scholarly journals Long-Term Spontaneous Control of HIV-1 Is Related to Low Frequency of Infected Cells and Inefficient Viral Reactivation

2016 ◽  
Vol 90 (13) ◽  
pp. 6148-6158 ◽  
Author(s):  
Nicolas Noel ◽  
Ruth Peña ◽  
Annie David ◽  
Veronique Avettand-Fenoel ◽  
Itziar Erkizia ◽  
...  

ABSTRACTHIV establishes reservoirs of infected cells that persist despite effective antiretroviral therapy (ART). In most patients, the virus begins to replicate soon after treatment interruption. However, a low frequency of infected cells at the time of treatment interruption has been associated with delayed viral rebound. Likewise, individuals who control the infection spontaneously, so-called HIV-1 controllers (HICs), carry particularly low levels of infected cells. It is unclear, however, whether and how this small number of infected cells contributes to durable viral control. Here we compared 38 HICs with 12 patients on effective combined antiretroviral therapy (cART) and found that the low frequency of infected cells in the former subjects was associated both with less efficient viral reactivation in resting CD4+T cells and with less efficient virion productionex vivo. We also found that a potent HIV-specific CD8+T cell response was present only in those HICs whose CD4+T cells produced virusex vivo. Long-term spontaneous control of HIV infection in HICs thus appears to be sustained on the basis of the inefficient reactivation of viruses from a limited number of infected cells and the capacity of HICs to activate a potent HIV-specific CD8+T cell response to counteract efficient viral reactivation events.IMPORTANCEThere is a strong scientific interest in developing strategies to eradicate the HIV-1 reservoir. Very rare HIV-1-infected patients are able to spontaneously control viremia for long periods of time (HIV-1 controllers [HICs]) and are put forward as a model of HIV-1 remission. Here, we show that the low viral reservoirs found in HICs are a critical part of the mechanisms underlying viral control and result in a lower probability of HIV-1 reactivation events, resulting in limited HIV-1 release and spread. We found that those HICs in whom viral reactivation and spread from CD4+T cellsin vitrowere the most difficult were those with diminished CD8+T cell responses. These results suggest that, in some settings, low HIV-1 reservoirs decisively contribute to at least the temporary control of infection without antiretroviral therapy. We believe that this work provides information of relevance in the context of the search for HIV-1 remission.

Blood ◽  
2000 ◽  
Vol 96 (4) ◽  
pp. 1327-1333 ◽  
Author(s):  
Andreas Gruber ◽  
June Kan-Mitchell ◽  
Kelli L. Kuhen ◽  
Tetsu Mukai ◽  
Flossie Wong-Staal

Abstract Dendritic cells (DCs) genetically modified to continually express and present antigens may be potent physiologic adjuvants for induction of prophylactic or therapeutic immunity. We have previously shown that an env and nef deleted HIV-1 vector (HIV-1ΔEN) pseudotyped with VSV-G transduced monocyte-derived macrophages as well as CD34+ precursors of DCs. Here we extended these findings with HIV-1ΔEN to highly differentiated human DCs derived in culture from circulating monocytes (DCs). In addition, a new vector derived from HIV-1ΔEN but further deleted in its remaining accessory genes vif, vpr, and vpu(HIV-1ΔEN V3) was also tested. Both vectors efficiently transduced DCs. Transduction of DCs did not significantly alter their viability or their immunophenotype when compared with untransduced DCs. Furthermore, the phagocytic potential of immature DCs, as well as their ability to differentiate into mature DCs capable of stimulating T-cell proliferation, was not affected. Finally, DCs transduced by the HIV-1ΔEN vector were able to elicit a primary antiviral cytotoxic T-cell response in autologous CD8 T cells. These results suggest that HIV-1–based vectors expressing viral antigens may be useful for in vivo active immunization as well as ex vivo priming of cytotoxic T cells for adoptive T-cell therapy.


2015 ◽  
Vol 89 (22) ◽  
pp. 11284-11293 ◽  
Author(s):  
Hong Sun ◽  
Dhohyung Kim ◽  
Xiaodong Li ◽  
Maja Kiselinova ◽  
Zhengyu Ouyang ◽  
...  

