RESUMEN

AIMS: As the interactions of alcohol and HIV/SIV infection and their impact on liver metabolic homeostasis remain to be fully elucidated, this study aimed to determine alcohol-mediated hepatic adaptations of metabolic pathways in SIV/ART-treated female rhesus macaques fed a nutritionally balanced diet. METHODS: Macaques were administered chronic binge alcohol (CBA; 13-14 g ethanol/kg/week for 14.5 months; n = 7) or vehicle (VEH; n = 8) for 14.5 months. Livers were excised following an overnight fast. Gene and protein expression, enzymatic activity, and lipid content were determined using frozen tissue and histological staining was performed using paraffin-embedded tissue. RESULTS: CBA/SIV macaques showed increased hepatic protein expression of electron transport Complex III and increased gene expression of glycolytic (phosphofructokinase and aldolase) and gluconeogenic (pyruvate carboxylase) enzymes and of genes involved in lipid turnover homeostasis (perilipin 1, peroxisome proliferator-activated receptor gamma, carbohydrate responsive binding protein, and acetyl-CoA carboxylase B) as compared to that of livers from the VEH/SIV group. Plasma triglyceride concentration had a significant positive association with liver triglyceride content in the CBA/SIV group. CONCLUSIONS: These results reflect CBA-associated alterations in expression of proteins and genes involved in glucose and lipid metabolism homeostasis without significant evidence of steatosis or dysglycemia. Whether these changes predispose to greater liver pathology upon consumption of a high fat/high sugar diet that is more aligned with dietary intake of PWH and/or exposure to additional environmental factors warrants further investigation.

Asunto(s)

Consumo Excesivo de Bebidas Alcohólicas , Hígado , Macaca mulatta , Síndrome de Inmunodeficiencia Adquirida del Simio , Animales , Femenino , Síndrome de Inmunodeficiencia Adquirida del Simio/metabolismo , Hígado/metabolismo , Hígado/efectos de los fármacos , Consumo Excesivo de Bebidas Alcohólicas/metabolismo , Adaptación Fisiológica/efectos de los fármacos , Etanol/farmacología , Metabolismo de los Lípidos/efectos de los fármacos

RESUMEN

Simian immunodeficiency virus (SIV) vaccines based upon 68-1 Rhesus Cytomegalovirus (RhCMV) vectors show remarkable protection against pathogenic SIVmac239 challenge. Across multiple independent rhesus macaque (RM) challenge studies, nearly 60% of vaccinated RM show early, complete arrest of SIVmac239 replication after effective challenge, whereas the remainder show progressive infection similar to controls. Here, we performed viral sequencing to determine whether the failure to control viral replication in non-protected RMs is associated with the acquisition of viral escape mutations. While low level viral mutations accumulated in all animals by 28 days-post-challenge, which is after the establishment of viral control in protected animals, the dominant circulating virus in virtually all unprotected RMs was nearly identical to the challenge stock, and there was no difference in mutation patterns between this cohort and unvaccinated controls. These data definitively demonstrate that viral mutation does not explain lack of viral control in RMs not protected by RhCMV/SIV vaccination. We further demonstrate that during chronic infection RhCMV/SIV vaccinated RMs do not acquire escape mutation in epitopes targeted by RhCMV/SIV, but instead display mutation in canonical MHC-Ia epitopes similar to unvaccinated RMs. This suggests that after the initial failure of viral control, unconventional T cell responses induced by 68-1 RhCMV/SIV vaccination do not exert strong selective pressure on systemically replicating SIV.

Asunto(s)

Macaca mulatta , Mutación , Vacunas contra el SIDAS , Síndrome de Inmunodeficiencia Adquirida del Simio , Virus de la Inmunodeficiencia de los Simios , Animales , Virus de la Inmunodeficiencia de los Simios/inmunología , Virus de la Inmunodeficiencia de los Simios/genética , Síndrome de Inmunodeficiencia Adquirida del Simio/inmunología , Síndrome de Inmunodeficiencia Adquirida del Simio/virología , Síndrome de Inmunodeficiencia Adquirida del Simio/prevención & control , Vacunas contra el SIDAS/inmunología , Vacunas contra el SIDAS/genética , Citomegalovirus/inmunología , Citomegalovirus/genética , Replicación Viral/inmunología , Vacunación , Evasión Inmune/genética

RESUMEN

A stripped-down HIV genome can interfere with normal virus replication.

Asunto(s)

Partículas Similares a Virus Artificiales , Infecciones por VIH , Interferencia Viral , Replicación Viral , Animales , Humanos , Fármacos Anti-VIH/uso terapéutico , Genoma Viral , Infecciones por VIH/terapia , Infecciones por VIH/virología , VIH-1/genética , VIH-1/fisiología , Macaca mulatta , Síndrome de Inmunodeficiencia Adquirida del Simio/virología , Virus de la Inmunodeficiencia de los Simios/genética

RESUMEN

Interferon-lambda receptor 1 (IFNLR1) is the key to interferon-lambda's biological activities. Rhesus macaques (Macaca mulatta) are supposedly more suitable for translational studies on interferon lambda-associated human diseases, yet little is known about their IFNLR1 (mmuIFNLR1). In this study, we cloned the coding sequence of mmuIFNLR1, examined its variants, and determined the distribution of mmuIFNLR1 mRNA and immunoreactivity in the buccal mucosa and arm skin of normal and immunodeficiency virus (SHIV/SIV) infected rhesus macaques. It was found that mmuIFNLR1 has 93.1% amino acid sequence identity to that of humans; all the amino acid residues of mmuIFNLR1 signal peptide, transmembrane region, PxxLxF motif and those essential for ligand binding are identical to that of humans; 6 variants of mmuIFNLR1, including the ones corresponding to that of humans were detected; IFNLR1 immunoreactivity was localized in primarily the epithelia of buccal mucosa and arm skin; SHIV/SIV infection could affect the levels of mmuIFNLR1 mRNA and immunoreactivity. These data expanded our knowledge on mmuIFNLR1 and provided a scientific basis for rational use of rhesus macaques in studies of IFN-λ associated human diseases like AIDS. Future studies testing IFNLR1-targeting therapeutics in rhesus macaques were warranted.

