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Background: Persisting HIV reservoir viruses in resting CD4 T cells and other cellular subsets are the main barrier to cure efforts. Antiretroviral therapy (ART) intensification by early initiation has been shown to enable post-treatment viral control in some cases but the underlying mechanisms are not fully understood. We hypothesized that ART initiated during the hyperacute phase of infection before peak will affect the size, decay dynamics and landscape characteristics of HIV-1 subtype C viral reservoirs. Methods: We studied 35 women at high risk of infection from Durban, South Africa identified with hyperacute HIV infection by twice weekly testing for plasma HIV-1 RNA. Study participants included 11 who started ART at a median of 456 (297-1203) days post onset of viremia (DPOV), and 24 who started ART at a median of 1 (1-3) DPOV. We used peripheral blood mononuclear cells (PBMC) to measure total HIV-1 DNA by ddPCR and to sequence reservoir viral genomes by full length individual proviral sequencing (FLIP-seq) from onset of detection of HIV up to 1 year post treatment initiation. Results: Whereas ART in hyperacute infection blunted peak viremia compared to untreated individuals (p<0.0001), there was no difference in total HIV-1 DNA measured contemporaneously (p=0.104). There was a steady decline of total HIV DNA in early treated persons over 1 year of ART (p=0.0004), with no significant change observed in the late treated group. Total HIV-1 DNA after one year of treatment was lower in the early treated compared to the late treated group (p=0.02). Generation of 697 single viral genome sequences revealed a difference in the longitudinal proviral genetic landscape over one year between untreated, late treated, and early treated infection: the relative contribution of intact genomes to the total pool of HIV-1 DNA after 1 year was higher in untreated infection (31%) compared to late treated (14%) and early treated infection (0%). Treatment initiated in both late and early infection resulted in a more rapid decay of intact (13% and 51% per month) versus defective (2% and 35% per month) viral genomes. However, intact genomes were still observed one year post chronic treatment initiation in contrast to early treatment where intact genomes were no longer detectable. Moreover, early ART reduced phylogenetic diversity of intact genomes and limited the seeding and persistence of cytotoxic T lymphocyte immune escape variants in the reservoir. Conclusions: Overall, our results show that whereas ART initiated in hyperacute HIV-1 subtype C infection did not impact reservoir seeding, it was nevertheless associated with more rapid decay of intact viral genomes, decreased genetic complexity and immune escape in reservoirs, which could accelerate reservoir clearance when combined with other interventional strategies.
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Human immunodeficiency virus-1 (HIV-1) clade C is the most prevalent form of HIV-1 comprising nearly 46% of global infections and is the dominant subtype in India. Despite its predominance, the impact of HIV-1 clade C infection on cognitive function has been understudied in comparison with other subtypes, notably clade B, which is primarily found in Europe and North America. Few studies have assessed cognitive impairment in antiretroviral therapy (ART) naïve men and women with HIV-1 clade C infection. In this study conducted in Northern India, differences in neuropsychological functioning were compared between 109 participants (70 men, 39 women) with untreated HIV-1 clade C infection and 110 demographically matched healthy controls (74 men, 36 women). A comprehensive neuropsychological battery was used to examine depression, self-assessment of functioning, and cognitive performance in six domains of functioning. Group differences were assessed by HIV-1 status and sex, controlling for age and education. Results indicated that cognitive deficits were substantially greater among male participants with HIV-1 clade C compared to male controls in all domains of cognitive functioning; in contrast, women with HIV-1 clade C had only minor deficits compared to healthy female participants. In addition, a larger proportion of men with HIV-1 clade C exhibited high levels of depression than women with HIV-1 clade C. These findings suggest that untreated HIV-1 clade C infection in men can have debilitating effects on neuropsychological function and depression, and stress the importance of facilitating rapid access to treatment to reduce the impact of HIV-1 infection.
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Infecciones por VIH , VIH-1 , Humanos , Femenino , Masculino , VIH-1/genética , Caracteres Sexuales , Infecciones por VIH/complicaciones , Infecciones por VIH/tratamiento farmacológico , Cognición , India , Pruebas NeuropsicológicasRESUMEN
Background: To evaluate the usefulness of urine SERPINC1 and ORM1 as biomarkers for early detection of lupus nephritis (LN). Methods: Using proteomics, we screened for potential urine biomarkers that differentiate LN from systemic lupus erythematosus (SLE) patients without nephritis. In addition, urine levels of target biomarkers were measured by ELISA in 13- and 23-week-old MRL-lpr (murine model for LN) and MRL/MpJ mice. Histological analysis was also performed on the kidneys of 23-week-old mice. Results: Urine SERPINC1 and ORM1 were elevated in SLE patients with newly diagnosed LN compared with SLE patients without LN (SERPINC1, AUC=.892, P<.001; ORM1, AUC=.886, P<.001). Levels of urine SERPINC1 and ORM1 were also significantly higher in MRL-lpr mice than in MRL/MpJ mice at 13 and 23 weeks (SERPINC1: p<.01 and p<.001 at 13 and 23 weeks, respectively; ORM1: p<.01 at 13 and 23 weeks). In contrast, a significant difference in urine albumin between the two groups was only observed at 23 weeks (p<.001) not at 13 weeks (p=.83). Regarding the kidney pathology of MPL-lpr mice, urine ORM1 and urine albumin, but not urine SERPINC1, were positively correlated with the activity index (ORM1, rho =.879, p<.001; albumin, rho =.807, p=.003) and chronicity index (ORM1, rho =.947, p<.001; albumin, rho =.869, p<.001). Conclusion: We propose that urine SERPINC1 and ORM1 are novel biomarkers for early LN.
