Displaying publications 1 - 20 of 123 in total

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  1. Ha CHX, Lee NK, Rahman T, Hwang SS, Yam WK, Chee XW
    J Biomol Struct Dyn, 2023 Apr;41(6):2146-2159.
    PMID: 35067186 DOI: 10.1080/07391102.2022.2028677
    The Human Immunodeficiency Virus (HIV) infection is a global pandemic that has claimed 33 million lives to-date. One of the most efficacious treatments for naïve or pretreated HIV patients is the HIV integrase strand transfer inhibitors (INSTIs). However, given that HIV treatment is life-long, the emergence of HIV strains resistant to INSTIs is an imminent challenge. In this work, we showed two best regression QSAR models that were constructed using a boosted Random Forest algorithm (r2 = 0.998, q210CV = 0.721, q2external_test = 0.754) and a boosted K* algorithm (r2 = 0.987, q210CV = 0.721, q2external_test = 0.758) to predict the pIC50 values of INSTIs. Subsequently, the regression QSAR models were deployed against the Drugbank database for drug repositioning. The top-ranked compounds were further evaluated for their target engagement activity using molecular docking studies and accelerated Molecular Dynamics simulation. Lastly, their potential as INSTIs were also evaluated from our literature search. Our study offers the first example of a large-scale regression QSAR modelling effort for discovering highly active INSTIs to combat HIV infection.Communicated by Ramaswamy H. Sarma.
    Matched MeSH terms: HIV-1*
  2. Tharanga S, Ünlü ES, Hu Y, Sjaugi MF, Çelik MA, Hekimoğlu H, et al.
    Brief Bioinform, 2024 Nov 22;26(1).
    PMID: 39592151 DOI: 10.1093/bib/bbae607
    Sequence diversity is one of the major challenges in the design of diagnostic, prophylactic, and therapeutic interventions against viruses. DiMA is a novel tool that is big data-ready and designed to facilitate the dissection of sequence diversity dynamics for viruses. DiMA stands out from other diversity analysis tools by offering various unique features. DiMA provides a quantitative overview of sequence (DNA/RNA/protein) diversity by use of Shannon's entropy corrected for size bias, applied via a user-defined k-mer sliding window to an input alignment file, and each k-mer position is dissected to various diversity motifs. The motifs are defined based on the probability of distinct sequences at a given k-mer alignment position, whereby an index is the predominant sequence, while all the others are (total) variants to the index. The total variants are sub-classified into the major (most common) variant, minor variants (occurring more than once and of incidence lower than the major), and the unique (singleton) variants. DiMA allows user-defined, sequence metadata enrichment for analyses of the motifs. The application of DiMA was demonstrated for the alignment data of the relatively conserved Spike protein (2,106,985 sequences) of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and the relatively highly diverse pol gene (2637) of the human immunodeficiency virus-1 (HIV-1). The tool is publicly available as a web server (https://dima.bezmialem.edu.tr), as a Python library (via PyPi) and as a command line client (via GitHub).
    Matched MeSH terms: HIV-1/classification; HIV-1/genetics
  3. Yasmin AM
    Med J Malaysia, 1997 Dec;52(4):311-2.
    PMID: 10968105
    Matched MeSH terms: HIV-1/classification*
  4. Cho W, Park S, Kim HJ, Lee M, Choi YS, Yeo SG, et al.
    Rev Med Virol, 2024 Jan;34(1):e2508.