Asunto(s)

Macaca mulatta , Mucosa Bucal , Síndrome de Inmunodeficiencia Adquirida del Simio , Virus de la Inmunodeficiencia de los Simios , Piel , Animales , Mucosa Bucal/inmunología , Mucosa Bucal/virología , Piel/virología , Piel/inmunología , Piel/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 , Humanos , Secuencia de Aminoácidos , Receptores de Interferón/genética , Receptores de Interferón/metabolismo , Clonación Molecular

RESUMEN

Chronic immune activation promotes tuberculosis (TB) reactivation in the macaque Mycobacterium tuberculosis (M. tuberculosis)/SIV coinfection model. Initiating combinatorial antiretroviral therapy (cART) early lowers the risk of TB reactivation, but immune activation persists. Studies of host-directed therapeutics (HDTs) that mitigate immune activation are, therefore, required. Indoleamine 2,3, dioxygenase (IDO), a potent immunosuppressor, is one of the most abundantly induced proteins in NHP and human TB granulomas. Inhibition of IDO improves immune responses in the lung, leading to better control of TB, including adjunctive to TB chemotherapy. The IDO inhibitor D-1 methyl tryptophan (D1MT) is, therefore, a bona fide TB HDT candidate. Since HDTs against TB are likely to be deployed in an HIV coinfection setting, we studied the effect of IDO inhibition in M. tuberculosis/SIV coinfection, adjunctive to cART. D1MT is safe in this setting, does not interfere with viral suppression, and improves the quality of CD4+ and CD8+ T cell responses, including reconstitution, activation and M. tuberculosis-specific cytokine production, and access of CD8+ T cells to the lung granulomas; it reduces granuloma size and necrosis, type I IFN expression, and the recruitment of inflammatory IDO+ interstitial macrophages (IMs). Thus, trials evaluating the potential of IDO inhibition as HDT in the setting of cART in M. tuberculosis/HIV coinfected individuals are warranted.

Asunto(s)

Coinfección , Indolamina-Pirrol 2,3,-Dioxigenasa , Macaca mulatta , Mycobacterium tuberculosis , Síndrome de Inmunodeficiencia Adquirida del Simio , Triptófano , Indolamina-Pirrol 2,3,-Dioxigenasa/antagonistas & inhibidores , Indolamina-Pirrol 2,3,-Dioxigenasa/metabolismo , Animales , Síndrome de Inmunodeficiencia Adquirida del Simio/inmunología , Síndrome de Inmunodeficiencia Adquirida del Simio/tratamiento farmacológico , Coinfección/tratamiento farmacológico , Coinfección/inmunología , Triptófano/metabolismo , Triptófano/análogos & derivados , Tuberculosis/inmunología , Tuberculosis/tratamiento farmacológico , Virus de la Inmunodeficiencia de los Simios/inmunología , Modelos Animales de Enfermedad , Linfocitos T CD8-positivos/inmunología , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/inmunología , Infecciones por VIH/complicaciones , Antirretrovirales/uso terapéutico , Antirretrovirales/farmacología , Masculino , Pulmón/inmunología , Pulmón/patología , Humanos , Linfocitos T CD4-Positivos/inmunología

RESUMEN

Persistence of the rebound-competent viral reservoir (RCVR) within the CD4+ T cell compartment of people living with HIV remains a major barrier to HIV cure. Here, we determined the effects of the pan-lymphocyte-depleting monoclonal antibody (mAb) alemtuzumab on the RCVR in SIVmac239-infected rhesus macaques (RM) receiving antiretroviral therapy (ART). Alemtuzumab administered during chronic ART or at the time of ART initiation induced >95% depletion of circulating CD4+ T cells in peripheral blood and substantial CD4+ T cell depletion in lymph nodes. However, treatment was followed by proliferation and reconstitution of CD4+ T cells in blood, and despite ongoing ART, levels of cell-associated SIV DNA in blood and lymphoid tissues were not substantially different between alemtuzumab-treated and control RM after immune cell reconstitution, irrespective of the time of alemtuzumab treatment. Upon ART cessation, 19 of 22 alemtuzumab-treated RM and 13 of 13 controls rebounded with no difference in the time to rebound between treatment groups. Time to rebound and reactivation rate was associated with plasma viral loads (pVLs) at time of ART initiation, suggesting lymphocyte depletion had no durable impact on the RCVR. However, 3 alemtuzumab-treated RM that had lowest levels of pre-ART viremia, failed to rebound after ART withdrawal, in contrast to controls with similar levels of SIV replication. These observations suggest that alemtuzumab therapy has little to no ability to reduce well-established RCVRs but may facilitate RCVR destabilization when pre-ART virus levels are particularly low.

