scholarly journals Influence of Prior Exposure to Zidovudine on Stavudine Phosphorylation In Vivo and Ex Vivo

2001 ◽  
Vol 45 (2) ◽  
pp. 577-582 ◽  
Author(s):  
P. G. Hoggard ◽  
S. D. Sales ◽  
D. Phiboonbanakit ◽  
J. Lloyd ◽  
B. A. Maher ◽  
...  
Keyword(s):  
High Performance ◽  
Mononuclear Cells ◽  
Ex Vivo ◽  
Hiv Positive ◽  
Peripheral Blood Mononuclear ◽  
Significant Difference ◽  
Immunodeficiency Virus ◽  
Ex Vivo Study ◽  
Level 2

ABSTRACT Intracellular phosphorylation of stavudine (d4T) and zidovudine (ZDV) was investigated in peripheral blood mononuclear cells (PBMCs) isolated from ZDV-naive and ZDV-experienced human immunodeficiency virus (HIV)-positive patients. An in vivo study measured the amount of d4T triphosphate (d4TTP), while an ex vivo study assessed the capacity of cells to phosphorylate added d4T. Endogenous dTTP was also measured. d4TTP and dTTP were determined in vivo using a reverse transcriptase chain termination assay. In ex vivo studies, d4T (1 μM) was incubated in resting and phytohemagglutinin-stimulated (10 μg ml−1; 72 h) PBMCs for 24 h. After washing and methanol extraction, radiolabeled anabolites were detected by high-performance liquid chromatography. d4TTP reached its highest level 2 to 4 h after dosing (0.21 ± 0.14 pmol/106cells; n = 27 [mean ± standard deviation]). Comparison of ZDV-naive and ZDV-experienced individuals showed no significant difference in levels of d4TTP (ZDV naive, 0.23 ± 0.17 pmol/106 cells [n = 7] versus ZDV experienced, 0.20 ± 0.14 pmol/106 cells [n = 20]; P = 0.473) or the d4TTP/dTTP ratio (0.14 ± 0.12 [n = 7] and 0.10 ± 0.08 [n = 20], respectively;p = 0.391). Ex vivo data demonstrated no significant difference in the formation of d4TTP or total d4T phosphates in naive and experienced patients (0.086 ± 0.055 pmol/106cells in ZDV-naive patients [n = 17] versus 0.081 ± 0.038 pmol/106 cells in ZDV-experienced patients [n = 22]; P = 0.767). The ability of HIV-infected patients to phosphorylate d4T in vivo and ex vivo was unchanged with increasing exposure to ZDV.

scholarly journals Interleukin-7-Dependent Production of RANTES That Correlates with Human Immunodeficiency Virus Disease Progression

2003 ◽  
Vol 77 (7) ◽  
pp. 4389-4395 ◽  
Author(s):  
Anuska Llano ◽  
Jordi Barretina ◽  
Arantxa Gutiérrez ◽  
Bonaventura Clotet ◽  
José A. Esté
Keyword(s):  
Human Immunodeficiency Virus ◽  
Disease Progression ◽  
Mononuclear Cells ◽  
Ex Vivo ◽  
Virus Disease ◽  
Chemokine Production ◽  
Interleukin 7 ◽  
Cell Counts ◽  
Immunodeficiency Virus

ABSTRACT There is a relationship between CD4-T-cell number and circulating interleukin 7 (IL-7) levels in human immunodeficiency virus (HIV)-positive individuals. Here, we show that IL-7 induced a dose-dependent production of CCL3 (MIP-1α), CCL4 (MIP-1β), and CCL5 (RANTES) in peripheral blood mononuclear cells (PBMC), ex vivo tonsil lymphoid tissue of HIV− individuals, and PBMC from HIV+ individuals, suggesting that IL-7 may regulate β-chemokine production in vivo. In a cross-sectional study of HIV+ individuals (n = 130), a weak but significant correlation between IL-7 and RANTES was noted (r = 0.379; P < 0.001). Remarkably, the correlation between IL-7 and RANTES increased to an r value of 0.798 (P < 0.001) if individuals with low CD4 cell counts (<200 cells/μl) were excluded from the analysis. Our results suggest that there is a relationship between IL-7 and the production of RANTES both in vitro and in vivo that is lost in immune-compromised patients (CD4 count of <200 cells/μl) but that could be restored by antiretroviral therapy. Unlike the case for IL-7, high levels of RANTES suggest an intermediate stage of HIV disease progression.

scholarly journals In Vivo Antiretroviral Activity of Stampidine in Chronically Feline Immunodeficiency Virus-Infected Cats

