RESUMO
Human immunodeficiency virus type 1 (HIV-1) infection persists despite years of antiretroviral therapy (ART). To remove the stigma and burden of chronic infection, approaches to eradicate or cure HIV infection are desired. Attempts to augment ART with therapies that reverse viral latency, paired with immunotherapies to clear infection, have advanced into the clinic, but the field is still in its infancy. We review foundational studies and highlight new insights in HIV cure research. Together with advances in ART delivery and HIV prevention strategies, future therapies that clear HIV infection may relieve society of the affliction of the HIV pandemic.
Assuntos
Fármacos Anti-HIV/uso terapêutico , Doença Crônica/terapia , Infecções por HIV/terapia , HIV-1/efeitos dos fármacos , Imunoterapia/métodos , Latência Viral/efeitos dos fármacos , Animais , Haplorrinos , HumanosRESUMO
All coronaviruses known to have recently emerged as human pathogens probably originated in bats1. Here we use a single experimental platform based on immunodeficient mice implanted with human lung tissue (hereafter, human lung-only mice (LoM)) to demonstrate the efficient in vivo replication of severe acute respiratory syndrome coronavirus (SARS-CoV), Middle East respiratory syndrome coronavirus (MERS-CoV) and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), as well as two endogenous SARS-like bat coronaviruses that show potential for emergence as human pathogens. Virus replication in this model occurs in bona fide human lung tissue and does not require any type of adaptation of the virus or the host. Our results indicate that bats contain endogenous coronaviruses that are capable of direct transmission to humans. Our detailed analysis of in vivo infection with SARS-CoV-2 in human lung tissue from LoM showed a predominant infection of human lung epithelial cells, including type-2 pneumocytes that are present in alveoli and ciliated airway cells. Acute infection with SARS-CoV-2 was highly cytopathic and induced a robust and sustained type-I interferon and inflammatory cytokine and chemokine response. Finally, we evaluated a therapeutic and pre-exposure prophylaxis strategy for SARS-CoV-2 infection. Our results show that therapeutic and prophylactic administration of EIDD-2801-an oral broad-spectrum antiviral agent that is currently in phase II/III clinical trials-markedly inhibited SARS-CoV-2 replication in vivo, and thus has considerable potential for the prevention and treatment of COVID-19.
Assuntos
Tratamento Farmacológico da COVID-19 , COVID-19/prevenção & controle , Citidina/análogos & derivados , Hidroxilaminas/administração & dosagem , Hidroxilaminas/uso terapêutico , Administração Oral , Células Epiteliais Alveolares/imunologia , Células Epiteliais Alveolares/patologia , Células Epiteliais Alveolares/virologia , Animais , COVID-19/imunologia , Quimioprevenção , Quirópteros/virologia , Ensaios Clínicos Fase II como Assunto , Ensaios Clínicos Fase III como Assunto , Citidina/administração & dosagem , Citidina/uso terapêutico , Citocinas/imunologia , Células Epiteliais/virologia , Feminino , Xenoenxertos , Humanos , Imunidade Inata , Interferon Tipo I/imunologia , Pulmão/imunologia , Pulmão/patologia , Pulmão/virologia , Transplante de Pulmão , Masculino , Camundongos , Profilaxia Pós-Exposição , Profilaxia Pré-Exposição , SARS-CoV-2/imunologia , SARS-CoV-2/patogenicidade , Replicação ViralRESUMO
An Amendment to this paper has been published and can be accessed via a link at the top of the paper.
RESUMO
Human immunodeficiency virus (HIV) persists indefinitely in individuals with HIV who receive antiretroviral therapy (ART) owing to a reservoir of latently infected cells that contain replication-competent virus1-4. Here, to better understand the mechanisms responsible for latency persistence and reversal, we used the interleukin-15 superagonist N-803 in conjunction with the depletion of CD8+ lymphocytes in ART-treated macaques infected with simian immunodeficiency virus (SIV). Although N-803 alone did not reactivate virus production, its administration after the depletion of CD8+ lymphocytes in conjunction with ART treatment induced robust and persistent reactivation of the virus in vivo. We found viraemia of more than 60 copies per ml in all macaques (n = 14; 100%) and in 41 out of a total of 56 samples (73.2%) that were collected each week after N-803 administration. Notably, concordant results were obtained in ART-treated HIV-infected humanized mice. In addition, we observed that co-culture with CD8+ T cells blocked the in vitro latency-reversing effect of N-803 on primary human CD4+ T cells that were latently infected with HIV. These results advance our understanding of the mechanisms responsible for latency reversal and lentivirus reactivation during ART-suppressed infection.
