scholarly journals Lentiviral Nef Proteins Manipulate T Cells in a Subset-Specific Manner

2014 ◽  
Vol 89 (4) ◽  
pp. 1986-2001 ◽  
Author(s):  
Hangxing Yu ◽  
Mohammad Khalid ◽  
Anke Heigele ◽  
Jan Schmökel ◽  
Shariq M. Usmani ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
Viral Replication ◽  
Cell Subset ◽  
T Cell Subsets ◽  
Immunodeficiency Virus ◽  
Primate Lentiviruses ◽  
Selective Preservation ◽  
Hiv 1

ABSTRACTThe role of the accessory viral Nef protein as a multifunctional manipulator of the host cell that is required for effective replication of human immunodeficiency virus (HIV) and simian immunodeficiency virus (SIV)in vivois well established. It is unknown, however, whether Nef manipulates all or just specific subsets of CD4+T cells, which are the main targets of virus infection and differ substantially in their state of activation and importance for a functional immune system. Here, we analyzed the effect of Nef proteins differing in their T cell receptor (TCR)-CD3 downmodulation function in HIV-infected human lymphoid aggregate cultures and peripheral blood mononuclear cells. We found that Nef efficiently downmodulates TCR-CD3 in naive and memory CD4+T cells and protects the latter against apoptosis. In contrast, highly proliferative CD45RA+CD45RO+CD4+T cells were main producers of infectious virus but largely refractory to TCR-CD3 downmodulation. Such T cell subset-specific differences were also observed for Nef-mediated modulation of CD4 but not for enhancement of virion infectivity. Our results indicate that Nef predominantly modulates surface receptors on CD4+T cell subsets that are not already fully permissive for viral replication. As a consequence, Nef-mediated downmodulation of TCR-CD3, which distinguishes most primate lentiviruses from HIV type 1 (HIV-1) and itsvpu-containing simian precursors, may promote a selective preservation of central memory CD4+T cells, which are critical for the maintenance of a functional immune system.IMPORTANCEThe Nef proteins of human and simian immunodeficiency viruses manipulate infected CD4+T cells in multiple ways to promote viral replication and immune evasionin vivo. Here, we show that some effects of Nef are subset specific. Downmodulation of CD4 and TCR-CD3 is highly effective in central memory CD4+T cells, and the latter Nef function protects this T cell subset against apoptosis. In contrast, highly activated/proliferating CD4+T cells are largely refractory to receptor downmodulation but are main producers of infectious HIV-1. Nef-mediated enhancement of virion infectivity, however, was observed in all T cell subsets examined. Our results provide new insights into how primate lentiviruses manipulate their target cells and suggest that the TCR-CD3 downmodulation function of Nef may promote a selective preservation of memory CD4+T cells, which are critical for immune function, but has little effect on activated/proliferating CD4+T cells, which are the main targets for viral replication.

scholarly journals Cytopathic Effects of Non-Syncytium-Inducing and Syncytium-Inducing Human Immunodeficiency Virus Type 1 Variants on Different CD4+-T-Cell Subsets Are Determined Only by Coreceptor Expression

2001 ◽  
Vol 75 (21) ◽  
pp. 10455-10459 ◽  
Author(s):  
David Kwa ◽  
Jose Vingerhoed ◽  
Brigitte Boeser-Nunnink ◽  
Silvia Broersen ◽  
Hanneke Schuitemaker
Keyword(s):  
Human Immunodeficiency Virus ◽  
T Cells ◽  
T Cell ◽  
Human Immunodeficiency Virus Type ◽  
Virus Type ◽  
Cell Subset ◽  
T Cell Subsets ◽  
Immunodeficiency Virus ◽  
Hiv 1

ABSTRACT In peripheral blood mononuclear cells, syncytium-inducing (SI) human immunodeficiency virus type 1 (HIV-1) infected and depleted all CD4+ T cells, including naive T cells. Non-SI HIV-1 infected and depleted only the CCR5-expressing T-cell subset. This may explain the accelerated CD4 cell loss after SI conversion in vivo.

scholarly journals Discordance between Frequency of Human Immunodeficiency Virus Type 1 (HIV-1)-Specific Gamma Interferon-Producing CD4+ T Cells and HIV-1-Specific Lymphoproliferation in HIV-1-Infected Subjects with Active Viral Replication

