scholarly journals Novel CD4-Based Bispecific Chimeric Antigen Receptor Designed for Enhanced Anti-HIV Potency and Absence of HIV Entry Receptor Activity

2015 ◽  
Vol 89 (13) ◽  
pp. 6685-6694 ◽  
Author(s):  
Li Liu ◽  
Bhavik Patel ◽  
Mustafa H. Ghanem ◽  
Virgilio Bundoc ◽  
Zhili Zheng ◽  
...  
Keyword(s):  
T Cells ◽  
Antiretroviral Therapy ◽  
Hiv Infection ◽  
Chimeric Antigen Receptor ◽  
Cd8 T Cells ◽  
Genetically Engineered ◽  
Functional Cure ◽  
Gp120 Subunit ◽  
Infected Cells ◽  
Hiv 1

ABSTRACTAdoptive transfer of CD8 T cells genetically engineered to express “chimeric antigen receptors” (CARs) represents a potential approach toward an HIV infection “functional cure” whereby durable virologic suppression is sustained after discontinuation of antiretroviral therapy. We describe a novel bispecific CAR in which a CD4 segment is linked to a single-chain variable fragment of the 17b human monoclonal antibody recognizing a highly conserved CD4-induced epitope on gp120 involved in coreceptor binding. We compared a standard CD4 CAR with CD4-17b CARs where the polypeptide linker between the CD4 and 17b moieties is sufficiently long (CD4-35-17b CAR) versus too short (CD4-10-17b) to permit simultaneous binding of the two moieties to a single gp120 subunit. When transduced into a peripheral blood mononuclear cell (PBMC) or T cells thereof, all three CD4-based CARs displayed specific functional activities against HIV-1 Env-expressing target cells, including stimulation of gamma interferon (IFN-γ) release, specific target cell killing, and suppression of HIV-1 pseudovirus production. In assays of spreading infection of PBMCs with genetically diverse HIV-1 primary isolates, the CD4-10-17b CAR displayed enhanced potency compared to the CD4 CAR whereas the CD4-35-17b CAR displayed diminished potency. Importantly, both CD4-17b CARs were devoid of a major undesired activity observed with the CD4 CAR, namely, rendering the transduced CD8+T cells susceptible to HIV-1 infection. Likely mechanisms for the superior potency of the CD4-10-17b CAR over the CD4-35-17b CAR include the greater potential of the former to engage in the serial antigen binding required for efficient T cell activation and the ability of two CD4-10-17b molecules to simultaneously bind a single gp120 subunit.IMPORTANCEHIV research has been energized by prospects for a cure for HIV infection or, at least, for a “functional cure” whereby antiretroviral therapy can be discontinued without virus rebound. This report describes a novel CD4-based “chimeric antigen receptor” (CAR) which, when genetically engineered into T cells, gives them the capability to selectively respond to and kill HIV-infected cells. This CAR displays enhanced features compared to previously described CD4-based CARs, namely, increased potency and avoidance of the undesired rendering of the genetically modified CD8 T cells susceptible to HIV infection. When adoptively transferred back to the individual, the genetically modified T cells will hopefully provide durable killing of infected cells and sustained virus suppression without continued antiretroviral therapy, i.e., a functional cure.

scholarly journals Chimeric Antigen Receptor T Cells Guided by the Single-Chain Fv of a Broadly Neutralizing Antibody Specifically and Effectively Eradicate Virus Reactivated from Latency in CD4 + T Lymphocytes Isolated from HIV-1-Infected Individuals Receiving Suppressive Combined Antiretroviral Therapy

2016 ◽  
Vol 90 (21) ◽  
pp. 9712-9724 ◽  
Author(s):  
Bingfeng Liu ◽  
Fan Zou ◽  
Lijuan Lu ◽  
Cancan Chen ◽  
Dalian He ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
Antiretroviral Therapy ◽  
T Lymphocytes ◽  
Chimeric Antigen Receptor ◽  
Car T Cells ◽  
Combined Antiretroviral Therapy ◽  
Car T ◽  
Infected Cells ◽  
Hiv 1

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.

scholarly journals Induction of Autophagy to Achieve a Human Immunodeficiency Virus Type 1 Cure

Cells ◽  
2021 ◽  
Vol 10 (7) ◽  
pp. 1798
Author(s):  
Grant R. Campbell ◽  
Stephen A. Spector
Keyword(s):  
Human Immunodeficiency Virus ◽  
Antiretroviral Therapy ◽  
Human Immunodeficiency Virus Type ◽  
Virus Type ◽  
Functional Cure ◽  
Immunodeficiency Virus ◽  
Latently Infected ◽  
Infected Cells ◽  
Hiv 1