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Lupus Eritematoso Sistémico , Nefritis Lúpica , Humanos , Animales , Ratones , Nefritis Lúpica/diagnóstico , Ratones Endogámicos MRL lpr , Lupus Eritematoso Sistémico/diagnóstico , Albúminas , Biomarcadores , Antitrombina IIIRESUMEN
Despite the fact that many coinfections in people with HIV (PWH) are treatable or suppressible, they may still impact neurocognitive (NC) functioning. Here, we aim to evaluate the presence of latent/treated coinfections and their association with NC functioning in a cohort of PWH in Zambia. We carried out a cross-sectional, nested study involving 151 PWH with viral suppression, and a normative sample of 324 adults without HIV. Plasma samples from PWH who underwent a comprehensive NC assessment were evaluated for the presence of treated/latent coinfections that are common in Zambia. Information about treated pulmonary tuberculosis (TB) was obtained from participants' clinical charts. Overall, PWH differed significantly from the HIV seronegatives on all neuropsychological domains except for fine motor control. ANOVA comparisons of all 3 HIV + groups' demographically corrected mean NC T-scores showed that the HIV + /TB + group had the poorest NC functioning in the following domains: executive functioning (F = 4.23, p = 0.02), working memory (F = 5.05, p = 0.002), verbal fluency (F = 4.24, p = 0.006), learning (F = 11.26, p < 0.001), delayed recall (F = 4.56, p = 0.01), and speed of information processing (F = 5.16, p = 0.005); this group also was substantially worse on the total battery (global mean T-scores; F = 8.02, p < 0.001). In conclusion, treated TB coinfection in PWH was associated with worse NC performance compared to both those with antibodies against other coinfections and without. PWH with antibodies for other coinfections (HIV + /CI +) showed somewhat better NC performance compared to those without (HIV + /CI -), which was not expected, although comparisons with the HIV + /CI + group are limited by its lack of specificity regarding type of coinfection being represented.
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Coinfección , Infecciones por VIH , Adulto , Humanos , Infecciones por VIH/complicaciones , Coinfección/complicaciones , Zambia , Estudios Transversales , Función EjecutivaRESUMEN
Middle East respiratory syndrome coronavirus (MERS-CoV) clade B viruses are found in camelids and humans in the Middle East, but clade C viruses are not. We provide experimental evidence for extended shedding of MERS-CoV clade B viruses in llamas, which might explain why they outcompete clade C strains in the Arabian Peninsula.
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Camélidos del Nuevo Mundo , Infecciones por Coronavirus , Herpesvirus Cercopitecino 1 , Coronavirus del Síndrome Respiratorio de Oriente Medio , Animales , Humanos , Esparcimiento de Virus , CamelusRESUMEN
Ticks of the genus Rhipicephalus infesting cattle are the primary animal pests responsible for the annual economic loss of billions of dollars. Due to the morphological resemblance among the members of the Rhipicephalus (Boophilus) genus, species identification is very difficult. In this study, the adult R. annulatus and R. microplus ticks from two south Indian states viz., Kerala and Karnataka were subjected to morphological and molecular characterization. The R. microplus isolates from south India differed morphologically from true R. microplus clade A ticks. The ventral spur on the first pedipalp observed in male R. microplus was similar to that of R. australis. The phylogenetic analysis revealed that the R. microplus from these states clustered with R. microplus clade C. The mitochondrial cytochrome c oxidase I (COI) was identified as the preferred molecular marker compared to the internal transcribed spacer 2 (ITS2). The interspecific divergence between R. microplus and R. annulatus isolates from South India was 7.9 per cent based on COI. Moreover, based on COI, the R. microplus isolates revealed higher intraspecific divergence (2.9%) than R. annulatus (1%). The ITS2 sequences failed to differentiate R. microplus and R. annulatus.
