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Existing approaches to identifying predictive T-cell epitopes have traditionally utilized either 2-digit HLA super-families or more commonly utilizing autologous HLA alleles to facilitate the predictions. However, the use of these criteria may not consider the HLA representation within any target population. Here we propose a modification to concept of utilizing autologous HLA whereby subsets of individuals are selected for their specific HLA allele profiles and the representation they provide within a given population. Using this selective approach to HLA selection and the linkages to specific individuals may enable the design of more targeted experimentalstrategies.
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Epitopos de Linfócito T , Antígeno HLA-A2 , Alelos , Antígenos de Histocompatibilidade , Antígenos de Histocompatibilidade Classe I , HumanosRESUMO
Cytotoxic T lymphocytes (CTLs) are a critical arm of the immune response to viral infections. The activation and expansion of antigen specific CTL requires recognition of peptide antigens presented on class I major histocompatibility complex molecules (MHC-1) of infected cells. Methods to identify presented peptide antigens that do not rely on the pre-existence of antigen specific CTL are critical to the development of new vaccines. We infected activated CD4+ T cells with two HIV-1 transmitted founder (TF) isolates and used high-resolution mass spectrometry (MS) to identify HIV peptides bound on MHC-1. Using this approach, we identified 14 MHC-1 bound peptides from across the two TF isolates. Assessment of predicted binding thresholds revealed good association of the identified peptides to the shared HLA alleles between the HIV+ donors and the naïve PBMC sample with three peptides identified through peptide sequencing inducing a CD8 T-cell response (p < 0.05). Direct infection of naïve CD4 cells by HIV TF isolates and sequencing of MHC-I presented peptides by HPLC-MS/MS enables identification of novel peptides that may be missed by alternative epitope mapping strategies and can provide valuable insight in to the first peptides presented by an HIV-infected CD4 cell in the first few days post infection.
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HIV-1 , Linfócitos T CD8-Positivos , Epitopos de Linfócito T , Leucócitos Mononucleares , Espectrometria de Massas em TandemRESUMO
BACKGROUND: Acute retroviral syndrome (ARS) is associated with human immunodeficiency virus type 1 (HIV-1) subtype and disease progression, but the underlying immunopathological pathways are poorly understood. We aimed to elucidate associations between innate immune responses during hyperacute HIV-1 infection (hAHI) and ARS. METHODS: Plasma samples obtained from volunteers (≥18.0 years) before and during hAHI, defined as HIV-1 antibody negative and RNA or p24 antigen positive, from Kenya, Rwanda, Uganda, Zambia, and Sweden were analyzed. Forty soluble innate immune markers were measured using multiplexed assays. Immune responses were differentiated into volunteers with stronger and comparatively weaker responses using principal component analysis. Presence or absence of ARS was defined based on 11 symptoms using latent class analysis. Logistic regression was used to determine associations between immune responses and ARS. RESULTS: Of 55 volunteers, 31 (56%) had ARS. Volunteers with stronger immune responses (nâ =â 36 [65%]) had increased odds of ARS which was independent of HIV-1 subtype, age, and risk group (adjusted odds ratio, 7.1 [95% confidence interval {CI}: 1.7-28.8], Pâ =â .003). Interferon gamma-induced protein (IP)-10 was 14-fold higher during hAHI, elevated in 7 of the 11 symptoms and independently associated with ARS. IP-10 threshold >466.0 pg/mL differentiated stronger immune responses with a sensitivity of 84.2% (95% CI: 60.4-96.6) and specificity of 100.0% (95% CI]: 90.3-100.0). CONCLUSIONS: A stronger innate immune response during hAHI was associated with ARS. Plasma IP-10 may be a candidate biomarker of stronger innate immunity. Our findings provide further insights on innate immune responses in regulating ARS and may inform the design of vaccine candidates harnessing innate immunity.
