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1.
Phys Med Biol ; 67(18)2022 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-36097336

RESUMO

Objective. To develop a new model (Mayo Clinic Florida microdosimetric kinetic model, MCF MKM) capable of accurately describing thein vitroclonogenic survival at low and high linear energy transfer (LET) using single-event microdosimetric spectra in a single target.Methodology. The MCF MKM is based on the 'post-processing average' implementation of the non-Poisson microdosimetric kinetic model and includes a novel expression to compute the particle-specific quadratic-dependence of the cell survival with respect to dose (ßof the linear-quadratic model). A new methodology toa prioricalculate the mean radius of the MCF MKM subnuclear domains is also introduced. Lineal energy spectra were simulated with the Particle and Heavy Ion Transport code System (PHITS) for1H,4He,12C,20Ne,40Ar,56Fe, and132Xe ions and used in combination with the MCF MKM to calculate the ion-specific LET-dependence of the relative biological effectiveness (RBE) for Chinese hamster lung fibroblasts (V79 cell line) and human salivary gland tumor cells (HSG cell line). The results were compared within vitrodata from the Particle Irradiation Data Ensemble (PIDE) andin silicoresults of different models. The possibility of performing experiment-specific predictions to explain the scatter in thein vitroRBE data was also investigated. Finally, a sensitivity analysis on the model parameters is also included.Main results. The RBE values predicted with the MCF MKM were found to be in good agreement with thein vitrodata for all tested conditions. Though all MCF MKM model parameters were determineda priori, the accuracy of the MCF MKM was found to be comparable or superior to that of other models. The model parameters determineda prioriwere in good agreement with the ones obtained by fitting all availablein vitrodata.Significance. The MCF MKM will be considered for implementation in cancer radiotherapy treatment planning with accelerated ions.


Assuntos
Benchmarking , Transferência Linear de Energia , Animais , Cricetinae , Cricetulus , Florida , Humanos , Cinética , Eficiência Biológica Relativa
2.
PLoS Pathog ; 18(9): e1010807, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36067210

RESUMO

Understanding the host pathways that define susceptibility to Severe-acute-respiratory-syndrome-coronavirus-2 (SARS-CoV-2) infection and disease are essential for the design of new therapies. Oxygen levels in the microenvironment define the transcriptional landscape, however the influence of hypoxia on virus replication and disease in animal models is not well understood. In this study, we identify a role for the hypoxic inducible factor (HIF) signalling axis to inhibit SARS-CoV-2 infection, epithelial damage and respiratory symptoms in the Syrian hamster model. Pharmacological activation of HIF with the prolyl-hydroxylase inhibitor FG-4592 significantly reduced infectious virus in the upper and lower respiratory tract. Nasal and lung epithelia showed a reduction in SARS-CoV-2 RNA and nucleocapsid expression in treated animals. Transcriptomic and pathological analysis showed reduced epithelial damage and increased expression of ciliated cells. Our study provides new insights on the intrinsic antiviral properties of the HIF signalling pathway in SARS-CoV-2 replication that may be applicable to other respiratory pathogens and identifies new therapeutic opportunities.


Assuntos
COVID-19 , Inibidores de Prolil-Hidrolase , Animais , Antivirais , Cricetinae , Hipóxia , Pulmão/patologia , Mesocricetus , Oxigênio , RNA Viral , SARS-CoV-2
3.
Pharmacol Res Perspect ; 10(5): e01003, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-36101495

RESUMO

α2-adrenoceptors, (α2A, α2B and α2C-subtypes), are Gi-coupled receptors. Central activation of brain α2A and α2C-adrenoceptors is the main site for α2-agonist mediated clinical responses in hypertension, ADHD, muscle spasm and ITU management of sedation, reduction in opiate requirements, nausea and delirium. However, despite having the same Gi-potency in functional assays, some α2-agonists also stimulate Gs-responses whilst others do not. This was investigated. Agonist responses to 49 different α-agonists were studied (CRE-gene transcription, cAMP, ERK1/2-phosphorylation and binding affinity) in CHO cells stably expressing the human α2A, α2B or α2C-adrenoceptor, enabling ligand intrinsic efficacy to be determined (binding KD /Gi-IC50 ). Ligands with high intrinsic efficacy (e.g., brimonidine and moxonidine at α2A) stimulated biphasic (Gi-Gs) concentration responses, however for ligands with low intrinsic efficacy (e.g., naphazoline), responses were monophasic (Gi-only). ERK1/2-phosphorylation responses appeared to be Gi-mediated. For Gs-mediated responses to be observed, both a system with high receptor reserve and high agonist intrinsic efficacy were required. From the Gi-mediated efficacy ratio, the degree of Gs-coupling could be predicted. The clinical relevance and precise receptor conformational changes that occur, given the structural diversity of compounds with high intrinsic efficacy, remains to be determined. Comparison with α1 and ß1/ß2-adrenoceptors demonstrated subclass affinity selectivity for some compounds (e.g., α2:dexmedetomidine, α1:A61603) whilst e.g., oxymetazoline had high affinity for both α2A and α1A-subtypes, compared to all others. Some compounds had subclass selectivity due to selective intrinsic efficacy (e.g., α2:brimonidine, α1:methoxamine/etilefrine). A detailed knowledge of these agonist characteristics is vital for improving computer-based deep-learning and drug design.