Asunto(s)

Alemtuzumab , Depleción Linfocítica , Macaca mulatta , Síndrome de Inmunodeficiencia Adquirida del Simio , Virus de la Inmunodeficiencia de los Simios , Carga Viral , Animales , Virus de la Inmunodeficiencia de los Simios/efectos de los fármacos , Virus de la Inmunodeficiencia de los Simios/inmunología , Síndrome de Inmunodeficiencia Adquirida del Simio/tratamiento farmacológico , Síndrome de Inmunodeficiencia Adquirida del Simio/inmunología , Síndrome de Inmunodeficiencia Adquirida del Simio/virología , Alemtuzumab/farmacología , Depleción Linfocítica/métodos , Carga Viral/efectos de los fármacos , Linfocitos T CD4-Positivos/inmunología , Linfocitos T CD4-Positivos/virología , Linfocitos T CD4-Positivos/efectos de los fármacos

RESUMEN

Anti-HIV-1 broadly neutralizing antibodies (bNAbs) have the dual potential of mediating virus neutralization and antiviral effector functions through their Fab and Fc domains, respectively. So far, bNAbs with enhanced Fc effector functions in vitro have only been tested in NHPs during chronic simian-HIV (SHIV) infection. Here, we investigate the effects of administering in acute SHIVAD8-EO infection either wild-type (WT) bNAbs or bNAbs carrying the S239D/I332E/A330L (DEL) mutation, which increases binding to FcγRs. Emergence of virus in plasma and lymph nodes (LNs) was delayed by bNAb treatment and occurred earlier in monkeys given DEL bNAbs than in those given WT bNAbs, consistent with faster clearance of DEL bNAbs from plasma. DEL bNAb-treated monkeys had higher levels of circulating virus-specific IFNγ single-producing CD8+ CD69+ T cells than the other groups. In LNs, WT bNAbs were evenly distributed between follicular and extrafollicular areas, but DEL bNAbs predominated in the latter. At week 8 post-challenge, LN monocytes and NK cells from DEL bNAb-treated monkeys upregulated proinflammatory signaling pathways and LN T cells downregulated TNF signaling via NF-κB. Overall, bNAbs with increased affinity to FcγRs shape innate and adaptive cellular immunity, which may be important to consider in future strategies of passive bNAb therapy.

Asunto(s)

Anticuerpos Neutralizantes , Anticuerpos Anti-VIH , VIH-1 , Macaca mulatta , Receptores de IgG , Síndrome de Inmunodeficiencia Adquirida del Simio , Virus de la Inmunodeficiencia de los Simios , Animales , Receptores de IgG/inmunología , Receptores de IgG/metabolismo , Síndrome de Inmunodeficiencia Adquirida del Simio/inmunología , Síndrome de Inmunodeficiencia Adquirida del Simio/virología , VIH-1/inmunología , Virus de la Inmunodeficiencia de los Simios/inmunología , Anticuerpos Neutralizantes/inmunología , Anticuerpos Anti-VIH/inmunología , Anticuerpos Monoclonales/inmunología , Ganglios Linfáticos/inmunología , Linfocitos T CD8-positivos/inmunología , Afinidad de Anticuerpos/inmunología , FN-kappa B/metabolismo , FN-kappa B/inmunología , Humanos , Infecciones por VIH/inmunología , Infecciones por VIH/virología , Células Asesinas Naturales/inmunología , Anticuerpos ampliamente neutralizantes/inmunología

RESUMEN

HIV-induced persistent immune activation is a key mediator of inflammatory comorbidities such as cardiovascular disease (CVD) and neurocognitive disorders. While a preponderance of data indicate that gut barrier disruption and microbial translocation are drivers of chronic immune activation, the molecular mechanisms of this persistent inflammatory state remain poorly understood. Here, utilizing the nonhuman primate model of Human Immunodeficiency Virus (HIV) infection with suppressive antiretroviral therapy (ART), we investigated activation of inflammasome pathways and their association with intestinal epithelial barrier disruption (IEBD). Longitudinal blood samples obtained from rhesus macaques with chronic SIV infection and long-term suppressive ART were evaluated for IEBD biomarkers, inflammasome activation (IL-1ß and IL-18), inflammatory cytokines, and triglyceride (TG) levels. Activated monocyte subpopulations and glycolytic potential were investigated in peripheral blood mononuclear cells (PBMCs). During the chronic phase of treated SIV infection, elevated levels of plasma IL-1ß and IL-18 were observed following the hallmark increase in IEBD biomarkers, intestinal fatty acid-binding protein (IFABP) and LPS-binding protein (LBP). Further, significant correlations of plasma IFABP levels with IL-1ß and IL-18 were observed between 10 and 12 months of ART. Higher levels of sCD14, IL-6, and GM-CSF, among other inflammatory mediators, were also observed only during the long-term SIV + ART phase along with a trend of increase in the frequencies of activated CD14+CD16+ intermediate monocyte subpopulations. Lastly, we found elevated levels of blood TG and higher glycolytic capacity in PBMCs of chronic SIV-infected macaques with long-term ART. The increase in circulating IL-18 and IL-1ß following IEBD and their significant positive correlation with IFABP suggest a connection between gut barrier disruption and inflammasome activation during chronic SIV infection, despite viral suppression with ART. Additionally, the increase in markers of monocyte activation, along with elevated TG and enhanced glycolytic pathway activity, indicates metabolic remodeling that could fuel metabolic syndrome. Further research is needed to understand the mechanisms by which gut dysfunction and inflammasome activation contribute to HIV-associated metabolic complications, enabling targeted interventions in people with HIV.

Asunto(s)

Interleucina-18 , Interleucina-1beta , Mucosa Intestinal , Macaca mulatta , Monocitos , Síndrome de Inmunodeficiencia Adquirida del Simio , Virus de la Inmunodeficiencia de los Simios , Animales , Síndrome de Inmunodeficiencia Adquirida del Simio/inmunología , Síndrome de Inmunodeficiencia Adquirida del Simio/sangre , Síndrome de Inmunodeficiencia Adquirida del Simio/tratamiento farmacológico , Interleucina-18/sangre , Interleucina-18/metabolismo , Monocitos/metabolismo , Monocitos/inmunología , Interleucina-1beta/sangre , Interleucina-1beta/metabolismo , Mucosa Intestinal/metabolismo , Antirretrovirales/uso terapéutico , Inflamasomas/metabolismo , Biomarcadores/sangre , Masculino , Leucocitos Mononucleares/metabolismo , Enfermedad Crónica