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Síndrome Retroviral Aguda , Infecções por HIV , HIV-1 , Quimiocina CXCL10 , Humanos , Imunidade InataRESUMO
BACKGROUND: The HIV-1 epidemic in sub-Saharan Africa is heterogeneous with diverse unevenly distributed subtypes and regional differences in prevalence. Subtype-specific differences in disease progression rate and transmission efficiency have been reported, but the underlying biological mechanisms have not been fully characterized. Here, we tested the hypothesis that the subtypes prevalent in the East Africa, where adult prevalence rate is higher, have lower viral replication capacity (VRC) than their West African counterparts where adult prevalence rates are lower. RESULTS: Gag-protease sequencing was performed on 213 and 160 antiretroviral-naïve chronically infected participants from West and East Africa respectively and bioinformatic tools were used to infer subtypes and recombination patterns. VRC of patient-derived gag-protease chimeric viruses from West (n = 178) and East (n = 114) Africa were determined using a green fluorescent protein reporter-based cell assay. Subtype and regional differences in VRC and amino acid variants impacting VRC were identified by statistical methods. CRF02_AG (65%, n = 139), other recombinants (14%, n = 30) and pure subtypes (21%, n = 44) were identified in West Africa. Subtypes A1 (64%, n = 103), D (22%, n = 35), or recombinants (14%, n = 22) were identified in East Africa. Viruses from West Africa had significantly higher VRC compared to those from East Africa (p < 0.0001), with subtype-specific differences found among strains within West and East Africa (p < 0.0001). Recombination patterns showed a preference for subtypes D, G or J rather than subtype A in the p6 region of gag, with evidence that subtype-specific differences in this region impact VRC. Furthermore, the Gag A83V polymorphism was associated with reduced VRC in CRF02_AG. HLA-A*23:01 (p = 0.0014) and HLA-C*07:01 (p = 0.002) were associated with lower VRC in subtype A infected individuals from East Africa. CONCLUSIONS: Although prevalent viruses from West Africa displayed higher VRC than those from East Africa consistent with the hypothesis that lower VRC is associated with higher population prevalence, the predominant CRF02_AG strain in West Africa displayed higher VRC than other prevalent strains suggesting that VRC alone does not explain population prevalence. The study identified viral and host genetic determinants of virus replication capacity for HIV-1 CRF02_AG and subtype A respectively, which may have relevance for vaccine strategies.
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Protease de HIV/genética , HIV-1/genética , HIV-1/fisiologia , Replicação Viral/genética , Produtos do Gene gag do Vírus da Imunodeficiência Humana/genética , Adulto , África Oriental , África Ocidental , Estudos Transversais , Feminino , Genótipo , Infecções por HIV/virologia , Protease de HIV/classificação , HIV-1/classificação , HIV-1/enzimologia , Humanos , Masculino , Filogenia , Recombinação Genética , Estudos Retrospectivos , Replicação Viral/fisiologia , Adulto Jovem , Produtos do Gene gag do Vírus da Imunodeficiência Humana/classificaçãoRESUMO
Atlantic bluefin tuna are a symbol of both the conflict between preservationist and utilitarian views of top ocean predators, and the struggle to reach international consensus on the management of migratory species. Currently, Atlantic bluefin tuna are managed as an early-maturing eastern stock, which spawns in the Mediterranean Sea, and a late-maturing western stock, which spawns in the Gulf of Mexico. However, electronic tagging studies show that many bluefin tuna, assumed to be of a mature size, do not visit either spawning ground during the spawning season. Whether these fish are spawning in an alternate location, skip-spawning, or not spawning until an older age affects how vulnerable this species is to anthropogenic stressors including exploitation. We use larval collections to demonstrate a bluefin tuna spawning ground in the Slope Sea, between the Gulf Stream and northeast United States continental shelf. We contend that western Atlantic bluefin tuna have a differential spawning migration, with larger individuals spawning in the Gulf of Mexico, and smaller individuals spawning in the Slope Sea. The current life history model, which assumes only Gulf of Mexico spawning, overestimates age at maturity for the western stock. Furthermore, individual tuna occupy both the Slope Sea and Mediterranean Sea in separate years, contrary to the prevailing view that individuals exhibit complete spawning-site fidelity. Overall, this complexity of spawning migrations questions whether there is complete independence in the dynamics of eastern and western Atlantic bluefin tuna and leads to lower estimates of the vulnerability of this species to exploitation and other anthropogenic stressors.