2003 ◽  
Vol 47 (4) ◽  
pp. 1233-1240 ◽  
Author(s):  
Fatih M. Uckun ◽  
Chun-Lin Chen ◽  
Peter Samuel ◽  
Sharon Pendergrass ◽  
T. K. Venkatachalam ◽  
...  
Keyword(s):  
Dose Level ◽  
Peripheral Blood Mononuclear Cells ◽  
Feline Immunodeficiency Virus ◽  
Peripheral Blood ◽  
Mononuclear Cells ◽  
Peripheral Blood Mononuclear ◽  
Immunodeficiency Virus ◽  
Blood Mononuclear Cells ◽  
Antiretroviral Activity

ABSTRACT Here we report the antiretroviral activity of the experimental nucleoside reverse transcriptase inhibitor (NRTI) compound stampidine in cats chronically infected with feline immunodeficiency virus (FIV). Notably, a single oral bolus dose of 50 or 100 mg of stampidine per kg resulted in a transient ≥1-log decrease in the FIV load of circulating peripheral blood mononuclear cells in five of six FIV-infected cats and no side effects. A 4-week stampidine treatment course with twice-daily administration of hard gelatin capsules containing 25 to 100 mg of stampidine per kg was also very well tolerated by cats at cumulative dose levels as high as 8.4 g/kg and exhibited a dose-dependent antiretroviral effect. One of three cats treated at the 25-mg/kg dose level, three of three cats treated at the 50-mg/kg dose level, and three of three cats treated at the 100-mg/kg dose level (but none of three control cats treated with placebo pills) showed a therapeutic response, as evidenced by a ≥1-log reduction in the FIV load in peripheral blood mononuclear cells within 2 weeks. The previously documented in vitro and in vivo antiretroviral activity of stampidine against primary clinical human immunodeficiency virus type 1 isolates with genotypic and/or phenotypic NRTI resistance, together with its favorable animal toxicity profile, pharmacokinetics, and in vivo antiretroviral activity in FIV-infected cats, warrants further development of this promising new NRTI compound.

scholarly journals Characteristics of a Pathogenic Molecular Clone of an End-Stage Serum-Derived Variant of Simian Immunodeficiency Virus (SIVF359)

2001 ◽  
Vol 75 (19) ◽  
pp. 9328-9338 ◽  
Author(s):  
Lennart Holterman ◽  
Rob Dubbes ◽  
James Mullins ◽  
Gerald Learn ◽  
Henk Niphuis ◽  
...  
Keyword(s):  
Simian Immunodeficiency Virus ◽  
Peripheral Blood ◽  
Mononuclear Cells ◽  
Human Peripheral Blood ◽  
Peripheral Blood Lymphocytes ◽  
Peripheral Blood Mononuclear ◽  
Molecular Clone ◽  
Immunodeficiency Virus ◽  
End Stage

ABSTRACT End-stage simian immunodeficiency virus (SIV) isolates are suggested to be the most fit of the evolved virulent variants that precipitate the progression to AIDS. To determine if there were common characteristics of end-stage variants which emerge from accelerated cases of AIDS, a molecular clone was derived directly from serum following in vivo selection of a highly virulent SIV isolate obtained by serial end-stage passage in rhesus monkeys (Macaca mulatta). This dominant variant caused a marked cytopathic effect and replicated to very high levels in activated but not resting peripheral blood lymphocytes. Furthermore, although this clone infected but did not replicate to detectable levels in rhesus monocyte-derived macrophages, these cells were able to transmit infection to autologous T cells upon contact. Interestingly, although at low doses this end-stage variant did not use any of the known coreceptors except CCR5, it was able to infect and replicate in human peripheral blood mononuclear cells homozygous for the Δ32 deletion of CCR5, suggesting the use of a novel coreceptor. It represents the first pathogenic molecular clone of SIV derived from viral RNA in serum and provides evidence that not only the genetic but also the biological characteristics acquired by highly fit late-stage disease variants may be distinct in different hosts.

scholarly journals CD4-Negative Cells Bind Human Immunodeficiency Virus Type 1 and Efficiently Transfer Virus to T Cells

2000 ◽  
Vol 74 (18) ◽  
pp. 8550-8557 ◽  
Author(s):  
Gene G. Olinger ◽  
Mohammed Saifuddin ◽  
Gregory T. Spear
Keyword(s):  
Human Immunodeficiency Virus ◽  
T Cells ◽  
Mononuclear Cells ◽  
Cell Types ◽  
Virus Binding ◽  
Peripheral Blood Mononuclear ◽  
Human Immunodeficiency Virus Strain ◽  
Immunodeficiency Virus

