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1.
PLoS Pathog ; 20(4): e1012134, 2024 Apr 11.
Artículo en Inglés | MEDLINE | ID: mdl-38603762

RESUMEN

Monoclonal antibodies (mAbs) are an important class of antiviral therapeutics. MAbs are highly selective, well tolerated, and have long in vivo half-life as well as the capacity to induce immune-mediated virus clearance. Their activities can be further enhanced by integration of their variable fragments (Fvs) into bispecific antibodies (bsAbs), affording simultaneous targeting of multiple epitopes to improve potency and breadth and/or to mitigate against viral escape by a single mutation. Here, we explore a bsAb strategy for generation of pan-ebolavirus and pan-filovirus immunotherapeutics. Filoviruses, including Ebola virus (EBOV), Sudan virus (SUDV), and Marburg virus (MARV), cause severe hemorrhagic fever. Although there are two FDA-approved mAb therapies for EBOV infection, these do not extend to other filoviruses. Here, we combine Fvs from broad ebolavirus mAbs to generate novel pan-ebolavirus bsAbs that are potently neutralizing, confer protection in mice, and are resistant to viral escape. Moreover, we combine Fvs from pan-ebolavirus mAbs with those of protective MARV mAbs to generate pan-filovirus protective bsAbs. These results provide guidelines for broad antiviral bsAb design and generate new immunotherapeutic candidates.

2.
Nat Microbiol ; 9(3): 751-762, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38326571

RESUMEN

Infection with Lassa virus (LASV) can cause Lassa fever, a haemorrhagic illness with an estimated fatality rate of 29.7%, but causes no or mild symptoms in many individuals. Here, to investigate whether human genetic variation underlies the heterogeneity of LASV infection, we carried out genome-wide association studies (GWAS) as well as seroprevalence surveys, human leukocyte antigen typing and high-throughput variant functional characterization assays. We analysed Lassa fever susceptibility and fatal outcomes in 533 cases of Lassa fever and 1,986 population controls recruited over a 7 year period in Nigeria and Sierra Leone. We detected genome-wide significant variant associations with Lassa fever fatal outcomes near GRM7 and LIF in the Nigerian cohort. We also show that a haplotype bearing signatures of positive selection and overlapping LARGE1, a required LASV entry factor, is associated with decreased risk of Lassa fever in the Nigerian cohort but not in the Sierra Leone cohort. Overall, we identified variants and genes that may impact the risk of severe Lassa fever, demonstrating how GWAS can provide insight into viral pathogenesis.


Asunto(s)
Fiebre de Lassa , Humanos , Fiebre de Lassa/genética , Fiebre de Lassa/diagnóstico , Fiebre de Lassa/epidemiología , Estudio de Asociación del Genoma Completo , Estudios Seroepidemiológicos , Virus Lassa/genética , Fiebre , Genética Humana
3.
Front Cell Infect Microbiol ; 14: 1341891, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38404292

RESUMEN

Lassa virus (LASV) causes an acute multisystemic hemorrhagic fever in humans known as Lassa fever, which is endemic in several African countries. This manuscript focuses on the progression of disease in cynomolgus macaques challenged with aerosolized LASV and serially sampled for the development and progression of gross and histopathologic lesions. Gross lesions were first noted in tissues on day 6 and persisted throughout day 12. Viremia and histologic lesions were first noted on day 6 commencing with the pulmonary system and hemolymphatic system and progressing at later time points to include all systems. Immunoreactivity to LASV antigen was first observed in the lungs of one macaque on day 3 and appeared localized to macrophages with an increase at later time points to include immunoreactivity in all organ systems. Additionally, this manuscript will serve as a detailed atlas of histopathologic lesions and disease progression for comparison to other animal models of aerosolized Arenaviral disease.