Assuntos
Ligantes , Animais , Tartarato de Brimonidina , Células CHO , Cricetinae , Cricetulus , Humanos
4.
Front Immunol ; 13: 999470, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36110841

RESUMO

Interleukin-10 (IL-10) is a widely recognized immunosuppressive factor. Although the concept that IL-10 executes an anti-inflammatory role is accepted, the relationship between IL-10 and atherosclerosis is still unclear, thus limiting the application of IL-10-based therapies for this disease. Emerging evidence suggests that IL-10 also plays a key role in energy metabolism and regulation of gut microbiota; however, whether IL-10 can affect atherosclerotic lesion development by integrating lipid and tissue homeostasis has not been investigated. In the present study, we developed a human-like hamster model deficient in IL-10 using CRISPR/Cas9 technology. Our results showed that loss of IL-10 changed the gut microbiota in hamsters on chow diet, leading to an increase in lipopolysaccharide (LPS) production and elevated concentration of LPS in plasma. These changes were associated with systemic inflammation, lipodystrophy, and dyslipidemia. Upon high cholesterol/high fat diet feeding, IL-10-deficient hamsters exhibited abnormal distribution of triglyceride and cholesterol in lipoprotein particles, impaired lipid transport in macrophages and aggravated atherosclerosis. These findings show that silencing IL-10 signaling in hamsters promotes atherosclerosis by affecting lipid and tissue homeostasis through a gut microbiota/adipose tissue/liver axis.


Assuntos
Aterosclerose , Interleucina-10 , Animais , Aterosclerose/genética , Aterosclerose/metabolismo , Sistemas CRISPR-Cas , Colesterol/metabolismo , Cricetinae , Dieta Hiperlipídica/efeitos adversos , Homeostase , Humanos , Interleucina-10/genética , Interleucina-10/metabolismo , Lipopolissacarídeos , Lipoproteínas/metabolismo , Triglicerídeos
5.
Sci Rep ; 12(1): 15517, 2022 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-36109550

RESUMO

Coronavirus disease 2019 (COVID-19) continues to significantly impact the global population, thus countermeasure platforms that enable rapid development of therapeutics against variants of SARS-CoV-2 are essential. We report use of a phage display human antibody library approach to rapidly identify neutralizing antibodies (nAbs) against SARS-CoV-2. We demonstrate the binding and neutralization capability of two nAbs, STI-2020 and STI-5041, against the SARS-CoV-2 WA-1 strain as well as the Alpha and Beta variants. STI-2020 and STI-5041 were protective when administered intravenously or intranasally in the golden (Syrian) hamster model of COVID-19 challenged with the WA-1 strain or Beta variant. The ability to administer nAbs intravenously and intranasally may have important therapeutic implications and Phase 1 healthy subjects clinical trials are ongoing.


Assuntos
COVID-19 , Animais , Anticorpos Monoclonais , Anticorpos Neutralizantes/uso terapêutico , Anticorpos Antivirais/uso terapêutico , Cricetinae , Humanos , Mesocricetus , Testes de Neutralização , SARS-CoV-2
6.
Sci Rep ; 12(1): 15069, 2022 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-36064749

RESUMO

Golden Syrian hamsters (Mesocricetus auratus) are used as a research model for severe acute respiratory syndrome coronavirus type 2 (SARS-CoV-2). Millions of Golden Syrian hamsters are also kept as pets in close contact to humans. To determine the minimum infective dose (MID) for assessing the zoonotic transmission risk, and to define the optimal infection dose for experimental studies, we orotracheally inoculated hamsters with SARS-CoV-2 doses from 1 * 105 to 1 * 10-4 tissue culture infectious dose 50 (TCID50). Body weight and virus shedding were monitored daily. 1 * 10-3 TCID50 was defined as the MID, and this was still sufficient to induce virus shedding at levels up to 102.75 TCID50/ml, equaling the estimated MID for humans. Virological and histological data revealed 1 * 102 TCID50 as the optimal dose for experimental infections. This compelling high susceptibility leading to productive infections in Golden Syrian hamsters must be considered as a potential source of SARS-CoV-2 infection for humans that come into close contact with pet hamsters.


