Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0021051 (immunodeficiency)
 71,517 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Maleylated-human serum albumin (Mal-HSA) inhibited human immunodeficiency virus type-1 (HIV-1) infection of MT-4 cells in vitro. It was also found to inhibit the fusion between uninfected CD4+ cells (Molt-4 clone 8 cells) and HIV-1 infected cells (Molt-4/HIV-1) to form syncytia. To investigate the mechanism of the inhibition, a study was designed to determine whether Mal-HSA could bind to CD4+ cells. Mal-HSA could bind to both MT-4 cells and Molt-4 clone 8 cells with high affinity, Kd = 2.0 nM and Kd = 5.8 nM, respectively. However, Mal-HSA could neither inhibit anti CD4 antibody Leu 3a binding to Molt-4 clone 8 cells nor modulate the expression of CD4 molecules on the surface of the cells. Mal-HSA binding to Molt-4 clone 8 cells was completely inhibited by sulfated polysaccharides bearing anti-HIV activity, such as dextran sulfate, fucoidan and carrageenan. Other HIV-1 susceptible human T-cell lines, such as Molt-4, CEM-5, H-9 and HuT-78 cells, also have Mal-HSA binding sites showing a high affinity, Kd = 0.9 +/- 0.4 nM. Mal-HSA binding proteins of Molt-4 clone 8 cells were identified by ligand blotting as 155 and 220 kDa proteins. Unlike dextran sulfate, Mal-HSA could not inhibit reverse transcriptase activity of HIV-1. These results indicate that Mal-HSA inhibits HIV-1 infection and syncytia formation, and suggest that 155 and/or 220 kDa proteins of target cells are involved in HIV-1 adsorption and/or the membrane fusion between HIV-1 and target cells.
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PMID:Maleylated human serum albumin inhibits HIV-1 infection in vitro. 128 31

A synthesis scheme for 3'-C-methyl-2'-deoxynucleosides and 3'-C-methylidene-2',3'-dideoxy-5-methyluridine has been proposed with 2-deoxyribose as the starting material. Methyl 5-O-benzoyl-2-deoxyribofuranose was oxidized and the mixture of the 3'-keto derivatives was separated into the alpha- and beta-anomers. The beta-keto derivative was converted by reaction with MeMgBr, and after reaction with thymine and subsequent deprotection 1-(3'-C-methyl-2'-alpha-deoxy-alpha-D-threo-pentofuranosyl)thymine and its beta-anomer were obtained. The same reactions with the alpha-keto sugar gave 1-(3'-C-methyl-2'-deoxy-alpha-D-erythro-pentofuranosyl)thymine and its beta-anomer. 1-(5-O-Benzoyl-3'-C-methyl-2'-deoxy-alpha-D-threo-pentofuranosyl)thymine was converted to a mixture of 3'-C-methylidene-2',3'-dideoxy-5-methyluridine and 3'-C-methyl-2',3'-dideoxy-2',3'-didehydro-5-methyluridine, which were separated. The stereoselectivity of the Grignard reagent's attachment to 2-deoxyfuranose 3-ulosides has been ruled by the substitute configuration at Cl. Also, the effect of the hydroxyl or OBz group configuration at C3 on the condensation stereoselectivity of 3-C-methyl-2-deoxyfuranosides with silylated thymine has been studied. The structure of the obtained compounds was proved by 1H NMR UV, 13C NMR, and CD spectroscopy, as well as elemental (C, H, N) analysis. The C2'-endo-C1'-exo conformation, the anti conformation of thymine in relation to the glycosidic bond, and the gauche+conformation in relation to the C4'-C5' bond are characteristic for the 3'-C-methyl-2'-deoxythymidine structure in the crystals. 3'-C-Methyl-2'-deoxythymidine 5'-triphosphate was synthesized and proved to be a competitive inhibitor, with respect to dTTP, of a number of DNA polymerases, including the reverse transcriptases of human immunodeficiency virus type 1 (HIV-1) and avian myeloblastosis virus (AMV). None of the DNA polymerases examined were able to incorporate this compound into the growing DNA chain. In contrast, 3'-C-methylidene-2',3'-dideoxy-5-methyluridine 5'-triphosphate was found to be incorporated at the 3'-end of the DNA chain by HIV-1 reverse transcriptase, albeit with very low efficiency. 3'-C-Methyl-2'-deoxy-5-methyluridine did not suppress HIV-1 replication in MT-4 cells at 500 microM while its 5'-phosphite derivative exhibited modest anti-HIV-1 activity.
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PMID:3'-C-branched 2'-deoxy-5-methyluridines: synthesis, enzyme inhibition, and antiviral properties. 128 82

