scholarly journals Targeting RNase L to Human Immunodeficiency Virus RNA with 2-5A-Antisense

1998 ◽  
Vol 9 (3) ◽  
pp. 225-231 ◽  
Author(s):  
Player ◽  
RK Maitra ◽  
RH Silverman ◽  
PF Torrence
Keyword(s):  
Human Immunodeficiency Virus ◽  
Solid Phase ◽  
Rnase L ◽  
Hiv Rna ◽  
Cleavage Activity ◽  
Virus Rna ◽  
Phosphoramidite Chemistry ◽  
Immunodeficiency Virus ◽  
Antisense Approach ◽  
A Cell

In an attempt to develop a lead for the application of 2–5A-antisense to the targeted destruction of human immunodeficiency virus (HIV) RNA, specific target sequences within the HIV mRNAs were identified by analysis of the theoretical secondary structure. 2-5A-antisense chimeras were chosen against a total of 11 different sequences: three in the gag mRNA, three in the rev mRNA and five in the tat mRNA. 2-5A-antisense chimera synthesis was accomplished using solid-phase phosphoramidite chemistry. These chimeras were evaluated for their activity in a cell-free assay system using purified recombinant human RNase L to effect cleavage of 32P-labelled RNA transcripts of plasmids derived from HIV NL4-3. This screening revealed that of the three 2-5A-antisense chimeras targeted against gag mRNA, only one had significant HIV RNA cleavage activity, approximately10-fold-reduced compared to the parent 2-5A tetramer and comparable to that reported for the prototypical 2-5A-anti-PKR chimera, targeted against PKR mRNA. The cleavage activity of this chimera was specific, since a scrambled antisense domain chimera and a chimera without the key 5′-monophosphate moiety were both inactive. The 10 other 2-5A-antisense chimeras against tat and rev had significantly less activity. These results imply that HIV gag RNA, like PKR RNA and a model HIV tat-oligoA- vif RNA, can be cleaved using the 2-5A-antisense approach. The results further imply that not all regions of a potential RNA target are accessible to the 2-5A-antisense approach.

scholarly journals Anti-Human Immunodeficiency Virus Activity of Tau Interferon in Human Macrophages: Involvement of Cellular Factors and β-Chemokines

2003 ◽  
Vol 77 (23) ◽  
pp. 12914-12920 ◽  
Author(s):  
Christine Rogez ◽  
Marc Martin ◽  
Nathalie Dereuddre-Bosquet ◽  
Jacques Martal ◽  
Dominique Dormont ◽  
...  
Keyword(s):  
Human Immunodeficiency Virus ◽  
Human Monocyte ◽  
Type I ◽  
Rnase L ◽  
Oligoadenylate Synthetase ◽  
Hiv Replication ◽  
Human Macrophages ◽  
Hiv Rna ◽  
Type I Ifns ◽  
Immunodeficiency Virus

ABSTRACT Tau interferon (IFN-τ) is a noncytotoxic type I IFN responsible for maternal recognition of the fetus in ruminants. IFN-τ inhibits human immunodeficiency virus (HIV) replication more strongly than human IFN-α, particularly in human monocyte-derived macrophages. In this study performed in human macrophages, IFN-τ efficiently inhibited the early steps of the biological cycle of HIV, decreasing intracellular HIV RNA and inhibiting the initiation of the reverse transcription of viral RNA into proviral DNA. Two mechanisms induced by IFN-τ treatment in macrophages may account for this inhibition: (i) the synthesis of the cellular antiviral factors such as 2′,5′-oligoadenylate synthetase/RNase L and MxA protein and (ii) an increased production of MIP-1α, MIP-1β, and RANTES, which are natural ligands of CCR5, the principal coreceptor of HIV on macrophages. Our results suggest that IFN-τ induces the same antiviral pathways in macrophages as other type I IFNs but without associated toxicity.

scholarly journals RNase L Inhibitor Is Induced during Human Immunodeficiency Virus Type 1 Infection and Down Regulates the 2-5A/RNase L Pathway in Human T Cells

1999 ◽  
Vol 73 (1) ◽  
pp. 290-296 ◽  
Author(s):  
Camille Martinand ◽  
Céline Montavon ◽  
Tamim Salehzada ◽  
Michelle Silhol ◽  
Bernard Lebleu ◽  
...  
Keyword(s):  
Human Immunodeficiency Virus ◽  
Human Immunodeficiency Virus Type ◽  
Virus Type ◽  
Rnase L ◽  
Hiv Replication ◽  
Hiv Rna ◽  
Rnase L Inhibitor ◽  
Immunodeficiency Virus ◽  
Infected Cells