ABSTRACTThe ability to persist long term in latently infected CD4 T cells represents a characteristic feature of HIV-1 infection and the predominant barrier to efforts aiming at viral eradication and cure. Yet, increasing evidence suggests that only small subsets of CD4 T cells with specific developmental and maturational profiles are able to effectively support HIV-1 long-term persistence. Here, we analyzed how the functional polarization of CD4 T cells shapes and structures the reservoirs of HIV-1-infected cells. We found that CD4 T cells enriched for a Th1/17 polarization had elevated susceptibilities to HIV-1 infection inex vivoassays, harbored high levels of HIV-1 DNA in persons treated with antiretroviral therapy, and made a disproportionately increased contribution to the viral reservoir relative to their contribution to the CD4 T memory cell pool. Moreover, HIV-1 DNA levels in Th1/17 cells remained stable over many years of antiretroviral therapy, resulting in a progressively increasing contribution of these cells to the viral reservoir, and phylogenetic studies suggested preferential long-term persistence of identical viral sequences during prolonged antiretroviral treatment in this cell compartment. Together, these data suggest that Th1/17 CD4 T cells represent a preferred site for HIV-1 DNA long-term persistence in patients receiving antiretroviral therapy.IMPORTANCECurrent antiretroviral therapy is very effective in suppressing active HIV-1 replication but does not fully eliminate virally infected cells. The ability of HIV-1 to persist long term despite suppressive antiretroviral combination therapy represents a perplexing aspect of HIV-1 disease pathogenesis, since most HIV-1 target cells are activated, short-lived CD4 T cells. This study suggests that CD4 T helper cells with Th1/17 polarization have a preferential role as a long-term reservoir for HIV-1 infection during antiretroviral therapy, possibly because these cells may imitate some of the functional properties traditionally attributed to stem cells, such as the ability to persist for extremely long periods of time and to repopulate their own pool size through homeostatic self-renewal. These observations support the hypothesis that HIV-1 persistence is driven by small subsets of long-lasting stem cell-like CD4 T cells that may represent particularly promising targets for clinical strategies aiming at HIV-1 eradication and cure.


2015 ◽  
Vol 89 (18) ◽  
pp. 9631-9638 ◽  
Author(s):  
Victoria E. K. Walker-Sperling ◽  
Valerie J. Cohen ◽  
Patrick M. Tarwater ◽  
Joel N. Blankson

ABSTRACTThe “shock and kill” model of human immunodeficiency virus type 1 (HIV-1) eradication involves the induction of transcription of HIV-1 genes in latently infected CD4+T cells, followed by the elimination of these infected CD4+T cells by CD8+T cells or other effector cells. CD8+T cells may also be needed to control the spread of new infection if residual infected cells are present at the time combination antiretroviral therapy (cART) is discontinued. In order to determine the time frame needed for CD8+T cells to effectively prevent the spread of HIV-1 infection, we examined the kinetics of HIV transcription and virus release in latently infected cells reactivatedex vivo. Isolated resting, primary CD4+T cells from HIV-positive (HIV+) subjects on suppressive regimens were found to upregulate cell-associated HIV-1 mRNA within 1 h of stimulation and produce extracellular virus as early as 6 h poststimulation. In spite of the rapid kinetics of virus production, we show that CD8+T cells from 2 out of 4 viremic controllers were capable of effectively eliminating reactivated autologous CD4+cells that upregulate cell-associated HIV-1 mRNA. The results have implications for devising strategies to prevent rebound viremia due to reactivation of rare latently infected cells that persist after potentially curative therapy.IMPORTANCEA prominent HIV-1 cure strategy termed “shock and kill” involves the induction of HIV-1 transcription in latently infected CD4+T cells with the goal of elimination of these cells by either the cytotoxic T lymphocyte response or other immune cell subsets. However, the cytotoxic T cell response may also be required after curative treatment if residual latently infected cells remain. The kinetics of HIV-1 reactivation indicate rapid upregulation of cell-associated HIV-1 mRNA and a 5-h window between transcription and virus release. Thus, HIV-specific CD8+T cell responses likely have a very short time frame to eliminate residual latently infected CD4+T cells that become reactivated after discontinuation of antiretroviral therapy following potentially curative treatment strategies.


Blood ◽  
2000 ◽  
Vol 96 (4) ◽  
pp. 1327-1333 ◽  
Author(s):  
Andreas Gruber ◽  
June Kan-Mitchell ◽  
Kelli L. Kuhen ◽  
Tetsu Mukai ◽  
Flossie Wong-Staal

