ABSTRACT
Human alphaherpesvirus 1 (HSV-1) establishes life-long latency in sensory neurons in trigeminal ganglia (TG), brainstem neurons, and other CNS neurons. Two important segments of the brainstem were examined in this study: principal sensory nucleus of the spinal trigeminal tract (Pr5) because it receives direct afferent inputs from TG, and locus coeruleus (LC) because it is indirectly connected to Pr5 and LC sends axonal projections to cortical structures, which may facilitate viral spread from brainstem to the brain. The only viral gene abundantly expressed during latency is the latency associated transcript (LAT). Previous studies revealed 8-week old female C57Bl/6 mice infected with a LAT null mutant (dLAT2903) versus wild-type (wt) HSV-1 exhibit higher levels of senescence markers and inflammation in LC of females. New studies revealed 1-year old mice latently infected with wt HSV-1 or dLAT2903 contained differences in neuroinflammation and senescence in Pr5 and LC versus young mice. In summary, these studies confirm HSV-1 promotes neuro-inflammation in the brainstem, which may accelerate neurodegenerative disease.
Subject(s)
Brain Stem , Herpesvirus 1, Human , Mice, Inbred C57BL , Neuroinflammatory Diseases , Virus Latency , Animals , Herpesvirus 1, Human/physiology , Herpesvirus 1, Human/genetics , Brain Stem/virology , Brain Stem/pathology , Mice , Female , Neuroinflammatory Diseases/virology , Neuroinflammatory Diseases/pathology , Herpes Simplex/virology , Herpes Simplex/pathology , Aging , Humans , Latent Infection/virology , Trigeminal Ganglion/virology , Disease Models, AnimalABSTRACT
Combinational antiretroviral therapy (cART) suppresses human immunodeficiency virus type 1 (HIV-1) viral replication and pathogenesis in acquired immunodeficiency syndrome (AIDS) patients. However, HIV-1 remains in the latent stage of infection by suppressing viral transcription, which hinders an HIV-1 cure. One approach for an HIV-1 cure is the "shock and kill" strategy. The strategy focuses on reactivating latent HIV-1, inducing the viral cytopathic effect and facilitating the immune clearance for the elimination of latent HIV-1 reservoirs. Here, we reported that the H3K4 trimethylation (H3K4me3)-specific demethylase KDM5A/B play a role in suppressing HIV-1 Tat/LTR-mediated viral transcription in HIV-1 latent cells. Furthermore, we evaluated the potential of KDM5-specific inhibitor JQKD82 as an HIV-1 "shock and kill" agent. Our results showed that JQKD82 increases the H3K4me3 level at HIV-1 5' LTR promoter regions, HIV-1 reactivation, and the cytopathic effects in an HIV-1-latent T cell model. In addition, we identified that the combination of JQKD82 and AZD5582, a non-canonical NF-κB activator, generates a synergistic impact on inducing HIV-1 lytic reactivation and cell death in the T cell. The latency-reversing potency of the JQKD82 and AZD5582 pair was also confirmed in peripheral blood mononuclear cells (PBMCs) isolated from HIV-1 aviremic patients and in an HIV-1 latent monocyte. In latently infected microglia (HC69) of the brain, either deletion or inhibition of KDM5A/B results in a reversal of the HIV-1 latency. Overall, we concluded that KDM5A/B function as a host repressor of the HIV-1 lytic reactivation and thus promote the latency and the survival of HIV-1 infected reservoirs.