Assuntos
Linfócitos T CD8-Positivos/imunologia , Interleucina-15/agonistas , Vírus da Imunodeficiência Símia/fisiologia , Replicação Viral , Animais , Linfócitos T CD4-Positivos/virologia , Infecções por HIV/imunologia , Infecções por HIV/virologia , Humanos , Interleucina-15/imunologia , Depleção Linfocítica , Macaca mulatta , Camundongos , Síndrome de Imunodeficiência Adquirida dos Símios/imunologia , Síndrome de Imunodeficiência Adquirida dos Símios/virologia , Latência Viral , Replicação Viral/imunologiaRESUMO
Long-lasting, latently infected resting CD4+ T cells are the greatest obstacle to obtaining a cure for HIV infection, as these cells can persist despite decades of treatment with antiretroviral therapy (ART). Estimates indicate that more than 70 years of continuous, fully suppressive ART are needed to eliminate the HIV reservoir1. Alternatively, induction of HIV from its latent state could accelerate the decrease in the reservoir, thus reducing the time to eradication. Previous attempts to reactivate latent HIV in preclinical animal models and in clinical trials have measured HIV induction in the peripheral blood with minimal focus on tissue reservoirs and have had limited effect2-9. Here we show that activation of the non-canonical NF-κB signalling pathway by AZD5582 results in the induction of HIV and SIV RNA expression in the blood and tissues of ART-suppressed bone-marrow-liver-thymus (BLT) humanized mice and rhesus macaques infected with HIV and SIV, respectively. Analysis of resting CD4+ T cells from tissues after AZD5582 treatment revealed increased SIV RNA expression in the lymph nodes of macaques and robust induction of HIV in almost all tissues analysed in humanized mice, including the lymph nodes, thymus, bone marrow, liver and lung. This promising approach to latency reversal-in combination with appropriate tools for systemic clearance of persistent HIV infection-greatly increases opportunities for HIV eradication.
Assuntos
Infecções por HIV/virologia , HIV-1/fisiologia , NF-kappa B/metabolismo , Síndrome de Imunodeficiência Adquirida dos Símios/virologia , Vírus da Imunodeficiência Símia/fisiologia , Latência Viral , Alcinos/farmacologia , Animais , Antirretrovirais/farmacologia , Infecções por HIV/metabolismo , HIV-1/efeitos dos fármacos , Macaca mulatta , Camundongos , Oligopeptídeos/farmacologia , Síndrome de Imunodeficiência Adquirida dos Símios/metabolismo , Vírus da Imunodeficiência Símia/efeitos dos fármacos , Latência Viral/efeitos dos fármacosRESUMO
Lifelong treatment is required for people living with HIV as current antiretroviral therapy (ART) does not eradicate HIV infection. Latently infected cells are essentially indistinguishable from uninfected cells and cannot be depleted by currently available approaches. This study evaluated antibody mediated transient CD4+ T cell depletion as a strategy to reduce the latent HIV reservoir. Anti-CD4 antibodies effectively depleted CD4+ T cells in the peripheral blood and tissues of humanized mice. We then demonstrate that antibody-mediated CD4+ T cell depletion of HIV infected ART-suppressed animals results in substantial reductions in cell-associated viral RNA and DNA levels in peripheral blood cells over the course of anti-CD4 antibody treatment. Recovery of CD4+ T cells was observed in all tissues analyzed except for the lung 26 days after cessation of antibody treatment. After CD4+ T cell recovery, significantly lower levels of cell-associated viral RNA and DNA were detected in the tissues of anti-CD4 antibody-treated animals. Further, an 8.5-fold reduction in the levels of intact HIV proviral DNA and a 3.1-fold reduction in the number of latently infected cells were observed in anti-CD4-antibody-treated animals compared with controls. However, there was no delay in viral rebound when ART was discontinued in anti-CD4 antibody-treated animals following CD4+ T cell recovery compared with controls. Our results suggest that transient CD4+ T cell depletion, a long-standing clinical intervention that might have an acceptable safety profile, during suppressive ART can reduce the size of the HIV reservoir in humanized mice.
