scholarly journals Accelerated apoptosis in peripheral blood mononuclear cells (PBMCs) from human immunodeficiency virus type-1 infected patients and in CD4 cross-linked PBMCs from normal individuals

Blood ◽  
1993 ◽  
Vol 82 (11) ◽  
pp. 3392-3400 ◽  
Author(s):  
N Oyaizu ◽  
TW McCloskey ◽  
M Coronesi ◽  
N Chirmule ◽  
VS Kalyanaraman ◽  
...  
Keyword(s):  
T Cells ◽  
Cell Death ◽  
T Cell ◽  
Mononuclear Cells ◽  
Cross Linking ◽  
Peripheral Blood Mononuclear ◽  
Immunodeficiency Virus ◽  
Blood Mononuclear Cells ◽  
Hiv 1

This study investigates apoptosis as a mechanism for CD4+ T-cell depletion in human immunodeficiency virus type-1 (HIV-1) infection. Although several recent studies have shown that T cells of HIV-infected individuals show enhanced susceptibility to cell death by apoptosis, the mechanisms responsible for apoptosis are largely unknown. By using a flow cytometric technique and by morphology, we have quantitated the percentage of cells undergoing apoptosis in peripheral blood mononuclear cells (PBMCs) from HIV-seronegative donors and from HIV- infected asymptomatic patients. The PBMCs were cultured without any stimulus or with staphylococcus enterotoxin B, anti-T-cell receptor (TCR) alpha beta monoclonal antibody WT-31, or phytohemagglutinin for periods up to 6 days. In addition, we sought to determine whether cross- linking of CD4 followed by various modes of TCR stimulation in vitro could induce apoptosis in normal PBMCs. Here we show that (1) patient PMBCs undergo marked spontaneous apoptosis; (2) stimulation of T cells of patients as well as normal donors results in increased apoptosis; and (3) cross-linking of CD4 molecules is sufficient to induce apoptosis in CD4+ T cells if cross-linking is performed in unfractioned PBMCs, but not if CD4 molecules are cross-linked in purified T-cell preparations. These observations strongly suggest that accelerated cell death through apoptosis plays an important role in the pathogenesis of HIV-1 infection. At the same time, our observations implicate cross- linking of CD4 in vivo as a major contributor to this mechanism of accelerated cell death in HIV infection.

scholarly journals Accelerated apoptosis in peripheral blood mononuclear cells (PBMCs) from human immunodeficiency virus type-1 infected patients and in CD4 cross-linked PBMCs from normal individuals

Blood ◽  
1993 ◽  
Vol 82 (11) ◽  
pp. 3392-3400 ◽  
Author(s):  
N Oyaizu ◽  
TW McCloskey ◽  
M Coronesi ◽  
N Chirmule ◽  
VS Kalyanaraman ◽  
...  
Keyword(s):  
T Cells ◽  
Cell Death ◽  
T Cell ◽  
Mononuclear Cells ◽  
Cross Linking ◽  
Peripheral Blood Mononuclear ◽  
Immunodeficiency Virus ◽  
Blood Mononuclear Cells ◽  
Hiv 1

Abstract This study investigates apoptosis as a mechanism for CD4+ T-cell depletion in human immunodeficiency virus type-1 (HIV-1) infection. Although several recent studies have shown that T cells of HIV-infected individuals show enhanced susceptibility to cell death by apoptosis, the mechanisms responsible for apoptosis are largely unknown. By using a flow cytometric technique and by morphology, we have quantitated the percentage of cells undergoing apoptosis in peripheral blood mononuclear cells (PBMCs) from HIV-seronegative donors and from HIV- infected asymptomatic patients. The PBMCs were cultured without any stimulus or with staphylococcus enterotoxin B, anti-T-cell receptor (TCR) alpha beta monoclonal antibody WT-31, or phytohemagglutinin for periods up to 6 days. In addition, we sought to determine whether cross- linking of CD4 followed by various modes of TCR stimulation in vitro could induce apoptosis in normal PBMCs. Here we show that (1) patient PMBCs undergo marked spontaneous apoptosis; (2) stimulation of T cells of patients as well as normal donors results in increased apoptosis; and (3) cross-linking of CD4 molecules is sufficient to induce apoptosis in CD4+ T cells if cross-linking is performed in unfractioned PBMCs, but not if CD4 molecules are cross-linked in purified T-cell preparations. These observations strongly suggest that accelerated cell death through apoptosis plays an important role in the pathogenesis of HIV-1 infection. At the same time, our observations implicate cross- linking of CD4 in vivo as a major contributor to this mechanism of accelerated cell death in HIV infection.