Subject(s)
HIV Infections , HIV-1 , Virus Activation , Virus Latency , HIV-1/physiology , HIV-1/drug effects , HIV-1/genetics , Humans , Virus Latency/drug effects , HIV Infections/virology , HIV Infections/drug therapy , Virus Activation/drug effects , Retinoblastoma-Binding Protein 2/metabolism , Retinoblastoma-Binding Protein 2/genetics , Latent Infection/virology , Virus Replication/drug effects , HIV Long Terminal Repeat/genetics , Cell Survival , Cell Line , Histones/metabolism , Nuclear Proteins , Repressor Proteins , Jumonji Domain-Containing Histone DemethylasesABSTRACT
BACKGROUND: Chronic/latent viral infections may accelerate immunological aging, particularly among people living with HIV (PLWH). We characterized chronic/latent virus infections across their lifespan and investigated their associations with leukocyte telomere length (LTL). METHODS: Participants enrolled in the CARMA cohort study were randomly selected to include n = 15 for each decade of age between 0 and >60 y, for each sex, and each HIV status. Cytomegalovirus (CMV), Epstein-Barr virus (EBV), human herpesvirus 8 (HHV-8), herpes simplex virus 1 (HSV-1), and HSV-2 infection were determined serologically; HIV, hepatitis C (HCV), and hepatitis B (HBV) were self-reported. LTLs were measured using monochrome multiplex qPCR. Associations between the number of viruses, LTL, and sociodemographic factors were assessed using ordinal logistic and linear regression modeling. RESULTS: The study included 187 PLWH (105 female/82 male) and 190 HIV-negative participants (105 female/84 male), ranging in age from 0.7 to 76.1 years. Living with HIV, being older, and being female were associated with harbouring a greater number of chronic/latent non-HIV viruses. Having more infections was in turn bivariately associated with a shorter LTL. In multivariable analyses, older age, living with HIV, and the female sex remained independently associated with having more infections, while having 3-4 viruses (vs. 0-2) was associated with a shorter LTL. CONCLUSIONS: Our results suggest that persistent viral infections are more prevalent in PLWH and females, and that these may contribute to immunological aging. Whether this is associated with comorbidities later in life remains an important question.
Subject(s)
HIV Infections , Leukocytes , Humans , Female , HIV Infections/virology , HIV Infections/immunology , Male , Leukocytes/virology , Middle Aged , Adult , Aged , Young Adult , Adolescent , Child , Telomere/genetics , Infant , Child, Preschool , Latent Infection/virology , Virus Diseases/virology , Virus Diseases/immunology , Chronic Disease , Cohort Studies , Infant, NewbornABSTRACT
Despite antiretroviral therapy (ART), chronic forms of HIV-associated neurocognitive disorders (HAND) affect an estimated 50% of individuals living with HIV, greatly impacting their quality of life. The prevailing theory of HAND progression posits that chronic inflammation arising from the activation of latent viral reservoirs leads to progressive damage in the central nervous system (CNS). Recent evidence indicates that blood-brain barrier (BBB) pericytes are capable of active HIV-1 infection; however, their latent infection has not been defined. Given their location and function, BBB pericytes are poised to be a key viral reservoir in the development of HAND. We present the first transcriptional analysis of uninfected, active, and latent human BBB pericytes, revealing distinct transcriptional phenotypes. In addition, we demonstrate that latent infection of BBB pericytes relies on AKT signaling for reservoir survival. These findings provide insight into the state of reservoir maintenance in the CNS during HIV-1 infection and provide novel targets for reservoir clearance.
Subject(s)
Blood-Brain Barrier , Disease Reservoirs , HIV Infections , HIV-1 , Latent Infection , Pericytes , Humans , Blood-Brain Barrier/virology , HIV Infections/drug therapy , HIV Infections/transmission , HIV Infections/virology , Latent Infection/virology , Pericytes/virology , Proto-Oncogene Proteins c-akt/genetics , Quality of Life , Virus Latency , Disease Reservoirs/virologyABSTRACT
IMPORTANCE: To our knowledge, this is the first report delineating the activation of the master antioxidant defense during EBV latency. We show that EBV-triggered reactive oxygen species production activates the Keap1-NRF2 pathway in EBV-transformed cells, and LMP1 plays a major role in this event, and the stress-related kinase TBK1 is required for NRF2 activation. Moreover, we show that the Keap1-NRF2 pathway is important for cell proliferation and EBV latency maintenance. Our findings disclose how EBV controls the balance between oxidative stress and antioxidant defense, which greatly improve our understanding of EBV latency and pathogenesis and may be leveraged to opportunities toward the improvement of therapeutic outcomes in EBV-associated diseases.
