• Journal of Life Science
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• v.15 no.2 s.69
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• pp.186-191
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• 2005

Previous studies have demonstrated that expression of galectin-3, a member of family of beta-galactoside-binding animal lectin, is associated with pathological conditions including cancer, atherosclerosis, and viral infection. An increase of this lectin has been observed after infection by Kirsten murine sarcoma, human T lymphotropic virus-l (HTLV-l), and human immunodeficiency virus-l (HIV-l). Viral transactivation protein Tax of HTLV-l mediates the increase in the lectin. In case of HIV-1, there are evidences that Tat would be related with increase in galectin-3. We investigated whether Tat directly induced galectin-3 expression in cells. We found that HIV-l tat gene activated galectin-3 promoter in RAW264.7 cells. To demonstrate direct induction of galectin-3 by HIV-l tat, we transfected the tat into a rabbit smooth muscle cell line (Rb1) and obtained RblTatCl-2, a clone of cell stably transfected with tat gene. The Rb1TatCl-2 cells exhibited activation of LTR promoter and up-regulation of galectin-3 transcript as well as protein. Our results indicate that HIV-l tat alone is sufficient to induce the expression of galectin-3. The Rb1TatCl-2 cells could be valuable for study of the effect of HIV-1 tat on expression of cellular genes.

• Journal of Microbiology and Biotechnology
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• v.10 no.6
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• pp.797-804
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• 2000

The human immunodeficiency virus type 1 (HIV-1) Tat is one of the viral gene products essential for HIV replication. The exogenous Tat protein is transduced through the plasma membrane and then accumulated in a cell. The basic domain of the Tat protein, which is rich in arginine and lysine residues and called the protein transduction domain (PTD), has been identified to be responsible for this transduction activity. To better understand the nature of the transduction mediated by this highly basic domain of HIV-1 Tat, the Green Fluorescent Protein (GFP) was expressed and purified as a fusion protein with a peptide derived from the HIV-1 Tat basic domain in Escherichia coli. The transduction of Tat-GFP into mammalian cells was then determined by a Western blot analysis and fluorescence microscopy. The cells treated with Tat-GFP exhibited dose- and time-dependent increases in their intracellular level of the protein. the effective transduction of denatured Tat-GFP into both the nucleus and the cytoplasm of mammalian cells was also demonstrated, thereby indicating that the unfolding of the transduced protein is required for efficient transduction. Accordingly, the availability of recombinant Tat-GFP can facilitate the simple and specific identification of the protein transduction mediated by the HIV-1 Tat basic domain in living cells either by fluorescence microscopy or by a fluorescence-activated cell sorter analysis.

• Tuberculosis and Respiratory Diseases
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• v.81 no.1
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• pp.59-72
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• 2018

Background: It remains uncertain if $interferon-{\gamma}$ release assays (IGRAs) are superior to the tuberculin skin test (TST) for the diagnosis of active tuberculosis (TB) or latent tuberculosis infection (LTBI) in immunosuppressed populations including people with human immunodeficiency virus (HIV) infection. The purpose of this study was to systematically review the performance of IGRAs and the TST in people with HIV with active TB or LTBI in low and high prevalence TB countries. Methods: We searched the MEDLINE database from 1966 through to January 2017 for studies that compared results of the TST with either the commercial QuantiFERON-TB Gold in Tube (QFTGT) assay or previous assay versions, the T-SPOT.TB assay or in-house IGRAs. Data were summarized by TB prevalence. Tests for concordance and differences in proportions were undertaken as appropriate. The variation in study methodology was appraised. Results: Thirty-two studies including 4,856 HIV subjects met the search criteria. Fourteen studies compared the tests in subjects with LTBI in low TB prevalence settings. The QFTGT had a similar rate of reactivity to the TST, although the first-generation version of that assay was reactive more commonly. IGRAs were more frequently positive than the TST in HIV infected subjects with active TB. There was considerable study methodology and population heterogeneity, and generally low concordance between tests. Both the TST and IGRAs were affected by CD4 T-cell immunodeficiency. Conclusion: Our review of comparative data does not provide robust evidence to support the assertion that the IGRAs are superior to the TST when used in HIV infected subjects to diagnose either active TB or LTBI.