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Migração Animal , Atum/fisiologia , Animais , Oceano Atlântico , ReproduçãoRESUMO
Theoretical studies suggest that the abrupt and substantial changes in the productivity of some fisheries species may be explained by predation-driven alternate stable states in their population levels. With this hypothesis, an increase in fishing or a natural perturbation can drive a population from an upper to a lower stable-equilibrium population level. After fishing is reduced or the perturbation ended, this low population level can persist due to the regulatory effect of the predator. Although established in theoretical studies, there is limited empirical support for predation-driven alternate stable states in exploited marine fish populations. We present evidence that egg predation by haddock (Melanogrammus aeglefinus) can cause alternate stable population levels in Georges Bank Atlantic herring (Clupea harengus). Egg predation by haddock explains a substantial decoupling of herring spawning stock biomass (an index of egg production) from observed larval herring abundance (an index of egg hatching). Estimated egg survival rates ranged from <2-70% from 1971 to 2005. A population model incorporating egg predation and herring fishing explains the major population trends of Georges Bank herring over four decades and predicts that, when the haddock population is high, seemingly conservative levels of fishing can still precipitate a severe decline in the herring population. These findings illustrate how efforts to rebuild fisheries can be undermined by not incorporating ecological interactions into fisheries models and management plans.
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Pesqueiros/métodos , Peixes , Óvulo , Comportamento Predatório , Animais , Modelos Teóricos , Dinâmica PopulacionalRESUMO
The development, manufacture, and deployment of new vaccine technologies to combat SARS-CoV-2 enabled an unparalleled rapid response to the emerging health threat. However, the unequal global distribution of these vaccines highlighted a major gap in existing thermotolerance profiles and cold chain infrastructure that needs to be addressed to maximize their global health impact.
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Vacinas contra COVID-19 , COVID-19 , SARS-CoV-2 , Vacinas contra COVID-19/imunologia , Humanos , COVID-19/prevenção & controle , COVID-19/epidemiologia , COVID-19/imunologia , SARS-CoV-2/imunologia , Temperatura , Equidade em SaúdeRESUMO
Tubulointerstitial fibrosis is a classic histologic feature of chronic kidney disease (CKD) in cats and a final common pathway toward end-stage renal disease. Domesticated cats have been used in models of ischemia-induced renal fibrosis. The objective of this study was to evaluate the performance of 2 variations of a transient unilateral renal ischemia and delayed contralateral nephrectomy model of tubulointerstitial fibrosis in cats. Purpose-bred, young adult, domesticated cats underwent 90 min of surgically induced ischemia to the right kidney followed by delayed contralateral nephrectomy performed 21 d (RI-CN21d group; n = 10) or 90 d postischemia (RI-CN90d group; n = 12). Control cats underwent sham surgery followed by left nephrectomy 21 d after (sham-CN group; n = 3). Renal functional parameters, including glomerular filtration rate and serum creatinine concentration, were evaluated before and after surgeries. The right kidneys were harvested 120 d postischemia/sham. Renal histology with lesion scoring and histomorphometry for quantification of smooth muscle actin immunolabeling and collagen staining were performed on harvested kidneys. Severe acute kidney injury prompted euthanasia after left nephrectomy in 5/10 (50.0%), 2/12 (16.7%), and 0/3 (0%) of cats in the RI-CN21d, RI-CN90d, and sham-CN groups, respectively. A significant decrease in glomerular filtration rate by day 120, relative to baseline, occurred in cats in the RI-CN21d group (P < 0.001) and RI-CN90d group (P < 0.001) but not the sham-CN group (P = 0.76). All but one cat in the ischemia groups were azotemic at the study end. Kidneys subjected to ischemia had higher interstitial inflammation, tubular atrophy, and fibrosis scores compared with sham-operated kidneys. There were significant increases in smooth muscle actin immunolabeling and collagen staining in these kidneys, relative to the contralateral kidneys. In summary, 90 min of unilateral renal ischemia and delayed contralateral nephrectomy induced histologic and biochemical changes consistent with CKD in cats. A 90-d period between ischemia and nephrectomy resulted in improved survivability of the model.