Asunto(s)
Fiebre de Lassa , Virus Lassa , Humanos , Animales , Fiebre de Lassa/patología , Macaca fascicularis , Antígenos Virales , Viremia
4.
bioRxiv ; 2024 Feb 12.
Artículo en Inglés | MEDLINE | ID: mdl-38410448

RESUMEN

Infection with Sudan virus (SUDV) is characterized by an aggressive disease course with case fatality rates between 40-100% and no approved vaccines or therapeutics. SUDV causes sporadic outbreaks in sub-Saharan Africa, including a recent outbreak in Uganda which has resulted in over 100 confirmed cases in one month. Prior vaccine and therapeutic efforts have historically prioritized Ebola virus (EBOV), leading to a significant gap in available treatments. Two vaccines, Erbevo ® and Zabdeno ® /Mvabea ® , are licensed for use against EBOV but are ineffective against SUDV. Recombinant adenovirus vector vaccines have been shown to be safe and effective against filoviruses, but efficacy depends on having low seroprevalence to the vector in the target human population. For this reason, and because of an excellent safety and immunogenicity profile, ChAd3 was selected as a superior vaccine vector. Here, a ChAd3 vaccine expressing the SUDV glycoprotein (GP) was evaluated for immunogenicity and efficacy in nonhuman primates. We demonstrate that a single dose of ChAd3-SUDV confers acute and durable protection against lethal SUDV challenge with a strong correlation between the SUDV GP-specific antibody titers and survival outcome. Additionally, we show that a bivalent ChAd3 vaccine encoding the GP from both EBOV and SUDV protects against both parenteral and aerosol lethal SUDV challenge. Our data indicate that the ChAd3-SUDV vaccine is a suitable candidate for a prophylactic vaccination strategy in regions at high risk of filovirus outbreaks. One Sentence Summary: A single-dose of ChAd3 vaccine protected macaques from lethal challenge with Sudan virus (SUDV) by parenteral and aerosol routes of exposure.

5.
Protein Eng Des Sel ; 362023 01 21.
Artículo en Inglés | MEDLINE | ID: mdl-37561410

RESUMEN

Monoclonal antibody (mAb) therapies have rapidly become a powerful class of therapeutics with applications covering a diverse range of clinical indications. Though most widely used for the treatment of cancer, mAbs are also playing an increasing role in the defense of viral infections, most recently with palivizumab for prevention and treatment of severe RSV infections in neonatal and pediatric populations. In addition, during the COVID-19 pandemic, mAbs provided a bridge to the rollout of vaccines; however, their continued role as a therapeutic option for those at greatest risk of severe disease has become limited due to the emergence of neutralization resistant Omicron variants. Although there are many techniques for the identification of mAbs, including single B cell cloning and immunization of genetically engineered mice, the low cost, rapid throughput and technological simplicity of antibody phage display has led to its widespread adoption in mAb discovery efforts. Here we used our 27-billion-member naïve single-chain antibody (scFv) phage library to identify a panel of neutralizing anti-SARS-CoV-2 scFvs targeting diverse epitopes on the receptor binding domain (RBD). Although typically a routine process, we found that upon conversion to IgG, a number of our most potent clones failed to maintain their neutralization potency. Kinetic measurements confirmed similar affinity to the RBD; however, mechanistic studies provide evidence that the loss of neutralization is a result of structural limitations likely arising from initial choice of panning antigen. Thus this work highlights a risk of scFv-phage panning to mAb conversion and the importance of initial antigen selection.


Asunto(s)
COVID-19 , Anticuerpos de Cadena Única , Animales , Ratones , Humanos , Epítopos , Pandemias , SARS-CoV-2/genética , Anticuerpos Antivirales , Anticuerpos Monoclonales , Inmunoglobulina G , Glicoproteína de la Espiga del Coronavirus/genética , Anticuerpos Neutralizantes/química
6.
PLoS Negl Trop Dis ; 17(4): e0010384, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-37079637