Assuntos
COVID-19 , SARS-CoV-2 , Animais , Cricetinae , Modelos Animais de Doenças , Humanos , Pulmão/patologia , Mesocricetus , Pandemias , Zoonoses/patologia
7.
J Egypt Natl Canc Inst ; 34(1): 37, 2022 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-36058937

RESUMO

BACKGROUND: About 7 million people die from various types of cancer every year representing nearly 12.5% of deaths worldwide. This fact raises the demand to develop new, effective anticancer, onco-suppressive, and chemoprotective agents for the future fighting of cancers. Genistein exhibits pleiotropic functions in cancer, metabolism, and inflammation. It functions as an antineoplastic agent through its effect on the cell cycle, apoptotic processes, angiogenesis, invasion, and metastasis. AIM OF THE STUDY: The current study aimed to study the genistein onco-suppressive effects during 7,12-dimethylbenz[a]anthracene (DMBA)-induced oral carcinogenesis in hamsters' buccal pouch utilizing flow cytometry analysis (FMA), as a fast-diagnosing tool, in addition to the histopathology. MATERIAL AND METHODS: The buccal mucosa of adult male Syrian hamsters was painted with paraffin oil only (group 1), DMBA mixed in mineral oil (group 2), or orally administrated genistein along with painting DMBA (group 2B). The buccal mucosa was utilized for flow cytometric analysis and histopathological examination. RESULTS: Grossly, DMBA-induced carcinogenesis started at the 9th week. Progressive signs appeared in the following weeks reaching to large ulcerative oral masses and exophytic nodules at the 21st week. Histologically, invasive well-differentiated oral squamous cell carcinoma (OSCC) appeared in the underlying tissues from the 12th week, showing malignant criteria. Genistein had delayed clinicopathological change, which started 6 weeks later, than the DMBA-painted hamsters, as mild epithelial dysplastic changes. This became moderate during the last 6 weeks, without dysplastic changes. Flow cytometry revealed that DMBA led to considerable variation in DNA proliferation activity, aneuploid DNA pattern, in 47.22% of hamsters and significantly raised the S-phase fragment (SPF) values, which drastically reduced after genistein treatment. CONCLUSION: Taken together, genistein could be employed as an onco-suppressive agent for carcinogenesis. Moreover, FMA could be used as an aiding fast tool for diagnosis of cancer.


Assuntos
Carcinoma de Células Escamosas , Neoplasias de Cabeça e Pescoço , Neoplasias Bucais , 9,10-Dimetil-1,2-benzantraceno/toxicidade , Animais , Carcinogênese/patologia , Carcinoma de Células Escamosas/induzido quimicamente , Carcinoma de Células Escamosas/tratamento farmacológico , Carcinoma de Células Escamosas/patologia , Cricetinae , Genisteína/efeitos adversos , Humanos , Masculino , Mesocricetus , Neoplasias Bucais/induzido quimicamente , Neoplasias Bucais/tratamento farmacológico , Carcinoma de Células Escamosas de Cabeça e Pescoço
8.
PLoS Pathog ; 18(9): e1010741, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36070309

RESUMO

Severe Acute Respiratory Syndrome Coronavirus (SARS-CoV-2) can cause the life-threatening acute respiratory disease called COVID-19 (Coronavirus Disease 2019) as well as debilitating multiorgan dysfunction that persists after the initial viral phase has resolved. Long COVID or Post-Acute Sequelae of COVID-19 (PASC) is manifested by a variety of symptoms, including fatigue, dyspnea, arthralgia, myalgia, heart palpitations, and memory issues sometimes affecting between 30% and 75% of recovering COVID-19 patients. However, little is known about the mechanisms causing Long COVID and there are no widely accepted treatments or therapeutics. After introducing the clinical aspects of acute COVID-19 and Long COVID in humans, we summarize the work in animals (mice, Syrian hamsters, ferrets, and nonhuman primates (NHPs)) to model human COVID-19. The virology, pathology, immune responses, and multiorgan involvement are explored. Additionally, any studies investigating time points longer than 14 days post infection (pi) are highlighted for insight into possible long-term disease characteristics. Finally, we discuss how the models can be leveraged for treatment evaluation, including pharmacological agents that are currently in human clinical trials for treating Long COVID. The establishment of a recognized Long COVID preclinical model representing the human condition would allow the identification of mechanisms causing disease as well as serve as a vehicle for evaluating potential therapeutics.