RESUMEN

While the benefits of early antiretroviral therapy (ART) initiation in perinatally infected infants are well documented, early initiation is not always possible in postnatal pediatric HIV infections. The timing of ART initiation is likely to affect the size of the latent viral reservoir established, as well as the development of adaptive immune responses, such as the generation of neutralizing antibody responses against the virus. How these parameters impact the ability of infants to control viremia and the time to viral rebound after ART interruption is unclear and has never been modeled in infants. To investigate this question we used an infant nonhuman primate Simian/Human Immunodeficiency Virus (SHIV) infection model. Infant Rhesus macaques (RMs) were orally challenged with SHIV.C.CH505 375H dCT and either given ART at 4-7 days post-infection (early ART condition), at 2 weeks post-infection (intermediate ART condition), or at 8 weeks post-infection (late ART condition). These infants were then monitored for up to 60 months post-infection with serial viral load and immune measurements. To gain insight into early after analytic treatment interruption (ATI), we constructed mathematical models to investigate the effect of time of ART initiation in delaying viral rebound when treatment is interrupted, focusing on the relative contributions of latent reservoir size and autologous virus neutralizing antibody responses. We developed a stochastic mathematical model to investigate the joint effect of latent reservoir size, the autologous neutralizing antibody potency, and CD4+ T cell levels on the time to viral rebound for RMs rebounding up to 60 days post-ATI. We find that the latent reservoir size is an important determinant in explaining time to viral rebound in infant macaques by affecting the growth rate of the virus. The presence of neutralizing antibodies can also delay rebound, but we find this effect for high potency antibody responses only. Finally, we discuss the therapeutic implications of our findings.

Asunto(s)

Anticuerpos Neutralizantes , Macaca mulatta , Síndrome de Inmunodeficiencia Adquirida del Simio , Virus de la Inmunodeficiencia de los Simios , Carga Viral , Animales , Síndrome de Inmunodeficiencia Adquirida del Simio/inmunología , Síndrome de Inmunodeficiencia Adquirida del Simio/tratamiento farmacológico , Anticuerpos Neutralizantes/inmunología , Anticuerpos Neutralizantes/uso terapéutico , Virus de la Inmunodeficiencia de los Simios/inmunología , Carga Viral/inmunología , Viremia/inmunología , Viremia/tratamiento farmacológico , Modelos Animales de Enfermedad , Antirretrovirales/uso terapéutico , Animales Recién Nacidos , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/inmunología

RESUMEN

Perivascular macrophages (PVMs) and, to a lesser degree, microglia are targets and reservoirs of HIV and simian immunodeficiency virus (SIV) in the brain. Previously, we demonstrated that colony-stimulating factor 1 receptor (CSF1R) in PVMs was upregulated and activated in chronically SIV-infected rhesus macaques with encephalitis, correlating with SIV infection of PVMs. Herein, we investigated the role of CSF1R in the brain during acute SIV infection using BLZ945, a brain-penetrant CSF1R kinase inhibitor. Apart from three uninfected historic controls, nine Indian rhesus macaques were infected acutely with SIVmac251 and divided into three groups (n = 3 each): an untreated control and two groups treated for 20-30 days with low- (10 mg/kg/day) or high- (30 mg/kg/day) dose BLZ945. With the high-dose BLZ945 treatment, there was a significant reduction in cells expressing CD163 and CD206 across all four brain areas examined, compared with the low-dose treatment and control groups. In 9 of 11 tested regions, tissue viral DNA (vDNA) loads were reduced by 95%-99% following at least one of the two doses, and even to undetectable levels in some instances. Decreased numbers of CD163+ and CD206+ cells correlated significantly with lower levels of vDNA in all four corresponding brain areas. In contrast, BLZ945 treatment did not significantly affect the number of microglia. Our results indicate that doses as low as 10 mg/kg/day of BLZ945 are sufficient to reduce the tissue vDNA loads in the brain with no apparent adverse effect. This study provides evidence that infected PVMs are highly sensitive to CSF1R inhibition, opening new possibilities to achieve viral clearance.

Asunto(s)

Encéfalo , Macaca mulatta , Macrófagos , Síndrome de Inmunodeficiencia Adquirida del Simio , Virus de la Inmunodeficiencia de los Simios , Animales , Síndrome de Inmunodeficiencia Adquirida del Simio/tratamiento farmacológico , Síndrome de Inmunodeficiencia Adquirida del Simio/inmunología , Virus de la Inmunodeficiencia de los Simios/efectos de los fármacos , Macrófagos/metabolismo , Macrófagos/efectos de los fármacos , Encéfalo/metabolismo , Encéfalo/efectos de los fármacos , Encéfalo/virología , Receptores de Factor Estimulante de Colonias de Granulocitos y Macrófagos/antagonistas & inhibidores , Receptores de Factor Estimulante de Colonias de Granulocitos y Macrófagos/metabolismo , Carga Viral/efectos de los fármacos , Pirimidinas/farmacología , Pirimidinas/uso terapéutico , Antígenos CD/metabolismo , Masculino , Microglía/efectos de los fármacos , Microglía/metabolismo , Microglía/virología , Antígenos de Diferenciación Mielomonocítica/metabolismo , Receptores de Superficie Celular/metabolismo , Anisoles

RESUMEN

The effects of immunodeficiency associated with chronic HIV infection on COVID-19 disease and viral persistence have not been directly addressed in a controlled setting. In this pilot study, we exposed two pigtail macaques (PTMs) chronically infected with SIVmac239, exhibiting from very low to no CD4 T cells across all compartments, to SARS-CoV-2. We monitored the disease progression, viral replication, and evolution, and compared these outcomes with SIV-naïve PTMs infected with SARS-CoV-2. No overt signs of COVID-19 disease were observed in either animal, and the SARS-CoV-2 viral kinetics and evolution in the SIVmac239 PTMs were indistinguishable from those in the SIV-naïve PTMs in all sampled mucosal sites. However, the single-cell RNA sequencing of bronchoalveolar lavage cells revealed an infiltration of functionally inert monocytes after SARS-CoV-2 infection. Critically, neither of the SIV-infected PTMs mounted detectable anti-SARS-CoV-2 T-cell responses nor anti-SARS-CoV-2 binding or neutralizing antibodies. Thus, HIV-induced immunodeficiency alone may not be sufficient to drive the emergence of novel viral variants but may remove the ability of infected individuals to mount adaptive immune responses against SARS-CoV-2.