    PMID: 38282393 DOI: 10.1002/rmv.2508
    On 23 July 2022, the World Health Organization declared the global mpox outbreak as a public health emergency of international significance. The mpox virus (MPXV) that caused the outbreak was classified as clade IIb, which belongs to the West African clade. However, the relationship between MPXV clades and symptoms, as well as the severity of mpox outcomes, is not fully understood. Thus, we aimed to investigate the global mpox prevalence and the differences in clinical manifestations and outcomes among patients with mpox between pre-outbreak (2003-2021) and the current mpox outbreak. In this systematic review and meta-analysis, PubMed/MEDLINE, Web of Science, Embase, Cumulative Index to Nursing and Allied Health Literature, and Google Scholar were searched using the keyword "monkeypox" and "mpox" up to 13 October 2022. A random effects model was used to obtain the pooled prevalence and 95% confidence intervals. This study included 27 articles, and 5698 patients with mpox with 19 distinctive features from 19 countries across five continents were assessed. Patients with mpox during the 2022 mpox outbreak showed mild clinical manifestations and outcomes compared with those before the 2022 mpox outbreak: mild rash (relative ratio [RR]: 5.09, 95% confidence interval [CI]: 1.52-17.08), fever (0.68, 0.49-0.94), pruritus (0.25, 0.19-0.32), myalgia (0.50, 0.31-0.81), headache (0.56, 0.35-0.88), skin ulcer (0.32, 0.17-0.59), abdominal symptom (0.29, 0.20-0.42), pharyngitis (0.32, 0.18-0.58), nausea or vomiting (0.15, 0.02-0.93), conjunctivitis (0.11, 0.03-0.38), concomitant infection with HIV (1.70, 0.95-3 0.04), and death (0.02, 0.001-0.31). MPXV clade IIb exhibited higher infectivity but may cause mild disease symptoms and low mortality rate. It is important to consider MPXV infection in patients with mpox-related features and/or a history of sexual transmission to prevent the spread of the disease and recognise the current pandemic threat.
    Matched MeSH terms: HIV-1*
  5. Sugrue E, Wickenhagen A, Mollentze N, Aziz MA, Sreenu VB, Truxa S, et al.
    PLoS Pathog, 2022 Nov;18(11):e1010973.
    PMID: 36399512 DOI: 10.1371/journal.ppat.1010973
    HIV-1 transmission via sexual exposure is an inefficient process. When transmission does occur, newly infected individuals are colonized by the descendants of either a single virion or a very small number of establishing virions. These transmitted founder (TF) viruses are more interferon (IFN)-resistant than chronic control (CC) viruses present 6 months after transmission. To identify the specific molecular defences that make CC viruses more susceptible to the IFN-induced 'antiviral state', we established a single pair of fluorescent TF and CC viruses and used arrayed interferon-stimulated gene (ISG) expression screening to identify candidate antiviral effectors. However, we observed a relatively uniform ISG resistance of transmitted HIV-1, and this directed us to investigate possible underlying mechanisms. Simple simulations, where we varied a single parameter, illustrated that reduced growth rate could possibly underly apparent interferon sensitivity. To examine this possibility, we closely monitored in vitro propagation of a model TF/CC pair (closely matched in replicative fitness) over a targeted range of IFN concentrations. Fitting standard four-parameter logistic growth models, in which experimental variables were regressed against growth rate and carrying capacity, to our in vitro growth curves, further highlighted that small differences in replicative growth rates could recapitulate our in vitro observations. We reasoned that if growth rate underlies apparent interferon resistance, transmitted HIV-1 would be similarly resistant to any growth rate inhibitor. Accordingly, we show that two transmitted founder HIV-1 viruses are relatively resistant to antiretroviral drugs, while their matched chronic control viruses were more sensitive. We propose that, when present, the apparent IFN resistance of transmitted HIV-1 could possibly be explained by enhanced replicative fitness, as opposed to specific resistance to individual IFN-induced defences. However, further work is required to establish how generalisable this mechanism of relative IFN resistance might be.
    Matched MeSH terms: HIV-1*
  6. Tee KK, Kusagawa S, Li XJ, Onogi N, Isogai M, Hase S, et al.
    PLoS One, 2009;4(8):e6666.
    PMID: 19688091 DOI: 10.1371/journal.pone.0006666
    A growing number of emerging HIV-1 recombinants classified as circulating recombinant forms (CRFs) have been identified in Southeast Asia in recent years, establishing a molecular diversity of increasing complexity in the region. Here, we constructed a replication-competent HIV-1 clone for CRF33_01B (designated p05MYKL045.1), a newly identified recombinant comprised of CRF01_AE and subtype B. p05MYKL045.1 was reconstituted by cloning of the near full-length HIV-1 sequence from a newly-diagnosed individual presumably infected heterosexually in Kuala Lumpur, Malaysia. The chimeric clone, which contains the 5' LTR (long terminal repeat) region of p93JP-NH1 (a previously isolated CRF01_AE infectious clone), showed robust viral replication in the human peripheral blood mononuclear cells. This clone demonstrated robust viral propagation and profound syncytium formation in CD4+, CXCR4-expressing human glioma NP-2 cells, indicating that p05MYKL045.1 is a CXCR4-using virus. Viral propagation, however, was not detected in various human T cell lines including MT-2, M8166, Sup-T1, H9, Jurkat, Molt-4 and PM1. p05MYKL045.1 appears to proliferate only in restricted host range, suggesting that unknown viral and/or cellular host factors may play a role in viral infectivity and replication in human T cell lines. Availability of a CRF33_01B molecular clone will be useful in facilitating the development of vaccine candidates that match the HIV-1 strains circulating in Southeast Asia.
