scholarly journals Large number of rebounding/founder HIV variants emerge from multifocal infection in lymphatic tissues after treatment interruption

2015 ◽  
Vol 112 (10) ◽  
pp. E1126-E1134 ◽  
Author(s):  
Meghan K. Rothenberger ◽  
Brandon F. Keele ◽  
Stephen W. Wietgrefe ◽  
Courtney V. Fletcher ◽  
Gregory J. Beilman ◽  
...  
Keyword(s):  
Peripheral Blood ◽  
Mononuclear Cells ◽  
Single Gene ◽  
Virus Production ◽  
Lymphoid Tissues ◽  
Anatomic Site ◽  
Peripheral Blood Mononuclear ◽  
Latently Infected ◽  
Infected Cells ◽  
Recrudescent Infection

Antiretroviral therapy (ART) suppresses HIV replication in most individuals but cannot eradicate latently infected cells established before ART was initiated. Thus, infection rebounds when treatment is interrupted by reactivation of virus production from this reservoir. Currently, one or a few latently infected resting memory CD4 T cells are thought be the principal source of recrudescent infection, but this estimate is based on peripheral blood rather than lymphoid tissues (LTs), the principal sites of virus production and persistence before initiating ART. We, therefore, examined lymph node (LN) and gut-associated lymphoid tissue (GALT) biopsies from fully suppressed subjects, interrupted therapy, monitored plasma viral load (pVL), and repeated biopsies on 12 individuals as soon as pVL became detectable. Isolated HIV RNA-positive (vRNA+) cells were detected by in situ hybridization in LTs obtained before interruption in several patients. After interruption, multiple foci of vRNA+ cells were detected in 6 of 12 individuals as soon as pVL was measureable and in some subjects, in more than one anatomic site. Minimal estimates of the number of rebounding/founder (R/F) variants were determined by single-gene amplification and sequencing of viral RNA or DNA from peripheral blood mononuclear cells and plasma obtained at or just before viral recrudescence. Sequence analysis revealed a large number of R/F viruses representing recrudescent viremia from multiple sources. Together, these findings are consistent with the origins of recrudescent infection by reactivation from many latently infected cells at multiple sites. The inferred large pool of cells and sites to rekindle recrudescent infection highlights the challenges in eradicating HIV.

scholarly journals Toll-Like Receptor 7 Agonist GS-9620 Induces HIV Expression and HIV-Specific Immunity in Cells from HIV-Infected Individuals on Suppressive Antiretroviral Therapy

2017 ◽  
Vol 91 (8) ◽  
Author(s):  
Angela Tsai ◽  
Alivelu Irrinki ◽  
Jasmine Kaur ◽  
Tomas Cihlar ◽  
George Kukolj ◽  
...  
Keyword(s):  
Antiretroviral Therapy ◽  
Mononuclear Cells ◽  
Antiviral Immunity ◽  
Type I ◽  
Toll Like Receptor ◽  
Peripheral Blood Mononuclear ◽  
Effector Functions ◽  
Latently Infected ◽  
Infected Cells ◽  
Latent Hiv