RESUMEN

We describe the results of a prospective observational study of the clinical natural history of human monkeypox (mpox) virus (MPXV) infections at the remote L'Hopital General de Reference de Kole (Kole hospital), the rainforest of the Congo River basin of the Democratic Republic of the Congo (DRC) from March 2007 until August 2011. The research was conducted jointly by the Institute National de Recherche Biomedical (INRB) and the US Army Medical Research Institute of Infectious Diseases (USAMRIID). The Kole hospital was one of the two previous WHO Mpox study sites (1981-1986). The hospital is staffed by a Spanish Order of Catholic Nuns from La Congregation Des Soeurs Missionnaires Du Christ Jesus including two Spanish physicians, who were members of the Order as well, were part of the WHO study on human mpox. Of 244 patients admitted with a clinical diagnosis of MPXV infection, 216 were positive in both the Pan-Orthopox and MPXV specific PCR. The cardinal observations of these 216 patients are summarized in this report. There were three deaths (3/216) among these hospitalized patients; fetal death occurred in 3 of 4 patients who were pregnant at admission, with the placenta of one fetus demonstrating prominent MPXV infection of the chorionic villi. The most common complaints were rash (96.8%), malaise (85.2%), sore throat (78.2%), and lymphadenopathy/adenopathy (57.4%). The most common physical exam findings were mpox rash (99.5%) and lymphadenopathy (98.6%). The single patient without the classic mpox rash had been previously vaccinated against smallpox. Age group of less than 5 years had the highest lesion count. Primary household cases tended to have higher lesion counts than secondary or later same household cases. Of the 216 patients, 200 were tested for IgM & IgG antibodies (Abs) to Orthopoxviruses. All 200 patients had anti-orthopoxvirus IgG Abs; whereas 189/200 were positive for IgM. Patients with hypoalbuminemia had a high risk of severe disease. Patients with fatal disease had higher maximum geometric mean values than survivors for the following variables, respectively: viral DNA in blood (DNAemia); maximum lesion count; day of admission mean AST and ALT.


Asunto(s)
Exantema , Humanos , Femenino , Embarazo , Preescolar , República Democrática del Congo/epidemiología , Placenta , Inmunoglobulina G , Inmunoglobulina M , Virus de la Viruela de los Monos/genética
7.
Cell Genom ; 3(12): 100440, 2023 Dec 13.
Artículo en Inglés | MEDLINE | ID: mdl-38169842

RESUMEN

Ebola virus (EBOV) causes Ebola virus disease (EVD), marked by severe hemorrhagic fever; however, the mechanisms underlying the disease remain unclear. To assess the molecular basis of EVD across time, we performed RNA sequencing on 17 tissues from a natural history study of 21 rhesus monkeys, developing new methods to characterize host-pathogen dynamics. We identified alterations in host gene expression with previously unknown tissue-specific changes, including downregulation of genes related to tissue connectivity. EBOV was widely disseminated throughout the body; using a new, broadly applicable deconvolution method, we found that viral load correlated with increased monocyte presence. Patterns of viral variation between tissues differentiated primary infections from compartmentalized infections, and several variants impacted viral fitness in a EBOV/Kikwit minigenome system, suggesting that functionally significant variants can emerge during early infection. This comprehensive portrait of host-pathogen dynamics in EVD illuminates new features of pathogenesis and establishes resources to study other emerging pathogens.


Asunto(s)
Ebolavirus , Fiebre Hemorrágica Ebola , Fiebres Hemorrágicas Virales , Animales , Fiebre Hemorrágica Ebola/patología , Macaca mulatta , Ebolavirus/genética
8.
Sci Transl Med ; 14(675): eabq6364, 2022 12 14.
Artículo en Inglés | MEDLINE | ID: mdl-36516269