2002 ◽  
Vol 76 (12) ◽  
pp. 5925-5936 ◽  
Author(s):  
B. E. Palmer ◽  
E. Boritz ◽  
N. Blyveis ◽  
C. C. Wilson
Keyword(s):  
T Cells ◽  
T Cell ◽  
Viral Replication ◽  
Th Cell ◽  
Immunodeficiency Virus ◽  
Active Viral Replication ◽  
Hiv 1

ABSTRACT One hallmark of uncontrolled, chronic human immunodeficiency virus type 1 (HIV-1) infection is the absence of strong HIV-1-specific, CD4+ T-cell-proliferative responses, yet the mechanism underlying this T helper (Th)-cell defect remains controversial. To better understand the impact of HIV-1 replication on Th-cell function, we compared the frequency of CD4+ Th-cell responses based on production of gamma interferon to lymphoproliferative responses directed against HIV-1 proteins in HIV-1-infected subjects with active in vivo viral replication versus those on suppressed highly active antiretroviral therapy (HAART). No statistically significant differences in the frequencies of cytokine-secreting, HIV-1-specific CD4+ T cells between the donor groups were found, despite differences in viral load and treatment status. However, HIV-1-specific lymphoproliferative responses were significantly greater in the subjects with HAART suppression than in subjects with active viral replication. Similar levels of HIV-1 RNA were measured in T-cell cultures stimulated with HIV-1 antigens regardless of donor in vivo viral loads, but only HIV-1-specific CD4+ T cells from subjects with HAART suppression proliferated in vitro, suggesting that HIV-1 replication in vitro does not preclude HIV-1-specific lymphoproliferation. This study demonstrates a discordance between the frequency and proliferative capacity of HIV-1-specific CD4+ T cells in subjects with ongoing in vivo viral replication and suggests that in vivo HIV-1 replication contributes to the observed defect in HIV-1-specific CD4+ T-cell proliferation.

scholarly journals LFA-1 Is a Key Determinant for Preferential Infection of Memory CD4+ T Cells by Human Immunodeficiency Virus Type 1

2005 ◽  
Vol 79 (21) ◽  
pp. 13714-13724 ◽  
Author(s):  
Mélanie R. Tardif ◽  
Michel J. Tremblay
Keyword(s):  
Human Immunodeficiency Virus ◽  
T Cells ◽  
Human Immunodeficiency Virus Type ◽  
Virus Type ◽  
Cell Subset ◽  
T Cell Subsets ◽  
Virus Infectivity ◽  
Immunodeficiency Virus ◽  
Hiv 1

ABSTRACT Memory CD4+ T cells are considered a stable latent reservoir for human immunodeficiency virus type 1 (HIV-1) and a barrier to eradication of this retroviral infection in patients under therapy. It has been shown that memory CD4+ T cells are preferentially infected with HIV-1, but the exact mechanism(s) responsible for this higher susceptibility remains obscure. Previous findings indicate that incorporation of host-derived intercellular adhesion molecule 1 (ICAM-1) in HIV-1 increases virus infectivity. To measure the putative involvement of virus-anchored ICAM-1 in the preferential infection of memory cells by HIV-1, quiescent and activated naive and memory T-cell subsets were exposed to isogenic virions either lacking or bearing ICAM-1. Memory CD4+ T cells were found to be more susceptible than naive CD4+ T cells to infection with ICAM-1-bearing virions, as exemplified by a more important virus replication, an increase in integrated viral DNA copies, and a more efficient entry process. Interactions between virus-associated host ICAM-1 and cell surface LFA-1 under a cluster formation seem to be responsible for the preferential HIV-1 infection of the memory cell subset. Altogether, these data shed light on a potential mechanism by which HIV-1 preferentially targets long-lived memory CD4+ T cells.

scholarly journals T-Cell Subsets That Harbor Human Immunodeficiency Virus (HIV) In Vivo: Implications for HIV Pathogenesis