scholarly journals Multifunctional Human Immunodeficiency Virus (HIV) Gag-Specific CD8+ T-Cell Responses in Rectal Mucosa and Peripheral Blood Mononuclear Cells during Chronic HIV Type 1 Infection

2007 ◽  
Vol 81 (11) ◽  
pp. 5460-5471 ◽  
Author(s):  
J. William Critchfield ◽  
Donna Lemongello ◽  
Digna H. Walker ◽  
Juan C. Garcia ◽  
David M. Asmuth ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
Mononuclear Cells ◽  
Rectal Mucosa ◽  
Peripheral Blood Mononuclear ◽  
Tnf Α ◽  
Immunodeficiency Virus ◽  
Ifn Γ ◽  
Hiv 1

ABSTRACT The intestinal tract is a lymphocyte-rich site that undergoes severe depletion of memory CD4+ T cells within days of simian immunodeficiency virus or human immunodeficiency virus type 1 (HIV-1) infection. An ensuing influx of virus-specific CD8+ T cells, which persist throughout the chronic phase of infection, has also been documented in the gastrointestinal tract. However, little is known of the functionality of these effector cells or their relationship to the disease course. In this study, we measured CD8+ T-cell responses to HIV-1 peptides in paired rectal and blood samples from chronically infected patients. In both blood and rectum, there was an immunodominant CD8+ T-cell response to HIV Gag compared to Pol and Env (P < 0.01). In contrast, cytomegalovirus pp65 peptides elicited gamma interferon (IFN-γ) secretion strongly in peripheral blood mononuclear cells (PBMC) but weakly in rectal CD8+ T cells (P = 0.015). Upon stimulation with HIV peptides, CD8+ T cells from both sites were capable of mounting complex responses including degranulation (CD107 expression) and IFN-γ and tumor necrosis factor alpha (TNF-α) production. In rectal tissue, CD107 release was frequently coupled with production of IFN-γ or TNF-α. In patients not on antiretroviral therapy, the magnitude of Gag-specific responses, as a percentage of CD8+ T cells, was greater in the rectal mucosa than in PBMC (P = 0.054); however, the breakdown of responding cells into specific functional categories was similar in both sites. These findings demonstrate that rectal CD8+ T cells are capable of robust and varied HIV-1-specific responses and therefore likely play an active role in eliminating infected cells during chronic infection.

scholarly journals Human Immunodeficiency Virus Type 1 DNA Sequences Genetically Damaged by Hypermutation Are Often Abundant in Patient Peripheral Blood Mononuclear Cells and May Be Generated during Near-Simultaneous Infection and Activation of CD4+ T Cells

2001 ◽  
Vol 75 (17) ◽  
pp. 7973-7986 ◽  
Author(s):  
Mario Janini ◽  
Melissa Rogers ◽  
Deborah R. Birx ◽  
Francine E. McCutchan
Keyword(s):  
Human Immunodeficiency Virus ◽  
T Cells ◽  
Peripheral Blood Mononuclear Cells ◽  
Peripheral Blood ◽  
Mononuclear Cells ◽  
Peripheral Blood Mononuclear ◽  
Immunodeficiency Virus ◽  
Blood Mononuclear Cells ◽  
Hiv 1