    Matched MeSH terms: HIV-1/genetics; HIV-1/isolation & purification*; HIV-1/physiology
  7. Tee KK, Kantor R, Sungkanuparph S, Takebe Y, Li P, Ditangco R, et al.
    J Acquir Immune Defic Syndr, 2015 Sep 01;70(1):e28-30.
    PMID: 25835606 DOI: 10.1097/QAI.0000000000000614
    Matched MeSH terms: HIV-1/classification; HIV-1/genetics; HIV-1/isolation & purification*
  8. SahBandar IN, Takahashi K, Motomura K, Djoerban Z, Firmansyah I, Kitamura K, et al.
    AIDS Res Hum Retroviruses, 2011 Jan;27(1):97-102.
    PMID: 20958201 DOI: 10.1089/aid.2010.0163
    Cocirculation of subtype B and CRF01_AE in Southeast Asia has led to the establishment of new recombinant forms. In our previous study, we found five samples suspected of being recombinants between subtype B and CRF01_AE, and here, we analyzed near full-length sequences of two samples and compared them to known CRFs_01B, subtype B, and CRF01_AE. Five overlapped segments were amplified with nested PCR from PBMC DNA, sequenced, and analyzed for genome mosaicism. The two Indonesian samples, 07IDJKT189 and 07IDJKT194, showed genome-mosaic patterns similar to CRF33_01B references from Malaysia, with one short segment in the 3' end of the p31 integrase-coding region, which was rather more similar to subtype B than CRF01_AE, consisting of unclassified sequences. These results suggest gene-specific continuous diversification and spread of the CRF33_01B genomes in Southeast Asia.
    Matched MeSH terms: HIV-1/classification*; HIV-1/genetics*; HIV-1/isolation & purification
  9. Lau KA, Wang B, Miranda-Saksena M, Boadle R, Kamarulzaman A, Ng KP, et al.
    Curr HIV Res, 2010 Apr;8(3):259-71.
    PMID: 20214658
    In Malaysia, co-circulation of CRF01_AE and subtype B has resulted in the emergence of the second generation derivative; CRF33_01B in approximately 20% of its HIV-1 infected individuals. Our objective was to identify possible biological advantages that CRF33_01B possesses over its progenitors. Biological and molecular comparisons of CRF33_01B against its parental subtypes clearly show that CRF33_01B replicated better in activated whole peripheral blood mononuclear cells (PBMCs) and CD4+ T-lymphocytes, but not monocyte-derived macrophages (MDMs). Also, its acquired fitness was greater than CRF01_AE but not subtype B. Moreover, CRF33_01B has higher rate of apoptotic cell death and syncytia induction compared to subtype B. These adaptive and survival abilities could have been acquired by CRF33_01B due to the incorporation of subtype B fragments into the gag-RT region of its full-length genome. Our studies confirm the previously held belief that HIV-1 strains may harbor enhanced biological fitness upon recombination. We therefore estimate a possible gradual replacement of the current predominance of CRF01_AE, as well as wider dissemination of CRF33_01B, together with the identification of other new CRF01_AE/B inter-subtype recombinants in Malaysia.
    Matched MeSH terms: HIV-1/classification*; HIV-1/genetics; HIV-1/isolation & purification; HIV-1/pathogenicity*
  10. Ng KT, Ng KY, Chen JH, Ng OT, Kamarulzaman A, Tee KK
    Clin Infect Dis, 2014 Sep 15;59(6):910-1.