The drug Ro5-3335 [7-chloro-5-(2-pyrryl)-3H-1,4-benzodiazepin-2(H)-one] inhibits human immunodeficiency virus type 1 (HIV-1) gene expression at the transcriptional level through interference with Tat-mediated transactivation (M.-C. Hsu, A. D. Schutt, M. Holly, L. W. Slice, M. I. Sherman, D. D. Richman, M. J. Potash, and D. J. Volsky, Science 254:1799-1802, 1991). We confirmed this specific inhibitory effect in a quantitative bioassay based on transactivation of a chimeric gene comprising the HIV-1 long terminal repeat promoter fused to the lacZ gene of Escherichia coli and transfected in a HeLa cell line expressing Tat. Ro5-3335 was found to inhibit HIV-1 long terminal repeat-driven lacZ gene expression at a 50% inhibitory concentration of 0.5 microM. The in vitro anti-HIV-1 activity of Ro5-3335 was highly dependent on the nature of the host cells. The highest selectivity index, 50, was found in phytohemagglutinin-stimulated peripheral blood lymphocytes. The selectivity index was between 1 and 10 in the CD4+ T-cell lines CEM, MOLT-4 (clone 8), and HUT-78. In MT-4 and MT-2 cells, Ro5-3335 had no inhibitory effect on HIV-1 replication. The absence of anti-HIV-1 activity of Ro5-3335 in MT-4 cells was confirmed by using different parameters of virus replication and different multiplicities of infection. In persistently HIV-1-infected HUT-78/IIIB/LAI cells, Ro5-3335 failed to demonstrate any activity at subtoxic concentrations. The cytotoxicity of Ro5-3335 was significantly lower in peripheral blood lymphocytes than in the CD4+ T-cell lines.
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PMID:Cell type-specific anti-human immunodeficiency virus type 1 activity of the transactivation inhibitor Ro5-3335. 128 90

An aqueous extract of Phyllanthus niruri (Euphorbiaceae) inhibited human immunodeficiency virus type-1 reverse transcriptase (HIV-1-RT). The inhibitor against HIV-1-RT in this plant was purified by combination of three column chromatographies, Sephadex LH-20, cellulose, and reverse-phase high-performance liquid chromatography. The inhibitor was then identified by nuclear magnetic resonance (NMR) spectra as repandusinic acid A monosodium salt (RA) which was originally isolated from Mallotus repandus. The 50% inhibitory doses (ID50) of RA on HIV-1-RT and DNA polymerase alpha (from HeLa cells) were 0.05 microM and 0.6 microM, respectively, representing approximately a 10-fold more sensitivity of HIV-1-RT compared with DNA polymerase alpha. RA was shown to be a competitive inhibitor with respect to the template-primer while it was a noncompetitive inhibitor with respect to the substrate. RA as low as 10.1 microM inhibited HIV-1-induced cytopathogenicity in MT-4 cells. In addition, 4.5 microM of RA inhibited HIV-1-induced giant cell formation of SUP-T1 approximately 50%. RA (2.5 microM) inhibited up to 90% of HIV-1 specific p24 antigen production in a Clone H9 cell system.
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PMID:HIV-1 reverse transcriptase inhibitor from Phyllanthus niruri. 128 10

In vitro infectivity of the MT4 lymphoid cell line with human immunodeficiency virus (HIV) has been studied in correlation with the degree of expression of the CD4 molecule at the cell surface. To modulate this CD4 expression in vitro, pre-incubation with phorbol myristate acetate (PMA) was used. The lowest CD4 expression was obtained after 1 to 5 hours. Thereafter, a partial re-expression of OKT4 was observed, e.g., when the incubation time with PMA was extended to 20 hours. Reverse transcriptase (RT) activity decreased and was delayed proportionally to the length of incubation of cells with PMA. This observation was confirmed by the comparable variation of cytopathic effects and of p24 antigen release in culture supernatants. The decrease in HIV infectivity hence correlated with that of OKT4 expression when PMA treatment did not exceed a few hours. By contrast, after extended treatment, infectivity remained decreased although OKT4 expression reappeared.
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PMID:Phorbol ester induces down-regulation of CD4 molecule expression and resistance to in vitro infection by HIV1. 128 70