ABSTRACT The ability of human immunodeficiency virus strain MN (HIVMN), a T-cell line-adapted strain of HIV, and X4 and R5 primary isolates to bind to various cell types was investigated. In general, HIVMN bound to cells at higher levels than did the primary isolates. Virus bound to both CD4-positive (CD4+) and CD4-negative (CD4−) cells, including neutrophils, Raji cells, tonsil mononuclear cells, erythrocytes, platelets, and peripheral blood mononuclear cells (PBMC), although virus bound at significantly higher levels to PBMC. However, there was no difference in the amount of HIV that bound to CD4-enriched or CD4-depleted PBMC. Virus bound to CD4− cells was up to 17 times more infectious for T cells in cocultures than was the same amount of cell-free virus. Virus bound to nucleated cells was significantly more infectious than virus bound to erythrocytes or platelets. The enhanced infection of T cells by virus bound to CD4− cells was not due to stimulatory signals provided by CD4− cells or infection of CD4− cells. However, anti-CD18 antibody substantially reduced the enhanced virus replication in T cells, suggesting that virus that bound to the surface of CD4−cells is efficiently passed to CD4+ T cells during cell-cell adhesion. These studies show that HIV binds at relatively high levels to CD4− cells and, once bound, is highly infectious for T cells. This suggests that virus binding to the surface of CD4− cells is an important route for infection of T cells in vivo.

scholarly journals Antiviral Activity and Pharmacokinetics of 1-(2,3-Dideoxy-2-Fluoro-β-l-Glyceropent-2-Enofuranosyl)Cytosine

2003 ◽  
Vol 47 (6) ◽  
pp. 1922-1928 ◽  
Author(s):  
Huachun Chen ◽  
S. Balakrishna Pai ◽  
Selwyn J. Hurwitz ◽  
Chung K. Chu ◽  
Yuliya Glazkova ◽  
...  
Keyword(s):  
Mononuclear Cells ◽  
Terminal Phase ◽  
Peripheral Blood Mononuclear ◽  
B Virus ◽  
Immunodeficiency Virus ◽  
The Central Nervous System ◽  
Collection Period ◽  
Intravenous And Oral Administration ◽  
Hepg2 2.2.15

ABSTRACT 1-(2,3-Dideoxy-2-fluoro-β-l-glyceropent-2-enofuranosyl)cytosine (l-2′-Fd4C) is an l-nucleoside analogue with both anti-human immunodeficiency virus (HIV) and anti-hepatitis B virus (HBV) activity with median effective concentrations of 0.12 μM in peripheral blood mononuclear cells and 0.002 μM in HepG2-2.2.15 cells, respectively. The purpose of this study was to examine the antihepadnavirus potency and pharmacokinetics of l-2′-Fd4C in vivo. HBV-transgenic mice treated intraperitoneally with l-2′-Fd4C showed a reduction of HBV levels in their blood comparable to that produced by lamivudine. The pharmacokinetics of l-2′-Fd4C in rhesus monkeys was evaluated after intravenous and oral administration. The concentrations in plasma declined in a biexponential manner after intravenous administration, with a long terminal-phase half-life of 5.02 h. The steady-state volumes of distribution and systemic clearance were 1.09 liter · kg−1 and 0.25 liter · h−1 · kg−1, respectively, with a renal clearance of 0.16 liter · h−1 · kg−1. The oral bioavailability was approximately 44%. About 53% of the compound administered intravenously and 19% of that administered orally were recovered unchanged in the urine within the 24-h urine collection period, and no other metabolite was detected. The compound penetrated the central nervous system at concentrations that exceeded the median effective antiviral concentration against HIV in cell cultures. Based upon these observations, further testing to develop this agent for treatment of HIV and HBV infections is warranted.

scholarly journals Simian Immunodeficiency Virus SIVagm Efficiently Utilizes Non-CCR5 Entry Pathways in African Green Monkey Lymphocytes: Potential Role for GPR15 and CXCR6 as Viral Coreceptors

2015 ◽  
Vol 90 (5) ◽  
pp. 2316-2331 ◽  
Author(s):  
Nadeene E. Riddick ◽  
Fan Wu ◽  
Kenta Matsuda ◽  
Sonya Whitted ◽  
Ilnour Ourmanov ◽  
...  
Keyword(s):  
T Cells ◽  
Mononuclear Cells ◽  
Rhesus Macaques ◽  
Target Cells ◽  
Peripheral Blood Mononuclear ◽  
Immunodeficiency Virus ◽  
Sooty Mangabeys ◽  
Natural Hosts