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Enfermedades de los Bovinos , Rhipicephalus , Infestaciones por Garrapatas , Masculino , Animales , Bovinos , Rhipicephalus/anatomía & histología , Filogenia , India , Enfermedades de los Bovinos/epidemiología , Infestaciones por Garrapatas/epidemiología , Infestaciones por Garrapatas/veterinariaRESUMEN
Blood donations in South Africa are tested for HIV RNA using individual donation NAT (ID-NAT), allowing detection and rapid antiretroviral therapy (ART) of acute HIV infections. We enrolled a cohort of acute and recent HIV-infected blood donation candidates in South Africa in 2015-2018, measured HIV antibody, ID-NAT, and recency of infection <195 days (Sedia LAg) at enrollment and initiated early ART. A small cohort of HIV elite controllers was followed without treatment. HIV reservoir measurements included ultrasensitive plasma RNA, cell-associated HIV RNA, and total DNA. Enrollment of 18 Fiebig I-III and 45 Fiebig IV-VI HIV clade C subjects occurred a median of 18 days after index blood donation. ART was administered successfully and compliance with follow-up visits was excellent. There were only minimal differences in HIV reservoir between ART initiation in Fiebig stages I-III vs. IV-VI, but ART noncompliance increased HIV reservoir. In 11 untreated HIV elite controllers, HIV reservoir levels were similar to or higher than those seen in our early treated cohort. National blood services can identify acute HIV cohorts for subsequent HIV cure research studies. Among HIV clade C-infected donors, HIV reservoir differed little by Fiebig stage at treatment initiation, but was smaller than in chronically treated HIV and those with ART noncompliance.
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Infecciones por VIH , VIH-1 , Humanos , Infecciones por VIH/diagnóstico , Infecciones por VIH/tratamiento farmacológico , Anticuerpos Anti-VIH , VIH-1/genética , ARN , Carga ViralRESUMEN
Stabilized HIV envelope (Env) trimeric protein immunogens have been shown to induce strong autologous neutralizing antibody response. However, there is limited data on the immunogenicity and efficacy of stabilized Env expressed by a viral vector-based immunogen. Here, we compared the immunogenicity and efficacy of two modified vaccinia Ankara (MVA) vaccines based on variable loop 2 hotspot (V2 HS) optimized C.1086 envelope (Env) sequences, one expressing the membrane anchored gp150 (MVA-150) and the other expressing soluble uncleaved pre-fusion optimized (UFO) gp140 trimer (MVA-UFO) in a DNA prime/MVA boost approach against heterologous tier 2 SHIV1157ipd3N4 intrarectal challenges in rhesus macaques (RMs). Both MVA vaccines also expressed SIVmac239 Gag and form virus-like particles. The DNA vaccine expressed SIVmac239 Gag, C.1086 gp160 Env and rhesus CD40L as a built-in adjuvant. Additionally, all immunizations were administered intradermally (ID) to reduce induction of vaccine-specific IFNγ+ CD4 T cell responses. Our results showed that both MVA-150 and MVA-UFO vaccines induce comparable Env specific IgG responses in serum and rectal secretions. The vaccine-induced serum antibody showed ADCC and ADCVI activities against the challenge virus. Comparison with a previous study that used similar immunogens via intramuscular route (IM) showed that ID immunizations induced markedly lower SHIV specific CD4 and CD8 T cell responses compared to IM immunizations. Following challenge, MVA-UFO vaccinated animals showed a significant delay in acquisition of SHIV1157ipd3N4 infection but only in Mamu-A*01 negative macaques with an estimated vaccine efficacy of 64% per exposure. The MVA-150 group also showed a trend (p=0.1) for delay in acquisition of SHIV infection with an estimated vaccine efficacy of 57%. The vaccine-induced IFNγ secreting CD8 T cell responses showed a direct association and CD4 T cells showed an inverse association with delay in acquisition of SHIV infection. These results demonstrated that both MVA-150 and MVA-UFO immunogens induce comparable humoral and cellular immunity and the latter provides marginally better protection against heterologous tier 2 SHIV infection. They also demonstrate that DNA/MVA vaccinations delivered by ID route induce better antibody and lower CD4 and CD8 T cell responses compared to IM.
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VIH-1 , Vacunas de ADN , Vaccinia , Animales , Anticuerpos Antivirales , ADN , VIH-1/genética , Macaca mulatta , Virus Vaccinia/genética , Vacunas ViralesRESUMEN
Stabilization of the HIV-1 Envelope glycoprotein trimer (Env) in its native pre-fusion closed conformation is regarded as one of several requirements for the induction of neutralizing antibody (nAb) responses, which, in turn, will most likely be a prerequisite for the development of an efficacious preventive vaccine. Here, we systematically analyzed how the stepwise stabilization of a clade C consensus (ConC) Env immunogen impacts biochemical and biophysical protein traits such as antigenicity, thermal stability, structural integrity, and particle size distribution. The increasing degree of conformational rigidification positively correlates with favorable protein characteristics, leading to optimized homogeneity of the protein preparations, increased thermal stability, and an overall favorable binding profile of structure-dependent broadly neutralizing antibodies (bnAbs) and non-neutralizing antibodies (non-nAbs). We confirmed that increasing the structural integrity and stability of the Env trimers positively correlates with the quality of induced antibody responses by the immunogens. These and other data contribute to the selection of ConCv5 KIKO as novel Env immunogens for use within the European Union's H2020 Research Consortium EHVA (European HIV Alliance) for further preclinical analysis and phase 1 clinical development.