1-beta-D-Arabinofuranosyl-E-5-(2-bromovinyl)uracil (BV-araU) and E-5-(2-bromovinyl)uracil, a metabolite of BV-araU, did not affect either the anti-human immunodeficiency virus activity or the cytotoxicity of azidothymidine in MT-4 and MOLT-4 cells. Similarly, the bromovinyl compounds did not affect the in vitro antitumor activities of arabinosylcytosine, 5-fluorouracil, and 5-fluoro-2'-deoxyuridine. The anti-varicella-zoster virus activity of BV-araU was not influenced by azidothymidine, 2',3'-didehydro-2',3'-dideoxythymidine, or arabinosylcytosine, whereas relatively high concentrations of fluorinated antitumor agents enhanced the anti-varicella-zoster virus activity.
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PMID:In vitro drug combination of 1-beta-D-arabinofuranosyl-E-5-(2-bromovinyl)uracil with anti-human immunodeficiency virus or anticancer nucleosides. 131 47

Starting from 3-O-mesyl-1,2-O-isopropylidene-alpha-D-allofuranose (9) the anomeric mixtures of the requisite carbohydrates 1,2-di-O-acetyl-6-O-benzoyl-5-deoxy-3-O-mesyl-D-allofuranoses++ + 17A alpha/beta, 1,2-di-O-acetyl-5,6-di-O-benzoyl-3-O-mesyl-D-allofuranoses 17B alpha/beta, and 1,2-di-O-acetyl-5,6-di-O-benzoyl-3-O-mesyl-L-talofuranoses 17C alpha/beta were synthesized. 1,2-Di-O-acetyl-5-O-benzoyl-6-deoxy-3-O-mesyl-D-allofuranoses++ + 17D alpha/beta and the corresponding L-talofuranoses 17E alpha/beta were obtained from 6-deoxy-3,5-di-O-benzoyl-1,2-O-isopropylidene-alpha-D- allofuranose (12) and the corresponding beta-L-talofuranose 13. Coupling of these sugar derivatives with thymine gave the beta-nucleoside derivatives 18A-E. Treatment of compounds 18A-E with DBU produced the corresponding 2,3'-anhydro nucleosides 19A-E with a free 2'-OH group. After deoxygenation of 2'-O-[[(4-methylphenyl)oxy]thiocarbonyl] compounds 20A-E with tributyltin hydride the 2,3'-anhydro bridge of the 2'-deoxynucleosides 21A-E was opened with LiN3 to produce the protected 3'-azido-2,3'-dideoxynucleoside derivatives 22A-G. Saponification with NaOCH3 gave 1-(3'-azido-2',3',5'-trideoxy-beta-D-allofuranosyl)thymine (2; homo-AZT), the 5'-C-(hydroxymethyl) derivatives of AZT 1-(3'-azido-2',3'- dideoxy-beta-D-allofuranosyl)thymine (3) and 1-(3'-azido-2',3'-dideoxy-alpha-L-talofuranosyl)thymine (4), and the 5'-C-methyl derivatives of AZT 1-(3'-azido-2',3',6'-trideoxy-beta-D-allofuranosyl)thymine (5) and 1-(3'-azido-2',3',6'-trideoxy-alpha-L-talofuranosyl)thymine (6). Compounds 2-6 were evaluated for their inhibitory effect on human immunodeficiency virus type 1 (HIV-1) and type 2 (HIV-2) replication in MT-4 cells and found inactive at subtoxic concentrations. Compounds 2-4 and 6 are not effective against herpes simplex virus type 1 (HSV-1) and type 2 (HIV-2), vaccinia virus (VV), and vesicular stomatitis virus (VSV) at 400 micrograms/mL. 5 is slightly active against HSV-1, HSV-2 and VV at 150, 300, and 300 micrograms/mL, respectively.
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PMID:Side-chain derivatives of biologically active nucleosides. 1. Side-chain analogs of 3'-azido-3'-deoxythymidine (AZT). 132 81