• Bulletin of the Korean Chemical Society
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• v.34 no.8
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• pp.2466-2472
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• 2013

Human immunodeficiency virus type-1 (HIV-1) is a causative agent of Acquired immunodeficiency syndrome (AIDS), which has affected a large population of the world. Viral envelope glycoprotein (gp120) is an intrinsic protein for HIV-1 to enter into human host cells. Molecular docking guided molecular dynamics (MD) simulation was performed to explore the interaction mechanism of heterobiaryl derivative with gp120. MD simulation result of inhibitor-gp120 complex demonstrated stability. Our MD simulation results are consistent with most of the previous mutational and modeling studies. Inhibitor has an interaction with the CD4 binding region. Van der Waals interaction between inhibitor and Val255, Thr257, Asn425, Met426 and Trp427 were important. This preliminary MD model could be useful in exploiting heterobiaryl-gp120 interaction in greater detail, and will likely to shed lights for further utilization in the development of more potent inhibitors.

• The Journal of Korean Society of Virology
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• v.27 no.1
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• pp.69-75
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• 1997

To evaluate in vitro anti-HIV efficacies of nucleoside derivatives, MT-4 cell line was infected with HIV-1 and HIV-2 respectively and treated with various compounds and the formerly approved drugs such as AZT, d4T, ddC and ddI. CPE method was used to evaluate their antiviral activity. Most dideoxynucleosides, AZT, d4T, ddC and ddI, showed anti-HIV activities against both viruses but no other compounds including anti-herpesvirus drugs did any. Further experiments were carried out to study their inhibitory mechanism of viral adsorption. The results showed no inhibition of syncytium formation due to an interaction between the gp120 expressed in HIV -infected cell surface and CD4 receptor on the uninfected cell surface in the presence of AZT. AZT showed no activity up to $100\;{\mu}g/ml$. Inhibition of reverse transcriptase (RT) in the presence of AZT-triphosphate was tested by using RT expressed in E. coli and purified and its $IC_{50}$ was 4.5 nM.

• Bulletin of the Korean Chemical Society
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• v.25 no.7
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• pp.991-996
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• 2004

New series of 6-(arylthio)uracils, 6-(4-substituted-1-piperazinyl)uracils, 2,4,5-trioxo-1H,3H-benzothiopyrano[2,3-d]pyrimidine and 5-aryl-2,4-dioxo-1H,3H-pyrimido[5,4-f]benzo[1,4]thiazepines have been prepared and screened for their in vitro activity against herpes simplex-1 virus (HSV-1) and human immunodeficiency virus-1 (HIV-1). The in vitro cytotoxic activity was also evaluated. The results of biological testing revealed that compound 5b showed marginal activity against HSV-1, while compounds 5b and 5f exhibited marginal activity against HIV-1. The rest of the tested compounds were found devoid of antiviral activity against both HSV-1 and HIV-1.

• Journal of Microbiology and Biotechnology
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• v.18 no.6
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• pp.1044-1049
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• 2008

In order to study functional nucleotides in prototype foamy virus (PFV) DNA on specific recognition by PFV integrase (IN), we designed chimeric U5 long terminal repeat (LTR) DNA substrates by exchanging comparative sequences between human immunodeficiency virus type-1 (HIV-1) and PFV U5 LTRs, and investigated the 3'-end processing reactivity using HIV-1 and PFV INs, respectively. HIV-1 IN recognized the nucleotides present in the fifth and sixth positions at the 3'-end of the substrates more specifically than any other nucleotides in the viral DNA. However, PFV IN recognized the eighth and ninth nucleotides as distinctively as the fifth and sixth nucleotides in the reactions. In addition, none of the nucleotides present in the twelfth, sixteenth, seventeenth, eighteenth, nineteenth, and twentieth positions were not differentially recognized by HIV-1 and PFV INs, respectively. Therefore, our results suggest that the functional nucleotides that are specifically recognized by its own IN in the PFV U5 LTR are different from those in the HIV-1 U5 LTR in aspects of the positions and nucleotide sequences. Furthermore, it is proposed that the functional nucleotides related to the specific recognition by retroviral INs are present inside ten nucleotides from the 3'-end of the U5 LTR.