ABSTRACT G-to-A hypermutation has been sporadically observed in human immunodeficiency virus type 1 (HIV-1) proviral sequences from patient peripheral blood mononuclear cells (PBMC) and virus cultures but has not been systematically evaluated. PCR primers matched to normal and hypermutated sequences were used in conjunction with an agarose gel electrophoresis system incorporating an AT-binding dye to visualize, separate, clone, and sequence hypermutated and normal sequences in the 297-bp HIV-1 protease gene amplified from patient PBMC. Among 53 patients, including individuals infected with subtypes A through D and at different clinical stages, at least 43% of patients harbored abundant hypermutated, along with normal, protease genes. In 70 hypermutated sequences, saturation of G residues in the GA or GG dinucleotide context ranged from 20 to 94%. Levels of other mutants were not elevated, and G-to-A replacement was entirely restricted to GA or GG, and not GC or GT, dinucleotides. Sixty-nine of 70 hypermutated and 3 of 149 normal sequences had in-frame stop codons. To investigate the conditions under which hypermutation occurs in cell cultures, purified CD4+ T cells from normal donors were infected with cloned NL4-3 virus stocks at various times before and after phytohemagglutinin (PHA) activation. Hypermutation was pronounced when HIV-1 infection occurred simultaneously with, or a few hours after, PHA activation, but after 12 h or more after PHA activation, most HIV-1 sequences were normal. Hypermutated sequences generated in culture corresponded exactly in all parameters to those obtained from patient PBMC. Near-simultaneous activation and infection of CD4+ T cells may represent a window of susceptibility where the informational content of HIV-1 sequences is lost due to hypermutation.

scholarly journals T Cells Expressing Activated LFA-1 Are More Susceptible to Infection with Human Immunodeficiency Virus Type 1 Particles Bearing Host-Encoded ICAM-1

1998 ◽  
Vol 72 (3) ◽  
pp. 2105-2112 ◽  
Author(s):  
Jean-François Fortin ◽  
Réjean Cantin ◽  
Michel J. Tremblay
Keyword(s):  
Human Immunodeficiency Virus ◽  
T Cell ◽  
Peripheral Blood Mononuclear Cells ◽  
Peripheral Blood ◽  
Mononuclear Cells ◽  
Peripheral Blood Mononuclear ◽  
Immunodeficiency Virus ◽  
Blood Mononuclear Cells ◽  
Hiv 1

ABSTRACT The incorporation of host-derived proteins in nascent human immunodeficiency virus type 1 (HIV-1) particles is a well-established phenomenon. We recently demonstrated that the physical presence of host-encoded ICAM-1 glycoproteins on HIV-1 leads to a significant increase in virus infectivity in an ICAM-1/LFA-1-dependent fashion (J.-F. Fortin, R. Cantin, G. Lamontagne, and M. Tremblay, J. Virol. 71:3588–3596, 1997). We show here that conversion of LFA-1 to high affinity for ICAM-1 with the use of anti-LFA-1 antibodies (clones NKI-L16 and MEM83) markedly enhances the susceptibility of different target T-lymphoid cell lines, as well as of primary peripheral blood mononuclear cells, to infection by ICAM-1-bearing HIV-1 particles (6- to 95-fold). It is known that T-cell receptor (TCR) cross-linking induces a transient increase in LFA-1 affinity for ICAM-1. Treatment of peripheral blood mononuclear cells with anti-TCR antibodies (clone OKT3) resulted in a transient increase in susceptibility to infection by ICAM-1-positive virions that parallels the previously reported kinetics of the LFA-1/ICAM-1 adhesion mechanism. Our results led us to postulate that the strong interaction taking place between virally incorporated ICAM-1 and cell surface-activated LFA-1 markedly enhances the efficiency of virus binding and entry, thus favoring greater infection by ICAM-1-bearing HIV-1 particles. In view of the knowledge that primary HIV-1 isolates harbor host-derived ICAM-1 on their surfaces, these results provide new information about the role of host-derived ICAM-1 in the life cycle of HIV-1 and how it could positively modulate the dynamics of the viral infection, mainly in cellular compartments, such as the lymphoid tissues, where the level of cellular activation is high and where the probability of encountering a T cell expressing the activated LFA-1 form is also elevated.

scholarly journals Interleukin 7 Increases Human Immunodeficiency Virus Type 1 LAI-Mediated Fas-Induced T-Cell Death