Assuntos
Infecções por HIV , HIV-1 , Humanos , Camundongos , Animais , Linfócitos T CD4-Positivos , Latência Viral , Replicação Viral , Antirretrovirais/farmacologia , Antirretrovirais/uso terapêutico , RNA Viral , DNA , Carga ViralRESUMO
BACKGROUND: Since the introduction of combination antiretroviral therapy (cART) the brain has become an important human immunodeficiency virus (HIV) reservoir due to the relatively low penetration of many drugs utilized in cART into the central nervous system (CNS). Given the inherent limitations of directly assessing acute HIV infection in the brains of people living with HIV (PLWH), animal models, such as humanized mouse models, offer the most effective means of studying the effects of different viral strains and their impact on HIV infection in the CNS. To evaluate CNS pathology during HIV-1 infection in the humanized bone marrow/liver/thymus (BLT) mouse model, a histological analysis was conducted on five CNS regions, including the frontal cortex, hippocampus, striatum, cerebellum, and spinal cord, to delineate the neuronal (MAP2ab, NeuN) and neuroinflammatory (GFAP, Iba-1) changes induced by two viral strains after 2 weeks and 8 weeks post-infection. RESULTS: Findings reveal HIV-infected human cells in the brain of HIV-infected BLT mice, demonstrating HIV neuroinvasion. Further, both viral strains, HIV-1JR-CSF and HIV-1CH040, induced neuronal injury and astrogliosis across all CNS regions following HIV infection at both time points, as demonstrated by decreases in MAP2ab and increases in GFAP fluorescence signal, respectively. Importantly, infection with HIV-1JR-CSF had more prominent effects on neuronal health in specific CNS regions compared to HIV-1CH040 infection, with decreasing number of NeuN+ neurons, specifically in the frontal cortex. On the other hand, infection with HIV-1CH040 demonstrated more prominent effects on neuroinflammation, assessed by an increase in GFAP signal and/or an increase in number of Iba-1+ microglia, across CNS regions. CONCLUSION: These findings demonstrate that CNS pathology is widespread during acute HIV infection. However, neuronal loss and the magnitude of neuroinflammation in the CNS is strain dependent indicating that strains of HIV cause differential CNS pathologies.
Assuntos
Modelos Animais de Doenças , Infecções por HIV , HIV-1 , Doenças Neuroinflamatórias , Neurônios , Animais , Camundongos , Infecções por HIV/virologia , Infecções por HIV/patologia , Infecções por HIV/complicações , Humanos , Neurônios/virologia , Neurônios/patologia , Doenças Neuroinflamatórias/patologia , Doenças Neuroinflamatórias/virologia , Encéfalo/patologia , Encéfalo/virologia , Proteína Glial Fibrilar Ácida/metabolismo , Proteínas de Ligação ao Cálcio/metabolismo , Proteínas dos Microfilamentos/metabolismoRESUMO
HIV-associated neurological disorders (HAND) affect up to 50% of people living with HIV (PLWH), even in the era of combination antiretroviral therapy (cART). HIV-DNA can be detected in the cerebral spinal fluid (CSF) of approximately half of aviremic ART-suppressed PLWH and its presence is associated with poorer neurocognitive performance. HIV DNA + and HIV RNA + cells have also been observed in postmortem brain tissue of individuals with sustained cART suppression. In this review, we provide an overview of how HIV invades the brain and HIV infection of resident brain glial cells (astrocytes and microglia). We also discuss the role of resident glial cells in persistent neuroinflammation and HAND in PLWH and their potential contribution to the HIV reservoir. HIV eradication strategies that target persistently infected glia cells will likely be needed to achieve HIV cure.