A series of four mannose(Man)-, three N-acetylglucosamine (GlcNAc)n-, ten N-acetylgalactosamine/galactose(GalNAc/Gal)-, one 5-acetylneuraminic acid (alpha-2,3-Gal/GalNAc)- and one 5-acetylneuroaminic acid(alpha-2,6-Gal/Gal-NAc)-specific plant agglutinins were evaluated for their antiviral activity in vitro. the mannose-specific lectins from the orchid species Cymbidium hybrid (CA), Epipactis helleborine (EHA) and Listera ovata (LOA) were highly inhibitory to human immunodeficiency virus type 1 (HIV-1) and type 2 (HIV-2) in MT-4, and showed a marked anti-human cytomegalovirus (CMV), respiratory syncytial virus (RSV) and influenza A virus activity in HEL, HeLa and MDCK cells, respectively. The 50% effective concentration (EC50) of CA and EHA for HIV ranged from 0.04 to 0.08 micrograms/ml, that is about 3 orders of magnitude below their toxicity threshold (50% inhibitory concentration for MT-4 cell growth: 54 to 60 micrograms/ml). Also, the (GlcNAc)n-specific lectin from Urtica dioica (UDA) was inhibitory to HIV-1-, HIV-2-, CMV-, RSV- and influenza A virus-induced cytopathicity at an EC50 ranging from 0.3 to 9 micrograms/ml. The GalNAc/Gal-, alpha-2,3-Gal/GalNAc- or alpha-2,6-Gal/GalNAc-specific lectins were not inhibitory to HIV or CMV at non-toxic concentrations. CA, EHA and UDA proved to be potent inhibitors of syncytium formation between persistently HIV-1- and HIV-2-infected HUT-78 cells and CD4+ Molt/4 (clone 8) cells (EC50: 0.2-2 micrograms/ml). Unlike dextran sulfate, the plant lectins CA, EHA and UDA did not interfere with HIV-1 adsorption to MT-4 cells and RSV- and influenza A virus adsorption to HeLa and MDCK cells, respectively. They presumably interact at the level of virion fusion with the target cell.
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PMID:The mannose-specific plant lectins from Cymbidium hybrid and Epipactis helleborine and the (N-acetylglucosamine)n-specific plant lectin from Urtica dioica are potent and selective inhibitors of human immunodeficiency virus and cytomegalovirus replication in vitro. 132 50

We have previously reported the potent stimulation effect of lignin on the iodination of myeloperoxidase (MPO)-positive cells. We investigated here the anti-HIV (human immunodeficiency virus) activity of lignins in the MPO-positive (HL-60) and -negative (U-937) human myelogenous leukemic cell lines. Natural lignified material and dehydrogenation polymers, but not their precursors, effectively inhibited the cytopathic effect of HIV infection in both these cells as well as in MT-4 and MOLT-4 cells. HIV infection caused significant reduction of MPO activity in HL-60 cells, regardless of the presence or absence of lignins. These data suggest that MPO might not be involved in the anti-HIV activity induction by lignins.
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PMID:Effect of lignins on HIV-induced cytopathogenicity and myeloperoxidase activity in human myelogenous leukemic cell lines. 133 79

Compounds with medium relative molecular masses active against human immunodeficiency virus (HIV) were synthesized. Sulfated alkyl oligosaccharides such as sulfated octadecyl maltohexaoside, sulfated dodecyl laminaripentaoside and sulfated dodecyl laminari-oligomer caused 50% inhibition of virus infection in the EC50 range of 0.4-0.7 microgram/mL in vitro using the MT-4 cell line and HIV-1HTLV-IIIB virus isolate, though sulfated oligosaccharides without alkyl groups showed low anti-HIV activities. This anti-HIV activity was close to the EC50 of 0.43 microgram/mL for a highly active sulfated polysaccharide curdlan sulfate which was reported to inhibit completely the HIV infection at a concentration as low as 3.3 micrograms/mL. These compounds were also active against HIV-2 and a clinically isolated HIV-1 with reduced AZT sensitivity. For such sulfated alkyl oligosaccharides, the mechanism of inhibition of HIV infection was assumed to be the inhibition of HIV binding to the cell and to some extent the interaction of the alkyl portion with the lipid bilayer of the virus.
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PMID:Sulfated alkyl oligosaccharides with potent inhibitory effects on human immunodeficiency virus infection. 135 27


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