RESUMEN
Human immunodeficiency virus (HIV) cure efforts are increasingly focused on harnessing CD8+ T cell functions, which requires a deeper understanding of CD8+ T cells promoting HIV control. Here we identifiy an antigen-responsive TOXhiTCF1+CD39+CD8+ T cell population with high expression of inhibitory receptors and low expression of canonical cytolytic molecules. Transcriptional analysis of simian immunodeficiency virus (SIV)-specific CD8+ T cells and proteomic analysis of purified CD8+ T cell subsets identified TOXhiTCF1+CD39+CD8+ T cells as intermediate effectors that retained stem-like features with a lineage relationship with terminal effector T cells. TOXhiTCF1+CD39+CD8+ T cells were found at higher frequency than TCF1-CD39+CD8+ T cells in follicular microenvironments and were preferentially located in proximity of SIV-RNA+ cells. Their frequency was associated with reduced plasma viremia and lower SIV reservoir size. Highly similar TOXhiTCF1+CD39+CD8+ T cells were detected in lymph nodes from antiretroviral therapy-naive and antiretroviral therapy-suppressed people living with HIV, suggesting this population of CD8+ T cells contributes to limiting SIV and HIV persistence.
Asunto(s)
Linfocitos T CD8-positivos , Ganglios Linfáticos , Síndrome de Inmunodeficiencia Adquirida del Simio , Virus de la Inmunodeficiencia de los Simios , Virus de la Inmunodeficiencia de los Simios/inmunología , Linfocitos T CD8-positivos/inmunología , Animales , Síndrome de Inmunodeficiencia Adquirida del Simio/inmunología , Síndrome de Inmunodeficiencia Adquirida del Simio/virología , Ganglios Linfáticos/inmunología , Humanos , Macaca mulatta , Infecciones por VIH/inmunología , Infecciones por VIH/virología , Subgrupos de Linfocitos T/inmunología , Subgrupos de Linfocitos T/metabolismoRESUMEN
SARS-CoV-2-induced hypercytokinemia and inflammation are critically associated with COVID-19 severity. Baricitinib, a clinically approved JAK1/JAK2 inhibitor, is currently being investigated in COVID-19 clinical trials. Here, we investigated the immunologic and virologic efficacy of baricitinib in a rhesus macaque model of SARS-CoV-2 infection. Viral shedding measured from nasal and throat swabs, bronchoalveolar lavages, and tissues was not reduced with baricitinib. Type I interferon (IFN) antiviral responses and SARS-CoV-2-specific T cell responses remained similar between the two groups. Animals treated with baricitinib showed reduced inflammation, decreased lung infiltration of inflammatory cells, reduced NETosis activity, and more limited lung pathology. Importantly, baricitinib-treated animals had a rapid and remarkably potent suppression of lung macrophage production of cytokines and chemokines responsible for inflammation and neutrophil recruitment. These data support a beneficial role for, and elucidate the immunological mechanisms underlying, the use of baricitinib as a frontline treatment for inflammation induced by SARS-CoV-2 infection.
Asunto(s)
Antiinflamatorios/administración & dosificación , Azetidinas/administración & dosificación , Tratamiento Farmacológico de COVID-19 , COVID-19/inmunología , Macaca mulatta , Infiltración Neutrófila/efectos de los fármacos , Purinas/administración & dosificación , Pirazoles/administración & dosificación , Sulfonamidas/administración & dosificación , Animales , COVID-19/fisiopatología , Muerte Celular/efectos de los fármacos , Degranulación de la Célula/efectos de los fármacos , Modelos Animales de Enfermedad , Inflamación/tratamiento farmacológico , Inflamación/genética , Inflamación/inmunología , Quinasas Janus/antagonistas & inhibidores , Pulmón/efectos de los fármacos , Pulmón/inmunología , Pulmón/patología , Activación de Linfocitos/efectos de los fármacos , Macrófagos Alveolares/inmunología , SARS-CoV-2/fisiología , Índice de Severidad de la Enfermedad , Linfocitos T/inmunología , Replicación Viral/efectos de los fármacosRESUMEN
HIV infection persists during antiretroviral therapy (ART) due to a reservoir of latently infected cells that harbor replication-competent virus and evade immunity. Previous ex vivo studies suggested that CD8+ T cells from people with HIV may suppress HIV expression via non-cytolytic mechanisms, but the mechanisms responsible for this effect remain unclear. Here, we used a primary cell-based in vitro latency model and demonstrated that co-culture of autologous activated CD8+ T cells with HIV-infected memory CD4+ T cells promoted specific changes in metabolic and/or signaling pathways resulting in increased CD4+ T cell survival, quiescence, and stemness. Collectively, these pathways negatively regulated HIV expression and ultimately promoted the establishment of latency. As shown previously, we observed that macrophages, but not B cells, promoted latency in CD4+ T cells. The identification of CD8-specific mechanisms of pro-latency activity may favor the development of approaches to eliminate the viral reservoir in people with HIV.