Assuntos
Infecções por HIV , Doenças do Sistema Nervoso , Humanos , Infecções por HIV/complicações , Encéfalo , Macrófagos , HIV , MonócitosRESUMO
BACKGROUND: Approximately 1.5 million HIV-positive women become pregnant annually. Without treatment, up to 45% will transmit HIV to their infants, primarily through breastfeeding. These numbers highlight that HIV acquisition is a major health concern for women and children globally. They also emphasize the urgent need for novel approaches to prevent HIV acquisition that are safe, effective and convenient to use by women and children in places where they are most needed. METHODS: 4'-Ethynyl-2-fluoro-2'-deoxyadenosine, a potent NRTI with low cytotoxicity, was administered orally to NOD/SCID/γc-/- mice and to bone marrow/liver/thymus (BLT) humanized mice, a preclinical model of HIV infection. HIV inhibitory activity in serum, cervicovaginal secretions and saliva was evaluated 4 h after administration. 4'-Ethynyl-2-fluoro-2'-deoxyadenosine's ability to prevent vaginal and oral HIV transmission was evaluated using highly relevant transmitted/founder viruses in BLT mice. RESULTS: Strong HIV inhibitory activity in serum, cervicovaginal secretions and saliva obtained from animals after a single oral dose of 4'-ethynyl-2-fluoro-2'-deoxyadenosine (10 mg/kg) demonstrated efficient drug penetration into relevant mucosal sites. A single daily oral dose of 4'-ethynyl-2-fluoro-2'-deoxyadenosine resulted in efficient prevention of vaginal and oral HIV transmission after multiple high-dose exposures to transmitted/founder viruses in BLT humanized mice. CONCLUSIONS: Our data demonstrated that 4'-ethynyl-2-fluoro-2'-deoxyadenosine efficiently prevents both vaginal and oral HIV transmission. Together with 4'-ethynyl-2-fluoro-2'-deoxyadenosine's relatively low toxicity and high potency against drug-resistant HIV strains, these data support further clinical development of 4'-ethynyl-2-fluoro-2'-deoxyadenosine as a potential pre-exposure prophylaxis agent to prevent HIV transmission in women and their infants.
Assuntos
Fármacos Anti-HIV/administração & dosagem , Desoxiadenosinas/administração & dosagem , Transmissão de Doença Infecciosa/prevenção & controle , Infecções por HIV/prevenção & controle , Boca/virologia , Profilaxia Pré-Exposição/métodos , Vagina/virologia , Animais , Secreções Corporais/virologia , Modelos Animais de Doenças , Feminino , Infecções por HIV/transmissão , Estudos Longitudinais , Camundongos , Camundongos SCIDRESUMO
UNLABELLED: Despite the nutritional and health benefits of breast milk, breast milk can serve as a vector for mother-to-child HIV transmission. Most HIV-infected infants acquire HIV through breastfeeding. Paradoxically, most infants breastfed by HIV-positive women do not become infected. This is potentially attributed to anti-HIV factors in breast milk. Breast milk of HIV-negative women can inhibit HIV infection. However, the HIV-inhibitory activity of breast milk from HIV-positive mothers has not been evaluated. In addition, while significant differences in breast milk composition between transmitting and nontransmitting HIV-positive mothers have been correlated with transmission risk, the HIV-inhibitory activity of their breast milk has not been compared. This knowledge may significantly impact the design of prevention approaches in resource-limited settings that do not deny infants of HIV-positive women the health benefits of breast milk. Here, we utilized bone marrow/liver/thymus humanized mice to evaluate the in vivo HIV-inhibitory activity of breast milk obtained from HIV-positive transmitting and nontransmitting mothers. We also assessed the species specificity and biochemical characteristics of milk's in vivo HIV-inhibitory activity and its ability to inhibit other modes of HIV infection. Our results demonstrate that breast milk of HIV-positive mothers has potent HIV-inhibitory activity and indicate that breast milk can prevent multiple routes of infection. Most importantly, this activity is unique to human milk. Our results also suggest multiple factors in breast milk may contribute to its HIV-inhibitory activity. Collectively, our results support current recommendations that HIV-positive mothers in resource-limited settings exclusively breastfeed in combination with antiretroviral therapy. IMPORTANCE: Approximately 240,000 children become infected with HIV annually, the majority via breastfeeding. Despite daily exposure to virus in breast milk, most infants breastfed by HIV-positive women do not acquire HIV. The low risk of breastfeeding-associated HIV transmission is likely due to antiviral factors in breast milk. It is well documented that breast milk of HIV-negative women can inhibit HIV infection. Here, we demonstrate, for the first time, that breast milk of HIV-positive mothers (nontransmitters and transmitters) inhibits HIV transmission. We also demonstrate that breast milk can prevent multiple routes of HIV acquisition and that this activity is unique to human milk. Collectively, our results support current guidelines which recommend that HIV-positive women in resource-limited settings exclusively breastfeed in combination with infant or maternal antiretroviral therapy.