    PMID: 24944233 DOI: 10.1093/cid/ciu480
    Matched MeSH terms: HIV-1*
  11. Ng KP, He J, Saw TL, Lyles CM
    Med J Malaysia, 2000 Mar;55(1):58-64.
    PMID: 11072492 MyJurnal
    Hepatitis E virus (HEV) is a RNA virus transmitted enterically. A study of anti-HEV antibodies in 145 human immunodeficiency virus type 1 (HIV-1) infected subjects found that 14.4% of them were reactive to anti-HEV antibodies. Anti-HEV IgG and anti-HEV IgM was detected in 10.3% and 4.1% of the subjects respectively. Prevalence of anti-HEV (either IgG or IgM) was similar across all adult ages (p = 0.154), between the three ethnic groups (p = 0.378), and across risk groups (p = 0.120). The results showed that HEV infection in subjects recruited in this study was most likely transmitted via faecal-route.
    Matched MeSH terms: HIV-1*
  12. Mirza MU, Saadabadi A, Vanmeert M, Salo-Ahen OMH, Abdullah I, Claes S, et al.
    Eur J Pharm Sci, 2020 Dec 01;155:105537.
    PMID: 32890663 DOI: 10.1016/j.ejps.2020.105537
    Chemokine receptors are key regulators of cell migration in terms of immunity and inflammation. Among these, CCR5 and CXCR4 play pivotal roles in cancer metastasis and HIV-1 transmission and infection. They act as essential co-receptors for HIV and furnish a route to the cell entry. In particular, inhibition of either CCR5 or CXCR4 leads very often the virus to shift to a more virulent dual-tropic strain. Therefore, dual receptor inhibition might improve the therapeutic strategies against HIV. In this study, we aimed to discover selective CCR5, CXCR4, and dual CCR5/CXCR4 antagonists using both receptor- and ligand-based computational methods. We employed this approach to fully incorporate the interaction attributes of the binding pocket together with molecular dynamics (MD) simulations and binding free energy calculations. The best hits were evaluated for their anti-HIV-1 activity against CXCR4- and CCR5-specific NL4.3 and BaL strains. Moreover, the Ca2+ mobilization assay was used to evaluate their antagonistic activity. From the 27 tested compounds, three were identified as inhibitors: compounds 27 (CCR5), 6 (CXCR4) and 3 (dual) with IC50 values ranging from 10.64 to 64.56 μM. The binding mode analysis suggests that the active compounds form a salt bridge with the glutamates and π-stacking interactions with the aromatic side chains binding site residues of the respective co-receptor. The presented hierarchical virtual screening approach provides essential aspects in identifying potential antagonists in terms of selectivity against a specific co-receptor. The compounds having multiple heterocyclic nitrogen atoms proved to be relatively more specific towards CXCR4 inhibition as compared to CCR5. The identified compounds serve as a starting point for further development of HIV entry inhibitors through synthesis and quantitative structure-activity relationship studies.
    Matched MeSH terms: HIV-1*
  13. Sivakumar I, Arunachalam S, Choudhary S, Mahmoud-Buzayan M, Tawfiq O, Sharan J
    AIDS Rev, 2020;22(1):3-8.
    PMID: 32167505 DOI: 10.24875/AIDSRev.20000107
    HIV infection is a global pandemic that affects CD4 cells in the immune system and leads to lethal opportunistic infections. The advent of highly active antiretroviral therapy (HAART) has induced a marked reduction in the viral load and an increase in the CD4 cell count, thereby changing the course of the disease from an acute life-threatening condition to chronic disease. Accordingly, need and demand for oral rehabilitation in HIV positive population have increased in recent years. However, few drugs used in the HAART regimen have also known to be associated with osteopenia and osteoporosis. Although HAART reduces the morbidity in HIV patients, it remains unknown to what extent the therapy influences the implant healing. Few scientific literatures have identified osteoporosis and HIV infection as an unconducive milieu for dental implant placement and survival but demonstrated favorable outcomes in short-term assessments. The long-term impact of bone metabolic effects of HAART on implant success remains a conundrum.
    Matched MeSH terms: HIV-1*
  14. Cheng PG, Teoh TC, Rizman-Idid M
    Int J Med Mushrooms, 2021;23(7):63-77.