Asunto(s)
Infecciones por VIH , Humanos , Linfocitos T CD8-positivos , Latencia del Virus , Linfocitos T CD4-Positivos , Replicación ViralRESUMEN
Antiretroviral therapy (ART) suppresses viral replication in HIV-infected individuals but does not eliminate the reservoir of latently infected cells. Recent work identified PD-1+ follicular helper T (Tfh) cells as an important cellular compartment for viral persistence. Here, using ART-treated, SIV-infected rhesus macaques, we show that CTLA-4+PD-1- memory CD4+ T cells, which share phenotypic markers with regulatory T cells, were enriched in SIV DNA in blood, lymph nodes (LN), spleen, and gut, and contained replication-competent and infectious virus. In contrast to PD-1+ Tfh cells, SIV-enriched CTLA-4+PD-1- CD4+ T cells were found outside the B cell follicle of the LN, predicted the size of the persistent viral reservoir during ART, and significantly increased their contribution to the SIV reservoir with prolonged ART-mediated viral suppression. We have shown that CTLA-4+PD-1- memory CD4+ T cells are a previously unrecognized component of the SIV and HIV reservoir that should be therapeutically targeted for a functional HIV-1 cure.
Asunto(s)
Antirretrovirales/uso terapéutico , Linfocitos T CD4-Positivos/efectos de los fármacos , Antígeno CTLA-4/inmunología , Receptor de Muerte Celular Programada 1/inmunología , Síndrome de Inmunodeficiencia Adquirida del Simio/tratamiento farmacológico , Virus de la Inmunodeficiencia de los Simios/efectos de los fármacos , Animales , Linfocitos T CD4-Positivos/inmunología , Linfocitos T CD4-Positivos/virología , Antígeno CTLA-4/metabolismo , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/inmunología , Infecciones por VIH/virología , VIH-1/efectos de los fármacos , VIH-1/inmunología , VIH-1/fisiología , Interacciones Huésped-Patógeno/efectos de los fármacos , Interacciones Huésped-Patógeno/inmunología , Humanos , Memoria Inmunológica/efectos de los fármacos , Memoria Inmunológica/inmunología , Hibridación in Situ , Ganglios Linfáticos/efectos de los fármacos , Ganglios Linfáticos/inmunología , Ganglios Linfáticos/virología , Macaca mulatta , Microscopía Confocal , Receptor de Muerte Celular Programada 1/metabolismo , Síndrome de Inmunodeficiencia Adquirida del Simio/inmunología , Síndrome de Inmunodeficiencia Adquirida del Simio/virología , Virus de la Inmunodeficiencia de los Simios/inmunología , Virus de la Inmunodeficiencia de los Simios/fisiología , Linfocitos T Colaboradores-Inductores/efectos de los fármacos , Linfocitos T Colaboradores-Inductores/inmunología , Linfocitos T Colaboradores-Inductores/virología , Linfocitos T Reguladores/efectos de los fármacos , Linfocitos T Reguladores/inmunología , Linfocitos T Reguladores/virologíaRESUMEN
CD8 T cells are emerging as important mediators in atherosclerosis and cardiovascular disease (CVD). Immune activation may play a particular role in people with HIV (PWH) who are at an increased risk of CVD, even after controlling for known CVD risk factors. Latent CMV infection is associated with increased CVD risk for both PWH and people without HIV, and human CMV-specific CD4 and CD8 T cells are enriched for an immunosenescent phenotype. We previously showed that CMV coinfection in PWH promotes vascular homing and activation of inflammatory CD4 T cells through the CD2-LFA-3 axis. However, the role of CD2/LFA3 costimulation of CD8 T cells in PWH with CMV has yet to be described. In the present study, we demonstrate that CD2 expression on CX3CR1+CD57+CD28- inflammescent CD8 T cells is increased on cells from CMV-seropositive PWH. In vitro CD2/LFA-3 costimulation enhances TCR-mediated activation of these inflammatory CD8 memory T cells. Finally, we show that LFA-3 is highly expressed in aortas of SIV-infected rhesus macaques and in atherosclerotic plaques of people without HIV. Our findings are consistent with a model in which CMV infection enhances CD2 expression on highly proinflammatory CD8 T cells that can then be stimulated by LFA-3 expressed in the vasculature, even in the absence of CD28 costimulation. This model, in which CMV infection exacerbates toxic cytokine and granzyme production by CD8 T cells within the vasculature, highlights a potential therapeutic target in atherosclerosis development and progression, especially for PWH.