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BACKGROUND: The potential use of the broadly neutralizing monoclonal antibodies (bnAbs) towards prophylaxis and treatment to HIV-1 is currently being explored. While a number of promising bnAbs have been discovered and a few of them have progressed towards clinical development, their extent of neutralization coverage with respect to global HIV-1 variants given the existence of genetically distinct subtypes and recombinants circulating globally is not clearly known. In the present study, we examined the variation in the neutralization susceptibility of pseudoviruses expressing 71 full length primary HIV-1 subtype C envs obtained from limited cross-sectional individuals over different time points against four bnAbs that target gp120 with distinct specificities: VRC01, CAP256-VRC26.25, PGDM1400 and PGT121. RESULTS: We found significant variations in the susceptibility of Indian clade C to these four bnAbs. These variations were found to be distinct to that observed in African subtype C based on the existing datasets and concordant with their sequence diversity. Trend analysis indicated an increasing neutralization resistance observed over time with CAP25-VRC26.25, PGDM1400 and PGT121 when tested on pseudoviruses expressing envs obtained from 1999 to 2016. However, inconsistent trend in neutralization susceptibility was observed, when pseudoviruses expressing envs obtained from three followed up individuals were examined. Finally, through predictive analysis of the 98 Indian subtype C including those assessed in the present study by employing additive model implemented in CombiNAber ( http://www.hiv.lanl.gov ), we observed two possibilities where combinations of three bnAbs (VRC01/CAP56-VRC26.25/PGT121 and PGDM1400/CAP256-VRC26.25/PGT121) could achieve near 100% neutralization coverage. CONCLUSIONS: Our findings not only indicate disparate intra-clade C genetic vis-à-vis neutralization diversities but also warrant the need for more comprehensive study using additional isolates towards comparing inter and intra-clade neutralization diversities which will be necessary for selecting the bnAb combinations suitable for optimal coverage of the region-specific HIV-1 circulating subtypes. Expanding these efforts is imperative for designing efficacious bnAb based intervention strategies for India as well as subtype C in general.
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Anticuerpos Monoclonales/inmunología , Anticuerpos ampliamente neutralizantes/sangre , Anticuerpos Anti-VIH/sangre , Proteína gp120 de Envoltorio del VIH/inmunología , VIH-1/genética , VIH-1/inmunología , Anticuerpos ampliamente neutralizantes/inmunología , Estudios Transversales , Estudios de Seguimiento , Anticuerpos Anti-VIH/clasificación , Infecciones por VIH/virología , VIH-1/clasificación , Humanos , India , Pruebas de Neutralización , FilogeniaRESUMEN
BACKGROUND: The HIV-1 envelope glycoprotein (Env) is the primary target for broadly neutralizing antibodies (bNAbs) which can block infection. The current design strategy of soluble forms of Env in native-like trimeric conformation induces neutralizing antibodies with minimal breadth and potency. Extensive shielding by N-glycans on the surface of the HIV-1 Env acts as an immune evasion mechanism by restricting B cell recognition of conserved neutralizing determinants. An alternate approach is to design Env protein with glycan deletion to expose the protein surface. METHODS: A stable native-like trimeric Env with glycan holes at potentially immunogenic locations is expected to elicit better induction of germ-line B-cells due to exposure of the immunogenic regions. However, the extent and consequences of glycan removal from the trimer apex that form an important epitope is not explored. In this work, we have designed a construct with glycans deleted from the trimer apex of an Indian clade C origin Env that has previously been characterized for immunogenicity, to understand the impact of deglycosylation on the structural and functional integrity as well as on the antibody binding properties. RESULTS: The V1V2 glycan-deleted protein maintains native-like trimeric conformation with improved accessibility of the V1V2-directed germ-line antibodies. Furthermore, we showed that the protein binds specifically to quaternary conformation-dependent bnAbs but minimally to non-neutralizing antibodies. CONCLUSIONS: This study provide an important design aspect of HIV-1 Env-based immunogens with glycan holes in the apex region that could be useful in eliciting apex directed antibodies in immunization studies.