Effective antiretroviral therapy has led to significant human immunodeficiency virus type 1 (HIV-1) suppression and improvement in immune function. However, the persistence of integrated proviral DNA in latently infected reservoir cells, which drive viral rebound post-interruption of antiretroviral therapy, remains the major roadblock to a cure. Therefore, the targeted elimination or permanent silencing of this latently infected reservoir is a major focus of HIV-1 research. The most studied approach in the development of a cure is the activation of HIV-1 expression to expose latently infected cells for immune clearance while inducing HIV-1 cytotoxicity—the “kick and kill” approach. However, the complex and highly heterogeneous nature of the latent reservoir, combined with the failure of clinical trials to reduce the reservoir size casts doubt on the feasibility of this approach. This concern that total elimination of HIV-1 from the body may not be possible has led to increased emphasis on a “functional cure” where the virus remains but is unable to reactivate which presents the challenge of permanently silencing transcription of HIV-1 for prolonged drug-free remission—a “block and lock” approach. In this review, we discuss the interaction of HIV-1 and autophagy, and the exploitation of autophagy to kill selectively HIV-1 latently infected cells as part of a cure strategy. The cure strategy proposed has the advantage of significantly decreasing the size of the HIV-1 reservoir that can contribute to a functional cure and when optimised has the potential to eradicate completely HIV-1.

Increases in T Cell Telomere Length in HIV Infection after Antiretroviral Combination Therapy for HIV-1 Infection Implicate Distinct Population Dynamics in CD4+ and CD8+ T Cells

1999 ◽  
Vol 92 (1) ◽  
pp. 14-24 ◽  
Author(s):  
Sumesh Kaushal ◽  
Alan L. Landay ◽  
Michael M. Lederman ◽  
Elizabeth Connick ◽  
John Spritzler ◽  
...  
Keyword(s):  
T Cells ◽  
Population Dynamics ◽  
T Cell ◽  
Combination Therapy ◽  
Hiv Infection ◽  
Telomere Length ◽  
Cd8 T Cells ◽  
Distinct Population ◽  
Hiv 1

scholarly journals Infection of CD8+CD45RO+ Memory T-Cells by HIV-1 and Their Proliferative Response

2008 ◽  
Vol 2 (1) ◽  
pp. 43-57 ◽  
Author(s):  
Naveed Gulzar ◽  
Sowyma Balasubramanian ◽  
Greg Harris ◽  
Jaime Sanchez-Dardon ◽  
Karen F.T. Copeland
Keyword(s):  
T Cells ◽  
T Cell ◽  
Cd8 T Cells ◽  
Proliferative Response ◽  
Cell Infection ◽  
Cellular Target ◽  
Potential Reservoir ◽  
Infected Cells ◽  
Hiv 1

CD8+ T-cells are involved in controlling HIV-1 infection by eliminating infected cells and secreting soluble factors that inhibit viral replication. To investigate the mechanism and significance of infection of CD8+ T-cells by HIV-1in vitro, we examined the susceptibility of these cells and their subsets to infection. CD8+ T-cells supported greater levels of replication with T-cell tropic strains of HIV-1, though viral production was lower than that observed in CD4+ T-cells. CD8+ T-cell infection was found to be productive through ELISA, RT-PCR and flow cytometric analyses. In addition, the CD8+CD45RO+ memory T-cell population supported higher levels of HIV-1 replication than CD8+CD45RA+ naïve T-cells. However, infection of CD8+CD45RO+ T-cells did not affect their proliferative response to the majority of mitogens tested. We conclude, with numerous lines of evidence detecting and measuring infection of CD8+ T-cells and their subsets, that this cellular target and potential reservoir may be central to HIV-1 pathogenesis.

scholarly journals Specific Inhibition of HIV Infection by the Action of Spironolactone in T Cells

2016 ◽  
Vol 90 (23) ◽  
pp. 10972-10980 ◽  
Author(s):  
Benoît Lacombe ◽  
Marina Morel ◽  
Florence Margottin-Goguet ◽  
Bertha Cecilia Ramirez
Keyword(s):  
T Cells ◽  
T Cell ◽  
Antiretroviral Therapy ◽  
Hiv Infection ◽  
Tat Protein ◽  
Aldosterone Antagonist ◽  
Hiv Transcription ◽  
Hiv Tat ◽  
Cellular Cofactor ◽  
Hiv 1