RESUMEN

Marburg virus (MARV) causes a severe hemorrhagic fever disease in primates with mortality rates in humans of up to 90%. MARV has been identified as a category A bioterrorism agent by the Centers for Disease Control and Prevention (CDC) and priority pathogen A by the National Institute of Allergy and Infectious Diseases (NIAID), needing urgent research and development of countermeasures because of the high public health risk it poses. The recent cases of MARV in West Africa underscore the substantial outbreak potential of this virus. The potential for cross-border spread, as had occurred during the 2014-2016 Ebola virus outbreak, illustrates the critical need for MARV vaccines. To support regulatory approval of the chimpanzee adenovirus 3 (ChAd3)-MARV vaccine that has completed phase 1 trials, we showed that the nonreplicating ChAd3 vector, which has a demonstrated safety profile in humans, protected against a uniformly lethal challenge with MARV/Ang. Protective immunity was achieved within 7 days of vaccination and was maintained through 1 year after vaccination. Antigen-specific antibodies were an immune correlate of protection in the acute challenge model, and their concentration was predictive of protection. These results demonstrate that a single-shot ChAd3-MARV vaccine generated a protective immune response that was both rapid and durable with an immune correlate of protection that will support advanced clinical development.


Asunto(s)
Vacunas contra el Virus del Ébola , Ebolavirus , Fiebre Hemorrágica Ebola , Enfermedad del Virus de Marburg , Marburgvirus , Animales , Humanos , Pan troglodytes , Primates , Adenoviridae , Enfermedad del Virus de Marburg/prevención & control
9.
Nat Commun ; 13(1): 5814, 2022 10 03.
Artículo en Inglés | MEDLINE | ID: mdl-36192374

RESUMEN

Monoclonal antibodies are a promising approach to treat COVID-19, however the emergence of SARS-CoV-2 variants has challenged the efficacy and future of these therapies. Antibody cocktails are being employed to mitigate these challenges, but neutralization escape remains a major challenge and alternative strategies are needed. Here we present two anti-SARS-CoV-2 spike binding antibodies, one Class 1 and one Class 4, selected from our non-immune human single-chain variable fragment (scFv) phage library, that are engineered into four, fully-human IgG-like bispecific antibodies (BsAb). Prophylaxis of hACE2 mice and post-infection treatment of golden hamsters demonstrates the efficacy of the monospecific antibodies against the original Wuhan strain, while promising in vitro results with the BsAbs demonstrate enhanced binding and distinct synergistic effects on neutralizing activity against circulating variants of concern. In particular, one BsAb engineered in a tandem scFv-Fc configuration shows synergistic neutralization activity against several variants of concern including B.1.617.2. This work provides evidence that synergistic neutralization can be achieved using a BsAb scaffold, and serves as a foundation for the future development of broadly reactive BsAbs against emerging variants of concern.


Asunto(s)
Anticuerpos Biespecíficos , COVID-19 , Anticuerpos de Cadena Única , Animales , Anticuerpos Biespecíficos/genética , Anticuerpos Monoclonales , Anticuerpos Neutralizantes , Anticuerpos Antivirales/uso terapéutico , Cricetinae , Humanos , Inmunoglobulina G/genética , Ratones , Pruebas de Neutralización , SARS-CoV-2/genética , Anticuerpos de Cadena Única/genética , Glicoproteína de la Espiga del Coronavirus/genética
11.
Sci Immunol ; 7(75): eabl9943, 2022 09 09.
Artículo en Inglés | MEDLINE | ID: mdl-35771946

RESUMEN

Monoclonal antibodies are an efficacious therapy against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). However, rapid viral mutagenesis led to escape from most of these therapies, outlining the need for an antibody cocktail with a broad neutralizing potency. Using an unbiased interrogation of the memory B cell repertoire of patients with convalescent COVID-19, we identified human antibodies with broad antiviral activity in vitro and efficacy in vivo against all tested SARS-CoV-2 variants of concern, including Delta and Omicron BA.1 and BA.2. Here, we describe an antibody cocktail, IMM-BCP-01, that consists of three patient-derived broadly neutralizing antibodies directed at nonoverlapping surfaces on the SARS-CoV-2 Spike protein. Two antibodies, IMM20184 and IMM20190, directly blocked Spike binding to the ACE2 receptor. Binding of the third antibody, IMM20253, to its cryptic epitope on the outer surface of RBD altered the conformation of the Spike Trimer, promoting the release of Spike monomers. These antibodies decreased Omicron SARS-CoV-2 infection in the lungs of Syrian golden hamsters in vivo and potently induced antiviral effector response in vitro, including phagocytosis, ADCC, and complement pathway activation. Our preclinical data demonstrated that the three-antibody cocktail IMM-BCP-01 could be a promising means for preventing or treating infection of SARS-CoV-2 variants of concern, including Omicron BA.1 and BA.2, in susceptible individuals.