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Anticuerpos Neutralizantes/inmunología , Infecciones por VIH/virología , VIH-1/inmunología , Polisacáridos/inmunología , Productos del Gen env del Virus de la Inmunodeficiencia Humana/inmunología , Línea Celular , Epítopos/química , Epítopos/genética , Epítopos/inmunología , Infecciones por VIH/inmunología , VIH-1/química , VIH-1/genética , Humanos , Modelos Moleculares , Polisacáridos/química , Polisacáridos/genética , Conformación Proteica , Multimerización de Proteína , Estabilidad Proteica , Productos del Gen env del Virus de la Inmunodeficiencia Humana/química , Productos del Gen env del Virus de la Inmunodeficiencia Humana/genéticaRESUMEN
Human Immunodeficiency Virus-1 Clade C (HIV-1C) dominates the AIDS epidemic in India, afflicting 2.1 million individuals within the country and more than 15 million people worldwide. Membrane proximal external region (MPER) is an attractive target for broadly neutralizing antibody (bNAb) based therapies. However, information on MPER sequence diversity from India is meagre due to limited sampling of primary viral sequences. In the present study, we examined the variation in MPER of HIV-1C from 24 individuals in Mumbai, India by high throughput sequencing of uncultured viral sequences. Deep sequencing of MPER (662-683; HXB2 envelope amino acid numbering) allowed quantification of intra-individual variation up to 65% at positions 662, 665, 668, 674 and 677 within this region. These variable positions included contact sites targeted by bNAbs 2F5, Z13e1, 4E10 as well as 10E8. Both major and minor epitope variants i.e. 'haplotypes' were generated for each sample dataset. A total of 23, 34 and 25 unique epitope haplotypes could be identified for bNAbs 2F5, Z13e1 and 4E10/10E8 respectively. Further analysis of 4E10 and 10E8 epitopes from our dataset and meta-analysis of previously reported HIV-1 sequences from India revealed 26 epitopes (7 India-specific), heretofore untested for neutralization sensitivity. Peptide-Ab docking predicted 13 of these to be non-binding to 10E8. ELISA, Surface Plasmon Resonance and peptide inhibition of HIV-1 neutralization assays were then performed which validated predicted weak/non-binding interactions for peptides corresponding to six of these epitopes. These results highlight the under-representation of 10E8 non-binding HIV-1C MPER sequences from India. Our study thus underscores the need for increased surveillance of primary circulating envelope sequences for development of efficacious bNAb-based interventions in India.
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Anticuerpos ampliamente neutralizantes/metabolismo , Variación Genética , Anticuerpos Anti-VIH/metabolismo , Proteína gp41 de Envoltorio del VIH/genética , Proteína gp41 de Envoltorio del VIH/metabolismo , VIH-1/inmunología , Adulto , Anticuerpos ampliamente neutralizantes/inmunología , Niño , Epítopos/genética , Epítopos/inmunología , Femenino , Anticuerpos Anti-VIH/inmunología , Infecciones por VIH/virología , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos , India , Masculino , Metaanálisis como Asunto , Persona de Mediana Edad , Simulación del Acoplamiento Molecular , Pruebas de NeutralizaciónRESUMEN
Cellular ESCRT machinery plays pivotal role in HIV-1 budding and release. Extracellular stimuli that modulate HIV-1 egress are currently unknown. We found that CCL2 induced by HIV-1 clade B (HIV-1B) infection of macrophages enhanced virus production, while CCL2 immuno-depletion reversed this effect. Additionally, HIV-1 clade C (HIV-1C) was refractory to CCL2 levels. We show that CCL2-mediated increase in virus production requires Gag late motif LYPX present in HIV-1B, but absent in HIV-1C, and ALIX protein that recruits ESCRT III complex. CCL2 immuno-depletion sequestered ALIX to F-actin structures, while CCL2 addition mobilized it to cytoplasm facilitating Gag-ALIX binding. The LYPX motif improves virus replication and its absence renders the virus less fit. Interestingly, novel variants of HIV-1C with PYRE/PYKE tetrapeptide insertions in Gag-p6 conferred ALIX binding, CCL2-responsiveness and enhanced virus replication. These results, for the first time, indicate that CCL2 mediates ALIX mobilization from F-actin and enhances HIV-1 release and fitness.