Assuntos
Infecções por HIV/imunologia , Infecções por HIV/prevenção & controle , Infecções por HIV/transmissão , Transmissão Vertical de Doenças Infecciosas/prevenção & controle , Leite Humano/química , Animais , Western Blotting , Chlorocebus aethiops , Cromatografia Líquida de Alta Pressão , Eletroforese em Gel de Poliacrilamida , Feminino , Humanos , Transmissão Vertical de Doenças Infecciosas/estatística & dados numéricos , Macaca mulatta , Camundongos , Leite Humano/imunologia , Especificidade da Espécie , ZâmbiaRESUMO
We used bone marrow/liver/thymus (BLT) humanized mice to establish the effect of semen on vaginal HIV infection and on the efficacy of topically applied maraviroc. Our results demonstrate that vaginal transmission of cell-free HIV occurs efficiently in the presence of semen and that topically applied maraviroc efficiently prevents HIV transmission in the presence of semen. We also show that semen has no significant effect on the transmission of transmitted/founder viruses or cell-associated viruses.
Assuntos
Fármacos Anti-HIV/farmacologia , Cicloexanos/farmacologia , Infecções por HIV/prevenção & controle , HIV-1/efeitos dos fármacos , Sêmen/efeitos dos fármacos , Triazóis/farmacologia , Vagina/efeitos dos fármacos , Administração Intravaginal , Animais , Linfócitos T CD4-Positivos/efeitos dos fármacos , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/virologia , Modelos Animais de Doenças , Feminino , Infecções por HIV/imunologia , Infecções por HIV/transmissão , Infecções por HIV/virologia , HIV-1/fisiologia , Humanos , Masculino , Maraviroc , Camundongos , Camundongos Transgênicos , Sêmen/virologia , Vagina/imunologia , Vagina/virologia , Carga Viral/efeitos dos fármacosRESUMO
Over 90% of the adult human population is chronically infected with the Epstein-Barr virus (EBV), an oncogenic herpesvirus. EBV primarily infects naive human B cells and persists latently in memory B cells. Most individuals experience an asymptomatic infection that is effectively controlled by the adaptive immune response. However, EBV-associated lymphomas can develop in immunocompromised individuals. These tumors typically express all nine EBV latent proteins (latency III). Latency III is also associated with the expression of three precursor microRNAs (miRNAs) located within the EBV BHRF1 gene locus. The role of these BHRF1 miRNAs was unclear until recent in vitro studies demonstrated that they cooperate to enhance virus-induced B cell transformation and decrease the antigenic load of virus-infected cells, indicating that the BHRF1 miRNA cluster may serve as a novel therapeutic target for the treatment of latency III EBV-associated malignancies. However, to date, it is not known if BHRF1 miRNAs enhance virus-induced oncogenesis and/or immune evasion of EBV in vivo. To understand the in vivo contribution of the BHRF1 miRNA cluster to EBV infection and EBV-associated tumorigenesis, we monitored EBV infection and assessed tumor formation in humanized mice exposed to wild-type virus and a viral mutant (Δ123) that lacks all three BHRF1 miRNAs. Our results demonstrate that while the BHRF1 miRNAs facilitate the development of acute systemic EBV infection, they do not enhance the overall oncogenic potential of EBV in vivo.
Assuntos
Transformação Celular Neoplásica , Herpesvirus Humano 4/patogenicidade , Linfoma/virologia , MicroRNAs/metabolismo , Animais , Modelos Animais de Doenças , Herpesvirus Humano 4/genética , Linfoma/patologia , Camundongos , Camundongos SCID , MicroRNAs/genética , Infecções Tumorais por Vírus/genéticaRESUMO
Currently, over 15% of new HIV infections occur in children. Breastfeeding is a major contributor to HIV infections in infants. This represents a major paradox in the field because in vitro, breast milk has been shown to have a strong inhibitory effect on HIV infectivity. However, this inhibitory effect has never been demonstrated in vivo. Here, we address this important paradox using the first humanized mouse model of oral HIV transmission. We established that reconstitution of the oral cavity and upper gastrointestinal (GI) tract of humanized bone marrow/liver/thymus (BLT) mice with human leukocytes, including the human cell types important for mucosal HIV transmission (i.e. dendritic cells, macrophages and CD4⺠T cells), renders them susceptible to oral transmission of cell-free and cell-associated HIV. Oral transmission of HIV resulted in systemic infection of lymphoid and non-lymphoid tissues that is characterized by the presence of HIV RNA in plasma and a gradual decline of CD4⺠T cells in peripheral blood. Consistent with infection of the oral cavity, we observed virus shedding into saliva. We then evaluated the role of human breast milk on oral HIV transmission. Our in vivo results demonstrate that breast milk has a strong inhibitory effect on oral transmission of both cell-free and cell-associated HIV. Finally, we evaluated the effect of antiretrovirals on oral transmission of HIV. Our results show that systemic antiretrovirals administered prior to exposure can efficiently prevent oral HIV transmission in BLT mice.