ABSTRACTAfrican green monkeys (AGM) are natural hosts of simian immunodeficiency virus (SIV), and infection in these animals is generally nonpathogenic, whereas infection of nonnatural hosts, such as rhesus macaques (RM), is commonly pathogenic. CCR5 has been described as the primary entry coreceptor for SIVin vivo, while human-derived CXCR6 and GPR15 also appear to be usedin vitro. However, sooty mangabeys that are genetically deficient in CCR5 due to an out-of-frame deletion are infectible with SIVsmm, indicating that SIVsmm can use alternative coreceptorsin vivo. In this study, we examined the CCR5 dependence of SIV strains derived from vervet AGM (SIVagmVer) and the ability of AGM-derived GPR15 and CXCR6 to serve as potential entry coreceptors. We found that SIVagmVer replicated efficiently in AGM and RM peripheral blood mononuclear cells (PBMC) in the presence of the CCR5 antagonist maraviroc, despite the fact that maraviroc was capable of blocking the CCR5-tropic strains SIVmac239, SIVsmE543-3, and simian-human immunodeficiency virus SHIV-AD8 in RM PBMC. We also found that AGM CXCR6 and AGM GPR15, to a lesser extent, supported entry of pseudotype viruses bearing SIVagm envelopes, including SIVagm transmitted/founder envelopes. Lastly, we found that CCR5, GPR15, and CXCR6 mRNAs were detected in AGM and RM memory CD4+T cells. These results suggest that GPR15 and CXCR6 are expressed on AGM CD4+T cells and are potential alternative coreceptors for SIVagm usein vivo. These data suggest that the use of non-CCR5 entry pathways may be a common feature of SIV replication in natural host species, with the potential to contribute to nonpathogenicity in these animals.IMPORTANCEAfrican green monkeys (AGM) are natural hosts of SIV, and infection in these animals generally does not cause AIDS, whereas SIV-infected rhesus macaques (RM) typically develop AIDS. Although it has been reported that SIV generally uses CD4 and CCR5 to enter target cellsin vivo, other molecules, such as GPR15 and CXCR6, also function as SIV coreceptorsin vitro. In this study, we investigated whether SIV from vervet AGM can use non-CCR5 entry pathways, as has been observed in sooty mangabeys. We found that SIVagmVer efficiently replicated in AGM and RM peripheral blood mononuclear cells in the presence of the CCR5 antagonist maraviroc, suggesting that non-CCR5 entry pathways can support SIVagm entry. We found that AGM-derived GPR15 and CXCR6 support SIVagmVer entryin vitroand may serve as entry coreceptors for SIVagmin vivo, since their mRNAs were detected in AGM memory CD4+T cells, the preferred target cells of SIV.

scholarly journals Novel, Live Attenuated Simian Immunodeficiency Virus Constructs Containing Major Deletions in Leader RNA Sequences

2001 ◽  
Vol 75 (6) ◽  
pp. 2776-2785 ◽  
Author(s):  
Yongjun Guan ◽  
James B. Whitney ◽  
Chen Liang ◽  
Mark A. Wainberg
Keyword(s):  
Tissue Culture ◽  
Simian Immunodeficiency Virus ◽  
Mononuclear Cells ◽  
Polyacrylamide Gel Electrophoresis ◽  
Wild Type Virus ◽  
Replication Capacity ◽  
Peripheral Blood Mononuclear ◽  
Immunodeficiency Virus

ABSTRACT We have constructed a series of simian immunodeficiency virus (SIV) mutants containing deletions within a 97-nucleotide (nt) region of the leader sequence. Deletions in this region markedly decreased the replication capacity in tissue culture, i.e., in both the C8166 and CEMx174 cell lines, as well as in rhesus macaque peripheral blood mononuclear cells. In addition, these deletions adversely affected the packaging of viral genomic RNA into virions, the processing of Gag precursor proteins, and patterns of viral proteins in virions, as assessed by biochemical labeling and polyacrylamide gel electrophoresis. Different levels of attenuation were achieved by varying the size and position of deletions within this 97-nt region, and among a series of constructs that were generated, it was possible to rank in vitro virulence relative to that of wild-type virus. In all of these cases, the most severe impact on viral replication was observed when the deletions that were made were located at the 3′ rather than 5′ end of the leader region. The potential of viral reversion over protracted periods was investigated by repeated viral passage in CEMx174 cells. The results showed that several of these constructs showed no signs of reversion after more than 6 months in tissue culture. Thus, a series of novel, attenuated SIV constructs have been developed that are significantly impaired in replication capacity yet retain all viral genes. One of these viruses, termed SD4, may be appropriate for study with rhesus macaques, in order to determine whether reversions will occur in vivo and to further study this virus as a candidate for attenuated vaccination.