2005 ◽  
Vol 79 (5) ◽  
pp. 3195-3199 ◽  
Author(s):  
Jean-Daniel Lelièvre ◽  
Frédéric Petit ◽  
Damien Arnoult ◽  
Jean-Claude Ameisen ◽  
Jérôme Estaquier
Keyword(s):  
Human Immunodeficiency Virus ◽  
T Cells ◽  
Cell Death ◽  
T Cell ◽  
Hiv Infection ◽  
Cell Infection ◽  
Interleukin 7 ◽  
Immunodeficiency Virus ◽  
Hiv 1

ABSTRACT Fas-mediated T-cell death is known to occur during human immunodeficiency virus (HIV) infection. In this study, we found that HIV type 1 LAI (HIV-1LAI) primes CD8+ T cells from healthy donors for apoptosis, which occurs after Fas ligation. This effect is counteracted by a broad caspase inhibitor (zVAD-fmk). Fas-mediated cell death does not depend on CD8+ T-cell infection, because it occurred in the presence of reverse transcriptase inhibitors. However, purified CD8+ T cells are sensitive to Fas only in the presence of soluble CD4. Finally, we found that interleukin 7 (IL-7) increases Fas-mediated CD4+ and CD8+ T-cell death induced by HIV-1LAI. Since high levels of IL-7 are a marker of poor prognosis during HIV infection, our data suggest that enhancement of Fas-mediated T-cell death by HIV-1LAI and IL-7 is one of the mechanisms involved in progression to AIDS.

scholarly journals Selection following isolation of human immunodeficiency virus type 1 in peripheral blood mononuclear cells and herpesvirus saimiri-transformed T cells is comparable

2002 ◽  
Vol 83 (6) ◽  
pp. 1343-1352 ◽  
Author(s):  
Natalie N. Zheng ◽  
Cherelyn Vella ◽  
Philippa J. Easterbrook ◽  
Rod S. Daniels
Keyword(s):  
Human Immunodeficiency Virus ◽  
T Cells ◽  
Peripheral Blood Mononuclear Cells ◽  
Mononuclear Cells ◽  
Cell Types ◽  
Herpesvirus Saimiri ◽  
Peripheral Blood Mononuclear ◽  
Immunodeficiency Virus ◽  
Blood Mononuclear Cells ◽  
Hiv 1

In attempts to improve isolation rates and virus yields for human immunodeficiency virus (HIV), the use of herpesvirus saimiri-immortalized T cells (HVS T cells) has been investigated as an alternative to/improvement over peripheral blood mononuclear cells (PBMCs). Here we characterize isolates rescued, in the two cell types, from two asymptomatic, long-term non-progressing HIV-1-infected individuals. All rescued viruses replicated in PBMCs and HVS T cells only, displaying a non-syncytium inducing (NSI) phenotype, and using CCR5 as co-receptor. Furthemore, PBMC/HVS T cell virus pairs displayed similar neutralization profiles. Full-length, expression-competent env genes were rescued from all virus isolates and directly from the patient samples using proviral DNA and viral RNA as templates. Compared with the sequences retrieved directly from the patient samples, both cell types showed similar selection characteristics. Whilst the selections were distinct for individual patient samples, they shared a common characteristic in selecting for viruses with increased negative charge across the V2 domain of the viral glycoproteins. The latter was observed at the env gene sequencing level for three other patients whose HIV strains were isolated in PBMCs only. This further supports a common selection for viral sequences that display a macrophage-tropic/NSI phenotype and shows that HVS T cells are a viable alternative to PBMCs for HIV-1 isolation.

Human serum alpha 1 acid glycoprotein reduces uptake, intracellular concentration, and antiviral activity of A-80987, an inhibitor of the human immunodeficiency virus type 1 protease.