    PMID: 34375519 DOI: 10.1615/IntJMedMushrooms.2021038682
    In this study, crude extracts of Ganoderma lucidum (NGCs) were compared to the crude extracts of G. lucidum that has antler-like fruiting bodies (AGCs) for their cytotoxicity, inhibitory effects on the attachment of human immunodeficiency virus (HIV)-1 glycoprotein 120 (gp120) to cluster of differentiation 4 (CD4), identification and molecular docking simulations of chemical compounds to predict the best ligand inhibitor and the binding mechanism. Results showed that AGCs had a higher percentage of inhibition (54.3% ± 6.2%) at 150 ppm and higher cytotoxicity (half maximal cytotoxic concentration [CC50] < 300 ppm) than NGCs (CC50 < 400 ppm). Quadrupole time-of-flight (QTOF) liquid chromatography- mass spectrometry (LC-MS) results successfully identified 32 chemical compounds in AGCs and NGCs, comprising mostly ganoderic acids (62%) and their derivatives. Molecular docking simulations of ganolucidic acid A/D and ganoderic acid A/B predicted the strongest binding affinity via hydrogen bonding, suggesting the inhibition of HIV-1 gp120 attachment to CD4. The highest and lowest occupied molecular orbital (HOMO and LUMO, respectively) gap energies of ganoderic acids tended to have less negative HOMO energy and smaller HOMO-LUMO gap energy, implying increased interactions of ligands to the gp120 protein receptor. AGCs showed higher inhibition against HIV-1 gp120 than NGCs due to a higher abundance of ganoderic and ganolucidic acids, whereby both acids contributed the highest number of hydrogen bonds and polar interactions from the hydroxyl and carboxylic functional groups.
    Matched MeSH terms: HIV-1*
  15. Han F, Gulam MY, Zheng Y, Zulhaimi NS, Sia WR, He D, et al.
    Front Immunol, 2022;13:985385.
    PMID: 36341446 DOI: 10.3389/fimmu.2022.985385
    MAIT cells are persistently depleted and functionally exhausted in HIV-1-infected patients despite long-term combination antiretroviral therapy (cART). IL-7 treatment supports MAIT cell reconstitution in vivo HIV-1-infected individuals and rescues their functionality in vitro. Single-nucleotide polymorphisms (SNPs) of the IL-7RA gene modulate the levels of soluble(s)IL-7Rα (sCD127) levels and influence bioavailability of circulating IL-7. Here we evaluate the potential influence of IL-7RA polymorphisms on MAIT cell numbers and function in healthy control (HC) subjects and HIV-1-infected individuals on long-term cART. Our findings indicate that IL-7RA haplotype 2 (H2*T), defined as T-allele carriers at the tagging SNP rs6897932, affects the size of the peripheral blood MAIT cell pool, as well as their production of cytokines and cytolytic effector proteins in response to bacterial stimulation. H2*T carriers had lower sIL-7Rα levels and higher MAIT cell frequency with enhanced functionality linked to higher expression of MAIT cell-associated transcription factors. Despite an average of 7 years on suppressive cART, MAIT cell levels and function in HIV-1-infected individuals were still significantly lower than those of HC. Notably, we observed a significant correlation between MAIT cell levels and cART duration only in HIV-1-infected individuals carrying IL-7RA haplotype 2. Interestingly, treatment with sIL-7Rα in vitro suppressed IL-7-dependent MAIT cell proliferation and function following cognate stimulations. These observations suggest that sIL-7Rα levels may influence MAIT cell numbers and function in vivo by limiting IL-7 bioavailability to MAIT cells. Collectively, these observations suggest that IL-7RA polymorphisms may play a significant role in MAIT cell biology and influence MAIT cells recovery in HIV-1 infection. The potential links between IL7RA polymorphisms, MAIT cell immunobiology, and HIV-1 infection warrant further studies going forward.
    Matched MeSH terms: HIV-1*
  16. Saeidi A, Ellegård R, Yong YK, Tan HY, Velu V, Ussher JE, et al.
    J Leukoc Biol, 2016 08;100(2):305-14.