2004 ◽  
Vol 78 (3) ◽  
pp. 1160-1168 ◽  
Author(s):  
Jason M. Brenchley ◽  
Brenna J. Hill ◽  
David R. Ambrozak ◽  
David A. Price ◽  
Francisco J. Guenaga ◽  
...  
Keyword(s):  
Human Immunodeficiency Virus ◽  
T Cells ◽  
T Cell ◽  
Ex Vivo ◽  
T Cell Subsets ◽  
Cell Infection ◽  
Immunodeficiency Virus ◽  
Polychromatic Flow Cytometry ◽  
Underlying Mechanisms

ABSTRACT Identification of T-cell subsets that are infected in vivo is essential to understanding the pathogenesis of human immunodeficiency virus (HIV) disease; however, this goal has been beset with technical challenges. Here, we used polychromatic flow cytometry to sort multiple T-cell subsets to 99.8% purity, followed by quantitative PCR to quantify HIV gag DNA directly ex vivo. We show that resting memory CD4+ T cells are the predominantly infected cells but that terminally differentiated memory CD4+ T cells contain 10-fold fewer copies of HIV DNA. Memory CD8+ T cells can also be infected upon upregulation of CD4; however, this is infrequent and HIV-specific CD8+ T cells are not infected preferentially. Naïve CD4+ T-cell infection is rare and principally confined to those peripheral T cells that have proliferated. Furthermore, the virus is essentially absent from naïve CD8+ T cells, suggesting that the thymus is not a major source of HIV-infected T cells in the periphery. These data illuminate the underlying mechanisms that distort T-cell homeostasis in HIV infection.

scholarly journals HIV-1-Specific CD11c+ CD8+ T Cells Display Low PD-1 Expression and Strong Anti-HIV-1 Activity

2021 ◽  
Vol 12 ◽  
Author(s):  
An-Liang Guo ◽  
Jin-Fang Zhao ◽  
Lin Gao ◽  
Hui-Huang Huang ◽  
Ji-Yuan Zhang ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
Cell Subset ◽  
T Cell Subsets ◽  
Hla Dr ◽  
Tnf Α ◽  
Treatment Naïve ◽  
Vitro Analysis ◽  
Hiv 1

Exhaustion of HIV-1-specific CD8+ T cells prevents optimal control of HIV-1 infection. Identifying unconventional CD8+ T cell subsets to effectively control HIV-1 replication is vital. In this study, the role of CD11c+ CD8+ T cells during HIV-1 infection was evaluated. The frequencies of CD11c+ CD8+ T cells significantly increased and were negatively correlated with viral load in HIV-1-infected treatment-naïve patients. HIV-1-specific cells were enriched more in CD11c+ CD8+ T cells than in CD11c- CD8+ T cells, which could be induced by HIV-1-derived overlapping peptides, marking an HIV-1-specific CD8+ T cell population. This subset expressed higher levels of activating markers (CD38 and HLA-DR), cytotoxic markers (granzyme B, perforin, and CD107a), and cytokines (IL-2 and TNF-α), with lower levels of PD-1 compared to the CD11c- CD8+ T cell subset. In vitro analysis verified that CD11c+ CD8+ T cells displayed a stronger HIV-1-specific killing capacity than the CD11c- counterparts. These findings indicate that CD11c+ CD8+ T cells have potent immunotherapeutic efficacy in controlling HIV-1 infection.

Apoptotic Pathways of Human Regulatory T Cells in Chronic Graft Versus Host Disease (cGVHD) After Allogeneic Hematopoietic Stem Cell Transplantation (HSCT)

Blood ◽  
2012 ◽  
Vol 120 (21) ◽  
pp. 225-225
Author(s):  
Kazuyuki Murase ◽  
Yutaka Kawano ◽  
Jeremy Ryan ◽  
Ken-ichi Matsuoka ◽  
Gregory Bascug ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
Cd8 T Cells ◽  
Low Dose ◽  
Cell Subset ◽  
Mitochondrial Pathway ◽  
T Cell Subsets ◽  
T Cell Subset ◽  
Mitochondrial Membrane Depolarization