Asunto(s)

COVID-19 , Coinfección , Modelos Animales de Enfermedad , SARS-CoV-2 , Síndrome de Inmunodeficiencia Adquirida del Simio , Virus de la Inmunodeficiencia de los Simios , Animales , Virus de la Inmunodeficiencia de los Simios/inmunología , COVID-19/inmunología , COVID-19/virología , Síndrome de Inmunodeficiencia Adquirida del Simio/inmunología , Síndrome de Inmunodeficiencia Adquirida del Simio/virología , SARS-CoV-2/inmunología , Coinfección/inmunología , Coinfección/virología , Replicación Viral , Macaca nemestrina , Proyectos Piloto , Anticuerpos Antivirales/inmunología , Anticuerpos Antivirales/sangre , Carga Viral , Linfocitos T CD4-Positivos/inmunología , Anticuerpos Neutralizantes/inmunología , Anticuerpos Neutralizantes/sangre

RESUMEN

We recently demonstrated that Simian-HIV (SHIV)-infected neonate rhesus macaques (RMs) generated heterologous HIV-1 neutralizing antibodies (NAbs) with broadly-NAb (bNAb) characteristics at a higher frequency compared with their corresponding dam. Here, we characterized genetic diversity in Env sequences from four neonate or adult/dam RM pairs: in two pairs, neonate and dam RMs made heterologous HIV-1 NAbs; in one pair, neither the neonate nor the dam made heterologous HIV-1 NAbs; and in another pair, only the neonate made heterologous HIV-1 NAbs. Phylogenetic and sequence diversity analyses of longitudinal Envs revealed that a higher genetic diversity, within the host and away from the infecting SHIV strain, was correlated with heterologous HIV-1 NAb development. We identified 22 Env variable sites, of which 9 were associated with heterologous HIV-1 NAb development; 3/9 sites had mutations previously linked to HIV-1 Env bNAb development. These data suggested that viral diversity drives heterologous HIV-1 NAb development, and the faster accumulation of viral diversity in neonate RMs may be a potential mechanism underlying bNAb induction in pediatric populations. Moreover, these data may inform candidate Env immunogens to guide precursor B cells to bNAb status via vaccination by the Env-based selection of bNAb lineage members with the appropriate mutations associated with neutralization breadth.

Asunto(s)

Anticuerpos Neutralizantes , Evolución Molecular , VIH-1 , Macaca mulatta , Filogenia , Síndrome de Inmunodeficiencia Adquirida del Simio , Virus de la Inmunodeficiencia de los Simios , Animales , Virus de la Inmunodeficiencia de los Simios/genética , Virus de la Inmunodeficiencia de los Simios/inmunología , Síndrome de Inmunodeficiencia Adquirida del Simio/virología , VIH-1/genética , VIH-1/inmunología , VIH-1/clasificación , Anticuerpos Neutralizantes/inmunología , Anticuerpos Neutralizantes/sangre , Variación Genética , Animales Recién Nacidos , Anticuerpos Anti-VIH/inmunología , Anticuerpos Anti-VIH/sangre , Proteínas del Envoltorio Viral/genética , Proteínas del Envoltorio Viral/inmunología , Infecciones por VIH/virología

RESUMEN

Human immunodeficiency virus (HIV) and malaria, caused by infection with Plasmodium spp., are endemic in similar geographical locations. As a result, there is high potential for HIV/Plasmodium co-infection, which increases the pathology of both diseases. However, the immunological mechanisms underlying the exacerbated disease pathology observed in co-infected individuals are poorly understood. Moreover, there is limited data available on the impact of Plasmodium co-infection on antiretroviral (ART)-treated HIV infection. Here, we used the rhesus macaque (RM) model to conduct a pilot study to establish a model of Plasmodium fragile co-infection during ART-treated simian immunodeficiency virus (SIV) infection, and to begin to characterize the immunopathogenic effect of co-infection in the context of ART. We observed that P. fragile co-infection resulted in parasitemia and anemia, as well as persistently detectable viral loads (VLs) and decreased absolute CD4+ T-cell counts despite daily ART treatment. Notably, P. fragile co-infection was associated with increased levels of inflammatory cytokines, including monocyte chemoattractant protein 1 (MCP-1). P. fragile co-infection was also associated with increased levels of neutrophil elastase, a plasma marker of neutrophil extracellular trap (NET) formation, but significant decreases in markers of neutrophil degranulation, potentially indicating a shift in the neutrophil functionality during co-infection. Finally, we characterized the levels of plasma markers of gastrointestinal (GI) barrier permeability and microbial translocation and observed significant correlations between indicators of GI dysfunction, clinical markers of SIV and Plasmodium infection, and neutrophil frequency and function. Taken together, these pilot data verify the utility of using the RM model to examine ART-treated SIV/P. fragile co-infection, and indicate that neutrophil-driven inflammation and GI dysfunction may underlie heightened SIV/P. fragile co-infection pathogenesis.