Asunto(s)
Aterosclerosis , Enfermedades Cardiovasculares , Infecciones por Citomegalovirus , Infecciones por VIH , Animales , Humanos , Antígenos CD28/metabolismo , Infecciones por VIH/tratamiento farmacológico , Citomegalovirus , Antígenos CD58/metabolismo , Macaca mulatta , Linfocitos T CD8-positivos , Linfocitos T CD4-Positivos , Aterosclerosis/metabolismoRESUMEN
An Amendment to this paper has been published and can be accessed via a link at the top of the paper.
RESUMEN
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.
Asunto(s)
Linfocitos T CD8-positivos/inmunología , Interleucina-15/agonistas , Virus de la Inmunodeficiencia de los Simios/fisiología , Replicación Viral , Animales , Linfocitos T CD4-Positivos/virología , Infecciones por VIH/inmunología , Infecciones por VIH/virología , Humanos , Interleucina-15/inmunología , Depleción Linfocítica , Macaca mulatta , Ratones , Síndrome de Inmunodeficiencia Adquirida del Simio/inmunología , Síndrome de Inmunodeficiencia Adquirida del Simio/virología , Latencia del Virus , Replicación Viral/inmunologíaRESUMEN
Interferons (IFNs) are essential for defense against viral infections but also drive recruitment of inflammatory cells to sites of infection, a key feature of severe COVID-19. Here, we explore the complexity of the IFN response in COVID-19, examine the effects of manipulating IFN on SARS-CoV-2 viral replication and pathogenesis, and highlight pre-clinical and clinical studies evaluating the therapeutic efficacy of IFN in limiting COVID-19 severity.
Asunto(s)
Antivirales , Tratamiento Farmacológico de COVID-19 , COVID-19 , Interferones , SARS-CoV-2 , Animales , Humanos , Antivirales/uso terapéutico , COVID-19/inmunología , COVID-19/virología , COVID-19/terapia , Interferones/uso terapéutico , Interferones/inmunología , SARS-CoV-2/efectos de los fármacos , SARS-CoV-2/inmunología , Replicación Viral/efectos de los fármacosRESUMEN
One approach to 'functional cure' of HIV infection is to induce durable control of HIV replication after the interruption of antiretroviral therapy (ART). However, the major factors that determine the viral 'setpoint' level after treatment interruption are not well understood. Here we combine data on ART interruption following SIV infection for 124 total animals from 10 independent studies across 3 institutional cohorts to understand the dynamics and predictors of post-treatment viral control. We find that the timing of treatment initiation is an important determinant of both the peak and early setpoint viral levels after treatment interruption. During the first 3 weeks of infection, every day of delay in treatment initiation is associated with a 0.22 log10 copies/ml decrease in post-rebound peak and setpoint viral levels. However, delay in initiation of ART beyond 3 weeks of infection is associated with higher post-rebound setpoint viral levels. For animals treated beyond 3 weeks post-infection, viral load at ART initiation was the primary predictor of post-rebound setpoint viral levels. Potential alternative predictors of post-rebound setpoint viral loads including cell-associated DNA or RNA, time from treatment interruption to rebound, and pre-interruption CD8+ T cell responses were also examined in the studies where these data were available. This analysis suggests that optimal timing of treatment initiation may be an important determinant of post-treatment control of HIV.
Asunto(s)
Infecciones por VIH , Animales , Infecciones por VIH/tratamiento farmacológico , Linfocitos T CD8-positivos , ARN Viral , Carga Viral , Antirretrovirales/farmacología , Antirretrovirales/uso terapéuticoRESUMEN
HIV-associated neurocognitive disorders (HAND) affect ~40% of virally suppressed people with HIV (PWH), however, the precise viral dependent and independent changes to the brain are unclear. Here we characterized the CNS reservoir and immune environment of SIV-infected (SIV+) rhesus macaques during acute (n = 4), chronic (n = 12) or ART-suppressed SIV infection (n = 11). Multiplex immunofluorescence for markers of SIV infection (vRNA/vDNA) and immune activation was performed on frontal cortex and matched colon tissue. SIV+ animals contained detectable viral DNA+ cells that were not reduced in the frontal cortex or the gut by ART, supporting the presence of a stable viral reservoir in these compartments. SIV+ animals had impaired blood brain barrier (BBB) integrity and heightened levels of astrocytes or myeloid cells expressing antiviral, anti-inflammatory or oxidative stress markers which were not abrogated by ART. Neuroinflammation and BBB dysfunction correlated with measures of viremia and immune activation in the gut. Furthermore, SIV-uninfected animals with experimentally induced gut damage and colitis showed a similar immune activation profile in the frontal cortex to those of SIV-infected animals, supporting the role of chronic gut damage as an independent source of neuroinflammation. Together, these findings implicate gut-associated immune activation/damage as a significant contributor to neuroinflammation in ART-suppressed HIV/SIV infection which may drive HAND pathogenesis.