Abstract Abstract 225 CD4+CD25+Foxp3+ regulatory T cells (Treg) are known to play a central role in the maintenance of self-tolerance and immune homeostasis. After allogeneic stem cell transplantation, impaired recovery of Treg is associated with the development of cGVHD. Interleukin-2 (IL-2) is a critical regulator of Treg development, expansion and survival and lack of IL-2 results in Treg deficiency. In patients with cGVHD, we previously demonstrated that Treg proliferate at high levels but this subset is also highly susceptible to apoptosis leading to inadequate Treg numbers (Matsuoka et al. JCI 2010). We also reported that low-dose IL-2 administration resulted in selective expansion of Treg in vivo and clinical improvement of cGVHD (Koreth et al. NEJM 2011). To identify mechanisms responsible for increased Treg susceptibility to apoptosis in cGVHD we used a new flow cytometry-based assay to measure mitochondrial membrane depolarization in response to a panel of pro-apoptotic BH3 peptides (BIM, BID, BAD, NOXA, PUMA, BMF, HRK). This assessment allowed us to compare BH3 peptide-induced mitochondrial membrane depolarization (“priming”) in different T cell subsets, including CD4 Treg, conventional CD4 T cells (CD4 Tcon), and CD8 T cells. Expression of Bcl-2, CD95 and Ki67 were also studied in each T cell subset. We studied peripheral blood samples from 36 patients with hematologic malignancies (median age 59 yr) who are > 2 years post HSCT (27 patients with cGVHD and 9 patients without cGVHD) and 15 patients who received daily subcutaneous IL-2 for 8 weeks for treatment of steroid-refractory cGvHD. Severity of cGVHD was classified according to NIH criteria. In patients without cGVHD, BH3 priming was similar in all 3 T cell subsets (CD4 Treg, CD4 Tcon and CD8). In patients with cGVHD, CD4 Treg were more primed than CD4 Tcon when challenged with BIM, BAD, PUMA, BMF and the combination of BAD + NOXA peptides (p<0.01 – 0.0001). Treg were more primed than CD8 T cells when challenged with PUMA peptide (p<0.0001), but priming in Treg and CD8 T cells was similar for other BH3 peptides in patients with cGVHD. We also compared BH3 priming of each T cell subset in patients with different grades of cGVHD. When challenged with BH3 peptides, Treg, Tcon and CD8 T cells were less primed in patients with severe cGVHD. In patients with cGVHD, Treg expressed higher levels of Ki-67, higher levels of CD95 and lower levels of Bcl-2 than Tcon. Expression of CD95 did not vary with severity of GVHD in any T cell subset, but expression of Bcl-2 was significantly increased in all subsets in patients with severe cGVHD. Increased BH3 priming and high expression of CD95 indicate that Treg are more susceptible to apoptosis than Tcon in cGVHD. However, both Treg and Tcon become less primed and Bcl-2 levels increase in severe cGVHD suggesting that these cells are less susceptible to mitochondrial pathway apoptosis. Since the total number of Treg and Tcon are significantly reduced in patients with cGVHD, these findings suggest that the remaining circulating cells are relatively resistant to mitochondrial pathway apoptosis. CD95 expression in Treg remains high indicating no change in death receptor pathway apoptosis. Daily treatment with low-dose IL-2 for 8 weeks selectively expands Treg in vivo in patients with severe cGVHD. As the number of Treg increase, BH3 profiling shows that these cells gradually become more primed and therefore more susceptible to mitochondrial pathway apoptosis. Taken together, these studies help define the complex and distinct pathways that regulate survival in different T cell subsets and changes in these pathways that occur in patients with chronic GVHD. These pathways play important roles in the maintenance of T cell homeostasis and targeting these complex pathways can provide new opportunities to promote immune tolerance after allogeneic HSCT. Disclosures: No relevant conflicts of interest to declare.

scholarly journals Displacement of SATB1-Bound Histone Deacetylase 1 Corepressor by the Human Immunodeficiency Virus Type 1 Transactivator Induces Expression of Interleukin-2 and Its Receptor in T Cells

2005 ◽  
Vol 25 (5) ◽  
pp. 1620-1633 ◽  
Author(s):  
P. Pavan Kumar ◽  
Prabhat Kumar Purbey ◽  
Dyavar S. Ravi ◽  
Debashis Mitra ◽  
Sanjeev Galande
Keyword(s):  
Human Immunodeficiency Virus ◽  
T Cells ◽  
T Cell ◽  
Histone Deacetylase ◽  
Interleukin 2 ◽  
Histone Deacetylase 1 ◽  
Immunodeficiency Virus ◽  
Hiv 1