Asunto(s)
COVID-19 , SARS-CoV-2 , Animales , Anticuerpos Antivirales , Cricetinae , Humanos , Glicoproteína de la Espiga del Coronavirus/genética
12.
PLoS One ; 17(2): e0263834, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35143571

RESUMEN

Disease associated with Nipah virus infection causes a devastating and often fatal spectrum of syndromes predominated by both respiratory and neurologic conditions. Additionally, neurologic sequelae may manifest months to years later after virus exposure or apparent recovery. In the two decades since this disease emerged, much work has been completed in an attempt to understand the pathogenesis and facilitate development of medical countermeasures. Here we provide detailed organ system-specific pathologic findings following exposure of four African green monkeys to 2.41×105 pfu of the Malaysian strain of Nipah virus. Our results further substantiate the African green monkey as a model of human Nipah virus disease, by demonstrating both the respiratory and neurologic components of disease. Additionally, we demonstrate that a chronic phase of disease exists in this model, that may provide an important opportunity to study the enigmatic late onset and relapse encephalitis as it is described in human disease.


Asunto(s)
Encefalitis Viral/patología , Infecciones por Henipavirus/patología , Enfermedades Pulmonares/virología , Virus Nipah/patogenicidad , Animales , Chlorocebus aethiops , Modelos Animales de Enfermedad , Enfermedades Pulmonares/patología , Malasia , Masculino , Virus Nipah/clasificación
13.
Clin Infect Dis ; 74(6): 1081-1084, 2022 03 23.
Artículo en Inglés | MEDLINE | ID: mdl-34245255

RESUMEN

The clinical significance of severe acute respiratory syndrome coronavirus 2 (SARS CoV-2) RNA in stool remains uncertain. We found that extrapulmonary dissemination of infection to the gastrointestinal tract, assessed by the presence of SARS-CoV-2 RNA in stool, is associated with decreased coronavirus disease 2019 (COVID-19) survival. Measurement of SARS-CoV-2 RNA in stool may have utility for clinical risk assessment.


Asunto(s)
COVID-19 , SARS-CoV-2 , Heces , Tracto Gastrointestinal , Humanos , ARN Viral , SARS-CoV-2/genética
14.
Viruses ; 13(11)2021 11 17.
Artículo en Inglés | MEDLINE | ID: mdl-34835103

RESUMEN

Ebola virus disease (EVD) is a serious global health concern because case fatality rates are approximately 50% due to recent widespread outbreaks in Africa. Well-defined nonhuman primate (NHP) models for different routes of Ebola virus exposure are needed to test the efficacy of candidate countermeasures. In this natural history study, four rhesus macaques were challenged via aerosol with a target titer of 1000 plaque-forming units per milliliter of Ebola virus. The course of disease was split into the following stages for descriptive purposes: subclinical, clinical, and decompensated. During the subclinical stage, high levels of venous partial pressure of carbon dioxide led to respiratory acidemia in three of four of the NHPs, and all developed lymphopenia. During the clinical stage, all animals had fever, viremia, and respiratory alkalosis. The decompensatory stage involved coagulopathy, cytokine storm, and liver and renal injury. These events were followed by hypotension, elevated lactate, metabolic acidemia, shock and mortality similar to historic intramuscular challenge studies. Viral loads in the lungs of aerosol-exposed animals were not distinctly different compared to previous intramuscularly challenged studies. Differences in the aerosol model, compared to intramuscular model, include an extended subclinical stage, shortened clinical stage, and general decompensated stage. Therefore, the shortened timeframe for clinical detection of the aerosol-induced disease can impair timely therapeutic administration. In summary, this nonhuman primate model of aerosol-induced EVD characterizes early disease markers and additional details to enable countermeasure development.