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The ability to support a comprehensive vaccine research and development (R&D) portfolio from a health security perspective has taken on enhanced significance over the past 3 years whereby countries that had existing vaccine R&D infrastructure (G7, Russia and China) have been at the forefront of global efforts to combat COVID-19. Few countries outside of these key players have the infrastructure necessary to develop national vaccine programs, though this is beginning to change with investment across many low- and middle-income countries. These same opportunities exist for countries in Central and West Asia, and in this perspective, we highlight the existing infrastructure and expertise across seven countries (Armenia, Azerbaijan, Georgia, Kazakhstan, Kyrgyzstan, Tajikistan, and Uzbekistan) and propose opportunities for enhanced collaboration along with a bold proposal for establishing a new-build, regional vaccine translational research institute to facilitate the development of a robust, regional vaccine R&D environment to combat existing and future health challenges.
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COVID-19 , Vacinas , Humanos , COVID-19/prevenção & controle , Federação Russa , Cazaquistão , PesquisaRESUMO
A Quick Assessment of Vaccine Hesitancy approach was developed to collect population insights on vaccination hesitancy for low resource environments. Insights into COVID-19 vaccine hesitancy were collected through online webinars with heads of healthcare departments and anonymized online surveys of healthcare managers (HCM) and primary healthcare workers (HCW) in four countries in Central and West Asia (Armenia, Georgia, Tajikistan, and Kyrgyzstan) between 28 February 2022 and 29 March 2022. From the responses to the survey some key themes identified that underpinned in vaccine hesitancy across the region were perceived understanding of vaccine efficacy, conflict with individual religious beliefs, concerns for side effects, and the relatively rapid development of the vaccine and that improving communications strategies to address these concerns would be critical in combatting vaccine hesitancy through any future public health emergencies.
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Vacinas contra COVID-19 , COVID-19 , Humanos , COVID-19/epidemiologia , COVID-19/prevenção & controle , Pessoal de Saúde , Programas de Imunização , ÁsiaRESUMO
Introduction: The impact of exposure to endemic infections on basal immunity and susceptibility to HIV-1 acquisition remains uncertain. We hypothesized that exposure to infections such as cytomegalovirus (CMV), malaria and sexually transmitted infections (STIs) in high-risk individuals may modulate immunity and subsequently increase susceptibility to HIV-1 acquisition. Methods: A case-control study nested in an HIV-1 negative high-risk cohort from Coastal Kenya was used. Cases were defined as volunteers who tested HIV-1 positive during follow-up and had a plasma sample collected 3 ± 2 months prior to the estimated date of HIV-1 infection. Controls were individuals who remained HIV-1 negative during the follow-up and were matched 2:1 to cases by sex, age, risk group and follow-up time. STI screening was performed using microscopic and serologic tests. HIV-1 pre-infection plasma samples were used to determined exposure to CMV and malaria using enzyme-linked immunosorbent assays and to quantify forty-one cytokines and soluble factors using multiplexing assays. Multiplexing data were analyzed using principal component analysis. Associations between cytokines and soluble factors with subsequent HIV-1 acquisition were determined using conditional logistic regression models. Results and discussion: Overall, samples from 47 cases and 94 controls were analyzed. While exposure to malaria (p=0.675) and CMV (p=0.470) were not associated with HIV-1 acquisition, exposure to STIs was (48% [95% CI, 33.3 - 63] vs. 26% [95% CI, 17.3 - 35.9]. Ten analytes were significantly altered in cases compared to controls and were clustered into four principal components: PC1 (VEGF, MIP-1ß, VEGF-C and IL-4), PC2 (MCP-1, IL-2 and IL-12p70), PC3 (VEGF-D) and PC4 (Eotaxin-3). PC1, which is suggestive of a Th2-modulatory pathway, was significantly associated with HIV-1 acquisition after controlling for STIs (adjusted odds ratio, (95% CI), p-value: 1.51 [1.14 - 2.00], p=0.004). Elevation of Th2-associated pathways may dampen responses involved in viral immunity, leading to enhanced susceptibility to HIV-1 acquisition. Immunomodulatory interventions aimed at inhibiting activation of Th2-associated pathways may be an additional strategy to STI control for HIV-1 prevention and may reduce dampening of immune responses to vaccination.