Asunto(s)

Coinfección , Inflamación , Macaca mulatta , Malaria , Neutrófilos , Plasmodium , Síndrome de Inmunodeficiencia Adquirida del Simio , Virus de la Inmunodeficiencia de los Simios , Animales , Coinfección/tratamiento farmacológico , Coinfección/parasitología , Coinfección/virología , Malaria/tratamiento farmacológico , Malaria/inmunología , Malaria/complicaciones , Síndrome de Inmunodeficiencia Adquirida del Simio/tratamiento farmacológico , Síndrome de Inmunodeficiencia Adquirida del Simio/inmunología , Síndrome de Inmunodeficiencia Adquirida del Simio/complicaciones , Proyectos Piloto , Neutrófilos/inmunología , Antirretrovirales/uso terapéutico , Carga Viral , Biomarcadores/sangre , Citocinas/sangre , Modelos Animales de Enfermedad , Infecciones por VIH/complicaciones , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/inmunología

RESUMEN

Viral infection generally induces polyclonal neutralizing antibody responses. However, how many lineages of antibody responses can fully represent the neutralization activities in sera has not been well studied. Using the newly designed stable HIV-1 Env trimer as hook, we isolated two distinct broadly neutralizing antibodies (bnAbs) from Chinese rhesus macaques infected with SHIV1157ipd3N4 for 5 years. One lineage of neutralizing antibodies (JT15 and JT16) targeted the V2-apex in the Env trimers, similar to the J038 lineage bnAbs identified in our previous study. The other lineage neutralizing antibody (JT18) targeted the V3 crown region in the Env, which strongly competed with human 447-52D. Each lineage antibody neutralized a different set of viruses. Interestingly, when the two neutralizing antibodies from different lineages isolated from the same macaque were combined, the mixture had a neutralization breath very similar to that from the cognate sera. Our study demonstrated that a minimum of two different neutralizing antibodies can fully recapitulate the serum neutralization breadth. This observation can have important implications in AIDS vaccine design.

Asunto(s)

Anticuerpos Neutralizantes , Anticuerpos Anti-VIH , VIH-1 , Macaca mulatta , Síndrome de Inmunodeficiencia Adquirida del Simio , Macaca mulatta/inmunología , Animales , VIH-1/inmunología , Anticuerpos Anti-VIH/inmunología , Anticuerpos Anti-VIH/sangre , Anticuerpos Neutralizantes/inmunología , Anticuerpos Neutralizantes/sangre , Humanos , Síndrome de Inmunodeficiencia Adquirida del Simio/inmunología , Síndrome de Inmunodeficiencia Adquirida del Simio/sangre , Síndrome de Inmunodeficiencia Adquirida del Simio/virología , Infecciones por VIH/inmunología , Infecciones por VIH/virología , Infecciones por VIH/sangre , Virus de la Inmunodeficiencia de los Simios/inmunología , Productos del Gen env del Virus de la Inmunodeficiencia Humana/inmunología , Pruebas de Neutralización

RESUMEN

While simian immunodeficiency virus (SIV) infection is non-pathogenic in naturally infected African nonhuman primate hosts, experimental or accidental infection in rhesus macaques often leads to AIDS. Baboons, widely distributed throughout Africa, do not naturally harbor SIV, and experimental infection of baboons with SIVmac results in transient low-level viral replication. Elucidation of mechanisms of natural immunity in baboons could uncover new targets of antiviral intervention. We tested the hypothesis that an SIVmac adapted to replicate in baboon primary cells will gain the capacity to establish chronic infections in vivo. Here, we generated SIVmac variants in baboon cells through serial passage in PBMC from different donors (SIVbn-PBMC s1), in PBMC from the same donors (SIVbn-PBMC s2), or in isolated CD4 cells from the same donors used for series 2 (SIVbn-CD4). While SIVbn-PBMC s1 and SIVbn-CD4 demonstrated increased replication capacity, SIVbn-PBMC s2 did not. Pharmacological blockade of CCR5 revealed SIVbn-PBMC s1 could more efficiently use available CCR5 than SIVmac, a trait we hypothesize arose to circumvent receptor occupation by chemokines. Sequencing analysis showed that all three viruses accumulated different types of mutations, and that more non-synonymous mutations became fixed in SIVbn-PBMC s1 than SIVbn-PBMC s2 and SIVbn-CD4, supporting the notion of stronger fitness pressure in PBMC from different genetic backgrounds. Testing the individual contribution of several newly fixed SIV mutations suggested that is the additive effect of these mutations in SIVbn-PBMC s1 that contributed to its enhanced fitness, as recombinant single mutant viruses showed no difference in replication capacity over the parental SIVmac239 strain. The replicative capacity of SIVbn-PBMC passage 4 (P4) s1 was tested in vivo by infecting baboons intravenously with SIVbn-PBMC P4 s1 or SIVmac251. While animals infected with SIVmac251 showed the known pattern of transient low-level viremia, animals infected with SIVbn-PBMC P4 s1 had undetectable viremia or viral DNA in lymphoid tissue. These studies suggest that adaptation of SIV to grow in baboon primary cells results in mutations that confer increased replicative capacity in the artificial environment of cell culture but make the virus unable to avoid the restrictive factors generated by a complex multicellular organism.

Asunto(s)

Papio , Síndrome de Inmunodeficiencia Adquirida del Simio , Virus de la Inmunodeficiencia de los Simios , Replicación Viral , Animales , Virus de la Inmunodeficiencia de los Simios/genética , Virus de la Inmunodeficiencia de los Simios/fisiología , Síndrome de Inmunodeficiencia Adquirida del Simio/virología , Síndrome de Inmunodeficiencia Adquirida del Simio/inmunología , Leucocitos Mononucleares/virología , Leucocitos Mononucleares/inmunología , Receptores CCR5/metabolismo , Receptores CCR5/genética , Linfocitos T CD4-Positivos/virología , Linfocitos T CD4-Positivos/inmunología , Células Cultivadas , Pase Seriado