Asunto(s)
Infecciones por VIH , Síndrome de Inmunodeficiencia Adquirida del Simio , Virus de la Inmunodeficiencia de los Simios , Animales , Síndrome de Inmunodeficiencia Adquirida del Simio/tratamiento farmacológico , Macaca mulatta , Enfermedades NeuroinflamatoriasRESUMEN
HIV rapidly rebounds after interruption of antiretroviral therapy (ART). HIV-specific CD8+ T cells may act to prevent early events in viral reactivation. However, the presence of viral immune escape mutations may limit the effect of CD8+ T cells on viral rebound. Here, we studied the impact of CD8 immune pressure on post-treatment rebound of barcoded SIVmac293M in 14 Mamu-A*01 positive rhesus macaques that initiated ART on day 14, and subsequently underwent two analytic treatment interruptions (ATIs). Rebound following the first ATI (seven months after ART initiation) was dominated by virus that retained the wild-type sequence at the Mamu-A*01 restricted Tat-SL8 epitope. By the end of the two-month treatment interruption, the replicating virus was predominantly escaped at the Tat-SL8 epitope. Animals reinitiated ART for 3 months prior to a second treatment interruption. Time-to-rebound and viral reactivation rate were significantly slower during the second treatment interruption compared to the first. Tat-SL8 escape mutants dominated early rebound during the second treatment interruption, despite the dominance of wild-type virus in the proviral reservoir. Furthermore, the escape mutations detected early in the second treatment interruption were well predicted by those replicating at the end of the first, indicating that escape mutant virus in the second interruption originated from the latent reservoir as opposed to evolving de novo post rebound. SL8-specific CD8+ T cell levels in blood prior to the second interruption were marginally, but significantly, higher (median 0.73% vs 0.60%, p = 0.016). CD8+ T cell depletion approximately 95 days after the second treatment interruption led to the reappearance of wild-type virus. This work suggests that CD8+ T cells can actively suppress the rebound of wild-type virus, leading to the dominance of escape mutant virus after treatment interruption.
Asunto(s)
Infecciones por VIH , Síndrome de Inmunodeficiencia Adquirida del Simio , Virus de la Inmunodeficiencia de los Simios , Animales , Macaca mulatta , Replicación Viral/fisiología , Linfocitos T CD8-positivos , Epítopos , Carga Viral , Antirretrovirales/uso terapéutico , Antirretrovirales/farmacologíaRESUMEN
Infection with HIV persists despite suppressive antiretroviral therapy (ART), and treatment interruption results in rapid viral rebound. Antibody-mediated CD8(+) lymphocyte depletion in simian immunodeficiency virus (SIV)-infected rhesus macaques (RMs) shows that these cells contribute to viral control in untreated animals. However, the contribution of CD8(+) lymphocytes to maintaining viral suppression under ART remains unknown. Here, we have shown that in SIV-infected RMs treated with short-term (i.e., 8-32 week) ART, depletion of CD8(+) lymphocytes resulted in increased plasma viremia in all animals and that repopulation of CD8(+) T cells was associated with prompt reestablishment of virus control. Although the number of SIV-DNA-positive cells remained unchanged after CD8 depletion and reconstitution, the frequency of SIV-infected CD4(+) T cells before depletion positively correlated with both the peak and area under the curve of viremia after depletion. These results suggest a role for CD8(+) T cells in controlling viral production during ART, thus providing a rationale for exploring immunotherapeutic approaches in ART-treated HIV-infected individuals.