ABSTRACT Antiretroviral therapy can suppress HIV replication to undetectable levels but does not eliminate latent HIV, thus necessitating lifelong therapy. Recent efforts to target this persistent reservoir have focused on inducing the expression of latent HIV so that infected cells may be recognized and eliminated by the immune system. Toll-like receptor (TLR) activation stimulates antiviral immunity and has been shown to induce HIV from latently infected cells. Activation of TLR7 leads to the production of several stimulatory cytokines, including type I interferons (IFNs). In this study, we show that the selective TLR7 agonist GS-9620 induced HIV in peripheral blood mononuclear cells (PBMCs) from HIV-infected individuals on suppressive antiretroviral therapy. GS-9620 increased extracellular HIV RNA 1.5- to 2-fold through a mechanism that required type I IFN signaling. GS-9620 also activated HIV-specific T cells and enhanced antibody-mediated clearance of HIV-infected cells. Activation by GS-9620 in combination with HIV peptide stimulation increased CD8 T cell degranulation, production of intracellular cytokines, and cytolytic activity. T cell activation was again dependent on type I IFNs produced by plasmacytoid dendritic cells. GS-9620 induced phagocytic cell maturation and improved effector-mediated killing of HIV-infected CD4 T cells by the HIV envelope-specific broadly neutralizing antibody PGT121. Collectively, these data show that GS-9620 can activate HIV production and improve the effector functions that target latently infected cells. GS-9620 may effectively complement orthogonal therapies designed to stimulate antiviral immunity, such as therapeutic vaccines or broadly neutralizing antibodies. Clinical studies are under way to determine if GS-9620 can target HIV reservoirs. IMPORTANCE Though antiretroviral therapies effectively suppress viral replication, they do not eliminate integrated proviral DNA. This stable intermediate of viral infection is persistently maintained in reservoirs of latently infected cells. Consequently, lifelong therapy is required to maintain viral suppression. Ultimately, new therapies that specifically target and eliminate the latent HIV reservoir are needed. Toll-like receptor agonists are potent enhancers of innate antiviral immunity that can also improve the adaptive immune response. Here, we show that a highly selective TLR7 agonist, GS-9620, activated HIV from peripheral blood mononuclear cells isolated from HIV-infected individuals with suppressed infection. GS-9620 also improved immune effector functions that specifically targeted HIV-infected cells. Previously published studies on the compound in other chronic viral infections show that it can effectively induce immune activation at safe and tolerable clinical doses. Together, the results of these studies suggest that GS-9620 may be useful for treating HIV-infected individuals on suppressive antiretroviral therapy.

scholarly journals Establishment of a Novel Humanized Mouse Model To Investigate In Vivo Activation and Depletion of Patient-Derived HIV Latent Reservoirs

2019 ◽  
Vol 93 (6) ◽  
Author(s):  
Nina C. Flerin ◽  
Ariola Bardhi ◽  
Jian Hua Zheng ◽  
Maria Korom ◽  
Joy Folkvord ◽  
...  
Keyword(s):  
Mouse Model ◽  
Hiv Infection ◽  
Mononuclear Cells ◽  
Systemic Infection ◽  
Humanized Mouse Model ◽  
Peripheral Blood Mononuclear ◽  
Immunodeficient Mice ◽  
Latently Infected ◽  
Infected Cells

ABSTRACT Curing HIV infection has been thwarted by the persistent reservoir of latently infected CD4+ T cells, which reinitiate systemic infection after antiretroviral therapy (ART) interruption. To evaluate reservoir depletion strategies, we developed a novel preclinical in vivo model consisting of immunodeficient mice intrasplenically injected with peripheral blood mononuclear cells (PBMC) from long-term ART-suppressed HIV-infected donors. In the absence of ART, these mice developed rebound viremia which, 2 weeks after PBMC injection, was 1,000-fold higher (mean = 9,229,281 HIV copies/ml) in mice injected intrasplenically than in mice injected intraperitoneally (mean = 6,838 HIV copies/ml) or intravenously (mean = 591 HIV copies/ml). One week after intrasplenic PBMC injection, in situ hybridization of the spleen demonstrated extensive disseminated HIV infection, likely initiated from in vivo-reactivated primary latently infected cells. The time to viremia was delayed significantly by treatment with a broadly neutralizing antibody, 10-1074, compared to treatment with 10-1074-FcRnull, suggesting that 10-1074 mobilized Fc-mediated effector mechanisms to deplete the replication-competent reservoir. This was supported by phylogenetic analysis of Env sequences from viral-outgrowth cultures and untreated, 10-1074-treated, or 10-1074-FcRnull-treated mice. The predominant sequence cluster detected in viral-outgrowth cultures and untreated mouse plasma was significantly reduced in the plasma of 10-1074-treated mice, whereas two new clusters emerged that were not detected in viral-outgrowth cultures or plasma from untreated mice. These new clusters lacked mutations associated with 10-1074 resistance. Taken together, these data indicated that 10-1074 treatment depletes the reservoir of latently infected cells harboring replication competent HIV. Furthermore, this mouse model represents a new in vivo approach for the preclinical evaluation of new HIV cure strategies. IMPORTANCE Sustained remission of HIV infection is prevented by a persistent reservoir of latently infected cells capable of reinitiating systemic infection and viremia. To evaluate strategies to reactivate and deplete this reservoir, we developed and characterized a new humanized mouse model consisting of highly immunodeficient mice intrasplenically injected with peripheral blood mononuclear cells from long-term ART-suppressed HIV-infected donors. Reactivation and dissemination of HIV infection was visualized in the mouse spleens in parallel with the onset of viremia. The applicability of this model for evaluating reservoir depletion treatments was demonstrated by establishing, through delayed time to viremia and phylogenetic analysis of plasma virus, that treatment of these humanized mice with a broadly neutralizing antibody, 10-1074, depleted the patient-derived population of latently infected cells. This mouse model represents a new in vivo approach for the preclinical evaluation of new HIV cure strategies.