ABSTRACT The interferon-regulated 2-5A/RNase L pathway plays a major role in the antiviral and antiproliferative activities of these cytokines. Several viruses, however, have evolved strategies to escape the antiviral activity of the 2-5A/RNase L pathway. In this context, we have cloned a cDNA coding for the RNase L inhibitor (RLI), a protein that specifically inhibits RNase L and whose regulated expression in picornavirus-infected cells down regulates the activity of the 2-5A/RNase L pathway. We show here that RLI increases during the course of human immunodeficiency virus type 1 (HIV-1) infection, which may be related to the downregulation of RNase L activity that has been described to occur in HIV-infected cells. In order to establish a possible causal relationship between these observations, we have stably transfected H9 cells with RLI sense or antisense cDNA-expressing vectors. The overexpression of RLI causes a decrease in RNase L activity and a twofold enhancement of HIV production. This increase in HIV replication correlates with an increase in HIV RNA and proteins. In contrast, reduction of RLI levels in RLI antisense cDNA-expressing clones reverses the inhibition of RNase L activity associated with HIV multiplication and leads to a threefold decrease in the viral load. This anti-HIV activity correlated with a decrease in HIV RNA and proteins. These findings demonstrate that the level of RLI, via its modulation of RNase L activity, can severely impair HIV replication and suggest the involvement of RLI in the inhibition of the 2-5A/RNase L system observed during HIV infection.

Combination Therapy With Stavudine and Didanosine in Children With Advanced Human Immunodeficiency Virus Infection: Pharmacokinetic Properties, Safety, and Immunologic and Virologic Effects

PEDIATRICS ◽  
1996 ◽  
Vol 97 (6) ◽  
pp. 886-890
Author(s):  
Mark W. Kline ◽  
Courtney V. Fletcher ◽  
Marianne E. Federici ◽  
Alice T. Harris ◽  
Kim D. Evans ◽  
...  
Keyword(s):  
Human Immunodeficiency Virus ◽  
Combination Therapy ◽  
Lymphocyte Count ◽  
Hiv Disease ◽  
Hiv Rna ◽  
Immunodeficiency Virus ◽  
Pharmacokinetic Properties ◽  
Cd4 Lymphocyte Count ◽  
Cd4 Lymphocyte ◽  
Advanced Hiv Disease

Objectives. To obtain preliminary information on the pharmacokinetic properties, tolerance, safety, and antiviral activity of combination therapy with stavudine and didanosine in children with advanced human immunodeficiency virus (HIV) infection. Methods. Eight children (median age, 6.6 years; range, 2.8 to 12 years) with advanced HIV disease (median CD4+ lymphocyte count at baseline, 42 cells/µL; range, 8 to 553 cells/µL) were treated with stavudine (2 mg/kg per day in two divided doses) and didanosine (180 mg/m2 per day in two divided doses) for 24 weeks. Seven children had histories of prior zidovudine therapy. All children had received stavudine alone for 19 to 33 months before the addition of didanosine to the treatment regimen. Children were assessed clinically and with laboratory studies at baseline, weekly through week 4 of combination therapy, and every 4 weeks thereafter. Results. Analysis of stavudine and didanosine plasma half-life values, clearances, and area under the plasma concentration-versus-time curves revealed no obvious clinical pharmacokinetic interaction between the drugs through study week 12. Combination therapy was well tolerated, and there were no drug-associated clinical or laboratory adverse events. Signs and symptoms of peripheral neuropathy were not observed. All three children with baseline CD4+ lymphocyte counts greater than 50 cells/µL had greater than 20% increases in their counts within the first 12 weeks of therapy; CD4+ lymphocyte count increases were not observed in the other children. Plasma HIV RNA concentrations showed median declines of 0.88 log10 (range, -3.41 log10 to 0.31 log10) and 0.30 log10 (range, -0.63 log10 to 0.89 log10) at study weeks 12 and 24, respectively. Conclusions. Combination therapy with stavudine and didanosine was well tolerated and safe in this small group of children with advanced HIV disease. Plasma HIV RNA concentration declines suggest a favorable effect of therapy on virus load. These findings should be confirmed, and the regimen's clinical efficacy should be examined, in controlled studies of HIV-infected children with less-advanced disease.

scholarly journals Quantitation of Intracellular Triphosphate of Emtricitabine in Peripheral Blood Mononuclear Cells from Human Immunodeficiency Virus-Infected Patients

1999 ◽  
Vol 43 (9) ◽  
pp. 2245-2250 ◽  
Author(s):  
Albert Darque ◽  
Gilles Valette ◽  
Frank Rousseau ◽  
Laurene H. Wang ◽  
Jean-Pierre Sommadossi ◽  
...  
Keyword(s):  
Human Immunodeficiency Virus ◽  
Anion Exchange ◽  
Peripheral Blood Mononuclear Cells ◽  
Peripheral Blood ◽  
Mononuclear Cells ◽  
Solid Phase ◽  
Peripheral Blood Mononuclear ◽  
Limit Of Quantitation ◽  
Immunodeficiency Virus ◽  
Blood Mononuclear Cells