Asunto(s)
Antirretrovirales/farmacología , Linfocitos T CD8-positivos/inmunología , Síndrome de Inmunodeficiencia Adquirida del Simio/tratamiento farmacológico , Síndrome de Inmunodeficiencia Adquirida del Simio/inmunología , Virus de la Inmunodeficiencia de los Simios/inmunología , Animales , Anticuerpos Antivirales/inmunología , Terapia Antirretroviral Altamente Activa/métodos , Linfocitos T CD4-Positivos/efectos de los fármacos , Linfocitos T CD4-Positivos/inmunología , Linfocitos T CD8-positivos/efectos de los fármacos , Femenino , Depleción Linfocítica/métodos , Macaca mulatta , Masculino , Síndrome de Inmunodeficiencia Adquirida del Simio/virología , Virus de la Inmunodeficiencia de los Simios/efectos de los fármacos , Carga Viral/efectos de los fármacos , Carga Viral/inmunología , Viremia/tratamiento farmacológico , Viremia/inmunología , Viremia/virología , Replicación Viral/efectos de los fármacos , Replicación Viral/inmunologíaRESUMEN
Elucidating the mechanisms underlying the persistence and location of the HIV reservoir is critical for developing cure interventions. While it has been shown that levels of T-cell activation and the size of the HIV reservoir are greater in rectal tissue and lymph nodes (LN) than in blood, the relative contributions of T-cell subsets to this anatomic difference are unknown. We measured and compared HIV-1 DNA content, expression of the T-cell activation markers CD38 and HLA-DR, and expression of the exhaustion markers programmed cell death protein 1 (PD-1) and T-cell immunoreceptor with immunoglobulin and immunoreceptor tyrosine-based inhibitory motif domains (TIGIT) in naive, central memory (CM), transitional memory (TM), and effector memory (EM) CD4+ and CD8+ T-cells in paired blood and LN samples among 14 people with HIV who were receiving antiretroviral therapy. HIV-1 DNA levels, T-cell immune activation, and TIGIT expression were higher in LN than in blood, especially in CM and TM CD4+ T-cell subsets. Immune activation was significantly higher in all CD8+ T-cell subsets, and memory CD8+ T-cell subsets from LN had higher levels of PD-1 expression, compared with blood, while TIGIT expression levels were significantly lower in TM CD8+ T-cells. The differences seen in CM and TM CD4+ T-cell subsets were more pronounced among participants with CD4+ T-cell counts of <500 cells/µL within 2 years after antiretroviral therapy initiation, thus highlighting increased residual dysregulation in LN as a distinguishing feature of and a potential mechanism for individuals with suboptimal CD4+ T-cell recovery during antiretroviral therapy. IMPORTANCE This study provides new insights into the contributions of different CD4+ and CD8+ T-cell subsets to the anatomic differences between LN and blood in individuals with HIV who have optimal versus suboptimal CD4+ T-cell recovery. To our knowledge, this is the first study comparing paired LN and blood CD4+ and CD8+ T-cell differentiation subsets, as well as those subsets in immunological responders versus immunological suboptimal responders.
Asunto(s)
Linfocitos T CD4-Positivos , Linfocitos T CD8-positivos , ADN Viral , Infecciones por VIH , Ganglios Linfáticos , Activación de Linfocitos , Humanos , Ganglios Linfáticos/citología , Ganglios Linfáticos/inmunología , Ganglios Linfáticos/virología , ADN Viral/análisis , VIH-1 , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/virología , Sangre/inmunología , Sangre/virología , Activación de Linfocitos/inmunología , Linfocitos T CD4-Positivos/inmunología , Linfocitos T CD4-Positivos/virología , Linfocitos T CD8-positivos/inmunología , Linfocitos T CD8-positivos/virología , Masculino , Adulto , Persona de Mediana Edad , Receptor de Muerte Celular Programada 1/genética , Receptor de Muerte Celular Programada 1/metabolismo , Subgrupos de Linfocitos T/inmunología , Subgrupos de Linfocitos T/virologíaRESUMEN
CD4+ T follicular helper (TFH) cells are key targets for human immunodeficiency virus (HIV)/simian immunodeficiency virus (SIV) replication and contribute to the virus reservoir under antiretroviral therapy (ART). Here, we describe a novel CD3+ CD20+ double-positive (DP) lymphocyte subset, resident in secondary lymphoid organs of humans and rhesus macaques (RMs), that appear predominantly after membrane exchange between TFH and B cells. DP lymphocytes are enriched in cells displaying a TFH phenotype (CD4+ PD1hi CXCR5hi), function (interleukin 21 positive [IL-21+]), and gene expression profile. Importantly, expression of CD40L upon brief in vitro mitogen stimulation identifies, by specific gene-expression signatures, DP cells of TFH-cell origin versus those of B-cell origin. Analysis of 56 RMs showed that DP cells (i) significantly increase following SIV infection, (ii) are reduced after 12 months of ART in comparison to pre-ART levels, and (iii) expand to a significantly higher frequency following ART interruption. Quantification of total SIV-gag DNA on sorted DP cells from chronically infected RMs showed that these cells are susceptible to SIV infection. These data reinforce earlier observations that CD20+ T cells are infected and expanded by HIV infection, while suggesting that these cells phenotypically overlap activated CD4+ TFH cells that acquire CD20 expression via trogocytosis and can be targeted as part of therapeutic strategies aimed at HIV remission. IMPORTANCE The HIV reservoir is largely composed of latently infected memory CD4+ T cells that persist during antiretroviral therapy and constitute a major barrier toward HIV eradication. In particular, CD4+ T follicular helper cells have been demonstrated as key targets for viral replication and persistence under ART. In lymph nodes from HIV-infected humans and SIV-infected rhesus macaques, we show that CD3+ CD20+ lymphocytes emerge after membrane exchange between T cells and B cells and are enriched in phenotypic, functional, and gene expression profiles found in T follicular helper cells. Furthermore, in SIV-infected rhesus macaques, these cells expand following experimental infection and after interruption of ART and harbor SIV DNA at levels similar to those found in CD4+ T cells; thus, CD3+ CD20+ lymphocytes are susceptible to SIV infection and can contribute to SIV persistence.