RESUMEN

Antibody-mediated depletion studies have demonstrated that CD8+ T cells are required for effective immune control of SIV. However, this approach is potentially confounded by several factors, including reactive CD4+ T cell proliferation, and provides no information on epitope specificity, a likely determinant of CD8+ T cell efficacy. We circumvented these limitations by selectively depleting CD8+ T cells specific for the Gag epitope CTPYDINQM (CM9) via the administration of immunotoxin-conjugated tetrameric complexes of CM9/Mamu-A*01. Immunotoxin administration effectively depleted circulating but not tissue-localized CM9-specific CD8+ T cells, akin to the bulk depletion pattern observed with antibodies directed against CD8. However, we found no evidence to indicate that circulating CM9-specific CD8+ T cells suppressed viral replication in Mamu-A*01+ rhesus macaques during acute or chronic progressive infection with a pathogenic strain of SIV. This observation extended to macaques with established infection during and after continuous antiretroviral therapy. In contrast, natural controller macaques experienced dramatic increases in plasma viremia after immunotoxin administration, highlighting the importance of CD8+ T cell-mediated immunity against CM9. Collectively, these data showed that CM9-specific CD8+ T cells were necessary but not sufficient for robust immune control of SIV in a nonhuman primate model and, more generally, validated an approach that could inform the design of next-generation vaccines against HIV-1.

Asunto(s)

Linfocitos T CD8-positivos , Inmunotoxinas , Macaca mulatta , Síndrome de Inmunodeficiencia Adquirida del Simio , Virus de la Inmunodeficiencia de los Simios , Animales , Linfocitos T CD8-positivos/inmunología , Virus de la Inmunodeficiencia de los Simios/inmunología , Síndrome de Inmunodeficiencia Adquirida del Simio/inmunología , Inmunotoxinas/inmunología , Inmunotoxinas/farmacología , Productos del Gen gag/inmunología , Replicación Viral/inmunología , Replicación Viral/efectos de los fármacos , Depleción Linfocítica/métodos

RESUMEN

Identifying immune correlates of protection is a major challenge in AIDS vaccine development. Anti-Envelope antibodies have been considered critical for protection against SIV/HIV (SHIV) acquisition. Here, we evaluated the efficacy of an SHIV vaccine against SIVmac251 challenge, where the role of antibody was excluded, as there was no cross-reactivity between SIV and SHIV envelope antibodies. After 8 low-dose intrarectal challenges with SIVmac251, 12 SHIV-vaccinated animals demonstrated efficacy, compared with 6 naive controls, suggesting protection was achieved in the absence of anti-envelope antibodies. Interestingly, CD8+ T cells (and some NK cells) were not essential for preventing viral acquisition, as none of the CD8-depleted macaques were infected by SIVmac251 challenges. Initial investigation of protective innate immunity revealed that protected animals had elevated pathways related to platelet aggregation/activation and reduced pathways related to interferon and responses to virus. Moreover, higher expression of platelet factor 4 on circulating platelet-leukocyte aggregates was associated with reduced viral acquisition. Our data highlighted the importance of innate immunity, identified mechanisms, and may provide opportunities for novel HIV vaccines or therapeutic strategy development.

Asunto(s)

Linfocitos T CD8-positivos , Inmunidad Innata , Macaca mulatta , Vacunas contra el SIDAS , Síndrome de Inmunodeficiencia Adquirida del Simio , Virus de la Inmunodeficiencia de los Simios , Animales , Síndrome de Inmunodeficiencia Adquirida del Simio/inmunología , Síndrome de Inmunodeficiencia Adquirida del Simio/prevención & control , Virus de la Inmunodeficiencia de los Simios/inmunología , Vacunas contra el SIDAS/inmunología , Inmunidad Innata/inmunología , Linfocitos T CD8-positivos/inmunología , Anticuerpos Antivirales/inmunología , Masculino , Vacunas Atenuadas/inmunología

RESUMEN

Arenaviral vaccine vectors encoding simian immunodeficiency virus (SIV) immunogens are capable of inducing efficacious humoral and cellular immune responses in nonhuman primates. Several studies have evaluated the use of immune modulators to further enhance vaccine-induced T-cell responses. The hematopoietic growth factor Flt3L drives the expansion of various bone marrow progenitor populations, and administration of Flt3L was shown to promote expansion of dendritic cell populations in spleen and blood, which are targets of arenaviral vectors. Therefore, we evaluated the potential of Flt3 signaling to enhance the immunogenicity of arenaviral vaccines encoding SIV immunogens (SIVSME543 Gag, Env, and Pol) in rhesus macaques, with a rhesus-specific engineered Flt3L-Fc fusion protein. In healthy animals, administration of Flt3L-Fc led to a 10- to 100-fold increase in type 1 dendritic cells 7 days after dosing, with no antidrug antibody (ADA) generation after repeated dosing. We observed that administration of Flt3L-Fc fusion protein 7 days before arenaviral vaccine increased the frequency and activation of innate immune cells and enhanced T-cell activation with no treatment-related adverse events. Flt3L-Fc administration induced early innate immune activation, leading to a significant enhancement in magnitude, breadth, and polyfunctionality of vaccine-induced T-cell responses. The Flt3L-Fc enhancement in vaccine immunogenicity was comparable to a combination with αCTLA-4 and supports the use of safe and effective variants of Flt3L to augment therapeutic vaccine-induced T-cell responses.IMPORTANCEInduction of a robust human immunodeficiency virus (HIV)-specific CD4+ and CD8+ T-cell response through therapeutic vaccination is considered essential for HIV cure. Arenaviral vaccine vectors encoding simian immunodeficiency virus (SIV) immunogens have demonstrated strong immunogenicity and efficacy in nonhuman primates. Here, we demonstrate that the immunogenicity of arenaviral vectors encoding SIV immunogens can be enhanced by administration of Flt3L-Fc fusion protein 7 days before vaccination. Flt3L-Fc-mediated increase in dendritic cells led to robust improvements in vaccine-induced T- and B-cell responses compared with vaccine alone, and Flt3L-Fc dosing was not associated with any treatment-related adverse events. Importantly, immune modulation by either Flt3L-Fc or αCTLA-4 led to comparable enhancement in vaccine response. These results indicate that the addition of Flt3L-Fc fusion protein before vaccine administration can significantly enhance vaccine immunogenicity. Thus, safe and effective Flt3L variants could be utilized as part of a combination therapy for HIV cure.