1996 ◽  
Vol 40 (6) ◽  
pp. 1491-1497 ◽  
Author(s):  
J A Bilello ◽  
P A Bilello ◽  
K Stellrecht ◽  
J Leonard ◽  
D W Norbeck ◽  
...  
Keyword(s):  
Human Immunodeficiency Virus ◽  
Antiviral Activity ◽  
Peripheral Blood Mononuclear Cells ◽  
Mononuclear Cells ◽  
Peripheral Blood Mononuclear ◽  
Acid Glycoprotein ◽  
Immunodeficiency Virus ◽  
Blood Mononuclear Cells ◽  
Hiv 1

The therapeutic utility of a human immunodeficiency virus type 1 (HIV-1) protease inhibitor may depend on its intracellular concentration, which is a property of its uptake, metabolism, and/or efflux. Previous studies in our laboratory indicated that the addition of alpha 1 acid glycoprotein (alpha 1 AGP) to the medium markedly increased the amount of the drug required to limit infection in vitro. In this study, physiologically relevant concentrations of alpha 1 AGP and a radiolabeled inhibitor, A-80987, were used to determine both the uptake and activity of the agent in HIV-1-infected human peripheral blood mononuclear cells and cell lines. Both the uptake and efflux of 14C-labeled A-80987 were rapid (t1/2, < 5 min). Uptake of the drug was linearly dependent on the concentration but insensitive to the metabolic inhibitors KF, sodium cyanide, or CCCP (carbonyl cyanide m-chlorophenyl hydrazone). The amount of A-80987 which entered the cells was inversely proportional to the concentration of alpha 1 AGP (r2, 0.99) and directly proportional to the amount of extracellular non-protein-bound drug (r2, 0.99). Most importantly, the antiviral activity of the drug in HIV-1-infected peripheral blood mononuclear cells and MT-2 cells was directly related to the amount of intracellular A-80987. This study demonstrates that A-80987 binds to alpha 1 AGP, resulting in a free fraction below 10%. Cellular uptake of A-80987 is proportionally decreased in the presence of alpha 1 AGP, which results in less-than-expected antiviral activity. Importantly, we demonstrate for the first time that the inhibition of HIV protease is highly correlated with the amount of intracellular inhibitor.

scholarly journals The Dimer Initiation Sequence Stem-Loop of Human Immunodeficiency Virus Type 1 Is Dispensable for Viral Replication in Peripheral Blood Mononuclear Cells

2003 ◽  
Vol 77 (15) ◽  
pp. 8329-8335 ◽  
Author(s):  
M. K. Hill ◽  
M. Shehu-Xhilaga ◽  
S. M. Campbell ◽  
P. Poumbourios ◽  
S. M. Crowe ◽  
...  
Keyword(s):  
Human Immunodeficiency Virus ◽  
Mononuclear Cells ◽  
Wild Type ◽  
Peripheral Blood Mononuclear ◽  
Stem Loop ◽  
Immunodeficiency Virus ◽  
Blood Mononuclear Cells ◽  
T Cell Lines ◽  
Hiv 1

ABSTRACT Human immunodeficiency virus type 1 (HIV-1) contains two copies of genomic RNA that are noncovalently linked via a palindrome sequence within the dimer initiation site (DIS) stem-loop. In contrast to the current paradigm that the DIS stem or stem-loop is critical for HIV-1 infectivity, which arose from studies using T-cell lines, we demonstrate here that HIV-1 mutants with deletions in the DIS stem-loop are replication competent in peripheral blood mononuclear cells (PBMCs). The DIS mutants contained either the wild-type (5′GCGCGC3′) or an arbitrary (5′ACGCGT3′) palindrome sequence in place of the 39-nucleotide DIS stem-loop (NLCGCGCG and NLACGCGT). These DIS mutants were replication defective in SupT1 cells, concurring with the current model in which DIS mutants are replication defective in T-cell lines. All of the HIV-1 DIS mutants were replication competent in PBMCs over a 40-day infection period and had retained their respective DIS mutations at 40 days postinfection. Although the stability of the virion RNA dimer was not affected by our DIS mutations, the RNA dimers exhibited a diffuse migration profile when compared to the wild type. No defect in protein processing of the Gag and GagProPol precursor proteins was found in the DIS mutants. Our data provide direct evidence that the DIS stem-loop is dispensable for viral replication in PBMCs and that the requirement of the DIS stem-loop in HIV-1 replication is cell type dependent.

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