ABSTRACTTat protein, the HIV transactivator, regulates transcription of the HIV genome by the host transcription machinery. Efficient inhibitors of HIV transcription that target Tat or the cellular cofactor NF-κB are well known. However, inhibition of HIV Tat-dependent transcription by targeting the general transcription and DNA repair factor II human (TFIIH) has not been reported. Here, we show that spironolactone (SP), an aldosterone antagonist approved for clinical use, inhibits HIV-1 and HIV-2 infection of permissive T cells by blocking viral Tat-dependent transcription from the long terminal repeat (LTR). We found that treatment of Jurkat and primary CD4+T cells with SP induces degradation of the XPB cellular helicase, a component of the TFIIH complex, without affecting cellular mRNA levels, T cell viability, or T cell proliferation. We further demonstrate that the effect of SP on HIV infection is independent of its aldosterone antagonist function, since the structural analogue, eplerenone, does not induce XPB degradation and does not inhibit HIV infection. Rescue experiments showed that the SP-induced block of HIV infection relies, at least partially, on XPB degradation. In addition, we demonstrate that SP specifically inhibits Tat-dependent transcription, since basal transcription from the LTR is not affected. Our results demonstrate that SP is a specific inhibitor of HIV Tat-dependent transcription in T cells, which additionally suggests that XPB is a cofactor required for HIV infection. Targeting a cellular cofactor of HIV transcription constitutes an alternative strategy to inhibit HIV infection, together with the existing antiretroviral therapy.IMPORTANCETranscription from the HIV promoter is regulated by the combined activities of the host transcription machinery and the viral transactivator Tat protein. Here, we report that the drug spironolactone—an antagonist of aldosterone—blocks viral Tat-dependent transcription, thereby inhibiting both HIV-1 and HIV-2 infection of permissive T cells. This inhibition relies on the degradation of the cellular helicase XPB, a component of the TFIIH transcription factor complex. Consequently, XPB appears to be a novel HIV cofactor. Our discovery of the HIV-inhibitory activity of spironolactone opens the way for the development of novel anti-HIV strategies targeting a cellular cofactor without the limitations of antiretroviral therapy of drug resistance and high cost.

scholarly journals Plasmatic Levels of IL-18, IP-10, and Activated CD8+ T Cells Are Potential Biomarkers to Identify HIV-1 Elite Controllers With a True Functional Cure Profile

2018 ◽  
Vol 9 ◽  
Author(s):  
Fernanda H. Côrtes ◽  
Hury H. S. de Paula ◽  
Gonzalo Bello ◽  
Marcelo Ribeiro-Alves ◽  
Suwellen S. D. de Azevedo ◽  
...  
Keyword(s):  
T Cells ◽  
Cd8 T Cells ◽  
Elite Controllers ◽  
Functional Cure ◽  
Hiv 1 ◽  
Potential Biomarkers

scholarly journals Th1/17 Polarization of CD4 T Cells Supports HIV-1 Persistence during Antiretroviral Therapy

2015 ◽  
Vol 89 (22) ◽  
pp. 11284-11293 ◽  
Author(s):  
Hong Sun ◽  
Dhohyung Kim ◽  
Xiaodong Li ◽  
Maja Kiselinova ◽  
Zhengyu Ouyang ◽  
...  
Keyword(s):  
T Cells ◽  
Antiretroviral Therapy ◽  
Cd4 T Cells ◽  
Ex Vivo ◽  
Memory Cell ◽  
Viral Reservoir ◽  
Target Cells ◽  
Infected Cells ◽  
Hiv 1

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.

scholarly journals Reactivation Kinetics of HIV-1 and Susceptibility of Reactivated Latently Infected CD4+T Cells to HIV-1-Specific CD8+T Cells

2015 ◽  
Vol 89 (18) ◽  
pp. 9631-9638 ◽  
Author(s):  
Victoria E. K. Walker-Sperling ◽  
Valerie J. Cohen ◽  
Patrick M. Tarwater ◽  
Joel N. Blankson
Keyword(s):  
T Cells ◽  
T Cell ◽  
Antiretroviral Therapy ◽  
Time Frame ◽  
Virus Release ◽  
Latently Infected ◽  
Shock And Kill ◽  
Infected Cells ◽  
Kinetics Of ◽  
Hiv 1

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.

Dressed to kill? A review of why antiviral CD8 T lymphocytes fail to prevent progressive immunodeficiency in HIV-1 infection

Blood ◽  
2001 ◽  
Vol 98 (6) ◽  
pp. 1667-1677 ◽  
Author(s):  
Judy Lieberman ◽  
Premlata Shankar ◽  
N. Manjunath ◽  
Jan Andersson
Keyword(s):  
T Cells ◽  
T Cell ◽  
T Lymphocytes ◽  
Cd8 T Cells ◽  
Interleukin 2 ◽  
Interferon Γ ◽  
Short Term Exposure ◽  
Infected Cells ◽  
Hiv 1

Abstract CD8 T cells play an important role in protection and control of HIV-1 by direct cytolysis of infected cells and by suppression of viral replication by secreted factors. However, although HIV-1–infected individuals have a high frequency of HIV-1–specific CD8 T cells, viral reservoirs persist and progressive immunodeficiency generally ensues in the absence of continuous potent antiviral drugs. Freshly isolated HIV-specific CD8 T cells are often unable to lyse HIV-1–infected cells. Maturation into competent cytotoxic T lymphocytes may be blocked during the initial encounter with antigen because of defects in antigen presentation by interdigitating dendritic cells or HIV-infected macrophages. The molecular basis for impaired function is multifactorial, due to incomplete T-cell signaling and activation (in part related to CD3ζ and CD28 down-modulation), reduced perforin expression, and inefficient trafficking of HIV-specific CD8 T cells to lymphoid sites of infection. CD8 T-cell dysfunction can partially be corrected in vitro with short-term exposure to interleukin 2, suggesting that impaired HIV-specific CD4 T helper function may play a significant causal or exacerbating role. Functional defects are qualitatively different and more severe with advanced disease, when interferon γ production also becomes compromised.

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