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Síndrome da Imunodeficiência Adquirida , Infecções por Citomegalovirus , Infecções por HIV , Soropositividade para HIV , HIV-1 , Malária , Infecções Sexualmente Transmissíveis , Humanos , Quênia/epidemiologia , Estudos de Casos e Controles , Infecções Sexualmente Transmissíveis/complicações , Infecções por HIV/prevenção & controle , Citomegalovirus , Síndrome da Imunodeficiência Adquirida/complicações , Interleucina-12 , Infecções por Citomegalovirus/complicações , Malária/epidemiologiaRESUMO
BACKGROUND: The majority of critical care air transport (CCAT) flights are regulated, meaning that a theater-validating flight surgeon has confirmed that the patient is medically cleared for flight and that evacuation is appropriate. If the conditions on the ground do not allow for this process, the flight is unregulated. Published data are limited regarding CCAT unregulated missions to include the period of troop drawdown at the end of the Afghanistan conflict. The objective of our study was to characterize the unregulated missions within Afghanistan during troop drawdown and compare them to regulated missions during the same timeframe. STUDY DESIGN: We performed a retrospective review of all CCAT medical records of patients transported via CCAT within Afghanistan between January 2017 and December 2019. We abstracted data from the records, including mission characteristics, patient demographics, injury descriptors, preflight military treatment facility procedures, CCAT procedures, in-flight CCAT treatments, in-flight events, and equipment issues. Following descriptive and comparative analysis, a Cochran-Armitage test was performed to evaluate the statistical significance of the trend in categorical data over time. Multivariable regression was used to assess the association between vasopressors and preflight massive transfusions, preflight surgical procedures, injury patterns, and age. RESULTS: We reviewed 147 records of patients transported via CCAT: 68 patients were transported in a regulated fashion and 79 on an unregulated flight. The number of patients evacuated increased year-over-year (n = 22 in 2017, n = 57 in 2018, and n = 68 in 2019, P < .001), and the percentage of missions that were unregulated grew geometrically (14%, n = 3 in 2017; 37%, n = 21 in 2018; and 81%, n = 55 in 2019, P < .001). During the time studied, CCAT teams were being used more to decompress forward surgical teams (FST) and, therefore, they were transporting patients just hours following initial damage control surgery in an unregulated fashion. In 2 instances, CCAT decompressed an FST following a mass casualty, during which aeromedical evacuation (AE) crews assisted with patient care. For the regulated missions, the treatments that were statistically more common were intravenous fluids, propofol, norepinephrine, any vasopressors, and bicarbonate. During unregulated missions, the statistically more common treatments were ketamine, fentanyl, and 3% saline. Additional analysis of the mechanically ventilated patient subgroup revealed that vasopressors were used twice as often on regulated (38%) vs. unregulated (13%) flights. Multivariable regression analysis demonstrated that traumatic brain injury (TBI) was the only significant predictor of in-flight vasopressor use (odds ratio = 3.53, confidence interval [1.22, 10.22], P = .02). CONCLUSION: During the troop drawdown in Afghanistan, the number of unregulated missions increased geometrically because the medical footprint was decreasing. During unregulated missions, CCAT providers used ketamine more frequently, consistent with Tactical Combat Casualty Care guidelines. In addition, TBI was the only predictor of vasopressor use and may reflect an attempt to adhere to unmonitored TBI clinical guidelines. Interoperability between CCAT and AE teams is critical to meet mass casualty needs in unregulated mission environments and highlights a need for joint training. It remains imperative to evaluate changes in mission requirements to inform en route combat casualty care training.