Asunto(s)

Células Dendríticas , Macaca mulatta , Vacunas contra el SIDAS , Virus de la Inmunodeficiencia de los Simios , Animales , Virus de la Inmunodeficiencia de los Simios/inmunología , Células Dendríticas/inmunología , Vacunas contra el SIDAS/inmunología , Síndrome de Inmunodeficiencia Adquirida del Simio/inmunología , Síndrome de Inmunodeficiencia Adquirida del Simio/prevención & control , Proteínas de la Membrana/inmunología , Proteínas de la Membrana/genética , Tirosina Quinasa 3 Similar a fms/inmunología , Tirosina Quinasa 3 Similar a fms/genética , Anticuerpos Antivirales/inmunología , Anticuerpos Antivirales/sangre , Vectores Genéticos , Inmunogenicidad Vacunal , Linfocitos T CD8-positivos/inmunología

RESUMEN

Despite antiretroviral therapy (ART), HIV-associated peripheral neuropathy remains one of the most prevalent neurologic manifestations of HIV infection. The spinal cord is an essential component of sensory pathways, but spinal cord sampling and evaluation in people with HIV has been very limited, especially in those on ART. The SIV/macaque model allows for assessment of the spinal cord at key time points throughout infection with and without ART. In this study, RNA was isolated from the spinal cord of uninfected, SIV+, and SIV + ART animals to track alterations in gene expression using global RNA-seq. Next, the SeqSeek platform was used to map changes in gene expression to specific cell types. Pathway analysis of differentially expressed genes demonstrated that highly upregulated genes in SIV-infected spinal cord aligned with interferon and viral response pathways. Additionally, this upregulated gene set significantly overlapped with those expressed in myeloid-derived cells including microglia. Downregulated genes were involved in cholesterol and collagen biosynthesis, and TGF-b regulation of extracellular matrix. In contrast, enriched pathways identified in SIV + ART animals included neurotransmitter receptors and post synaptic signaling regulators, and transmission across chemical synapses. SeqSeek analysis showed that upregulated genes were primarily expressed by neurons rather than glia. These findings indicate that pathways activated in the spinal cord of SIV + ART macaques are predominantly involved in neuronal signaling rather than proinflammatory pathways. This study provides the basis for further evaluation of mechanisms of SIV infection + ART within the spinal cord with a focus on therapeutic interventions to maintain synaptodendritic homeostasis.

Asunto(s)

Neuroglía , Neuronas , Síndrome de Inmunodeficiencia Adquirida del Simio , Médula Espinal , Animales , Síndrome de Inmunodeficiencia Adquirida del Simio/metabolismo , Síndrome de Inmunodeficiencia Adquirida del Simio/genética , Síndrome de Inmunodeficiencia Adquirida del Simio/tratamiento farmacológico , Médula Espinal/metabolismo , Médula Espinal/efectos de los fármacos , Médula Espinal/virología , Neuroglía/metabolismo , Neuroglía/efectos de los fármacos , Neuroglía/virología , Neuronas/metabolismo , Neuronas/efectos de los fármacos , Neuronas/virología , Antirretrovirales/uso terapéutico , Antirretrovirales/farmacología , Virus de la Inmunodeficiencia de los Simios/efectos de los fármacos , Macaca mulatta , Expresión Génica/efectos de los fármacos , Masculino , Regulación de la Expresión Génica/efectos de los fármacos

RESUMEN

The capacity of HIV-1 to replicate during optimal antiretroviral therapy (ART) is challenging to assess directly. To gain greater sensitivity to detect evolution on ART, we used a nonhuman primate (NHP) model providing precise control over the level of pre-ART evolution and more comprehensive analyses than are possible with clinical samples. We infected 21 rhesus macaques (RMs) with the barcoded virus SIVmac239M and initiated ART early to minimize baseline genetic diversity. RMs were treated for 285-1200 days. We used several tests of molecular evolution to compare 1352 near-full-length (nFL) SIV DNA single genome sequences from PBMCs, lymph nodes, and spleen obtained near the time of ART initiation and those present after long-term ART, none of which showed significant changes to the SIV DNA population during ART in any animal. To investigate the possibility of ongoing replication in unsampled putative tissue sanctuaries during ART, we discontinued treatment in four animals and confirmed that none of the 336 nFL SIV RNA sequences obtained from rebound plasma viremia showed evidence of evolution. The rigorous nature of our analyses reinforced the emerging consensus of a lack of appreciable ongoing replication on effective ART and validates the relevance of this NHP model for cure studies.

Asunto(s)

Antirretrovirales , Macaca mulatta , Síndrome de Inmunodeficiencia Adquirida del Simio , Virus de la Inmunodeficiencia de los Simios , Replicación Viral , Animales , Virus de la Inmunodeficiencia de los Simios/genética , Virus de la Inmunodeficiencia de los Simios/efectos de los fármacos , Virus de la Inmunodeficiencia de los Simios/fisiología , Síndrome de Inmunodeficiencia Adquirida del Simio/virología , Síndrome de Inmunodeficiencia Adquirida del Simio/tratamiento farmacológico , Replicación Viral/efectos de los fármacos , Antirretrovirales/uso terapéutico , Evolución Molecular , ARN Viral/genética , Carga Viral/efectos de los fármacos , Viremia/tratamiento farmacológico , Viremia/virología , ADN Viral/genética , Masculino