Dendritic cells (DCs) genetically modified to continually express and present antigens may be potent physiologic adjuvants for induction of prophylactic or therapeutic immunity. We have previously shown that an env and nef deleted HIV-1 vector (HIV-1ΔEN) pseudotyped with VSV-G transduced monocyte-derived macrophages as well as CD34+ precursors of DCs. Here we extended these findings with HIV-1ΔEN to highly differentiated human DCs derived in culture from circulating monocytes (DCs). In addition, a new vector derived from HIV-1ΔEN but further deleted in its remaining accessory genes vif, vpr, and vpu(HIV-1ΔEN V3) was also tested. Both vectors efficiently transduced DCs. Transduction of DCs did not significantly alter their viability or their immunophenotype when compared with untransduced DCs. Furthermore, the phagocytic potential of immature DCs, as well as their ability to differentiate into mature DCs capable of stimulating T-cell proliferation, was not affected. Finally, DCs transduced by the HIV-1ΔEN vector were able to elicit a primary antiviral cytotoxic T-cell response in autologous CD8 T cells. These results suggest that HIV-1–based vectors expressing viral antigens may be useful for in vivo active immunization as well as ex vivo priming of cytotoxic T cells for adoptive T-cell therapy.


2019 ◽  
Vol 11 (520) ◽  
pp. eaax7350 ◽  
Author(s):  
Pilar Garcia-Broncano ◽  
Shivaali Maddali ◽  
Kevin B. Einkauf ◽  
Chenyang Jiang ◽  
Ce Gao ◽  
...  

Neonatal HIV-1 infection is associated with rapidly progressive and frequently fatal immune deficiency if left untreated. Immediate institution of antiretroviral therapy (ART), ideally within hours after birth, may restrict irreversible damage to the developing neonatal immune system and possibly provide opportunities for facilitating drug-free viral control during subsequent treatment interruptions. However, the virological and immunological effects of ART initiation within hours after delivery have not been systematically investigated. We examined a unique cohort of neonates with HIV-1 infection from Botswana who started ART shortly after birth and were followed longitudinally for about 2 years in comparison to control infants started on treatment during the first year after birth. We demonstrate multiple clear benefits of rapid antiretroviral initiation, including an extremely small reservoir of intact proviral sequences, a reduction in abnormal T cell immune activation, a more polyfunctional HIV-1–specific T cell response, and an innate immune profile that displays distinct features of improved antiviral activity and is associated with intact proviral reservoir size. Together, these data offer rare insight into the evolutionary dynamics of viral reservoir establishment in neonates and provide strong empirical evidence supporting the immediate initiation of ART for neonates with HIV-1 infection.


2010 ◽  
Vol 84 (20) ◽  
pp. 10543-10557 ◽  
Author(s):  
Rebecca P. Payne ◽  
Henrik Kløverpris ◽  
Jonah B. Sacha ◽  
Zabrina Brumme ◽  
Chanson Brumme ◽  
...  

ABSTRACT The association between HLA-B*2705 and the immune control of human immunodeficiency virus type 1 (HIV-1) has previously been linked to the targeting of the HLA-B*2705-restricted Gag epitope KRWIILGLNK (KK10) by CD8+ T cells. In order to better define the mechanisms of the HLA-B*2705 immune control of HIV, we first characterized the CD8+ T-cell responses of nine highly active antiretroviral therapy (HAART)-naïve B*2705-positive subjects. Unexpectedly, we observed a strong response to an HLA-B*2705-restricted Pol epitope, KRKGGIGGY (KY9), in 8/9 subjects. The magnitude of the KY9 response was only marginally lower than that of the KK10-specific response (median, 695 versus 867 spot-forming cells [SFC]/million peripheral blood mononuclear cells [PBMCs]; not significant [NS]), and viral escape mutants were observed in both KY9 and KK10, resulting from selection pressure driven by the respective CD8+ T-cell response. By comparing inhibitions of viral replication by CD8+ T cells specific for the Gag KK10, Pol KY9, and Vpr VL9 HLA-B*2705-restricted epitopes, we observed a consistent hierarchy of antiviral efficacy (Gag KK10 > Pol KY9 > Vpr VL9). This hierarchy was associated with early recognition of HIV-1-infected cells, within 6 h of infection, by KK10- and KY9-specific CD8+ T cells but not until 18 h postinfection by VL9-specific CD8+ T cells. There was no association between antiviral efficacy and proliferative capacity, cytotoxicity, polyfunctionality, or T-cell receptor (TCR) avidity. These data are consistent with previous studies indicating an important role for the B*2705-Gag KK10 response in the control of HIV but also suggest a previously unrecognized role played by the subdominant Pol-specific KY9 response in HLA-B*2705-mediated control of HIV and that the recognition of HIV-infected cells by CD8+ T cells early in the viral life cycle may be important for viral containment in HIV-infected individuals.