Asunto(s)
Síndrome de Inmunodeficiencia Adquirida del Simio , Virus de la Inmunodeficiencia de los Simios , Células T Auxiliares Foliculares , Animales , Humanos , Linfocitos T CD4-Positivos/inmunología , Linfocitos T CD4-Positivos/virología , Infecciones por VIH/inmunología , Infecciones por VIH/virología , Ganglios Linfáticos/citología , Macaca mulatta , Síndrome de Inmunodeficiencia Adquirida del Simio/inmunología , Síndrome de Inmunodeficiencia Adquirida del Simio/virología , Virus de la Inmunodeficiencia de los Simios/genética , Células T Auxiliares Foliculares/inmunología , Células T Auxiliares Foliculares/virología , Linfocitos B/inmunología , Linfocitos B/virología , Ligando de CD40/genética , Expresión Génica/inmunología , ADN Viral/metabolismo , Tejido Linfoide/citología , Tejido Linfoide/inmunología , Tejido Linfoide/virologíaRESUMEN
Despite the advent of effective antiretroviral therapy (ART), human immunodeficiency virus (HIV) continues to pose major challenges, with extensive pathogenesis during acute and chronic infection prior to ART initiation and continued persistence in a reservoir of infected CD4 T cells during long-term ART. CD101 has recently been characterized to play an important role in CD4 Treg potency. Using the simian immunodeficiency virus (SIV) model of HIV infection in rhesus macaques, we characterized the role and kinetics of CD101+ CD4 T cells in longitudinal SIV infection. Phenotypic analyses and single-cell RNAseq profiling revealed that CD101 marked CD4 Tregs with high immunosuppressive potential, distinct from CD101- Tregs, and these cells also were ideal target cells for HIV/SIV infection, with higher expression of CCR5 and α4ß7 in the gut mucosa. Notably, during acute SIV infection, CD101+ CD4 T cells were preferentially depleted across all CD4 subsets when compared with their CD101- counterpart, with a pronounced reduction within the Treg compartment, as well as significant depletion in mucosal tissue. Depletion of CD101+ CD4 was associated with increased viral burden in plasma and gut and elevated levels of inflammatory cytokines. While restored during long-term ART, the reconstituted CD101+ CD4 T cells display a phenotypic profile with high expression of inhibitory receptors (including PD-1 and CTLA-4), immunsuppressive cytokine production, and high levels of Ki-67, consistent with potential for homeostatic proliferation. Both the depletion of CD101+ cells and phenotypic profile of these cells found in the SIV model were confirmed in people with HIV on ART. Overall, these data suggest an important role for CD101-expressing CD4 T cells at all stages of HIV/SIV infection and a potential rationale for targeting CD101 to limit HIV pathogenesis and persistence, particularly at mucosal sites.