scholarly journals The ND10 Complex Represses Lytic Human Herpesvirus 6A Replication and Promotes Silencing of the Viral Genome

Viruses ◽  
2018 ◽  
Vol 10 (8) ◽  
pp. 401 ◽  
Author(s):  
Anirban Sanyal ◽  
Nina Wallaschek ◽  
Mandy Glass ◽  
Louis Flamand ◽  
Darren Wight ◽  
...  
Keyword(s):  
Mononuclear Cells ◽  
Human Herpesvirus ◽  
Virus Genome ◽  
Lytic Replication ◽  
Peripheral Blood Mononuclear ◽  
Latently Infected ◽  
Infected Cells ◽  
T Cell Lines ◽  
Virus Genomes

Human herpesvirus 6A (HHV-6A) replicates in peripheral blood mononuclear cells (PBMCs) and various T-cell lines in vitro. Intriguingly, the virus can also establish latency in these cells, but it remains unknown what influences the decision between lytic replication and the latency of the virus. Incoming virus genomes are confronted with the nuclear domain 10 (ND10) complex as part of an intrinsic antiviral response. Most herpesviruses can efficiently subvert ND10, but its role in HHV-6A infection remains poorly understood. In this study, we investigated if the ND10 complex affects HHV-6A replication and contributes to the silencing of the virus genome during latency. We could demonstrate that ND10 complex was not dissociated upon infection, while the number of ND10 bodies was reduced in lytically infected cells. Virus replication was significantly enhanced upon knock down of the ND10 complex using shRNAs against its major constituents promyelocytic leukemia protein (PML), hDaxx, and Sp100. In addition, we could demonstrate that viral genes are more efficiently silenced in the presence of a functional ND10 complex. Our data thereby provides the first evidence that the cellular ND10 complex plays an important role in suppressing HHV-6A lytic replication and the silencing of the virus genome in latently infected cells.

scholarly journals Quantitative Analysis of Latent Human Cytomegalovirus

1999 ◽  
Vol 73 (6) ◽  
pp. 4806-4812 ◽  
Author(s):  
Barry Slobedman ◽  
Edward S. Mocarski
Keyword(s):  
Bone Marrow ◽  
Peripheral Blood ◽  
Copy Number ◽  
Mononuclear Cells ◽  
Latent Infection ◽  
Natural Infection ◽  
Viral Genomes ◽  
Reverse Transcription Pcr ◽  
Latently Infected ◽  
Infected Cells

ABSTRACT Cytomegalovirus latency depends on an interaction with hematopoietic cells in bone marrow and peripheral blood. The distribution of viral DNA was investigated by PCR-driven in situ hybridization (PCR-ISH), and the number of viral genomes per cell was estimated by quantitative competitive PCR during both experimental and natural latent infection. During experimental latent infection of cultured granulocyte-macrophage progenitors, the viral genome was detected in >90% of cells at a copy number of 1 to 8 viral genomes per cell. During natural infection, viral genomes were detected in 0.004 to 0.01% of mononuclear cells from granulocyte colony-stimulating factor-mobilized peripheral blood or bone marrow from seropositive donors, at a copy number of 2 to 13 genomes per infected cell. When evaluated by reverse transcription–PCR-ISH, only a small proportion of experimentally infected cells (approximately 2%) had detectable latent transcripts. This investigation identifies the small percentage of bone marrow-derived mononuclear cells that become latently infected during natural infection and suggests that latency may proceed in some cells that fail to encode currently identified latent transcripts.