2016 ◽  
Vol 90 (21) ◽  
pp. 9712-9724 ◽  
Author(s):  
Bingfeng Liu ◽  
Fan Zou ◽  
Lijuan Lu ◽  
Cancan Chen ◽  
Dalian He ◽  
...  

ABSTRACT Despite the advent of combined antiretroviral therapy (cART), the persistence of viral reservoirs remains a major barrier to curing human immunodeficiency virus type 1 (HIV-1) infection. Recently, the shock and kill strategy, by which such reservoirs are eradicated following reactivation of latent HIV-1 by latency-reversing agents (LRAs), has been extensively practiced. It is important to reestablish virus-specific and reliable immune surveillance to eradicate the reactivated virus-harboring cells. In this report, we attempted to reach this goal by using newly developed chimeric antigen receptor (CAR)-T cell technology. To generate anti-HIV-1 CAR-T cells, we connected the single-chain variable fragment of the broadly neutralizing HIV-1-specific antibody VRC01 to a third-generation CAR moiety as the extracellular and intracellular domains and subsequently transduced this into primary CD8 + T lymphocytes. We demonstrated that the resulting VC-CAR-T cells induced T cell-mediated cytolysis of cells expressing HIV-1 Env proteins and significantly inhibited HIV-1 rebound after removal of antiviral inhibitors in a viral infectivity model in cell culture that mimics the termination of the cART in the clinic. Importantly, the VC-CAR-T cells also effectively induced the cytolysis of LRA-reactivated HIV-1-infected CD4 + T lymphocytes isolated from infected individuals receiving suppressive cART. Our data demonstrate that the special features of genetically engineered CAR-T cells make them a particularly suitable candidate for therapeutic application in efforts to reach a functional HIV cure. IMPORTANCE The presence of latently infected cells remains a key obstacle to the development of a functional HIV-1 cure. Reactivation of dormant viruses is possible with latency-reversing agents, but the effectiveness of these compounds and the subsequent immune response require optimization if the eradication of HIV-1-infected cells is to be achieved. Here, we describe the use of a chimeric antigen receptor, comprised of T cell activation domains and a broadly neutralizing antibody, VRC01, targeting HIV-1 to treat the infected cells. T cells expressing this construct exerted specific cytotoxic activity against wild-type HIV-1-infected cells, resulting in a dramatic reduction in viral rebound in vitro , and showed persistent effectiveness against reactivated latently infected T lymphocytes from HIV-1 patients receiving combined antiretroviral therapy. The methods used in this study constitute an improvement over existing CD4-based CAR-T technology and offer a promising approach to HIV-1 immunotherapy.


2016 ◽  
Vol 90 (15) ◽  
pp. 6818-6831 ◽  
Author(s):  
Catherine K. Koofhethile ◽  
Zaza M. Ndhlovu ◽  
Christina Thobakgale-Tshabalala ◽  
Julia G. Prado ◽  
Nasreen Ismail ◽  
...  

ABSTRACTThe mechanisms of viral control and loss of viral control in chronically infected individuals with or without protective HLA class I alleles are not fully understood. We therefore characterized longitudinally the immunological and virological features that may explain divergence in disease outcome in 70 HIV-1 C-clade-infected antiretroviral therapy (ART)-naive South African adults, 35 of whom possessed protective HLA class I alleles. We demonstrate that, over 5 years of longitudinal study, 35% of individuals with protective HLA class I alleles lost viral control compared to none of the individuals without protective HLA class I alleles (P= 0.06). Sustained HIV-1 control in patients with protective HLA class I alleles was characteristically related to the breadth of HIV-1 CD8+T cell responses against Gag and enhanced ability of CD8+T cells to suppress viral replicationex vivo. In some cases, loss of virological control was associated with reduction in the total breadth of CD8+T cell responses in the absence of differences in HIV-1-specific CD8+T cell polyfunctionality or proliferation. In contrast, viremic controllers without protective HLA class I alleles possessed reduced breadth of HIV-1-specific CD8+T cell responses characterized by reduced ability to suppress viral replicationex vivo. These data suggest that the control of HIV-1 in individuals with protective HLA class I alleles may be driven by broad CD8+T cell responses with potent viral inhibitory capacity while control among individuals without protective HLA class I alleles may be more durable and mediated by CD8+T cell-independent mechanisms.IMPORTANCEHost mechanisms of natural HIV-1 control are not fully understood. In a longitudinal study of antiretroviral therapy (ART)-naive individuals, we show that those with protective HLA class I alleles subsequently experienced virologic failure compared to those without protective alleles. Among individuals with protective HLA class I alleles, viremic control was associated with broad CD8+T cells that targeted the Gag protein, and CD8+T cells from these individuals exhibited superior virus inhibition capacity. In individuals without protective HLA class I alleles, HIV-1-specific CD8+T cell responses were narrow and poorly inhibited virus replication. These results suggest that broad, highly functional cytotoxic T cells (cytotoxic T lymphocytes [CTLs]) against the HIV-1 Gag protein are associated with control among those with protective HLA class I alleles and that loss of these responses eventually leads to viremia. A subset of individuals appears to have alternative, non-CTL mechanisms of viral control. These controllers may hold the key to an effective HIV vaccine.