Assuntos
Antirretrovirais/farmacologia , Infecções por HIV/transmissão , HIV-1/efeitos dos fármacos , Leite Humano , Boca/virologia , Animais , Linfócitos B/citologia , Linfócitos B/imunologia , Células Dendríticas/citologia , Células Dendríticas/imunologia , Duodeno/citologia , Duodeno/imunologia , Duodeno/virologia , Esôfago/citologia , Esôfago/imunologia , Esôfago/virologia , Infecções por HIV/imunologia , HIV-1/imunologia , Humanos , Macrófagos/citologia , Macrófagos/imunologia , Camundongos , Leite Humano/virologia , Boca/citologia , Boca/imunologia , Estômago/citologia , Estômago/imunologia , Estômago/virologia , Linfócitos T/citologia , Linfócitos T/imunologiaRESUMO
Respiratory syncytial virus (RSV) is a substantial cause of severe lower respiratory tract infections in infants, young children, older adults, and immunocompromised individuals. There is a vital need for effective therapeutics to prevent and/or treat severe RSV infection in these high-risk individuals. The development and pre-clinical testing of candidate RSV therapeutics could be accelerated by their evaluation in animals models that recapitulate bronchiolitis and bronchopneumonia; both hallmark features of severe RSV infection of humans. Previously, we demonstrated that implanted human lung tissue in humanized lung-only mice (LoM) can be infected with RSV resulting in a sustained virus replication. Here, we analyzed RSV-associated human lung pathology in the human lung implants of RSV-infected LoM. RSV infected epithelial cells lining the airway and alveolar regions of human lung implants resulting in hallmark histological features of RSV bronchiolitis and bronchopneumonia including distal airway and alveolar lumens clogged with 1) sloughed and necrotic RSV-infected epithelial cells, 2) neutrophil-containing inflammatory infiltrates, and 3) MUC5B dominated mucus secretions. We also show that treatment of LoM with a small molecule antiviral (ribavirin) or a neutralizing antibody (palivizumab) significantly suppressed and/or prevented RSV infection in vivo. Together, our data show that RSV infection of human lung implants in vivo has appropriate cellular tropism and results in hallmark pathological characteristics of severe bronchiolitis and bronchopneumonia in humans. They also offer proof-of-principle of the utility of this model to evaluate novel approaches for the prevention/treatment of RSV infection.
RESUMO
The HIV reservoir is more dynamic than previously thought with around 70% of the latent reservoir originating from viruses circulating within 1 year of the initiation of antiretroviral therapy (ART). In an ex vivo model system of HIV latency, it was reported that early exposure to class I histone deacetylase (HDAC) inhibitors might prevent these more recently infected cells from entering a state of stable viral latency. This finding raises the possibility that co-administration of HDAC inhibitors at the time of ART initiation may prevent the establishment of much of the HIV reservoir. Here, we tested the effects of the HDAC inhibitors suberoylanilide hydroxamic acid (SAHA) and panobinostat co-administered at the time of ART initiation on the formation of the viral reservoir in HIV-infected humanized mice. As previously shown, SAHA and panobinostat were well tolerated in humanized mice. Unexpectedly, co-administration of SAHA resulted in an increase in the frequency of CD4+ cells carrying HIV DNA but did not alter the frequency of cell-associated HIV RNA in HIV-infected, ART-treated humanized mice. Co-administration of panobinostat did not alter levels of cell-associated HIV DNA or RNA. Our in vivo findings indicate that co-administration of HDAC inhibitors initiated at the same time of ART treatment does not prevent recently infected cells from entering latency.IMPORTANCECurrent antiretroviral therapy (ART) does not eradicate cells harboring replication-competent HIV reservoir. Withdrawal of ART inevitably results in a rapid viremia rebound. The HIV reservoir is more dynamic than previously thought. Early exposure to class I histone deacetylase (HDAC) inhibitors inhibit these more recently infected cells from entering a state of stable viral latency in an ex vivo model of latency, raising the possibility that co-administration of HDAC inhibitors at the time of ART initiation may reduce much of the HIV reservoir. Here, we tested the effects of the HDAC inhibitors suberoylanilide hydroxamic acid or panobinostat during ART initiation on the formation of the viral reservoir in HIV-infected humanized mice. Our in vivo study indicates that in contrast to in vitro observations, the co-administration of HDAC inhibitors at the same time of ART initiation does not prevent recently infected cells from entering latency.