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Resgate Aéreo , Lesões Encefálicas Traumáticas , Ketamina , Militares , Humanos , Afeganistão , Estudos Retrospectivos , Cuidados Críticos/métodosRESUMO
INTRODUCTION: Understanding usage patterns of current paper-based documentation can inform the development of electronic documentation forms for en route care. The primary objective was to analyze the frequency of use of each field within the 3899 L Patient Movement Record documented by en route Critical Care Air Transport Teams. Secondary objectives were to identify rarely utilized form fields and to analyze the proportion of verifiable major events documented within the 3899 L form. MATERIALS AND METHODS: We performed a retrospective review of 3899 L patient movement records for patients transported via Critical Care Air Transport Teams from January 2019 to December 2019. Scanned 3899 L forms were manually transcribed into a Microsoft Access database for evaluation and analysis. Proportions were calculated for completed fields. Major vital sign event frequency was compared for checkbox fields versus the vital sign flow sheet for each patient. We performed descriptive analyses for the proportion of charts with completed documentation in each evaluated field and the proportion of flow sheet events documented in major event fields. RESULTS: We analyzed 130 records. Fourteen of 18 (77.8%) demographic fields had a 75% or greater completion ratio. Sections with the largest proportion of rarely or never utilized fields (<1.5% completed) were procedures (77.8% of fields) and major events (63.9% of fields). Major event checkboxes had low sensitivity for documented events in the flow sheet: Change in heart rate greater than 20% (1 of 28 patients); increase in the fraction of inspired oxygen requirement of greater than 10% (6 of 23 patients); decrease in mean arterial pressure of greater than 20% (1 in 12 patients); and temperature less than 35.6°C (1 in 13 patients). CONCLUSIONS: Many of the current 3899 L fields are highly utilized, but some 3899 L sections contain high proportions of rarely utilized fields. Major event checkboxes did not consistently capture events documented within the in-flight vital sign flow sheet.
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Resgate Aéreo , Humanos , Cuidados Críticos/métodos , Estudos Retrospectivos , Prontuários MédicosRESUMO
INTRODUCTION: Inappropriate fluid management during patient transport may lead to casualty morbidity. Percent systolic pressure variation (%SPV) is one of several technologies that perform a dynamic assessment of fluid responsiveness (FT-DYN). Trained anesthesia providers can visually estimate and use %SPV to limit the incidence of erroneous volume management decisions to 1-4%. However, the accuracy of visually estimated %SPV by other specialties is unknown. The aim of this article is to determine the accuracy of estimated %SPV and the incidence of erroneous volume management decisions for Critical Care Air Transport (CCAT) team members before and after training to visually estimate and utilize %SPV. MATERIAL AND METHODS: In one sitting, CCAT team providers received didactics defining %SPV and indicators of fluid responsiveness and treatment with %SPV ≤7 and ≥14.5 defining a fluid nonresponsive and responsive patient, respectively; they were then shown ten 45-second training arterial waveforms on a simulated Propaq M portable monitor's screen. Study subjects were asked to visually estimate %SPV for each arterial waveform and queried whether they would treat with a fluid bolus. After each training simulation, they were told the true %SPV. Seven days post-training, the subjects were shown a different set of ten 45-second testing simulations and asked to estimate %SPV and choose to treat, or not. Nonparametric limits of agreement for differences between true and estimated %SPV were analyzed using Bland-Altman graphs. In addition, three errors were defined: (1) %SPV visual estimate errors that would label a volume responsive patient as nonresponsive, or vice versa; (2) incorrect treatment decisions based on estimated %SPV (algorithm application errors); and (3) incorrect treatment decisions based on true %SPV (clinically significant treatment errors). For the training and testing simulations, these error rates were compared between, and within, provider groups. RESULTS: Sixty-one physicians (MDs), 64 registered nurses (RNs), and 53 respiratory technicians (RTs) participated in the study. For testing simulations, the incidence and 95% CI for %SPV estimate errors with sufficient magnitude to result in a treatment error were 1.4% (0.5%, 3.2%), 1.6% (0.6%, 3.4%), and 4.1% (2.2%, 6.9%) for MDs, RNs, and RTs, respectively. However, clinically significant treatment errors were statistically more common for all provider types, occurring at a rate of 7%, 10%, and 23% (all P < .05). Finally, students did not show clinically relevant reductions in their errors between training and testing simulations. CONCLUSIONS: Although most practitioners correctly visually estimated %SPV and all students completed the training in interpreting and applying %SPV, all groups persisted in making clinically significant treatment errors with moderate to high frequency. This suggests that the treatment errors were more often driven by misapplying FT-DYN algorithms rather than by inaccurate visual estimation of %SPV. Furthermore, these errors were not responsive to training, suggesting that a decision-making cognitive aid may improve CCAT teams' ability to apply FT-DYN technologies.