ABSTRACT An analytical methodology combining solid-phase extraction (SPE) and high-performance liquid chromatography (HPLC) was developed to quantitate the intracellular active 5′-triphosphate (TP) of β-l-2′,3′-dideoxy-5-fluoro-3′-thiacytidine (emtricitabine) (FTC) in human peripheral blood mononuclear cells (PBMCs). The FTC nucleotides, including 5′-mono-, di-, and triphosphates, were successively resolved on an anion-exchange SPE cartridge by applying a gradient of potassium chloride. The FTC-TP was subsequently digested to release the parent nucleoside that was finally analyzed by HPLC with UV detection (HPLC-UV). Validation of the methodology was performed by using PBMCs from healthy donors exposed to an isotopic solution of [3H]FTC with known specific activity, leading to the formation of intracellular FTC-TP that was quantitated by an anion-exchange HPLC method with radioactive detection. These levels of FTC-TP served as reference values and were used to validate the data obtained by HPLC-UV. The assay had a limit of quantitation of 4.0 pmol of FTC-TP (amount on column from approximately 107 cells). Intra-assay precision (coefficient of variation percentage of repeated measurement) and accuracy (percentage deviation of the nominal reference value), estimated by using quality control samples at 16.2, 60.7, and 121.5 pmol, ranged from 1.3 to 3.3% and −1.0 to 4.8%, respectively. Interassay precision and accuracy varied from 3.0 to 10.2% and from 2.5 to 6.7%, respectively. This methodology was successfully applied to the determination of FTC-TP in PBMCs of patients infected with human immunodeficiency virus after oral administration of various dosing regimens of FTC monotherapy.

scholarly journals Plasma Human Immunodeficiency Virus RNA Below 40 Copies/mL Is Rarein Untreated Persons Even in the First Years of Infection

1999 ◽  
Vol 180 (2) ◽  
pp. 526-529 ◽  
Author(s):  
Jean‐Jacques Lefrère ◽  
Martine Mariotti ◽  
Laurence Morand‐Joubert ◽  
Micheline Thauvin ◽  
Françoise Roudot‐Thoraval
Keyword(s):  
Human Immunodeficiency Virus ◽  
Virus Rna ◽  
Immunodeficiency Virus

scholarly journals Pharmacologic Characteristics of Indinavir, Didanosine, and Stavudine in Human Immunodeficiency Virus-Infected Children Receiving Combination Therapy

2000 ◽  
Vol 44 (4) ◽  
pp. 1029-1034 ◽  
Author(s):  
Courtney V. Fletcher ◽  
Richard C. Brundage ◽  
Rory P. Remmel ◽  
Linda M. Page ◽  
Dennis Weller ◽  
...  
Keyword(s):  
Human Immunodeficiency Virus ◽  
Trough Concentration ◽  
Area Under The Curve ◽  
Hiv Protease ◽  
Pharmacokinetic Parameters ◽  
Hiv Protease Inhibitors ◽  
Hiv Rna ◽  
Immunodeficiency Virus ◽  
Dosing Regimens ◽  
Outcomes For Children

ABSTRACT The use of human immunodeficiency virus (HIV) protease inhibitors in children has lagged behind that in adults because of the lack of suitable pediatric formulations and information on safe and effective dosing regimens. This study was designed to obtain pharmacokinetic information on indinavir, administered to HIV-infected children also receiving therapy with two nucleoside agents, and to explore relationships between pharmacokinetic parameters and anti-HIV effect. Indinavir was initiated at a dose of 500 mg/m2 every 8 h. Plasma indinavir concentrations were measured every 4 weeks; the dose or dosing interval was adjusted to maintain trough concentrations of ≥0.1 mg/liter. All children were evaluated clinically at baseline and every 4 weeks. Plasma HIV RNA was quantitated at baseline and at weeks 4, 12, and 24. Eighteen children participated in this study. The average daily dose of indinavir was 2,043 mg/m2; nine children received indinavir at 6-h intervals. Pharmacokinetic characteristics of indinavir (mean ± standard deviation) were the following: oral clearance, 1.4 ± 0.5 liters/h/kg; half-life, 1.1 ± 0.43 h; and trough concentration, 0.29 ± 0.32 mg/liter. In nine children that completed 24 weeks of therapy, the baseline-to-week-24 change in HIV RNA level was related to indinavir trough concentration and didanosine area under the curve. This study illustrates the ability to obtain pharmacokinetic information from children during routine clinic visits and to use this information to provide a safeguard against underdosing. The incorporation of pharmacologic knowledge with virologic, immunologic, and behavioral considerations should result in improved clinical outcomes for children infected with HIV.

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