RESUMO
BACKGROUND: The major targets of HIV infection in humans are CD4⺠T cells. CD4⺠T cell depletion is a hallmark of AIDS. Previously, the SCID-hu thy/liv model was used to study the effect of HIV on thymopoeisis in vivo. However, these mice did not develop high levels of peripheral T cell reconstitution and required invasive surgery for infection and analysis. Here, we describe a novel variant of this model in which thy/liv implantation results in systemic reconstitution with human T cells in the absence of any other human hematopoietic lineages. RESULTS: NOD/SCID-hu thy/liv and NSG-hu thy/liv mice were created by implanting human fetal thymus and liver tissues under the kidney capsule of either NOD/SCID or NSG mice. In contrast to NOD/SCID-hu thy/liv mice that show little or no human cells in peripheral blood or tissues, substantial systemic human reconstitution occurs in NSG-hu thy/liv. These mice are exclusively reconstituted with human T cells (i.e. T-cell only mice or TOM). Despite substantial levels of human T cells no signs of graft-versus-host disease (GVHD) were noted in these mice over a period of 14 months. TOM are readily infected after parenteral exposure to HIV-1. HIV replication is sustained in peripheral blood at high levels and results in modest reduction of CD4⺠T cells. HIV-1 replication in TOM responds to daily administration of combination antiretroviral therapy (ART) resulting in strong suppression of virus replication as determined by undetectable viral load in plasma. Latently HIV infected resting CD4⺠T cells can be isolated from suppressed mice that can be induced to express HIV ex-vivo upon activation demonstrating the establishment of latency in vivo. CONCLUSIONS: NSG-hu thy/liv mice are systemically reconstituted with human T cells. No other human lymphoid lineages are present in these mice (i.e. monocytes/macrophages, B cells and DC are all absent). These T cell only mice do not develop GVHD, are susceptible to HIV-1 infection and can efficiently maintain virus replication. HIV infected TOM undergoing ART harbor latently infected, resting CD4+ T cells.
Assuntos
Modelos Animais de Doenças , Infecções por HIV/tratamento farmacológico , Infecções por HIV/virologia , HIV-1/fisiologia , Linfócitos T/imunologia , Linfócitos T/virologia , Latência Viral , Animais , Antirretrovirais/administração & dosagem , Humanos , Fígado/imunologia , Fígado/virologia , Camundongos , Camundongos SCID , Plasma/virologia , Timo/imunologia , Timo/virologia , Resultado do Tratamento , Carga ViralRESUMO
Here we demonstrate that a combination of tenofovir, emtricitabine, and raltegravir effectively suppresses peripheral and systemic HIV replication in humanized BLT mice. We also demonstrate that antiretroviral therapy (ART)-treated humanized BLT mice harbor latently infected resting human CD4+ T cells that can be induced ex vivo to produce HIV. We observed that the levels of infected resting human CD4+ T cells present in BLT mice are within the range of those observed circulating in patients undergoing suppressive ART. These results demonstrate the potential of humanized BLT mice as an attractive model for testing the in vivo efficacy of novel HIV eradication strategies.