Assuntos
COVID-19 , Animais , COVID-19/complicações , Cricetinae , Furões , Humanos , Mesocricetus , Camundongos , SARS-CoV-2
9.
Proc Biol Sci ; 289(1982): 20220668, 2022 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-36100021

RESUMO

Coordinating physiological and behavioural processes across the annual cycle is essential in enabling individuals to maximize fitness. While the mechanisms underlying seasonal reproduction and its associated behaviours are well characterized, fewer studies have examined the hormonal basis of non-reproductive social behaviours (e.g. aggression) on a seasonal time scale. Our previous work suggests that the pineal hormone melatonin facilitates a 'seasonal switch' in neuroendocrine regulation of aggression in male and female Siberian hamsters (Phodopus sungorus), specifically by acting on the adrenal glands to increase the production of the androgen dehydroepiandrosterone (DHEA) during the short-day (SD) photoperiods of the non-breeding season. Here, we provide evidence that the activity of 3ß-hydroxysteroid dehydrogenase/Δ5-Δ4 isomerase (3ß-HSD), a key enzyme within the steroidogenic pathway that mediates DHEA synthesis and metabolism, varies in a sex-specific and melatonin-dependent manner. Although both male and female hamsters displayed increased aggression in response to SDs and SD-like melatonin, only males showed an increase in adrenal 3ß-HSD activity. Conversely, SD and melatonin-treated females exhibited reductions in both adrenal and neural 3ß-HSD activity. Collectively, these results suggest a potential role for 3ß-HSD in modulating non-breeding aggression and, more broadly, demonstrate how distinct neuroendocrine mechanisms may underlie the same behavioural phenotype in males and females.


Assuntos
Melatonina , Phodopus , Agressão/fisiologia , Animais , Cricetinae , Desidroepiandrosterona/metabolismo , Feminino , Masculino , Melatonina/metabolismo , Phodopus/metabolismo , Estações do Ano
10.
Proc Natl Acad Sci U S A ; 119(39): e2204624119, 2022 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-36074824

RESUMO

The high transmissibility of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is a primary driver of the COVID-19 pandemic. While existing interventions prevent severe disease, they exhibit mixed efficacy in preventing transmission, presumably due to their limited antiviral effects in the respiratory mucosa, whereas interventions targeting the sites of viral replication might more effectively limit respiratory virus transmission. Recently, intranasally administered RNA-based therapeutic interfering particles (TIPs) were reported to suppress SARS-CoV-2 replication, exhibit a high barrier to resistance, and prevent serious disease in hamsters. Since TIPs intrinsically target the tissues with the highest viral replication burden (i.e., respiratory tissues for SARS-CoV-2), we tested the potential of TIP intervention to reduce SARS-CoV-2 shedding. Here, we report that a single, postexposure TIP dose lowers SARS-CoV-2 nasal shedding, and at 5 days postinfection, infectious virus shed is below detection limits in 4 out of 5 infected animals. Furthermore, TIPs reduce shedding of Delta variant or WA-1 from infected to uninfected hamsters. Cohoused "contact" animals exposed to infected, TIP-treated animals exhibited significantly lower viral loads, reduced inflammatory cytokines, no severe lung pathology, and shortened shedding duration compared to animals cohoused with untreated infected animals. TIPs may represent an effective countermeasure to limit SARS-CoV-2 transmission.


Assuntos
COVID-19 , RNA Mensageiro , RNA Interferente Pequeno , SARS-CoV-2 , Eliminação de Partículas Virais , Animais , COVID-19/terapia , COVID-19/transmissão , Cricetinae , RNA Mensageiro/administração & dosagem , RNA Interferente Pequeno/administração & dosagem , SARS-CoV-2/genética , SARS-CoV-2/fisiologia
11.
J Transl Med ; 20(1): 412, 2022 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-36076294

