR interacts with the RNA exosome and RNA Polymerase II, predominantly under its elongating state. Finally, we show that TASOR facilitates the association of RNA degradation proteins with RNA polymerase II and is detected at transcriptional centers. Altogether, we propose that HUSH operates at the transcriptional and post-transcriptional levels to repress HIV proviral expression.


Assuntos
Repressão Epigenética , HIV-2/metabolismo , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Estabilidade de RNA , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Montagem e Desmontagem da Cromatina , Expressão Gênica , Inativação Gênica , Infecções por HIV/virologia , Repetição Terminal Longa de HIV , Células HeLa , Histona-Lisina N-Metiltransferase/genética , Histona-Lisina N-Metiltransferase/metabolismo , Histonas/metabolismo , Humanos , Fosfoproteínas , Provírus/genética , RNA Polimerase II/metabolismo , Schizosaccharomyces
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