Subject(s)
Antioxidants , Epstein-Barr Virus Infections , Herpesvirus 4, Human , Latent Infection , Virus Latency , Humans , Antioxidants/metabolism , Epstein-Barr Virus Infections/metabolism , Epstein-Barr Virus Infections/virology , Herpesvirus 4, Human/pathogenicity , Herpesvirus 4, Human/physiology , Kelch-Like ECH-Associated Protein 1/metabolism , Latent Infection/metabolism , Latent Infection/virology , NF-E2-Related Factor 2/metabolism , Oxidative Stress , Reactive Oxygen Species/metabolism , Cell ProliferationSubject(s)
Hematopoietic Stem Cell Transplantation , Hepatitis B , Latent Infection , Humans , Consensus , East Asian People , Hematopoietic Stem Cell Transplantation/adverse effects , Hepatitis B/etiology , Hepatitis B/prevention & control , Hepatitis B/virology , Hepatitis B Antibodies , Hepatitis B Surface Antigens , Hepatitis B virus/physiology , Virus Activation , Latent Infection/etiology , Latent Infection/virologySubject(s)
Antibodies, Monoclonal , Antineoplastic Agents , Hepatitis B , Latent Infection , Virus Activation , Humans , Antibodies, Monoclonal/adverse effects , Antibodies, Monoclonal/pharmacology , Antibodies, Monoclonal/therapeutic use , Antineoplastic Agents/adverse effects , Antineoplastic Agents/pharmacology , Antineoplastic Agents/therapeutic use , Hepatitis B/etiology , Hepatitis B/virology , Hepatitis B Antibodies , Hepatitis B Surface Antigens , Hepatitis B virus , Virus Activation/drug effects , Virus Activation/immunology , Latent Infection/etiology , Latent Infection/virologyABSTRACT
Epstein-Barr virus (EBV) has been identified as a putative trigger of multiple sclerosis (MS). Previously, we reported that mice latently infected with murine gammaherpesvirus 68 (γHV-68), the murine homolog to EBV, and induced for experimental autoimmune encephalomyelitis (EAE), developed an enhanced disease more reminiscent of MS. These prior results showed that expression of CD40 on CD11b+CD11c+ cells in latently infected mice was required to prime the strong Th1 response driving disease as well as decreasing Treg frequencies in the periphery and CNS. Subsequent work demonstrated that transfer of B cells from latently infected mice was sufficient to enhance disease. Herein, we show that B cells from infected mice do not need type I IFN signaling to drive a strong Th1 response, yet are important in driving infiltration of the CNS by CD8+ T cells. Given the importance of type I IFNs in MS, we used IFNARko mice in order to determine if type I IFN signaling was important in the enhancement of EAE in latently infected mice. We found that while type I IFNs are important for the control of γHV-68 infection and maintenance of latency, they do not have a direct effect in the development of enhanced EAE.
Subject(s)
Encephalomyelitis, Autoimmune, Experimental , Gammaherpesvirinae , Interferon Type I , Animals , CD8-Positive T-Lymphocytes , Encephalomyelitis, Autoimmune, Experimental/immunology , Latent Infection/immunology , Latent Infection/virology , MiceABSTRACT
Herpes simplex virus 1 (HSV-1) is a human pathogen capable of establishing lifelong latent infections that can reactivate under stress conditions. A viral immediate early protein that plays important roles in the HSV-1 lytic and latent infections is the viral E3 ubiquitin ligase, ICP0. ICP0 transactivates all temporal classes of HSV-1 genes and facilitates viral gene expression. ICP0 also impairs the antiviral effects of interferon (IFN)-ß, a component of host innate defenses known to limit viral replication. To begin to understand how ICP0 allows HSV-1 to disarm the IFN-ß response, we performed genetic analyses using a series of ICP0 truncation mutants in the absence and presence of IFN-ß in cell culture. We observed that IFN-ß pretreatment of cells significantly impaired the replication of the ICP0 truncation mutants, n212 and n312, which code for the first 211 and 311 amino acids of ICP0, respectively; this effect of IFN-ß correlated with decreased HSV-1 early and late gene expression. This increased sensitivity to IFN-ß was not as apparent with the ICP0 mutant, n389. Our mapping studies indicate that loss of 77 amino acids from residues 312 to 388 in the N-terminal half of ICP0 resulted in a virus that was significantly more sensitive to cells pre-exposed to IFN-ß. This 77 amino acid region contains a phospho-SUMO-interacting motif or -SIM, which we propose participates in ICP0's ability to counteract the antiviral response established by IFN-ß. IMPORTANCE Interferons (IFNs) are secreted cellular factors that are induced by viral infection and limit replication. HSV-1 is largely refractory to the antiviral effects of type 1 IFNs, which are synthesized shortly after viral infection, in part through the activities of the viral regulatory protein, ICP0. To understand how ICP0 impedes the antiviral effects of type 1 IFNs, we used a series of HSV-1 ICP0 mutants and examined their viral replication and gene expression levels in cells stimulated with IFN-ß (a type 1 IFN). Our mapping data identifies a discrete 77 amino acid region in the N-terminal half of ICP0 that facilitates HSV-1 resistance to IFN-ß. This region of ICP0 is modified by phosphorylation and binds to the posttranslational modification SUMO, suggesting that HSV, and potentially other viruses, may counteract type 1 IFN signaling by altering SUMO and/or SUMO modified cellular proteins.