RESUMO

BACKGROUND: Berberine (BBR), an isoquinoline alkaloid isolated from Rhizoma Coptis, is widely used in the treatment of hyperlipidemia (HLP) in China. At present, the efficacy of BBR against HLP is relatively clear, but there are few researches on its mechanism. The purpose of this study was to evaluate the potentially beneficial role of BBR in HLP hamster models, as well as investigate its possible mechanisms and potential lipid biomarkers in combination with network pharmacology. METHODS: HLP hamster model was induced by high-fat diet. Hematoxylin-eosin (HE) staining was used to determine the degree of hepatic pathological injury. Liquid chromatography-mass spectrometry was used to analyze lipid metabolism profiles of liver samples, and multiple statistical analysis methods were used to screen and identify lipid biomarkers. The possible molecular mechanism was unraveled by network pharmacology. RESULTS: The results showed that 13 metabolites, including CE (16:1), HexCer (D18:1/19:0) and LPC (O-22:0) were biomarkers of BBR regulation. CHPT1, PLA2G4A, LCAT and UGCG were predicted as the lipid-linked targets of BBR against HLP, whilst glycerophospholipid and sphingolipid metabolism were the key pathways of BBR against HLP. CONCLUSIONS: In summary, this study provides new insights into the protective mechanism of BBR against HLP through network pharmacology and lipidomic approaches.


Assuntos
Berberina , Hiperlipidemias , Animais , Berberina/farmacologia , Berberina/uso terapêutico , Cricetinae , Humanos , Hiperlipidemias/tratamento farmacológico , Lipidômica , Lipídeos , Farmacologia em Rede
12.
Int J Mol Sci ; 23(17)2022 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-36077460

RESUMO

The neural cell adhesion molecule (NCAM) plays important functional roles in the developing and mature nervous systems. Here, we show that the transient receptor potential canonical (TRPC) ion channels TRPC1, -4, and -5 not only interact with the intracellular domains of the transmembrane isoforms NCAM140 and NCAM180, but also with the glycan polysialic acid (PSA) covalently attached to the NCAM protein backbone. NCAM antibody treatment leads to the opening of TRPC1, -4, and -5 hetero- or homomers at the plasma membrane and to the influx of Ca2+ into cultured cortical neurons and CHO cells expressing NCAM, PSA, and TRPC1 and -4 or TRPC1 and -5. NCAM-stimulated Ca2+ entry was blocked by the TRPC inhibitor Pico145 or the bacterial PSA homolog colominic acid. NCAM-stimulated Ca2+ influx was detectable neither in NCAM-deficient cortical neurons nor in TRPC1/4- or TRPC1/5-expressing CHO cells that express NCAM, but not PSA. NCAM-induced neurite outgrowth was reduced by TRPC inhibitors and a function-blocking TRPC1 antibody. A characteristic signaling feature was that extracellular signal-regulated kinase 1/2 phosphorylation was also reduced by TRPC inhibitors. Our findings indicate that the interaction of NCAM with TRPC1, -4, and -5 contributes to the NCAM-stimulated and PSA-dependent Ca2+ entry into neurons thereby influencing essential neural functions.


Assuntos
Moléculas de Adesão de Célula Nervosa , Canais de Cátion TRPC , Animais , Células CHO , Cricetinae , Cricetulus , Moléculas de Adesão de Célula Nervosa/metabolismo , Neurônios/metabolismo , Canais de Cátion TRPC/metabolismo
13.
Acta Neuropathol Commun ; 10(1): 124, 2022 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-36058935

RESUMO

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection is associated with various neurological complications. Although the mechanism is not fully understood, several studies have shown that neuroinflammation occurs in the acute and post-acute phase. As these studies have predominantly been performed with isolates from 2020, it is unknown if there are differences among SARS-CoV-2 variants in their ability to cause neuroinflammation. Here, we compared the neuroinvasiveness, neurotropism and neurovirulence of the SARS-CoV-2 ancestral strain D614G, the Delta (B.1.617.2) and Omicron BA.1 (B.1.1.529) variants using in vitro and in vivo models. The Omicron BA.1 variant showed reduced neurotropism and neurovirulence compared to Delta and D614G in human induced pluripotent stem cell (hiPSC)-derived cortical neurons co-cultured with astrocytes. Similar differences were obtained in Syrian hamsters inoculated with D614G, Delta and the Omicron BA.1 variant 5 days post infection. Replication in the olfactory mucosa was observed in all hamsters, but most prominently in D614G inoculated hamsters. Furthermore, neuroinvasion into the CNS via the olfactory nerve was observed in D614G, but not Delta or Omicron BA.1 inoculated hamsters. Furthermore, neuroinvasion was associated with neuroinflammation in the olfactory bulb of hamsters inoculated with D614G. Altogether, our findings suggest differences in the neuroinvasive, neurotropic and neurovirulent potential between SARS-CoV-2 variants using in vitro hiPSC-derived neural cultures and in vivo in hamsters during the acute phase of the infection.