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Proteínas de Unión al Calcio/metabolismo , Proteínas de Ciclo Celular/metabolismo , Quimiocina CCL2/metabolismo , Complejos de Clasificación Endosomal Requeridos para el Transporte/metabolismo , VIH-1/crecimiento & desarrollo , Interacciones Huésped-Patógeno , Liberación del Virus , Productos del Gen gag del Virus de la Inmunodeficiencia Humana/metabolismo , Células Cultivadas , Humanos , Macrófagos/virologíaRESUMEN
Broadly neutralizing antibodies (bNAbs) have demonstrated protective effects against HIV-1 in primate studies and recent human clinical trials. Elite neutralizers are potential candidates for isolation of HIV-1 bNAbs. The coexistence of bNAbs such as BG18 with neutralization-susceptible autologous viruses in an HIV-1-infected adult elite controller has been suggested to control viremia. Disease progression is faster in HIV-1-infected children than in adults. Plasma bNAbs with multiple epitope specificities are developed in HIV-1 chronically infected children with more potency and breadth than in adults. Therefore, we evaluated the specificity of plasma neutralizing antibodies of an antiretroviral-naive HIV-1 clade C chronically infected pediatric elite neutralizer, AIIMS_330. The plasma antibodies showed broad and potent HIV-1 neutralizing activity with >87% (29/33) breadth, a median inhibitory dilution (ID50) value of 1,246, and presence of N160 and N332 supersite-dependent HIV-1 bNAbs. The sorting of BG505.SOSIP.664.C2 T332N gp140 HIV-1 antigen-specific single B cells of AIIMS_330 resulted in the isolation of an HIV-1 N332 supersite-dependent bNAb, AIIMS-P01. The AIIMS-P01 neutralized 67% of HIV-1 cross-clade viruses, exhibited substantial indels despite limited somatic hypermutations, interacted with native-like HIV-1 trimer as observed in negative stain electron microscopy, and demonstrated high binding affinity. In addition, AIIMS-P01 neutralized the coexisting and evolving autologous viruses, suggesting the coexistence of vulnerable autologous viruses and HIV-1 bNAbs in the AIIMS_330 pediatric elite neutralizer. Such pediatric elite neutralizers can serve as potential candidates for isolation of novel HIV-1 pediatric bNAbs and for understanding the coevolution of virus and host immune response.IMPORTANCE More than 50% of the HIV-1 infections globally are caused by clade C viruses. To date, there is no effective vaccine to prevent HIV-1 infection. Based on the structural information of the currently available HIV-1 bNAbs, attempts are under way to design immunogens that can elicit correlates of protection upon vaccination. Here, we report the isolation and characterization of an HIV-1 N332 supersite-dependent bNAb, AIIMS-P01, from a clade C chronically infected pediatric elite neutralizer. The N332 supersite is an important epitope and is one of the current HIV-1 vaccine targets. AIIMS-P01 potently neutralized the contemporaneous and autologous evolving viruses and exhibited substantial indels despite low somatic hypermutations. Taken together with the information on infant bNAbs, further isolation and characterization of bNAbs contributing to the plasma breadth in HIV-1 chronically infected children may help provide a better understanding of their role in controlling HIV-1 infection.
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Anticuerpos Neutralizantes/uso terapéutico , VIH-1/inmunología , Adulto , Antirretrovirales , Anticuerpos Monoclonales/inmunología , Anticuerpos Neutralizantes/inmunología , Evolución Biológica , Niño , Epítopos/inmunología , Femenino , Anticuerpos Anti-VIH/inmunología , Infecciones por VIH/virología , Seropositividad para VIH , Humanos , Masculino , Pruebas de Neutralización , Vacunación , Viremia , Productos del Gen env del Virus de la Inmunodeficiencia Humana/inmunologíaRESUMEN
The high rate of new HIV infections, particularly in Sub-Saharan Africa, emphasizes the need for a safe and effective vaccine to prevent acquired immunodeficiency syndrome (AIDS). To date, the only HIV vaccine trial that has exhibited protective efficacy in humans was the RV144 study completed in Thailand. The finding that protection correlated with antibodies to gp120 suggested that increasing the quality or magnitude of the antibody response that recognize gp120 might improve the modest yet significant protection (31.2%) achieved with this immunization regimen. However, the large-scale production of rgp120 suitable for clinical trials has been challenging due, in part, to low productivity and difficulties in purification. Moreover, the antigens that are currently available were produced largely by the same technology used in the early 1990s and fail to incorporate unique carbohydrates presented on HIV virions required for the binding of several major families of broadly neutralizing antibodies (bNAbs). Here we describe the development of a high-yielding CHO cell line expressing rgp120 from a clade C isolate (TZ97008), representative of the predominant circulating HIV subtype in Southern Africa and Southeast Asia. This cell line, produced using robotic selection, expresses high levels (1.2 g/L) of the TZ97008 rgp120 antigen that incorporates oligomannose glycans required for binding to multiple glycan dependent bNAbs. The resulting rgp120 displays a lower degree of net charge and glycoform heterogeneity as compared to rgp120s produced in normal CHO cells. This homogeneity in net charge facilitates purification by filtration and ion exchange chromatography methods, eliminating the need for expensive custom-made lectin, or immunoaffinity columns. The results described herein document the availability of a novel cell line for the large-scale production of clade C gp120 for clinical trials. Finally, the strategy used to produce a TZ97008 gp120 in the MGAT- CHO cell line can be applied to the production of other candidate HIV vaccines.