Subject(s)
Herpesvirus 1, Human , Immediate-Early Proteins , Interferon Type I , Ubiquitin-Protein Ligases , Amino Acids , Antiviral Agents/pharmacology , Herpesvirus 1, Human/genetics , Humans , Immediate-Early Proteins/genetics , Interferon Type I/immunology , Latent Infection/virology , Ubiquitin-Protein Ligases/genetics , Viral Proteins/geneticsABSTRACT
Despite the clinical importance of latent human immunodeficiency virus type 1 (HIV-1) infection, our understanding of the biomolecular processes involved in HIV-1 latency control is still limited. This study was designed to address whether interactions between viral proteins, specifically HIV Nef, and the host cell could affect latency establishment. The study was driven by three reported observations. First, early reports suggested that human immunodeficiency virus type 2 (HIV-2) infection in patients produces a lower viral RNA/DNA ratio than HIV-1 infection, potentially indicating an increased propensity of HIV-2 to produce latent infection. Second, Nef, an early viral gene product, has been shown to alter the activation state of infected cells in a lentiviral lineage-dependent manner. Third, it has been demonstrated that the ability of HIV-1 to establish latent infection is a function of the activation state of the host cell at the time of infection. Based on these observations, we reasoned that HIV-2 Nef may have the ability to promote latency establishment. We demonstrate that HIV-1 latency establishment in T cell lines and primary T cells is indeed differentially modulated by Nef proteins. In the context of an HIV-1 backbone, HIV-1 Nef promoted active HIV-1 infection, while HIV-2 Nef strongly promoted latency establishment. Given that Nef represents the only difference in these HIV-1 vectors and is known to interact with numerous cellular factors, these data add support to the idea that latency establishment is a host cell-virus interaction phenomenon, but they also suggest that the HIV-1 lineage may have evolved mechanisms to counteract host cell suppression. IMPORTANCE Therapeutic attempts to eliminate the latent HIV-1 reservoir have failed, at least in part due to our incomplete biomolecular understanding of how latent HIV-1 infection is established and maintained. We here address the fundamental question of whether all lentiviruses actually possess a similar capacity to establish latent infections or whether there are differences between the lentiviral lineages driving differential latency establishment that could be exploited to develop improved latency reversal agents. Research investigating the viral RNA/DNA ratio in HIV-1 and HIV-2 patients could suggest that HIV-2 indeed has a much higher propensity to establish latent infections, a trait that we found, at least in part, to be attributable to the HIV-2 Nef protein. Reported Nef-mediated effects on host cell activation thus also affect latency establishment, and HIV-1 vectors that carry different lentiviral nef genes should become key tools to develop a better understanding of the biomolecular basis of HIV-1 latency establishment.