• Biomolecules & Therapeutics
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• v.3 no.3
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• pp.210-216
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• 1995

Partially purified water-soluble extract mixture from Ricini and Coptidis (named as RIC) showed to be a potent inhibitor of human immunodeficiency virus-1 (HIV-1) replication. RIC was evaluated for in vitro anti-HIV activity using SupTl and H9 cells infected by a recombinant virus (pSVCAT) containing chloramphenicol acetyltransferase (CAT) gene substituted for nef gene in the HIV-1 genome. RIC inhibited syncytiaformation of SupTl cells with a half maximal effective concentration, $IC_{50}$/, of 2.5 $\mu\textrm{g}$/mι and showed marked inhibition of CAT activity in the infected H9 cells and also suppressed reverse transcriptase (RT) activity in the supernatant of the infected H9 culture. However, RIC did not inhibit the activity of reverse transcriptase directly when it was mixed with the enzyme or with viral particles. Berberine, one of components of RIC, also showed similar anti-HIV activity as RIC did. The data suggest that there are active ingredients which mediate anti-HIV activity in RIC.

• BMB Reports
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• v.51 no.7
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• pp.338-343
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• 2018

Transcription termination factor-1 (TTF-I) is an RNA polymerase 1-mediated transcription terminator and consisting of a C-terminal DNA-binding domain, central domain, and N-terminal regulatory domain. This protein binds to a so-called 'Sal box' composed of an 11-base pair motif. The interaction of TTF-I with the 'Sal box' is important for many cellular events, including efficient termination of RNA polymerase-1 activity involved in pre-rRNA synthesis and formation of a chromatin loop. To further understand the role of TTF-I in human immunodeficiency virus (HIV)-I virus production, we generated various TTF-I mutant forms. Through a series of studies of the over-expression of TTF-I and its derivatives along with co-transfection with either proviral DNA or HIV-I long terminal repeat (LTR)-driven reporter vectors, we determined that wild-type TTF-I downregulates HIV-I LTR activity and virus production, while the TTF-I Myb-like domain alone upregulated virus production, suggesting that wild-type TTF-I inhibits virus production and trans-activation of the LTR sequence; the Myb-like domain of TTF-I increased virus production and trans-activated LTR activity.

• Korean Journal of Oriental Medicine
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• v.10 no.1
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• pp.119-126
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• 2004

For the purpose of developing new anti-HIV agents from natural sources, the extracts of Solanum nigrum L. were tested for their inhibitory effects on HIV-1 replication and its essential enzymes as the reverse transcriptase (RT), protease and ${\alpha}$-glucosidase. In the assay of HIV-1-infected human T-cell line, water extracts inhibited the HIV- 1 -induced cytopathic effects with IC (inhibitory concentration) of 100 ug/ml. Moreover water extracts (100ug/ml) of aerial parts showed strong activity of 32.6% on anti-HIV-1 PR using the activity of the enzyme to cleave an oligopeptide. In the HIV-1 reverse transcriptase inhibition assay, aqueous extract a inhibited 17.4%, but no glucosidase inhibitory activities. We found out this result, for these samples it is possible that the inhibition of the viral replication in vitro is due to the inhibition at least one of PR and RT. It would be of great interest to identify the compounds which are responsible for this inhibition, since all therapeutically useful agent up to date are PR, RT and ${\alpha}$-glucosidase inhibitors.