Assuntos
COVID-19 , Células-Tronco Pluripotentes Induzidas , Animais , Cricetinae , Humanos , Mesocricetus , SARS-CoV-2
14.
Sci Transl Med ; 14(662): eabq1945, 2022 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-36103514

RESUMO

Emergence of SARS-CoV-2 variants of concern (VOCs), including the highly transmissible Omicron and Delta strains, has posed constant challenges to the current COVID-19 vaccines that principally target the viral spike protein (S). Here, we report a nucleoside-modified messenger RNA (mRNA) vaccine that expresses the more conserved viral nucleoprotein (mRNA-N) and show that mRNA-N vaccination alone can induce modest control of SARS-CoV-2. Critically, combining mRNA-N with the clinically proven S-expressing mRNA vaccine (mRNA-S+N) induced robust protection against both Delta and Omicron variants. In the hamster models of SARS-CoV-2 VOC challenge, we demonstrated that, compared to mRNA-S alone, combination mRNA-S+N vaccination not only induced more robust control of the Delta and Omicron variants in the lungs but also provided enhanced protection in the upper respiratory tract. In vivo CD8+ T cell depletion suggested a potential role for CD8+ T cells in protection conferred by mRNA-S+N vaccination. Antigen-specific immune analyses indicated that N-specific immunity, as well as augmented S-specific immunity, was associated with enhanced protection elicited by the combination mRNA vaccination. Our findings suggest that combined mRNA-S+N vaccination is an effective approach for promoting broad protection against SARS-CoV-2 variants.


Assuntos
COVID-19 , Vacinas Virais , Animais , Linfócitos T CD8-Positivos , COVID-19/prevenção & controle , Vacinas contra COVID-19 , Cricetinae , Humanos , Nucleocapsídeo , RNA Mensageiro/genética , SARS-CoV-2 , Vacinação , Vacinas Sintéticas , Proteínas Virais , Vacinas de mRNA
15.
Commun Biol ; 5(1): 933, 2022 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-36085335

RESUMO

Nanobodies offer several potential advantages over mAbs for the control of SARS-CoV-2. Their ability to access cryptic epitopes conserved across SARS-CoV-2 variants of concern (VoCs) and feasibility to engineer modular, multimeric designs, make these antibody fragments ideal candidates for developing broad-spectrum therapeutics against current and continually emerging SARS-CoV-2 VoCs. Here we describe a diverse collection of 37 anti-SARS-CoV-2 spike glycoprotein nanobodies extensively characterized as both monovalent and IgG Fc-fused bivalent modalities. The nanobodies were collectively shown to have high intrinsic affinity; high thermal, thermodynamic and aerosolization stability; broad subunit/domain specificity and cross-reactivity across existing VoCs; wide-ranging epitopic and mechanistic diversity and high and broad in vitro neutralization potencies. A select set of Fc-fused nanobodies showed high neutralization efficacies in hamster models of SARS-CoV-2 infection, reducing viral burden by up to six orders of magnitude to below detectable levels. In vivo protection was demonstrated with anti-RBD and previously unreported anti-NTD and anti-S2 nanobodies. This collection of nanobodies provides a potential therapeutic toolbox from which various cocktails or multi-paratopic formats could be built to combat multiple SARS-CoV-2 variants.


Assuntos
COVID-19 , Anticorpos de Domínio Único , Animais , Anticorpos Monoclonais , Cricetinae , Humanos , SARS-CoV-2/genética , Anticorpos de Domínio Único/genética
16.
EBioMedicine ; 83: 104196, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35932641