Subject(s)
HIV Infections , HIV-1 , Virus Latency , HIV Infections/metabolism , HIV Infections/virology , HIV-1/physiology , Host Microbial Interactions , Humans , Latent Infection/virology , RNA, Viral , Virus Latency/genetics , nef Gene Products, Human Immunodeficiency Virus/metabolismABSTRACT
The Varicella-zoster virus (VZV) or human herpes virus 3 is a neurotropic human alpha herpes virus responsible for chickenpox/varicella and shingles/Herpes zoster (HZ). This review will focus on HZ. Since HZ is secondary to varicella, its incidence increases with age. In children and youngsters, HZ is rare and associated to metabolic and neoplastic disorders. In adults, advanced age, distress, other infections (such as AIDS or COVID-19), and immunosuppression are the most common risk factors. HZ reactivation has recently been observed after COVID-19 vaccination. The disease shows different clinical stages of variable clinical manifestations. Some of the manifestations bear a higher risk of complications. Among the possible complications, postherpetic neuralgia, a chronic pain disease, is one of the most frequent. HZ vasculitis is associated with morbidity and mortality. Renal and gastrointestinal complications have been reported. The cornerstone of treatment is early intervention with acyclovir or brivudine. Second-line treatments are available. Pain management is essential. For (secondary) prophylaxis, currently two HZV vaccines are available for healthy older adults, a live attenuated VZV vaccine and a recombinant adjuvanted VZV glycoprotein E subunit vaccine. The latter allows vaccination also in severely immunosuppressed patients. This review focuses on manifestations of HZ and its management. Although several articles have been published on HZ, the literature continues to evolve, especially in regard to patients with comorbidities and immunocompromised patients. VZV reactivation has also emerged as an important point of discussion during the COVID-19 pandemic, especially after vaccination. The objective of this review is to discuss current updates related to clinical presentations, complications, and management of HZ.
Subject(s)
Disease Management , Herpes Zoster/drug therapy , Herpes Zoster/prevention & control , Herpesvirus 3, Human/pathogenicity , Herpesvirus Vaccines/immunology , Herpes Zoster/complications , Herpes Zoster/physiopathology , Herpesvirus Vaccines/administration & dosage , Herpesvirus Vaccines/classification , Humans , Immunocompromised Host , Incidence , Latent Infection/virology , Morbidity , Neuralgia, Postherpetic/virology , Risk Factors , Vaccination , Vaccines, Synthetic/administration & dosageSubject(s)
2019-nCoV Vaccine mRNA-1273/adverse effects , COVID-19/prevention & control , Herpesvirus 3, Human/physiology , Rheumatic Diseases/virology , Virus Activation/drug effects , 2019-nCoV Vaccine mRNA-1273/immunology , Adult , COVID-19/immunology , COVID-19/virology , Female , Herpes Zoster/chemically induced , Herpes Zoster/immunology , Herpes Zoster/virology , Humans , Immunomodulating Agents/adverse effects , Latent Infection/chemically induced , Latent Infection/immunology , Latent Infection/virology , Male , Middle Aged , Retrospective Studies , Rheumatic Diseases/drug therapy , Rheumatic Diseases/immunology , SARS-CoV-2/immunology , TaiwanABSTRACT
The main barrier to a cure for HIV is the persistence of long-lived and proliferating latently infected CD4+ T-cells despite antiretroviral therapy (ART). Latency is well characterized in multiple CD4+ T-cell subsets, however, the contribution of regulatory T-cells (Tregs) expressing FoxP3 as well as immune checkpoints (ICs) PD-1 and CTLA-4 as targets for productive and latent HIV infection in people living with HIV on suppressive ART is less well defined. We used multiplex detection of HIV DNA and RNA with immunohistochemistry (mIHC) on formalin-fixed paraffin embedded (FFPE) cells to simultaneously detect HIV RNA and DNA and cellular markers. HIV DNA and RNA were detected by in situ hybridization (ISH) (RNA/DNAscope) and IHC was used to detect cellular markers (CD4, PD-1, FoxP3, and CTLA-4) by incorporating the tyramide system amplification (TSA) system. We evaluated latently infected cell lines, a primary cell model of HIV latency and excisional lymph node (LN) biopsies collected from people living with HIV (PLWH) on and off ART. We clearly detected infected cells that coexpressed HIV RNA and DNA (active replication) and DNA only (latently infected cells) in combination with IHC markers in the in vitro infection model as well as LN tissue from PLWH both on and off ART. Combining ISH targeting HIV RNA and DNA with IHC provides a platform to detect and quantify HIV persistence within cells identified by multiple markers in tissue samples from PLWH on ART or to study HIV latency.