ABSTRACT One hallmark of human immunodeficiency virus type 1 (HIV-1) infection is the dysregulation of cytokine gene expression in T cells. Transfection of T cells with human T-cell leukemia type 1 or 2 transactivator results in the induction of the T-cell-restricted cytokine interleukin-2 (IL-2) and its receptor (IL-2Rα). However, no T-cell-specific factor(s) has been directly linked with the regulation of IL-2 and IL-2Rα transcription by influencing the promoter activity. Thymocytes from SATB1 (special AT-rich sequence binding protein 1) knockout mice have been shown to ectopically express IL-2Rα, suggesting involvement of SATB1 in its negative regulation. Here we show that SATB1, a T-cell-specific global gene regulator, binds to the promoters of human IL-2 and IL-2Rα and recruits histone deacetylase 1 (HDAC1) in vivo. SATB1 also interacts with Tat in HIV-1-infected T cells. The functional interaction between HIV-1 Tat and SATB1 requires its PDZ-like domain, and the binding of the HDAC1 corepressor occurs through the same. Furthermore, Tat competitively displaces HDAC1 that is bound to SATB1, leading to increased acetylation of the promoters in vivo. Transduction with SATB1 interaction-deficient soluble Tat (Tat 40-72) and reporter assays using a transactivation-negative mutant (C22G) of Tat unequivocally demonstrated that the displacement of HDAC1 itself is sufficient for derepression of these promoters in vivo. These results suggest a novel mechanism by which HIV-1 Tat might overcome SATB1-mediated repression in T cells.

scholarly journals Both Memory and CD45RA+/CD62L+ Naive CD4+ T Cells Are Infected in Human Immunodeficiency Virus Type 1-Infected Individuals

1999 ◽  
Vol 73 (8) ◽  
pp. 6430-6435 ◽  
Author(s):  
Mario A. Ostrowski ◽  
Tae-Wook Chun ◽  
Shawn J. Justement ◽  
Ivette Motola ◽  
Michael A. Spinelli ◽  
...  
Keyword(s):  
Human Immunodeficiency Virus ◽  
T Cells ◽  
T Cell ◽  
Human Immunodeficiency Virus Type ◽  
Virus Type ◽  
T Cell Subsets ◽  
Viral Reservoir ◽  
Immunodeficiency Virus ◽  
Hiv 1

ABSTRACT Cellular activation is critical for the propagation of human immunodeficiency virus type 1 (HIV-1) infection. It has been suggested that truly naive CD4+ T cells are resistant to productive HIV-1 infection because of their constitutive resting state. Memory and naive CD4+ T-cell subsets from 11 HIV-1-infected individuals were isolated ex vivo by a combination of magnetic bead depletion and fluorescence-activated cell sorting techniques with stringent criteria of combined expression of CD45RA and CD62L to identify naive CD4+ T-cell subsets. In all patients HIV-1 provirus could be detected within naive CD45RA+/CD62L+ CD4+ T cells; in addition, replication-competent HIV-1 was isolated from these cells upon CD4+ T-cell stimulation in tissue cultures. Memory CD4+ T cells had a median of fourfold more replication-competent virus and a median of sixfold more provirus than naive CD4+ T cells. Overall, there was a median of 16-fold more integrated provirus identified in memory CD4+ T cells than in naive CD4+ T cells within a given patient. Interestingly, there was a trend toward equalization of viral loads in memory and naive CD4+ T-cell subsets in those patients who harbored CXCR4-using (syncytium-inducing) viruses. Within any given patient, there was no selective usage of a particular coreceptor by virus isolated from memory versus naive CD4+ T cells. Our findings suggest that naive CD4+ T cells may be a significant viral reservoir for HIV, particularly in those patients harboring CXCR4-using viruses.

scholarly journals Naïve T-Cell Depletion Related to Infection by X4 Human Immunodeficiency Virus Type 1 in Poor Immunological Responders to Highly Active Antiretroviral Therapy