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Anticuerpos Anti-VIH/inmunología , Proteína gp120 de Envoltorio del VIH/biosíntesis , Proteína gp120 de Envoltorio del VIH/inmunología , Infecciones por VIH/inmunología , Infecciones por VIH/metabolismo , VIH-1/inmunología , N-Acetilglucosaminiltransferasas/genética , Secuencia de Aminoácidos , Animales , Anticuerpos Neutralizantes/inmunología , Células CHO , Cricetulus , Genotipo , Glicosilación , Proteína gp120 de Envoltorio del VIH/química , Infecciones por VIH/virología , VIH-1/clasificación , VIH-1/genética , Humanos , N-Acetilglucosaminiltransferasas/metabolismo , Unión ProteicaRESUMEN
Using HIV-1 envelope protein (Env)-based immunogens that closely mimic the conformation of functional HIV-1 Envs and represent the isolates prevalent in relevant geographical region is considered a rational approach towards developing HIV vaccine. We recently reported that like clade B Env, JRFL, membrane bound Indian clade C Env, 4-2.J41 is also efficiently cleaved and displays desirable antigenic properties for plasmid DNA immunization. Here, we evaluated the immune response in rabbit by injecting the animals with plasmid expressing membrane bound efficiently cleaved 4-2.J41 Env followed by its gp140-foldon (gp140-fd) protein boost. The purified 4-2.J41-gp140-fd protein is recognized by a wide panel of broadly neutralizing antibodies (bNAbs) including the quaternary conformation-dependent antibody, PGT145 with high affinity. We have also evaluated and compared the quality of antibody response elicited in rabbits after immunizing with plasmid DNA expressing the membrane bound efficiently cleaved Env followed by gp140-fd proteins boost with either of clade C Env, 4-2.J41 or clade B Env, JRFL or in combination. In comparison to JRFL group, 4-2.J41 group elicited autologous as well as limited low level cross clade neutralizing antibody response. Preliminary epitope-mapping of sera from animals show that in contrast to JRFL group, no reactivity to either linear peptides or V3-loop is detected in 4-2.J41 group. Furthermore, the presence of conformation-specific antibody in sera from animals immunized with 4-2.J41 Env is observed. However, unlike JRFL group, in 4-2.J41 group of animals, CD4-binding site-directed antibodies cannot be detected. Additionally, we have demonstrated that the quality of antibody response in combination group is guided by JRFL Env-based immunogen suggesting that the selection and the quality of Envs in multicade candidate vaccine are important factors to elicit desirable response.
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Epítopos/inmunología , Anticuerpos Anti-VIH/inmunología , Infecciones por VIH/inmunología , Infecciones por VIH/virología , VIH-1/inmunología , Productos del Gen env del Virus de la Inmunodeficiencia Humana/inmunología , Animales , Anticuerpos Neutralizantes/sangre , Anticuerpos Neutralizantes/inmunología , Formación de Anticuerpos , Especificidad de Anticuerpos/inmunología , Mapeo Epitopo , Epítopos/química , Expresión Génica , Genotipo , Anticuerpos Anti-VIH/sangre , VIH-1/clasificación , VIH-1/genética , Humanos , Sueros Inmunes/inmunología , Pruebas de Neutralización , Unión Proteica/inmunología , Multimerización de Proteína , Conejos , Proteínas Recombinantes , Productos del Gen env del Virus de la Inmunodeficiencia Humana/genéticaRESUMEN
Anti-HIV passive immunization with human neutralizing monoclonal antibodies (nmAbs) has made exciting gains: (i) identification of the HIV envelope V2 apex as a new in vivo protective epitope, (ii) a novel clade C SHIV for challenge studies, and (iii) a highly protective, trispecific nmAb. Potent, broad-spectrum protection by nmAbs holds promise.
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Anticuerpos Neutralizantes , VIH-1/inmunología , Anticuerpos Monoclonales , Humanos , Inmunización Pasiva , Pruebas de Neutralización , ArmasRESUMEN
Despite the widespread use of antiretrovirals (ARV), more than 150,000 pediatric HIV-1 infections continue to occur annually. Supplemental strategies are necessary to eliminate pediatric HIV infections. We previously reported that maternal HIV envelope-specific anti-V3 IgG and CD4 binding site-directed antibodies, as well as tier 1 virus neutralization, predicted a reduced risk of mother-to-child transmission (MTCT) of HIV-1 in the pre-ARV era U.S.-based Women and Infants Transmission Study (WITS) cohort. As the majority of ongoing pediatric HIV infections occur in sub-Saharan Africa, we sought to determine if the same maternal humoral immune correlates predicted MTCT in a subset of the Malawian Breastfeeding, Antiretrovirals, and Nutrition (BAN) cohort of HIV-infected mothers (n = 88, with 45 transmitting and 43 nontransmitting). Women and infants received ARV at delivery; thus, the majority of MTCT was in utero (91%). In a multivariable logistic regression model, neither maternal anti-V3 IgG nor clade C tier 1 virus neutralization was associated with MTCT. Unexpectedly, maternal CD4 binding-site antibodies and anti-variable loop 1 and 2 (V1V2) IgG were associated with increased MTCT, independent of maternal viral load. Neither infant envelope (Env)-specific IgG levels nor maternal IgG transplacental transfer efficiency was associated with transmission. Distinct humoral immune correlates of MTCT in the BAN and WITS cohorts could be due to differences between transmission modes, virus clades, or maternal antiretroviral use. The association between specific maternal antibody responses and in utero transmission, which is distinct from potentially protective maternal antibodies in the WITS cohort, underlines the importance of investigating additional cohorts with well-defined transmission modes to understand the role of antibodies during HIV-1 MTCT.