Subject(s)
DNA, Viral/analysis , HIV Infections/diagnosis , HIV/genetics , Immune Checkpoint Inhibitors/analysis , Immunohistochemistry , In Situ Hybridization , Latent Infection/diagnosis , Lymph Nodes/immunology , Lymph Nodes/virology , RNA, Viral/analysis , HIV Infections/immunology , HIV Infections/virology , Humans , Jurkat Cells , Latent Infection/immunology , Latent Infection/virology , Predictive Value of Tests , T-Lymphocytes, Regulatory/immunology , T-Lymphocytes, Regulatory/virologySubject(s)
Acyclovir/therapeutic use , Antiviral Agents/therapeutic use , Herpes Simplex/prevention & control , Latent Infection/prevention & control , Latent Infection/virology , Oropharynx/virology , Respiration, Artificial , Adult , Aged , Female , France , Humans , Male , Middle Aged , Retrospective Studies , Virus SheddingABSTRACT
The cGAS/STING/TBK1 (cyclic guanine monophosphate-AMP synthase/stimulator of interferon genes/Tank-binding kinase 1) innate immunity pathway is activated during human cytomegalovirus (HCMV) productive (lytic) replication in fully differentiated cells and during latency within incompletely differentiated myeloid cells. While multiple lytic-phase HCMV proteins neutralize steps along this pathway, none of them are expressed during latency. Here, we show that the latency-associated protein UL138 inhibits the cGAS/STING/TBK1 innate immunity pathway during transfections and infections, in fully differentiated cells and incompletely differentiated myeloid cells, and with loss of function and restoration of function approaches. UL138 inhibits the pathway downstream of STING but upstream of interferon regulatory factor 3 (IRF3) phosphorylation and NF-κB function and reduces the accumulation of interferon beta mRNA during both lytic and latent infections. IMPORTANCE While a cellular restriction versus viral countermeasure arms race between innate immunity and viral latency is expected, few examples have been documented. Our identification of the first HCMV latency protein that inactivates the cGAS/STING/TBK1 innate immune pathway opens the door to understanding how innate immunity, or its neutralization, impacts long-term persistence by HCMV and other latent viruses.
Subject(s)
Cytomegalovirus Infections , Cytomegalovirus , Interferon-beta , Membrane Proteins , Virus Latency , Humans , Cytomegalovirus/genetics , Cytomegalovirus/metabolism , Cytomegalovirus Infections/genetics , Cytomegalovirus Infections/immunology , Cytomegalovirus Infections/physiopathology , Cytomegalovirus Infections/virology , Host-Pathogen Interactions , Immunity, Innate , Interferon Regulatory Factor-3/genetics , Interferon Regulatory Factor-3/immunology , Interferon-beta/genetics , Interferon-beta/immunology , Latent Infection/genetics , Latent Infection/immunology , Latent Infection/virology , Membrane Proteins/genetics , Membrane Proteins/immunology , NF-kappa B/genetics , NF-kappa B/immunology , Protein Serine-Threonine Kinases/genetics , Protein Serine-Threonine Kinases/immunology , RNA, Messenger/genetics , RNA, Messenger/metabolism , Signal TransductionABSTRACT
Cytomegalovirus (CMV) viremia continues to cause significant morbidity and mortality in kidney transplant patients with clinical complications including organ rejection and death. Whole blood gene expression dynamics in CMV viremic patients from onset of DNAemia through convalescence has not been well studied to date in humans. To evaluate how CMV infection impacts whole blood leukocyte gene expression over time, we evaluated a matched cohort of 62 kidney transplant recipients with and without CMV DNAemia using blood samples collected at multiple time points during the 12-month period after transplant. While transcriptomic differences were minimal at baseline between DNAemic and non-DNAemic patients, hundreds of genes were differentially expressed at the long-term timepoint, including genes enriching for pathways important for macrophages, interferon, and IL-8 signaling. Amongst patients with CMV DNAemia, the greatest amount of transcriptomic change occurred between baseline and 1-week post-DNAemia, with increase in pathways for interferon signaling and cytotoxic T cell function. Time-course gene set analysis of these differentially expressed genes revealed that most of the enriched pathways had a significant time-trend. While many pathways that were significantly down- or upregulated at 1 week returned to baseline-like levels, we noted that several pathways important in adaptive and innate cell function remained upregulated at the long-term timepoint after resolution of CMV DNAemia. Differential expression analysis and time-course gene set analysis revealed the dynamics of genes and pathways involved in the immune response to CMV DNAemia in kidney transplant patients. Understanding transcriptional changes caused by CMV DNAemia may identify the mechanism behind patient vulnerability to CMV reactivation and increased risk of rejection in transplant recipients and suggest protective strategies to counter the negative immunologic impact of CMV. These findings provide a framework to identify immune correlates for risk assessment and guiding need for extending antiviral prophylaxis.