RESUMO

BACKGROUND: In late 2021, the SARS-CoV-2 Omicron (B.1.1.529) variant of concern (VoC) was reported with many mutations in the viral spike protein that were predicted to enhance transmissibility and allow viral escape of neutralizing antibodies. Within weeks of the first report of B.1.1.529, this VoC has rapidly spread throughout the world, replacing previously circulating strains of SARS-CoV-2 and leading to a resurgence in COVID-19 cases even in populations with high levels of vaccine- and infection-induced immunity. Studies have shown that B.1.1.529 is less sensitive to protective antibody conferred by previous infections and vaccines developed against earlier lineages of SARS-CoV-2. The ability of B.1.1.529 to spread even among vaccinated populations has led to a global public health demand for updated vaccines that can confer protection against B.1.1.529. METHODS: We rapidly developed a replicating RNA vaccine expressing the B.1.1.529 spike and evaluated immunogenicity in mice and hamsters. We also challenged hamsters with B.1.1.529 and evaluated whether vaccination could protect against viral shedding and replication within respiratory tissue. FINDINGS: We found that mice previously immunized with A.1-specific vaccines failed to elevate neutralizing antibody titers against B.1.1.529 following B.1.1.529-targeted boosting, suggesting pre-existing immunity may impact the efficacy of B.1.1.529-targeted boosters. Furthermore, we found that our B.1.1.529-targeted vaccine provides superior protection compared to the ancestral A.1-targeted vaccine in hamsters challenged with the B.1.1.529 VoC after a single dose of each vaccine. INTERPRETATION: Our data suggest that B.1.1.529-targeted vaccines may provide superior protection against B.1.1.529 but pre-existing immunity and timing of boosting may need to be considered for optimum protection. FUNDING: This research was supported in part by the Intramural Research Program, NIAID/NIH, Washington Research Foundation and by grants 27220140006C (JHE), AI100625, AI151698, and AI145296 (MG).


Assuntos
COVID-19 , Vacinas Virais , Animais , Anticorpos Neutralizantes , Anticorpos Antivirais , COVID-19/prevenção & controle , Cricetinae , Camundongos , RNA , SARS-CoV-2/genética , Glicoproteína da Espícula de Coronavírus/genética , Vacinas Sintéticas , Vacinas de mRNA
17.
EBioMedicine ; 83: 104240, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36041265

RESUMO

BACKGROUND: The live-attenuated yellow fever vaccine YF17D holds great promise as alternative viral vector vaccine platform, showcased by our previously presented potent severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccine candidate YF-S0. Besides protection from SARS-CoV-2, YF-S0 also induced strong yellow fever virus (YFV)-specific immunity, suggestive for full dual activity. A vaccine concomitantly protecting from SARS-CoV-2 and YFV would be of great benefit for those living in YFV-endemic areas with limited access to current SARS-CoV-2 vaccines. However, for broader applicability, pre-existing vector immunity should not impact the potency of such YF17D-vectored vaccines. METHODS: The immunogenicity and efficacy of YF-S0 against YFV and SARS-CoV-2 in the presence of strong pre-existing YFV immunity were evaluated in mouse and hamster challenge models. FINDINGS: Here, we show that a single dose of YF-S0 is sufficient to induce strong humoral and cellular immunity against YFV as well as SARS-CoV-2 in mice and hamsters; resulting in full protection from vigorous YFV challenge in either model; in mice against lethal intracranial YF17D challenge, and in hamsters against viscerotropic infection and liver disease following challenge with highly pathogenic hamster-adapted YFV-Asibi strain. Importantly, strong pre-existing immunity against the YF17D vector did not interfere with subsequent YF-S0 vaccination in mice or hamsters; nor with protection conferred against SARS-CoV-2 strain B1.1.7 (Alpha variant) infection in hamsters. INTERPRETATION: Our findings warrant the development of YF-S0 as dual SARS-CoV-2 and YFV vaccine. Contrary to other viral vaccine platforms, use of YF17D does not suffer from pre-existing vector immunity. FUNDING: Stated in the acknowledgments.


Assuntos
COVID-19 , Vacinas Virais , Vacina contra Febre Amarela , Febre Amarela , Animais , Anticorpos Antivirais , COVID-19/prevenção & controle , Vacinas contra COVID-19 , Cricetinae , Humanos , Camundongos , SARS-CoV-2 , Vacinas Virais/genética , Febre Amarela/prevenção & controle , Vírus da Febre Amarela/genética
18.
Vaccine ; 40(37): 5494-5503, 2022 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-35963820

RESUMO

In recent years, several advances have been observed in vaccinology especially for neglected tropical diseases (NTDs). One of the tools employed is epitope prediction by immunoinformatic approaches that reduce the time and cost to develop a vaccine. In this scenario, immunoinformatics is being more often used to develop vaccines for NTDs, in particular visceral leishmaniasis (VL) which is proven not to have an effective vaccine yet. Based on that, in a previous study, two predicted T-cell multi-epitope chimera vaccines were experimentally validated in BALB/c mice to evaluate the immunogenicity, central and effector memory and protection against VL. Considering the results obtained in the mouse model, we assessed the immune response of these chimeras inMesocricetus auratushamster, which displays, experimentally, similar pathological status to human and dog VL disease. Our findings indicate that both chimeras lead to a dominant Th1 response profile, inducing a strong cellular response by increasing the production of IFN-γ and TNF-α cytokines associated with a decrease in IL-10. Also, the chimeras reduced the spleen parasite load and the weight a correlation between protector immunological mechanisms and consistent reduction of the parasitic load was observed. Our results demonstrate that both chimeras were immunogenic and corroborate with findings in the mouse model. Therefore, we reinforce the use of the hamster as a pre-clinical model in vaccination trials for canine and human VL and the importance of immunoinformatic to identify epitopes to design vaccines for this important neglected disease.