    PMID: 27256572 DOI: 10.1189/jlb.4RU0216-084R
    MAIT cells represent an evolutionarily conserved, MR1-restricted, innate-like cell subset that express high levels of CD161; have a canonical semi-invariant TCR iVα7.2; and may have an important role in mucosal immunity against various bacterial and fungal pathogens. Mature MAIT cells are CD161(hi)PLZF(hi)IL-18Rα(+)iVα7.2(+)γδ-CD3(+)CD8(+) T cells and occur in the peripheral blood, liver, and mucosa of humans. MAIT cells are activated by a metabolic precursor of riboflavin synthesis presented by MR1 and, therefore, respond to many bacteria and some fungi. Despite their broad antibacterial properties, their functional role in persistent viral infections is poorly understood. Although there is an increasing line of evidence portraying the depletion of MAIT cells in HIV disease, the magnitude and the potential mechanisms underlying such depletion remain unclear. Recent studies suggest that MAIT cells are vulnerable to immune exhaustion as a consequence of HIV and hepatitis C virus infections and HIV/tuberculosis coinfections. HIV infection also appears to cause functional depletion of MAIT cells resulting from abnormal expression of T-bet and EOMES, and effective ART is unable to completely salvage functional MAIT cell loss. Depletion and exhaustion of peripheral MAIT cells may affect mucosal immunity and could increase susceptibility to opportunistic infections during HIV infection. Here, we review some of the important mechanisms associated with depletion and functional loss of MAIT cells and also suggest potential immunotherapeutic strategies to restore MAIT cell functions, including the use of IL-7 to restore effector functions in HIV disease.
    Matched MeSH terms: HIV-1/immunology*
  17. Azzman N, Gill MSA, Hassan SS, Christ F, Debyser Z, Mohamed WAS, et al.
    Rev Med Virol, 2024 Mar;34(2):e2529.
    PMID: 38520650 DOI: 10.1002/rmv.2529
    The discovery of anti-retroviral (ARV) drugs over the past 36 years has introduced various classes, including nucleoside/nucleotide reverse transcriptase inhibitors, non-nucleoside reverse transcriptase inhibitors, protease inhibitor, fusion, and integrase strand transfer inhibitors inhibitors. The introduction of combined highly active anti-retroviral therapies in 1996 was later proven to combat further ARV drug resistance along with enhancing human immunodeficiency virus (HIV) suppression. As though the development of ARV therapies was continuously expanding, the variation of action caused by ARV drugs, along with its current updates, was not comprehensively discussed, particularly for HIV-1 infection. Thus, a range of HIV-1 ARV medications is covered in this review, including new developments in ARV therapy based on the drug's mechanism of action, the challenges related to HIV-1, and the need for combination therapy. Optimistically, this article will consolidate the overall updates of HIV-1 ARV treatments and conclude the significance of HIV-1-related pharmacotherapy research to combat the global threat of HIV infection.
    Matched MeSH terms: HIV-1*
  18. Jiamsakul A, Chaiwarith R, Durier N, Sirivichayakul S, Kiertiburanakul S, Van Den Eede P, et al.
    J Med Virol, 2016 Feb;88(2):234-43.
    PMID: 26147742 DOI: 10.1002/jmv.24320
    HIV drug resistance assessments and interpretations can be obtained from genotyping (GT), virtual phenotyping (VP) and laboratory-based phenotyping (PT). We compared resistance calls obtained from GT and VP with those from PT (GT-PT and VP-PT) among CRF01_AE and subtype B HIV-1 infected patients. GT predictions were obtained from the Stanford HIV database. VP and PT were obtained from Janssen Diagnostics BVBA's vircoType(TM) HIV-1 and Antivirogram®, respectively. With PT assumed as the "gold standard," the area under the curve (AUC) and the Bland-Altman plot were used to assess the level of agreement in resistance interpretations. A total of 80 CRF01_AE samples from Asia and 100 subtype B from Janssen Diagnostics BVBA's database were analysed. CRF01_AE showed discordances ranging from 3 to 27 samples for GT-PT and 1 to 20 samples for VP-PT. The GT-PT and VP-PT AUCs were 0.76-0.97 and 0.81-0.99, respectively. Subtype B showed 3-61 discordances for GT-PT and 2-75 discordances for VP-PT. The AUCs ranged from 0.55 to 0.95 for GT-PT and 0.55 to 0.97 for VP-PT. Didanosine had the highest proportion of discordances and/or AUC in all comparisons. The patient with the largest didanosine FC difference in each subtype harboured Q151M mutation. Overall, GT and VP predictions for CRF01_AE performed significantly better than subtype B for three NRTIs. Although discrepancies exist, GT and VP resistance interpretations in HIV-1 CRF01_AE strains were highly robust in comparison with the gold-standard PT.