Subject(s)
Cytomegalovirus Infections , Cytomegalovirus/genetics , DNA, Viral/blood , Kidney Transplantation , Latent Infection , Transcriptome , Adult , Aged , Cytomegalovirus Infections/blood , Cytomegalovirus Infections/genetics , Cytomegalovirus Infections/virology , Female , Humans , Latent Infection/blood , Latent Infection/genetics , Latent Infection/virology , Male , Middle Aged , Transplant RecipientsABSTRACT
The HIV latent reservoir exhibits slow decay on antiretroviral therapy (ART), impacted by homeostatic proliferation and activation. How these processes contribute to the total dynamic while also producing the observed profile of sampled latent clone sizes is unclear. An agent-based model was developed that tracks individual latent clones, incorporating homeostatic proliferation of cells and activation of clones. The model was calibrated to produce observed latent reservoir dynamics as well as observed clonal size profiles. Simulations were compared to previously published latent HIV integration data from 5 adults and 3 children. The model simulations reproduced reservoir dynamics as well as generating residual plasma viremia levels (pVL) consistent with observations on ART. Over 382 Latin Hypercube Sample simulations, the median latent reservoir grew by only 0.3 log10 over the 10 years prior to ART initiation, after which time it decreased with a half-life of 15 years, despite number of clones decreasing at a faster rate. Activation produced a maximum size of genetically intact clones of around one million cells. The individual simulation that best reproduced the sampled clone profile, produced a reservoir that decayed with a 13.9 year half-life and where pVL, produced mainly from proliferation, decayed with a half-life of 10.8 years. These slow decay rates were achieved with mean cell life-spans of only 14.2 months, due to expansion of the reservoir through proliferation and activation. Although the reservoir decayed on ART, a number of clones increased in size more than 4,000-fold. While small sampled clones may have expanded through proliferation, the large sizes exclusively arose from activation. Simulations where homeostatic proliferation contributed more to pVL than activation, produced pVL that was less variable over time and exhibited fewer viral blips. While homeostatic proliferation adds to the latent reservoir, activation can both add and remove latent cells. Latent activation can produce large clones, where these may have been seeded much earlier than when first sampled. Elimination of the reservoir is complicated by expanding clones whose dynamic differ considerably to that of the entire reservoir.
Subject(s)
HIV Infections/virology , Latent Infection/virology , Models, Theoretical , Virus Latency/physiology , Cell Proliferation/physiology , Clone Cells/virology , Humans , Viremia/virology , Virus Replication/physiologyABSTRACT
Cytomegalovirus (CMV) infection has a major impact on the T-cell pool, which is thought to be associated with ageing of the immune system. The effect on the T-cell pool has been interpreted as an effect of CMV on non-CMV specific T-cells. However, it remains unclear whether the effect of CMV could simply be explained by the presence of large, immunodominant, CMV-specific memory CD8+ T-cell populations. These have been suggested to establish through gradual accumulation of long-lived cells. However, little is known about their maintenance. We investigated the effect of CMV infection on T-cell dynamics in healthy older adults, and aimed to unravel the mechanisms of maintenance of large numbers of CMV-specific CD8+ T-cells. We studied the expression of senescence, proliferation, and apoptosis markers and quantified the in vivo dynamics of CMV-specific and other memory T-cell populations using in vivo deuterium labelling. Increased expression of late-stage differentiation markers by CD8+ T-cells of CMV+ versus CMV- individuals was not solely explained by the presence of large, immunodominant CMV-specific CD8+ T-cell populations. The lifespans of circulating CMV-specific CD8+ T-cells did not differ significantly from those of bulk memory CD8+ T-cells, and the lifespans of bulk memory CD8+ T-cells did not differ significantly between CMV- and CMV+ individuals. Memory CD4+ T-cells of CMV+ individuals showed increased expression of late-stage differentiation markers and decreased Ki-67 expression. Overall, the expression of senescence markers on T-cell populations correlated positively with their expected in vivo lifespan. Together, this work suggests that i) large, immunodominant CMV-specific CD8+ T-cell populations do not explain the phenotypical differences between CMV+ and CMV- individuals, ii) CMV infection hardly affects the dynamics of the T-cell pool, and iii) large numbers of CMV-specific CD8+ T-cells are not due to longer lifespans of these cells.