Assuntos
Doenças do Cão , Leishmania infantum , Vacinas contra Leishmaniose , Leishmaniose Visceral , Células Th1 , Vacinas , Adjuvantes Imunológicos , Animais , Antígenos de Protozoários , Quimera , Cricetinae , Citocinas , Cães , Epitopos de Linfócito T , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Baço
19.
Cell Rep ; 40(7): 111214, 2022 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-35952673

RESUMO

Vaccine-associated enhanced respiratory disease (VAERD) is a severe complication for some respiratory infections. To investigate the potential for VAERD induction in coronavirus disease 2019 (COVID-19), we evaluate two vaccine leads utilizing a severe hamster infection model: a T helper type 1 (TH1)-biased measles vaccine-derived candidate and a TH2-biased alum-adjuvanted, non-stabilized spike protein. The measles virus (MeV)-derived vaccine protects the animals, but the protein lead induces VAERD, which can be alleviated by dexamethasone treatment. Bulk transcriptomic analysis reveals that our protein vaccine prepares enhanced host gene dysregulation in the lung, exclusively up-regulating mRNAs encoding the eosinophil attractant CCL-11, TH2-driving interleukin (IL)-19, or TH2 cytokines IL-4, IL-5, and IL-13. Single-cell RNA sequencing (scRNA-seq) identifies lung macrophages or lymphoid cells as sources, respectively. Our findings imply that VAERD is caused by the concerted action of hyperstimulated macrophages and TH2 cytokine-secreting lymphoid cells and potentially links VAERD to antibody-dependent enhancement (ADE). In summary, we identify the cytokine drivers and cellular contributors that mediate VAERD after TH2-biased vaccination.


Assuntos
COVID-19 , Vacinas , Animais , Anticorpos Antivirais , Cricetinae , Citocinas/metabolismo , Imunização , Pulmão/patologia , Camundongos , Camundongos Endogâmicos BALB C , Células Th1 , Células Th2 , Vacinação
20.
Mol Neurobiol ; 59(10): 6534-6551, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35970974

RESUMO

Activation and proliferation of microglia are one of the hallmarks of prion disease and is usually accompanied by increased levels of various cytokines and chemokines. Our previous study demonstrated that the level of brain macrophage colony-stimulating factor (M-CSF) was abnormally elevated during prion infection, but its association with PrPSc is not completely clear. In this study, colocalization of the increased M-CSF with accumulated PrPSc was observed by IHC with serial brain sections. Reliable molecular interaction between total PrP and M-CSF was observed in the brain of 263 K-infected hamsters and in cultured prion-infected cell line. Immunofluorescent assays showed that morphological colocalization of M-CSF with neurons and microglia, but not with astrocytes in brains of scrapie-infected animals. The transcriptional and expressing levels of CSF1R were also significantly increased in prion-infected cell line and mice, and colocalization of CSF1R with neurons and microglia was observed in the brains of prion-infected mouse models. Removal of PrPSc replication by resveratrol in SMB-S15 cells induced limited reductions of cellular levels of M-CSF and CSF1R. In addition, we found that the level of IL-34, another ligand of CSF1R, did not change significantly after prion infection, but its distribution on the cell types in the brains shifted from neurons in healthy mice to the proliferated astrocytes and microglia in scrapie-infected mice. Our data demonstrate activation of M-CSF/IL-34/CSF1R signaling in the microenvironment of prion infection, strongly indicating its vital role in the pathophysiology of prions. It provides solid scientific evidence for the therapeutic potential of inhibiting M-CSF/CSF1R signaling in prion diseases.


Assuntos
Doenças Priônicas , Príons , Scrapie , Animais , Encéfalo/metabolismo , Linhagem Celular , Cricetinae , Fator Estimulador de Colônias de Macrófagos/metabolismo , Camundongos , Proteínas PrPSc/metabolismo , Proteínas da Gravidez , Doenças Priônicas/metabolismo , Príons/metabolismo , Receptores de Fator Estimulador das Colônias de Granulócitos e Macrófagos/metabolismo , Roedores/metabolismo , Scrapie/metabolismo
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