scholarly journals Changes in CD4+, CD8+, CD4+ CD8+, and Immunoglobulin M-Positive Peripheral Blood Mononuclear Cells of Postweaning Multisystemic Wasting Syndrome-Affected Pigs and Age-Matched Uninfected Wasted and Healthy Pigs Correlate with Lesions and Porcine Circovirus Type 2 Load in Lymphoid Tissues

2002 ◽  
Vol 9 (2) ◽  
pp. 236-242 ◽  
Author(s):  
Laila Darwich ◽  
Joaquim Segalés ◽  
Mariano Domingo ◽  
Enric Mateu
Keyword(s):  
Peripheral Blood ◽  
Mononuclear Cells ◽  
Porcine Circovirus Type ◽  
Postweaning Multisystemic Wasting Syndrome ◽  
Immunoglobulin M ◽  
Porcine Circovirus ◽  
Lymphoid Tissues ◽  
Peripheral Blood Mononuclear ◽  
Wasting Syndrome

ABSTRACT Forty-one 8- to 12-week-old wasted pigs were selected from several conventional farms with histories of postweaning multisystemic wasting syndrome (PMWS) and classified into two groups according to their porcine circovirus type 2 (PCV2) infection status, as determined by in situ hybridization (ISH). Twenty-four pigs tested positive for PCV2 (PCV2-positive group), while 17 pigs tested negative for PCV2 (PCV2-negative group). In addition, eight uninfected healthy pigs from an experimental farm were used as controls. Heparinized blood samples were taken to obtain peripheral blood mononuclear cells. The CD4+, CD8+, CD4+ CD8+ (double-positive [DP]), and immunoglobulin M-positive (IgM+) cell subsets were analyzed by flow cytometry with appropriate monoclonal antibodies. Histopathological studies were done to evaluate the apparent degrees of lymphocyte depletion in different lymphoid organs (superficial inguinal and mesenteric lymph nodes, Peyer's patches, tonsils, and spleen) and to determine the viral load of the PCV2 genome by using an ISH technique. Animals of the PCV2-positive group showed a significant downshift of the CD8+ and DP cell subsets compared to the other groups (P < 0.05). Moreover, in PCV2-positive pigs, the amount of PCV2 genome in lymphoid tissues was related to the degree of cell depletion in those tissues (P < 0.05) as well as to the relative decrease in IgM+ and CD8+ cells in peripheral blood. These data support the notion that PCV2-positive pigs might have an impaired immune response.

scholarly journals B Cells of HIV-1–Infected Patients Bind Virions through Cd21–Complement Interactions and Transmit Infectious Virus to Activated T Cells

2000 ◽  
Vol 192 (5) ◽  
pp. 637-646 ◽  
Author(s):  
Susan Moir ◽  
Angela Malaspina ◽  
Yuexia Li ◽  
Tae-Wook Chun ◽  
Tomeka Lowe ◽  
...  
Keyword(s):  
T Cells ◽  
B Cells ◽  
Peripheral Blood ◽  
Mononuclear Cells ◽  
Lymphoid Tissues ◽  
Activated T Cells ◽  
Peripheral Blood Mononuclear ◽  
The Impact ◽  
Hiv 1 ◽  
Hiv Negative

The impact of HIV-associated immunopathogenesis on B cells has been largely associated with indirect consequences of viral replication. This study demonstrates that HIV interacts directly with B cells in both lymphoid tissues and peripheral blood. B cells isolated from lymph node and peripheral blood mononuclear cells (PBMCs) of 4 and 23 chronically infected patients, respectively, demonstrated similar capacities to pass virus to activated HIV-negative PBMCs when compared with CD4+ cells from the same patients. However, in contrast to T cells, virus associated with B cells was surface bound, as shown by its sensitivity to pronase and the staining pattern revealed by in situ amplification of HIV-1 RNA. Cell sorting and ligand displacing approaches established that CD21 was the HIV-binding receptor on B cells, and that this association was mediated through complement-opsonized virus. These B cells were also found to express significantly lower levels of CD21 compared with HIV-negative individuals, suggesting a direct perturbing effect of HIV on B cells. These findings suggest that B cells, although they themselves are not readily infected by HIV, are similar to follicular dendritic cells in their capacity to serve as extracellular reservoirs for HIV-1. Furthermore, B cells possess the added capability of circulating in peripheral blood and migrating through tissues where they can potentially interact with and pass virus to T cells.

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