Asunto(s)
Modelos Animales de Enfermedad , Ebolavirus/patogenicidad , Fiebre Hemorrágica Ebola/etiología , Aerosoles , Animales , Femenino , Fiebre Hemorrágica Ebola/inmunología , Fiebre Hemorrágica Ebola/patología , Fiebre Hemorrágica Ebola/virología , Macaca mulatta , Masculino , ARN Viral/sangre , Carga Viral
15.
Adv Healthc Mater ; 10(22): e2101370, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-34605223

RESUMEN

The coronavirus disease 2019 (COVID-19) pandemic demonstrates the importance of generating safe and efficacious vaccines that can be rapidly deployed against emerging pathogens. Subunit vaccines are considered among the safest, but proteins used in these typically lack strong immunogenicity, leading to poor immune responses. Here, a biomaterial COVID-19 vaccine based on a mesoporous silica rods (MSRs) platform is described. MSRs loaded with granulocyte-macrophage colony-stimulating factor (GM-CSF), the toll-like receptor 4 (TLR-4) agonist monophosphoryl lipid A (MPLA), and SARS-CoV-2 viral protein antigens slowly release their cargo and form subcutaneous scaffolds that locally recruit and activate antigen-presenting cells (APCs) for the generation of adaptive immunity. MSR-based vaccines generate robust and durable cellular and humoral responses against SARS-CoV-2 antigens, including the poorly immunogenic receptor binding domain (RBD) of the spike (S) protein. Persistent antibodies over the course of 8 months are found in all vaccine configurations tested and robust in vitro viral neutralization is observed both in a prime-boost and a single-dose regimen. These vaccines can be fully formulated ahead of time or stored lyophilized and reconstituted with an antigen mixture moments before injection, which can facilitate its rapid deployment against emerging SARS-CoV-2 variants or new pathogens. Together, the data show a promising COVID-19 vaccine candidate and a generally adaptable vaccine platform against infectious pathogens.


Asunto(s)
COVID-19 , SARS-CoV-2 , Inmunidad Adaptativa , Anticuerpos Antivirales , Materiales Biocompatibles , Vacunas contra la COVID-19 , Humanos
16.
J Am Chem Soc ; 143(42): 17615-17621, 2021 10 27.
Artículo en Inglés | MEDLINE | ID: mdl-34647745

RESUMEN

Cellular binding and entry of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) are mediated by its spike glycoprotein (S protein), which binds with not only the human angiotensin-converting enzyme 2 (ACE2) receptor but also glycosaminoglycans such as heparin. Cell membrane-coated nanoparticles ("cellular nanosponges") mimic the host cells to attract and neutralize SARS-CoV-2 through natural cellular receptors, leading to a broad-spectrum antiviral strategy. Herein, we show that increasing surface heparin density on the cellular nanosponges can promote their inhibition against SARS-CoV-2. Specifically, cellular nanosponges are made with azido-expressing host cell membranes followed by conjugating heparin to the nanosponge surfaces. Cellular nanosponges with a higher heparin density have a larger binding capacity with viral S proteins and a significantly higher inhibition efficacy against SARS-CoV-2 infectivity. Overall, surface glycan engineering of host-mimicking cellular nanosponges is a facile method to enhance SARS-CoV-2 inhibition. This approach can be readily generalized to promote the inhibition of other glycan-dependent viruses.