Asunto(s)
Infecciones por VIH , Síndrome de Inmunodeficiencia Adquirida del Simio , Virus de la Inmunodeficiencia de los Simios , Animales , Linfocitos T CD4-Positivos , Infecciones por VIH/metabolismo , Humanos , Macaca mulattaRESUMEN
In contrast to infections with human immunodeficiency virus (HIV) in humans and simian immunodeficiency virus (SIV) in macaques, SIV infection of a natural host, sooty mangabeys (Cercocebus atys), is non-pathogenic despite high viraemia. Here we sequenced and assembled the genome of a captive sooty mangabey. We conducted genome-wide comparative analyses of transcript assemblies from C. atys and AIDS-susceptible species, such as humans and macaques, to identify candidates for host genetic factors that influence susceptibility. We identified several immune-related genes in the genome of C. atys that show substantial sequence divergence from macaques or humans. One of these sequence divergences, a C-terminal frameshift in the toll-like receptor-4 (TLR4) gene of C. atys, is associated with a blunted in vitro response to TLR-4 ligands. In addition, we found a major structural change in exons 3-4 of the immune-regulatory protein intercellular adhesion molecule 2 (ICAM-2); expression of this variant leads to reduced cell surface expression of ICAM-2. These data provide a resource for comparative genomic studies of HIV and/or SIV pathogenesis and may help to elucidate the mechanisms by which SIV-infected sooty mangabeys avoid AIDS.
Asunto(s)
Síndrome de Inmunodeficiencia Adquirida/genética , Cercocebus atys/genética , Cercocebus atys/virología , Predisposición Genética a la Enfermedad , Genoma/genética , Especificidad del Huésped/genética , Virus de la Inmunodeficiencia de los Simios , Síndrome de Inmunodeficiencia Adquirida/virología , Secuencia de Aminoácidos , Animales , Moléculas de Adhesión Celular/química , Moléculas de Adhesión Celular/genética , Moléculas de Adhesión Celular/metabolismo , Cercocebus atys/inmunología , Exones/genética , Femenino , Mutación del Sistema de Lectura/genética , Variación Genética , Genómica , VIH/patogenicidad , Humanos , Macaca/virología , Eliminación de Secuencia , Síndrome de Inmunodeficiencia Adquirida del Simio/genética , Síndrome de Inmunodeficiencia Adquirida del Simio/virología , Virus de la Inmunodeficiencia de los Simios/patogenicidad , Especificidad de la Especie , Receptor Toll-Like 4/química , Receptor Toll-Like 4/genética , Receptor Toll-Like 4/inmunología , Transcriptoma/genética , Secuenciación Completa del GenomaRESUMEN
Clinical outcomes are inferior for individuals with HIV having suboptimal CD4 T-cell recovery during antiretroviral therapy (ART). We investigated if the levels of infection and the response to homeostatic cytokines of CD4 T-cell subsets contributed to divergent CD4 T-cell recovery and HIV reservoir during ART by studying virologically-suppressed immunologic responders (IR, achieving a CD4 cell count >500 cells/µL on or before two years after ART initiation), and virologically-suppressed suboptimal responders (ISR, did not achieve a CD4 cell count >500 cells/µL in the first two years after ART initiation). Compared to IR, ISR demonstrated higher levels of HIV-DNA in naïve, central (CM), transitional (TM), and effector (EM) memory CD4 T-cells in blood, both pre- and on-ART, and specifically in CM CD4 T-cells in LN on-ART. Furthermore, ISR had higher pre-ART plasma levels of IL-7 and IL-15, cytokines regulating T-cell homeostasis. Notably, pre-ART PD-1 and TIGIT expression levels were higher in blood CM and TM CD4 T-cells for ISR; this was associated with a significantly lower fold-changes in HIV-DNA levels between pre- and on-ART time points exclusively on CM and TM T-cell subsets, but not naïve or EM T-cells. Finally, the frequency of CM CD4 T-cells expressing PD-1 or TIGIT pre-ART as well as plasma levels of IL-7 and IL-15 predicted HIV-DNA content on-ART. Our results establish the association between infection, T-cell homeostasis, and expression of PD-1 and TIGIT in long-lived CD4 T-cell subsets prior to ART with CD4 T-cell recovery and HIV persistence on-ART.