Assuntos
Modelos Animais de Doenças , Infecções por HIV/virologia , HIV/fisiologia , Latência Viral , Animais , Fármacos Anti-HIV , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/virologia , HIV/efeitos dos fármacos , HIV/genética , Infecções por HIV/tratamento farmacológico , Infecções por HIV/imunologia , Humanos , Camundongos , Camundongos SCID , Latência Viral/efeitos dos fármacosRESUMO
Patr-AL is an expressed, non-polymorphic MHC class I gene carried by â¼50% of chimpanzee MHC haplotypes. Comparing Patr-AL(+) and Patr-AL(-) haplotypes showed Patr-AL defines a unique 125-kb genomic block flanked by blocks containing classical Patr-A and pseudogene Patr-H. Orthologous to Patr-AL are polymorphic orangutan Popy-A and the 5' part of human pseudogene HLA-Y, carried by â¼10% of HLA haplotypes. Thus, the AL gene alternatively evolved in these closely related species to become classical, nonclassical, and nonfunctional. Although differing by 30 aa substitutions in the peptide-binding α(1) and α(2) domains, Patr-AL and HLA-A*0201 bind overlapping repertoires of peptides; the overlap being comparable with that between the A*0201 and A*0207 subtypes differing by one substitution. Patr-AL thus has the A02 supertypic peptide-binding specificity. Patr-AL and HLA-A*0201 have similar three-dimensional structures, binding peptides in similar conformation. Although comparable in size and shape, the B and F specificity pockets of Patr-AL and HLA-A*0201 differ in both their constituent residues and contacts with peptide anchors. Uniquely shared by Patr-AL, HLA-A*0201, and other members of the A02 supertype are the absence of serine at position 9 in the B pocket and the presence of tyrosine at position 116 in the F pocket. Distinguishing Patr-AL from HLA-A*02 is an unusually electropositive upper face on the α(2) helix. Stimulating PBMCs from Patr-AL(-) chimpanzees with B cells expressing Patr-AL produced potent alloreactive CD8 T cells with specificity for Patr-AL and no cross-reactivity toward other MHC class I molecules, including HLA-A*02. In contrast, PBMCs from Patr-AL(+) chimpanzees are tolerant of Patr-AL.
Assuntos
Sequência Conservada/imunologia , Homologia de Genes/imunologia , Antígenos HLA-A/metabolismo , Antígenos de Histocompatibilidade Classe I/metabolismo , Peptídeos/metabolismo , Polimorfismo Genético , Animais , Sítios de Ligação/genética , Sítios de Ligação/imunologia , Clonagem Molecular , Sequência Conservada/genética , Antígenos HLA-A/química , Antígenos HLA-A/genética , Antígeno HLA-A2 , Antígenos de Histocompatibilidade Classe I/química , Antígenos de Histocompatibilidade Classe I/genética , Humanos , Dados de Sequência Molecular , Pan troglodytes , Peptídeos/química , Peptídeos/genética , Ligação Proteica/genética , Ligação Proteica/imunologia , Receptores de Antígenos de Linfócitos T/metabolismoRESUMO
HIV resistance to the Tat inhibitor didehydro-cortistatin A (dCA) in vitro correlates with higher levels of Tat-independent viral transcription and a seeming inability to enter latency, which rendered resistant isolates more susceptible to CTL-mediated immune clearance. Here, we investigated the ability of dCA-resistant viruses to replicate in vivo using a humanized mouse model of HIV infection. Animals were infected with WT or two dCA-resistant HIV-1 isolates in the absence of dCA and followed for 5 weeks. dCA-resistant viruses exhibited lower replication rates compared to WT. Viral replication was suppressed early after infection, with viral emergence at later time points. Multiplex analysis of cytokine and chemokines from plasma samples early after infection revealed no differences in expression levels between groups, suggesting that dCA-resistance viruses did not elicit potent innate immune responses capable of blocking the establishment of infection. Viral single genome sequencing results from plasma samples collected at euthanasia revealed that at least half of the total number of mutations in the LTR region of the HIV genome considered essential for dCA evasion reverted to WT. These results suggest that dCA-resistant viruses identified in vitro suffer a fitness cost in vivo, with mutations in LTR and Nef pressured to revert to wild type.
Assuntos
Infecções por HIV , Soropositividade para HIV , HIV-1 , Camundongos , Animais , Produtos do Gene tat do Vírus da Imunodeficiência Humana/genética , Produtos do Gene tat do Vírus da Imunodeficiência Humana/metabolismo , Infecções por HIV/tratamento farmacológico , HIV-1/fisiologia , Replicação Viral , Repetição Terminal Longa de HIVRESUMO
Respiratory syncytial virus (RSV) infection causes significant morbidity and mortality in infants, immunocompromised individuals, and older individuals. There is an urgent need for effective antivirals and vaccines for high-risk individuals. We used 2 complementary in vivo models to analyze RSV-associated human lung pathology and human immune correlates of protection. RSV infection resulted in widespread human lung epithelial damage, a proinflammatory innate immune response, and elicited a natural adaptive human immune response that conferred protective immunity. We demonstrated a key role for human T cells in controlling RSV infection. Specifically, primed human CD8+ T cells or CD4+ T cells effectively and independently control RSV replication in human lung tissue in the absence of an RSV-specific antibody response. These preclinical data support the development of RSV vaccines, which also elicit effective T cell responses to improve RSV vaccine efficacy.