Asunto(s)
Tratamiento Farmacológico de COVID-19 , Heparina/administración & dosificación , Nanoestructuras/uso terapéutico , Polisacáridos/administración & dosificación , SARS-CoV-2/metabolismo , COVID-19/virología , Heparina/metabolismo , Humanos , Polisacáridos/metabolismo
17.
Front Physiol ; 12: 691074, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34552498

RESUMEN

Background and Objectives: Early warning of bacterial and viral infection, prior to the development of overt clinical symptoms, allows not only for improved patient care and outcomes but also enables faster implementation of public health measures (patient isolation and contact tracing). Our primary objectives in this effort are 3-fold. First, we seek to determine the upper limits of early warning detection through physiological measurements. Second, we investigate whether the detected physiological response is specific to the pathogen. Third, we explore the feasibility of extending early warning detection with wearable devices. Research Methods: For the first objective, we developed a supervised random forest algorithm to detect pathogen exposure in the asymptomatic period prior to overt symptoms (fever). We used high-resolution physiological telemetry data (aortic blood pressure, intrathoracic pressure, electrocardiograms, and core temperature) from non-human primate animal models exposed to two viral pathogens: Ebola and Marburg (N = 20). Second, to determine reusability across different pathogens, we evaluated our algorithm against three independent physiological datasets from non-human primate models (N = 13) exposed to three different pathogens: Lassa and Nipah viruses and Y. pestis. For the third objective, we evaluated performance degradation when the algorithm was restricted to features derived from electrocardiogram (ECG) waveforms to emulate data from a non-invasive wearable device. Results: First, our cross-validated random forest classifier provides a mean early warning of 51 ± 12 h, with an area under the receiver-operating characteristic curve (AUC) of 0.93 ± 0.01. Second, our algorithm achieved comparable performance when applied to datasets from different pathogen exposures - a mean early warning of 51 ± 14 h and AUC of 0.95 ± 0.01. Last, with a degraded feature set derived solely from ECG, we observed minimal degradation - a mean early warning of 46 ± 14 h and AUC of 0.91 ± 0.001. Conclusion: Under controlled experimental conditions, physiological measurements can provide over 2 days of early warning with high AUC. Deviations in physiological signals following exposure to a pathogen are due to the underlying host's immunological response and are not specific to the pathogen. Pre-symptomatic detection is strong even when features are limited to ECG-derivatives, suggesting that this approach may translate to non-invasive wearable devices.

18.
Cell ; 184(19): 4969-4980.e15, 2021 09 16.
Artículo en Inglés | MEDLINE | ID: mdl-34332650

RESUMEN

Memory B cell reserves can generate protective antibodies against repeated SARS-CoV-2 infections, but with unknown reach from original infection to antigenically drifted variants. We charted memory B cell receptor-encoded antibodies from 19 COVID-19 convalescent subjects against SARS-CoV-2 spike (S) and found seven major antibody competition groups against epitopes recurrently targeted across individuals. Inclusion of published and newly determined structures of antibody-S complexes identified corresponding epitopic regions. Group assignment correlated with cross-CoV-reactivity breadth, neutralization potency, and convergent antibody signatures. Although emerging SARS-CoV-2 variants of concern escaped binding by many members of the groups associated with the most potent neutralizing activity, some antibodies in each of those groups retained affinity-suggesting that otherwise redundant components of a primary immune response are important for durable protection from evolving pathogens. Our results furnish a global atlas of S-specific memory B cell repertoires and illustrate properties driving viral escape and conferring robustness against emerging variants.

19.
Cell Host Microbe ; 29(9): 1437-1453.e8, 2021 09 08.
Artículo en Inglés | MEDLINE | ID: mdl-34428428

RESUMEN

The SARS-CoV-2 pandemic has affected more than 185 million people worldwide resulting in over 4 million deaths. To contain the pandemic, there is a continued need for safe vaccines that provide durable protection at low and scalable doses and can be deployed easily. Here, AAVCOVID-1, an adeno-associated viral (AAV), spike-gene-based vaccine candidate demonstrates potent immunogenicity in mouse and non-human primates following a single injection and confers complete protection from SARS-CoV-2 challenge in macaques. Peak neutralizing antibody titers are sustained at 1 year and complemented by functional memory T cell responses. The AAVCOVID vector has no relevant pre-existing immunity in humans and does not elicit cross-reactivity to common AAVs used in gene therapy. Vector genome persistence and expression wanes following injection. The single low-dose requirement, high-yield manufacturability, and 1-month stability for storage at room temperature may make this technology well suited to support effective immunization campaigns for emerging pathogens on a global scale.