2006 ◽  
Vol 80 (20) ◽  
pp. 10229-10236 ◽  
Author(s):  
Pierre Delobel ◽  
Marie-Thérèse Nugeyre ◽  
Michelle Cazabat ◽  
Karine Sandres-Sauné ◽  
Christophe Pasquier ◽  
...  
Keyword(s):  
Human Immunodeficiency Virus ◽  
T Cells ◽  
T Cell ◽  
Antiretroviral Therapy ◽  
Highly Active Antiretroviral Therapy ◽  
T Cell Subsets ◽  
Highly Active ◽  
The Poor ◽  
Immunodeficiency Virus ◽  
Hiv 1

ABSTRACT The reasons for poor CD4+ T-cell recovery in some human immunodeficiency virus (HIV)-infected subjects despite effective highly active antiretroviral therapy (HAART) remain unclear. We recently reported that CXCR4-using (X4) HIV-1 could be gradually selected in cellular reservoirs during sustained HAART. Because of the differential expression of HIV-1 coreceptors CCR5 and CXCR4 on distinct T-cell subsets, the residual replication of R5 and X4 viruses could have different impacts on T-cell homeostasis during immune reconstitution on HAART. We examined this hypothesis and the mechanisms of CD4+ T-cell restoration by comparing the virological and immunological features of 15 poor and 15 good immunological responders to HAART. We found a high frequency of X4 viruses in the poor immunological responders. But the levels of intrathymic proliferation of the two groups were similar regardless of whether they were infected by R5 or X4 virus. The frequency of recent thymic emigrants in the poor immunological responders was also similar to that found in the good immunological responders, despite their reduced numbers of naïve CD4+ T cells. Our data, rather, suggest that the naïve T-cell compartment is drained by a high rate of mature naïve cell loss in the periphery due to bystander apoptosis or activation-induced differentiation. X4 viruses could play a role in the depletion of naïve T cells in poor immunological responders to HAART by triggering persistent T-cell activation and bystander apoptosis via gp120-CXCR4 interactions.

scholarly journals Single Cell RNA-Sequencing-based Analysis of CD4+ T-Cell Subset-Specific Susceptibility to Transcriptional Modulation by HIV-1 Latency-Reversing Agents

2020 ◽  
Author(s):  
Julia Kazmierski ◽  
Dylan Postmus ◽  
Emanuel Wyler ◽  
Cornelius Fischer ◽  
Jenny Jansen ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
Single Cell ◽  
Hdac Inhibitors ◽  
Cell Subset ◽  
T Cell Subset ◽  
Single Cell Rna Sequencing ◽  
Hiv 1 ◽  
Reversing Agents

AbstractShock-and-kill is one of the conceptually most advanced strategy towards establishment of an HIV-1 cure. Treatment with latency-reversing agents (LRAs), including histone deacetylase inhibitors with chromatin-remodeling capabilities, combined with anti-retroviral therapy, reactivates HIV-1 transcription in vivo. However, LRA treatment fails to significantly reduce the HIV-1 reservoir in HIV-1-positive individuals, indicating that it is probably insufficient to eliminate latently infected cells. The global and T-cell subset-specific impact of individual LRAs on the transcriptome of CD4+ T-cells, the main HIV-1 reservoir containing cell type in vivo, remains understudied. Here, using single cell RNA-sequencing, we characterize LRA treatment-induced alterations of CD4+ T-cell subset composition and of subpopulation-specific transcriptomes, using Vorinostat and Panobinostat as two prototypic HDAC inhibitors. Ex vivo exposure of CD4+ T-cells from an aviremic HIV-1-positive individual to Panobinostat markedly reduced the percentage of TREG cells. Furthermore, it altered expression of a multitude of interferon-regulated genes, resulting in suppression of several well-characterized antiviral genes, and in enhancement of selected interferon-regulated genes with proviral activities. These changes were most pronounced in TN, TCM, TTM and TEM, and less pronounced in TREG. Exposure to Vorinostat resulted in a comparably mild change of cellular transcriptomic profile, regarding both the number of deregulated genes and their fold change of expression. Nevertheless, selected interferon-regulated genes exhibited a subset-specific expression profile upon Vorinostat treatment. Finally, some genes were deregulated by both treatments in a subset-specific manner. We conclude that treatment by both individual HDAC inhibitors induces an overall proviral milieu in CD4+ T-cells subsets. While this proviral state might be favorable for efficient HIV-1 reactivation, we hypothesize that it may impede the instruction of activation of cellular and adaptive immunity required for effective killing of reactivated cells.

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