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Background: Due to COVID-19, pandemic preparedness emerges as a key imperative, necessitating new approaches to accelerate development of reagents against infectious pathogens. Methods: Here, we developed an integrated approach combining synthetic, computational and structural methods with in vitro antibody selection and in vivo immunization to design, produce and validate nature-inspired nanoparticle-based reagents against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Results: Our approach resulted in two innovations: (i) a thermostable nasal vaccine called ADDoCoV, displaying multiple copies of a SARS-CoV-2 receptor binding motif derived epitope and (ii) a multivalent nanoparticle superbinder, called Gigabody, against SARS-CoV-2 including immune-evasive variants of concern (VOCs). In vitro generated neutralizing nanobodies and electron cryo-microscopy established authenticity and accessibility of epitopes displayed by ADDoCoV. Gigabody comprising multimerized nanobodies prevented SARS-CoV-2 virion attachment with picomolar EC50. Vaccinating mice resulted in antibodies cross-reacting with VOCs including Delta and Omicron. Conclusion: Our study elucidates Adenovirus-derived dodecamer (ADDomer)-based nanoparticles for use in active and passive immunization and provides a blueprint for crafting reagents to combat respiratory viral infections.
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PrEPVacc is an international, multi-centre, double-blind vaccine study comparing experimental combination vaccine regimens including DNA/AIDSVAX BE and DNA/CN54gp140 with placebo control. Simultaneously, daily oral PrEP is compared for efficacy against daily Truvada in the context of the current PrEP availability situation at the study sites. An important clinical trial outcome is the accurate measurement of in vivo antibody titer induced through vaccination. Here we report the validation of two ELISAs for CN54gp140 and AIDSVAX BE at Uganda Virus Research Institute that demonstrates precision, specificity, and robustness for assessing the reciprocal antibody end point titer in human serum. This is a critical endpoint for determining whether vaccination can provide any protection against HIV in populations at risk of acquiring HIV.
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Vacinas contra a AIDS , Infecções por HIV , HIV-1 , Humanos , Formação de Anticorpos , Método Duplo-Cego , Ensaio de Imunoadsorção EnzimáticaRESUMO
Objective: The observation that HIV-1 subtype D progresses faster to disease than subtype A prompted us to examine cytokine levels early after infection within the predominant viral subtypes that circulate in Uganda and address the following research questions: (1) Do cytokine levels vary between subtypes A1 and D? (2) Do cytokine profiles correlate with disease outcomes? Methods: To address these questions, HIV-1 subtypes were determined by population sequencing of the HIV-1 pol gene and 37 plasma cytokine concentrations were evaluated using V-Plex kits on Meso Scale Discovery platform in 65 recent sero-converters. Results: HIV-1 subtype D (pol) infections exhibited significantly higher median plasma concentrations of IL-5, IL-16, IL-1α, IL-7, IL-17A, CCL11 (Eotaxin-1), CXCL10 (IP-10), CCL13 (MCP-4) and VEGF-D compared to subtype A1 (pol) infections. We also found that IL-12/23p40 and IL-1α were associated with faster CD4+T cell count decline, while bFGF was associated with maintenance of CD4+ counts above 350 cells/microliter. Conclusion: Our results suggest that increased production of cytokines in early HIV infection may trigger a disruption of the immune environment and contribute to pathogenic mechanisms underlying the accelerated disease progression seen in individuals infected with HIV-1 subtype D in Uganda.