Asunto(s)
Anticuerpos Neutralizantes/sangre , Anticuerpos Antivirales/sangre , Vacunas contra la COVID-19/inmunología , COVID-19/prevención & control , SARS-CoV-2/inmunología , Glicoproteína de la Espiga del Coronavirus/inmunología , Animales , Anticuerpos Neutralizantes/inmunología , Anticuerpos Antivirales/inmunología , Vacunas contra la COVID-19/administración & dosificación , Vacunas contra la COVID-19/genética , Dependovirus/genética , Dependovirus/metabolismo , Femenino , Humanos , Inmunogenicidad Vacunal/inmunología , Memoria Inmunológica/inmunología , Macaca fascicularis , Macaca mulatta , Masculino , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos C57BL , Linfocitos T/inmunología , Transgenes/genética , Vacunación/métodos , Carga Viral/inmunología
20.
JCI Insight ; 6(1)2021 01 11.
Artículo en Inglés | MEDLINE | ID: mdl-33427208

RESUMEN

The rapid spread of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), coupled with a lack of therapeutics, has paralyzed the globe. Although significant effort has been invested in identifying antibodies that block infection, the ability of antibodies to target infected cells through Fc interactions may be vital to eliminate the virus. To explore the role of Fc activity in SARS-CoV-2 immunity, the functional potential of a cross-SARS-reactive antibody, CR3022, was assessed. CR3022 was able to broadly drive antibody effector functions, providing critical immune clearance at entry and upon egress. Using selectively engineered Fc variants, no protection was observed after administration of WT IgG1 in mice or hamsters. Conversely, the functionally enhanced Fc variant resulted in increased pathology in both the mouse and hamster models, causing weight loss in mice and enhanced viral replication and weight loss in the more susceptible hamster model, highlighting the pathological functions of Fc-enhancing mutations. These data point to the critical need for strategic Fc engineering for the treatment of SARS-CoV-2 infection.


Asunto(s)
Anticuerpos Neutralizantes/farmacología , COVID-19/inmunología , Inmunidad Innata/efectos de los fármacos , Fragmentos Fc de Inmunoglobulinas/genética , Inmunoglobulina G/farmacología , SARS-CoV-2/efectos de los fármacos , Replicación Viral/efectos de los fármacos , Animales , Anticuerpos Monoclonales , Anticuerpos Neutralizantes/genética , Anticuerpos Neutralizantes/uso terapéutico , COVID-19/fisiopatología , Cricetinae , Reacciones Cruzadas , Epítopos , Humanos , Inmunidad Innata/inmunología , Inmunoglobulina G/genética , Inmunoglobulina G/uso terapéutico , Mesocricetus , Ratones , Coronavirus del Síndrome Respiratorio de Oriente Medio/efectos de los fármacos , Coronavirus del Síndrome Respiratorio de Oriente Medio/inmunología , Ingeniería de Proteínas , Receptores Fc/inmunología , Coronavirus Relacionado al Síndrome Respiratorio Agudo Severo/efectos de los fármacos , Coronavirus Relacionado al Síndrome Respiratorio Agudo Severo/inmunología , SARS-CoV-2/inmunología , Índice de Severidad de la Enfermedad , Glicoproteína de la Espiga del Coronavirus/inmunología , Células THP-1 , Carga Viral/efectos de los fármacos , Pérdida de Peso/efectos de los fármacos , Tratamiento Farmacológico de COVID-19
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