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Anticuerpos Anti-VIH/sangre , Infecciones por VIH/inmunología , Infecciones por VIH/transmisión , VIH-1/inmunología , Inmunidad Humoral , Transmisión Vertical de Enfermedad Infecciosa , Complicaciones Infecciosas del Embarazo/inmunología , Adulto , Fármacos Anti-VIH/uso terapéutico , Anticuerpos Neutralizantes/inmunología , Lactancia Materna , Estudios de Cohortes , Femenino , Anticuerpos Anti-VIH/biosíntesis , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/virología , Humanos , Inmunoglobulina G/sangre , Lactante , Periodo Periparto , Embarazo , Carga ViralRESUMEN
The development of soluble envelope glycoprotein (Env) mimetics displaying ordered trimeric symmetry has ushered in a new era in HIV-1 vaccination. The recently reported native, flexibly linked (NFL) design allows the generation of native-like trimers from clinical isolates at high yields and homogeneity. As the majority of infections world-wide are of the clade C subtype, we examined responses in non-human primates to well-ordered subtype C 16055 trimers administered in soluble or high-density liposomal formats. We detected superior germinal center formation and enhanced autologous neutralizing antibodies against the neutralization-resistant (tier 2) 16055 virus following inoculation of liposome-arrayed trimers. Epitope mapping of the neutralizing monoclonal antibodies (mAbs) indicated major contacts with the V2 apex, and 3D electron microscopy reconstructions of Fab-trimer complexes revealed a horizontal binding angle to the Env spike. These vaccine-elicited mAbs target the V2 cap, demonstrating a means to accomplish tier 2 virus neutralization by penetrating the dense N-glycan shield.
Asunto(s)
Anticuerpos Neutralizantes/inmunología , Anticuerpos Anti-VIH/inmunología , VIH-1/inmunología , Fragmentos de Péptidos/inmunología , Multimerización de Proteína/inmunología , Productos del Gen env del Virus de la Inmunodeficiencia Humana/química , Productos del Gen env del Virus de la Inmunodeficiencia Humana/inmunología , Anticuerpos Neutralizantes/química , Anticuerpos Neutralizantes/metabolismo , Mapeo Epitopo , Epítopos/química , Epítopos/inmunología , Anticuerpos Anti-VIH/química , Anticuerpos Anti-VIH/metabolismo , VIH-1/clasificación , VIH-1/genética , Humanos , Inmunización , Modelos Moleculares , Simulación del Acoplamiento Molecular , Fragmentos de Péptidos/química , Fragmentos de Péptidos/metabolismo , Unión Proteica , Conformación Proteica , Virión/química , Virión/inmunología , Virión/ultraestructura , Productos del Gen env del Virus de la Inmunodeficiencia Humana/genéticaRESUMEN
Controversy remains regarding the neurotoxicity of clade C human immunodeficiency virus (HIV-C). When examined in preclinical studies, a cysteine to serine substitution in the C31 dicysteine motif of the HIV-C Tat protein (C31S) results in less severe brain injury compared to other viral clades. By contrast, patient cohort studies identify significant neuropsychological impairment among HIV-C individuals independent of Tat variability. The present study clarified this discrepancy by examining neuroimaging markers of brain integrity among HIV-C individuals with and without the Tat substitution. Thirty-seven HIV-C individuals with the Tat C31S substitution, 109 HIV-C individuals without the Tat substitution (C31C), and 34 HIV- controls underwent 3T structural magnetic resonance imaging (MRI) and diffusion tensor imaging (DTI). Volumes were determined for the caudate, putamen, thalamus, corpus callosum, total gray matter, and total white matter. DTI metrics included fractional anisotropy (FA), radial diffusivity (RD), and axial diffusivity (AD). Tracts of interest included the anterior thalamic radiation (ATR), cingulum bundle (CING), uncinate fasciculus (UNC), and corpus callosum (CC). HIV+ individuals exhibited smaller volumes in subcortical gray matter, total gray matter and total white matter compared to HIV- controls. HIV+ individuals also exhibited DTI abnormalities across multiple tracts compared to HIV- controls. By contrast, neither volumetric nor diffusion indices differed significantly between the Tat C31S and C31C groups. Tat C31S status is not a sufficient biomarker of HIV-related brain integrity in patient populations. Clinical attention directed at brain health is warranted for all HIV+ individuals, independent of Tat C31S or clade C status.