scholarly journals Simultaneous Quantitation of Intracellular Zidovudine and Lamivudine Triphosphates in Human Immunodeficiency Virus-Infected Individuals

2000 ◽  
Vol 44 (11) ◽  
pp. 3097-3100 ◽  
Author(s):  
Jose F. Rodriguez ◽  
Jorge L. Rodriguez ◽  
Jorge Santana ◽  
Hermes García ◽  
Osvaldo Rosario
Keyword(s):  
Human Immunodeficiency Virus ◽  
Highly Active Antiretroviral Therapy ◽  
Mononuclear Cells ◽  
Solid Phase ◽  
Parent Compound ◽  
Hiv Positive ◽  
Peripheral Blood Mononuclear ◽  
Limit Of Quantitation ◽  
Immunodeficiency Virus

ABSTRACT Highly active antiretroviral therapy (HAART) is the standard treatment for infection with human immunodeficiency virus (HIV). The most common HAART regimen consists of the combination of at least one protease inhibitor (PI) with two nucleoside reverse transcriptase inhibitors (NRTIs). Contrary to PIs, NRTIs require intracellular activation from the parent compound of their triphosphate moiety to suppress HIV replication. Simultaneous intracellular determination of two NRTI triphosphates is difficult to accomplish due to their relatively small concentrations in peripheral blood mononuclear cells (PBMCs), requiring large amounts of blood from HIV-positive patients. Recently, we described a method to determine intracellular zidovudine triphosphate (ZDV-TP) concentrations in HIV-infected patients by using solid-phase extraction and tandem mass spectrometry. The limit of quantitation (LOQ) for ZDV-TP was 0.10 pmol, and the method was successfully used for the determination of ZDV-TP in HIV-positive patients. In this study, we enhanced the aforementioned method by the simultaneous quantitation of ZDV-TP and lamivudine triphosphate (3TC-TP) in PBMCs from HIV-infected patients. The LOQ for 3TC-TP was 4.0 pmol, with an interassay coefficient of variation and an accuracy of 7 and 12%, respectively. This method was successfully applied to the simultaneous in vivo determination of the ZDV-TP and 3TC-TP pharmacokinetic profiles from HIV-infected patients receiving HAART.

scholarly journals Characterization of the Follicular Dendritic Cell Reservoir of Human Immunodeficiency Virus Type 1

2008 ◽  
Vol 82 (11) ◽  
pp. 5548-5561 ◽  
Author(s):  
Brandon F. Keele ◽  
Loubna Tazi ◽  
Suzanne Gartner ◽  
Yiling Liu ◽  
Trever B. Burgon ◽  
...  
Keyword(s):  
Genetic Diversity ◽  
Human Immunodeficiency Virus ◽  
Mononuclear Cells ◽  
Follicular Dendritic Cell ◽  
Peripheral Blood Mononuclear ◽  
Virus Particles ◽  
Hiv Rna ◽  
Immunodeficiency Virus ◽  
Follicular Dendritic

ABSTRACT Throughout the natural course of human immunodeficiency virus (HIV) infection, follicular dendritic cells (FDCs) trap and retain large quantities of particle-associated HIV RNA in the follicles of secondary lymphoid tissue. We have previously found that murine FDCs in vivo could maintain trapped virus particles in an infectious state for at least 9 months. Here we sought to determine whether human FDCs serve as an HIV reservoir, based on the criteria that virus therein must be replication competent, genetically diverse, and archival in nature. We tested our hypothesis using postmortem cells and tissues obtained from three HIV-infected subjects and antemortem blood samples obtained from one of these subjects. Replication competence was determined using coculture, while genetic diversity and the archival nature of virus were established using phylogenetic and population genetics methods. We found that FDC-trapped virus was replication competent and demonstrated greater genetic diversity than that of virus found in most other tissues and cells. Antiretrovirus-resistant variants that were not present elsewhere were also detected on FDCs. Furthermore, genetic similarity was observed between FDC-trapped HIV and viral species recovered from peripheral blood mononuclear cells obtained 21 and 22 months antemortem, but was not present in samples obtained 4 and 18 months prior to the patient's death, indicating that FDCs can archive HIV. These data indicate that FDCs represent a significant reservoir of infectious and diverse HIV, thereby providing a mechanism for viral persistence for months to years.

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