Subject(s)
CD4-Positive T-Lymphocytes/immunology , CD8-Positive T-Lymphocytes/immunology , Cytomegalovirus Infections/immunology , Immunologic Memory/immunology , Latent Infection/immunology , Aged , Cytomegalovirus Infections/virology , Female , Humans , Latent Infection/virology , Male , Middle AgedABSTRACT
Cytomegalovirus (CMV) reactivations represent a significant morbidity and mortality problem in transplant patients. Reliable and rapid measurement of CMV viral load is a key issue for optimal patient management. We report here the evaluation of NeuMoDx™ (Qiagen) in a routine hospital setting (University Hospitals of Marseille, France) in comparison with our classical reference technique R-GENE. During one month, 719 CMV viral loads from 507 patients were measured in parallel in both techniques. Using the ROC (receiver operating characteristic) curve and our biological experience we suggest that values <52 IU/mL (geometric mean) correspond to negative samples, values >140 IU/mL (Fowlkes-Mallows index) correspond to quantifiable positive results and values ranging from 52 to 140 IU/mL represent non-quantifiable positive results. Follow-up of 15 transplant patients who developed CMV reactivation during the study showed that NeuMoDx™ provided higher viral load measurement during the first two weeks of follow-up for three patients. These important intra-individual variations resulted in a significant median increase considering the whole data set (6.7 points of difference expressed as a percentage of the initial viral load). However, no difference between the two techniques was noticeable after two weeks of treatment. Subsequent to this first study we conclude that NeuMoDx™, used with optimized logistics and an adapted threshold, allows a rapid CMV viral load measurement and that its use does not lead to any difference in patient management compared to the reference technique R-GENE®.
Subject(s)
Automation, Laboratory/standards , Cytomegalovirus Infections/virology , Cytomegalovirus/genetics , DNA, Viral/genetics , Transplant Recipients/statistics & numerical data , Viral Load/instrumentation , Automation, Laboratory/instrumentation , Automation, Laboratory/methods , Cytomegalovirus/isolation & purification , Cytomegalovirus Infections/blood , Cytomegalovirus Infections/diagnosis , Feedback , France , Humans , Laboratories, Clinical , Latent Infection/virology , Prospective Studies , Viral Load/methods , Viral Load/statistics & numerical dataABSTRACT
In stark contrast to the rapid development of vaccines against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), an effective human immunodeficiency virus (HIV) vaccine is still lacking. Furthermore, despite virologic suppression and CD4 T-cell count normalization with antiretroviral therapy (ART), people living with HIV (PLWH) still exhibit increased morbidity and mortality compared to the general population. Such differences in health outcomes are related to higher risk behaviors, but also to HIV-related immune activation and viral coinfections. Among these coinfections, cytomegalovirus (CMV) latent infection is a well-known inducer of long-term immune dysregulation. Cytomegalovirus contributes to the persistent immune activation in PLWH receiving ART by directly skewing immune response toward itself, and by increasing immune activation through modification of the gut microbiota and microbial translocation. In addition, through induction of immunosenescence, CMV has been associated with a decreased response to infections and vaccines. This review provides a comprehensive overview of the influence of CMV on the immune system, the mechanisms underlying a reduced response to vaccines, and discuss new therapeutic advances targeting CMV that could be used to improve vaccine response in PLWH.