Asunto(s)
Antirretrovirales/farmacología , Linfocitos T CD4-Positivos/inmunología , Citocinas/metabolismo , Infecciones por VIH/virología , Homeostasis , Subgrupos de Linfocitos T/inmunología , Linfocitos T CD4-Positivos/efectos de los fármacos , Linfocitos T CD4-Positivos/virología , ADN Viral , Femenino , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/inmunología , VIH-1/inmunología , Humanos , Memoria Inmunológica/inmunología , Masculino , Persona de Mediana Edad , Subgrupos de Linfocitos T/efectos de los fármacos , Subgrupos de Linfocitos T/virología , Carga ViralRESUMEN
HIV associated immune activation (IA) is associated with increased morbidity in people living with HIV (PLWH) on antiretroviral therapy, and remains a barrier for strategies aimed at reducing the HIV reservoir. The underlying mechanisms of IA have not been definitively elucidated, however, persistent production of Type I IFNs and expression of ISGs is considered to be one of the primary factors. Plasmacytoid DCs (pDCs) are a major producer of Type I IFN during viral infections, and are highly immunomodulatory in acute HIV and SIV infection, however their role in chronic HIV/SIV infection has not been firmly established. Here, we performed a detailed transcriptomic characterization of pDCs in chronic SIV infection in rhesus macaques, and in sooty mangabeys, a natural host non-human primate (NHP) species that undergoes non-pathogenic SIV infection. We also investigated the immunostimulatory capacity of lymph node homing pDCs in chronic SIV infection by contrasting gene expression of pDCs isolated from lymph nodes with those from blood. We observed that pDCs in LNs, but not blood, produced high levels of IFNα transcripts, and upregulated gene expression programs consistent with T cell activation and exhaustion. We apply a novel strategy to catalogue uncharacterized surface molecules on pDCs, and identified the lymphoid exhaustion markers TIGIT and LAIR1 as highly expressed in SIV infection. pDCs from SIV-infected sooty mangabeys lacked the activation profile of ISG signatures observed in infected macaques. These data demonstrate that pDCs are a primary producer of Type I IFN in chronic SIV infection. Further, this study demonstrated that pDCs trafficking to LNs persist in a highly activated state well into chronic infection. Collectively, these data identify pDCs as a highly immunomodulatory cell population in chronic SIV infection, and a putative therapeutic target to reduce immune activation.
Asunto(s)
Células Dendríticas/inmunología , Síndrome de Inmunodeficiencia Adquirida del Simio/inmunología , Animales , Cercocebus atys , Perfilación de la Expresión Génica , Macaca mulatta , RNA-Seq , TranscriptomaRESUMEN
Inducing latency reversal to reveal infected cells to the host immune system represents a potential strategy to cure HIV infection. In separate studies, we have previously shown that CD8+ T cells may contribute to the maintenance of viral latency and identified a novel SMAC mimetic/IAP inhibitor (AZD5582) capable of reversing HIV/SIV latency in vivo by activating the non-canonical (nc) NF-κB pathway. Here, we use AZD5582 in combination with antibody-mediated depletion of CD8α+ cells to further evaluate the role of CD8+ T cells in viral latency maintenance. Six rhesus macaques (RM) were infected with SIVmac239 and treated with ART starting at week 8 post-infection. After 84-85 weeks of ART, all animals received a single dose of the anti-CD8α depleting antibody (Ab), MT807R1 (50mg/kg, s.c.), followed by 5 weekly doses of AZD5582 (0.1 mg/kg, i.v.). Following CD8α depletion + AZD5582 combined treatment, 100% of RMs experienced on-ART viremia above 60 copies per ml of plasma. In comparator groups of ART-suppressed SIV-infected RMs treated with AZD5582 only or CD8α depletion only, on-ART viremia was experienced by 56% and 57% of the animals respectively. Furthermore, the frequency of increased viremic episodes during the treatment period was greater in the CD8α depletion + AZD5582 group as compared to other groups. Mathematical modeling of virus reactivation suggested that, in addition to viral dynamics during acute infection, CD8α depletion influenced the response to AZD5582. This work suggests that the latency reversal induced by activation of the ncNF-κB signaling pathway with AZD5582 can be enhanced by CD8α+ cell depletion.
RESUMEN
MHC-I-restricted, virus-specific cytotoxic CD8+ T cells (CTLs) may control human immunodeficiency virus (HIV) and simian immunodeficiency virus (SIV) replication via the recognition and killing of productively infected CD4+ T cells. Several studies in SIV-infected macaques suggest that CD8+ T cells may also decrease virus production by suppressing viral transcription. Here, we show that non-HIV-specific, TCR-activated non-cytolytic CD8+ T cells suppress HIV transcription via a virus- and MHC-independent immunoregulatory mechanism that modulates CD4+ T cell proliferation and activation. We also demonstrate that this CD8+ T cell-mediated effect promotes the survival of infected CD4+ T cells harboring integrated, inducible virus. Finally, we used RNA sequencing and secretome analyses to identify candidate cellular pathways that are involved in the virus-silencing mediated by these CD8+ T cells. This study characterizes a previously undescribed mechanism of immune-mediated HIV silencing that may be involved in the establishment and maintenance of the reservoir under antiretroviral therapy and therefore represent a major obstacle to HIV eradication.