    Matched MeSH terms: HIV-1/drug effects*; HIV-1/genetics*; HIV-1/isolation & purification
  19. Hora B, Keating SM, Chen Y, Sanchez AM, Sabino E, Hunt G, et al.
    PLoS One, 2016;11(6):e0157340.
    PMID: 27314585 DOI: 10.1371/journal.pone.0157340
    HIV-1 subtypes and drug resistance are routinely tested by many international surveillance groups. However, results from different sites often vary. A systematic comparison of results from multiple sites is needed to determine whether a standardized protocol is required for consistent and accurate data analysis. A panel of well-characterized HIV-1 isolates (N = 50) from the External Quality Assurance Program Oversight Laboratory (EQAPOL) was assembled for evaluation at seven international sites. This virus panel included seven subtypes, six circulating recombinant forms (CRFs), nine unique recombinant forms (URFs) and three group O viruses. Seven viruses contained 10 major drug resistance mutations (DRMs). HIV-1 isolates were prepared at a concentration of 107 copies/ml and compiled into blinded panels. Subtypes and DRMs were determined with partial or full pol gene sequences by conventional Sanger sequencing and/or Next Generation Sequencing (NGS). Subtype and DRM results were reported and decoded for comparison with full-length genome sequences generated by EQAPOL. The partial pol gene was amplified by RT-PCR and sequenced for 89.4%-100% of group M viruses at six sites. Subtyping results of majority of the viruses (83%-97.9%) were correctly determined for the partial pol sequences. All 10 major DRMs in seven isolates were detected at these six sites. The complete pol gene sequence was also obtained by NGS at one site. However, this method missed six group M viruses and sequences contained host chromosome fragments. Three group O viruses were only characterized with additional group O-specific RT-PCR primers employed by one site. These results indicate that PCR protocols and subtyping tools should be standardized to efficiently amplify diverse viruses and more consistently assign virus genotypes, which is critical for accurate global subtype and drug resistance surveillance. Targeted NGS analysis of partial pol sequences can serve as an alternative approach, especially for detection of low-abundance DRMs.
    Matched MeSH terms: HIV-1/drug effects; HIV-1/genetics*; HIV-1/pathogenicity
  20. Lau KA, Wang B, Kamarulzaman A, Ngb KP, Saksena NK
    Curr HIV Res, 2008 Mar;6(2):108-16.
    PMID: 18336258
    The Asian HIV epidemic appears to be complex, characterized by the prevalence of multiple subtypes and circulating recombinant forms with gradual replacement of pure HIV-1 subtypes in several geographical regions. The main objectives of the present study are to identify and analyse the full-length viral genomes of three unique recombinant forms (URFs); the HIV-1 isolates 07MYKLD47, 07MYKLD48 and 07MYKLD49 from Malaysia. Long-range polymerase chain reaction (PCR) amplification of seven overlapping reading frames was used to derive near full-length HIV-1 genomes. Detailed phylogenetic and bootscanning analyses were performed to determine phylogenetic associations and subtypic assignments. We further confirmed the mosaic composition of these CRF01_AE/B inter-subtype recombinant forms, which are composed of B-subtype fragment(s) in the backbone of CRF01_AE. Both 07MYKLD47 and 07MYKLD48 have an insertion of B subtype (880 bp and 532 bp) in the gag-pol and gp41-env gene regions, respectively. Whereas the isolate 07MYKLD49 has three B-subtype fragments inserted in different gene region along the genome; one each in the gag-pol (1862 bp) and pol-vif (1935 bp) regions, and a short B-subtype insertion (541 bp) in the 5' LTR-gag region. This highlights the public health relevance of newly emerging second generation HIV-1 recombinant forms and their dispersal, along with their rapid and continuous evolution in the region.
    Matched MeSH terms: HIV-1/classification*; HIV-1/genetics*; HIV-1/isolation & purification
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