Blood ◽  
2011 ◽  
Vol 118 (4) ◽  
pp. 955-964 ◽  
Author(s):  
Asier Sáez-Cirión ◽  
Chiraz Hamimi ◽  
Anna Bergamaschi ◽  
Annie David ◽  
Pierre Versmisse ◽  
...  

Abstract How HIV controllers (HICs) maintain undetectable viremia without therapy is unknown. The strong CD8+ T-cell HIV suppressive capacity found in many, but not all, HICs may contribute to long-lasting viral control. However, other earlier defense mechanisms may be involved. Here, we examined intrinsic HIC cell resistance to HIV-1 infection. After in vitro challenge, monocyte-derived macrophages and anti–CD3-activated CD4+ T cells from HICs showed low HIV-1 susceptibility. CD4 T-cell resistance was independent of HIV-1 coreceptors and affected also SIVmac infection. CD4+ T cells from HICs expressed ex vivo higher levels of p21Waf1/Cip1, which has been involved in the control of HIV-1 replication, than cells from control subjects. However, HIV restriction in anti–CD3-activated CD4+ T cells and macrophages was not associated with p21 expression. Restriction inhibited accumulation of reverse transcripts, leading to reduction of HIV-1 integrated proviruses. The block could be overcome by high viral inocula, suggesting the action of a saturable mechanism. Importantly, cell-associated HIV-1 DNA load was extremely low in HICs and correlated with CD4+ T-cell permissiveness to infection. These results point to a contribution of intrinsic cell resistance to the control of infection and the containment of viral reservoir in HICs.


mBio ◽  
2016 ◽  
Vol 7 (3) ◽  
Author(s):  
Kellie N. Smith ◽  
Robbie B. Mailliard ◽  
Paolo A. Piazza ◽  
Will Fischer ◽  
Bette T. Korber ◽  
...  

ABSTRACTCuring HIV-1 infection will require elimination of persistent cellular reservoirs that harbor latent virus in the face of combination antiretroviral therapy (cART). Proposed immunotherapeutic strategies to cure HIV-1 infection include enhancing lysis of these infected cells by cytotoxic T lymphocytes (CTL). A major challenge in this strategy is overcoming viral immune escape variants that have evaded host immune control. Here we report that naive CD8+T cells from chronic HIV-1-infected participants on long-term cART can be primed by dendritic cells (DC). These DC must be mature, produce high levels of interleukin 12p70 (IL-12p70), be responsive to CD40 ligand (CD40L), and be loaded with inactivated, autologous HIV-1. These DC-primed CD8+T cell responders produced high levels of gamma interferon (IFN-γ) in response to a broad range of both conserved and variable regions of Gag and effectively killed CD4+T cell targets that were either infected with the autologous latent reservoir-associated virus or loaded with autologous Gag peptides. In contrast, HIV-1-specific memory CD8+T cells stimulated with autologous HIV-1-loaded DC produced IFN-γ in response to a narrow range of conserved and variable Gag peptides compared to the primed T cells and most notably, displayed significantly lower cytolytic function. Our findings highlight the need to selectively induce new HIV-1-specific CTL from naive precursors while avoiding activation of existing, dysfunctional memory T cells in potential curative immunotherapeutic strategies for HIV-1 infection.IMPORTANCECurrent immunotherapeutic approaches aim to enhance antiviral immunity against the HIV-1 reservoir; however, it has yet to be shown whether T cells from persons on cART can recognize and eliminate virus-infected cells. We show that in persons on cART a personalized medicine approach using their dendritic cells to stimulate their naive T cells induces potent effector CTLin vitrothat recognize and eradicate HIV-1-infected CD4+T cells. Additionally, we show that the same stimulation of existing memory T cells results in cytokine secretion but limited effector function. Our study demonstrates that the naive T cell repertoire can recognize persistent HIV-1 during cART and supports immunotherapy strategies for an HIV-1 cure that targets naive T cells, rather than existing, dysfunctional, memory T cells.


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