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1.
Anim Sci J ; 94(1): e13804, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36617429

RESUMO

We investigated VEGF expression in the uterus during the estrous cycle in the golden hamster (Mesocricetus auratus). Reverse transcription polymerase chain reaction of genes expressed in the uterus revealed the presence of at least three different VEGF isoforms (hamster VEGF188, VEGF164, and VEGF120). They were highly homologous to the respective mouse and human isoforms. Furthermore, VEGF164 and VEGF120 were predominantly expressed in the hamster uterus during the estrous cycle. In situ hybridization revealed that VEGF is expressed only in the luminal and glandular epithelium of the endometrium but not in the stromal cells or myometrium. The positive reaction of luminal and glandular epithelial cells on day 4 of the estrous cycle (day 1 = day of ovulation) was a little stronger than that of other days of the cycle. These findings suggest that VEGF molecules are secreted by endometrial epithelial cells and play an important role in the maintenance of blood vessels in the endometrial stroma. These results also suggest that uterine changes, such as edema, observed from day 4 to day 1 of the estrous cycle, are expected to occur primarily through the action of VEGF secreted by the uterine endometrial epithelium in preparation for subsequent embryo implantation.


Assuntos
Útero , Fator A de Crescimento do Endotélio Vascular , Cricetinae , Feminino , Humanos , Animais , Camundongos , Fator A de Crescimento do Endotélio Vascular/genética , Fator A de Crescimento do Endotélio Vascular/metabolismo , Mesocricetus , Útero/metabolismo , Fatores de Crescimento do Endotélio Vascular/metabolismo , Endométrio/metabolismo , Ciclo Estral , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo
2.
JCI Insight ; 8(1)2023 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-36625345

RESUMO

Substantial clinical evidence supports the notion that ciliary function in the airways is important in COVID-19 pathogenesis. Although ciliary damage has been observed in both in vitro and in vivo models, the extent or nature of impairment of mucociliary transport (MCT) in in vivo models remains unknown. We hypothesize that SARS-CoV-2 infection results in MCT deficiency in the airways of golden Syrian hamsters that precedes pathological injury in lung parenchyma. Micro-optical coherence tomography was used to quantitate functional changes in the MCT apparatus. Both genomic and subgenomic viral RNA pathological and physiological changes were monitored in parallel. We show that SARS-CoV-2 infection caused a 67% decrease in MCT rate as early as 2 days postinfection (dpi) in hamsters, principally due to 79% diminished airway coverage of motile cilia. Correlating quantitation of physiological, virological, and pathological changes reveals steadily descending infection from the upper airways to lower airways to lung parenchyma within 7 dpi. Our results indicate that functional deficits of the MCT apparatus are a key aspect of COVID-19 pathogenesis, may extend viral retention, and could pose a risk factor for secondary infection. Clinically, monitoring abnormal ciliated cell function may indicate disease progression. Therapies directed toward the MCT apparatus deserve further investigation.


Assuntos
COVID-19 , Cricetinae , Animais , Mesocricetus , COVID-19/patologia , Depuração Mucociliar , SARS-CoV-2 , Modelos Animais de Doenças , Pulmão/diagnóstico por imagem , Pulmão/patologia , Progressão da Doença
3.
Oncotarget ; 14: 23-39, 2023 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-36634224

RESUMO

The oral mucositis is a mucosal alteration that usually arises from oncological treatments, such as chemotherapy, and it is characterized as an inflammatory process. The aim of this study is to demonstrate the chromatographic constitution of Andiroba oil, comparing and evaluating Andiroba oil and laser scarring efficiency in treatments of oral mucositis in hamsters. These animals were submitted to 5-Fluorouracil. A total of 122 animals were used, randomized and divided into the following groups: (a) positive control; (b) laser associated to andiroba oil; (c) laser; (d) andiroba oil; (e) negative control; (f) cyclophosphamide (genotoxicity control). The induction of oral mucositis occurred by the administration of intraperitoneal Fluorouracila (60 mg/kg) and trauma to the mucosa. The laser protocol was performed once a day and the andiroba oil applied 3 times a day (1,5 ml/day). The mucosae were photographed and removed for clinical and histopathological analysis on day 4, 8, 12 and 15. The analysis was based in OM severity, in specific scoring for the clinical and histopathological aspect. Toxicity was evaluated on day 15 using comet assay and it was performed by variant DNA damage parameters. The data were analysed using analysis of variance (ANOVA) Tukey post-test and Kruskal-Wallis Dunn post-test. The "andiroba oil" and "laser" groups presented better results when compared to the control groups and the treatment associations. The andiroba oil presented the best scarring results, even considering its efficiency proximity to the laser treatment. Andiroba and laser, separately, did not present genotoxicity, however their association evidences damage to DNA.


Assuntos
Terapia com Luz de Baixa Intensidade , Estomatite , Animais , Cricetinae , Cicatriz , Fluoruracila/toxicidade , Terapia com Luz de Baixa Intensidade/métodos , Mesocricetus , Estomatite/induzido quimicamente
4.
Exp Parasitol ; 245: 108458, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36592712

RESUMO

Dentostomella translucida is an oxyurid nematode that was first discovered in the Mongolian gerbil but has also been detected in other wild and housed rodents. In conventional laboratory animals, oxyurid nematode parasites are widespread infections. A proven treatment strategy for pinworm eradication is the oral application of benzimidazoles, such as fenbendazole. In general, this drug is regarded as safe with minimal side effects. Nevertheless, in Sprague Dawley rats, a significantly reduced litter size could be seen after longer treatment with fenbendazole. Even though Dentostomella translucida was already described in Syrian golden hamsters (Mesocricetus auratus), data on treatment with fenbendazole and its effects on reproduction is lacking. Therefore, the main purposes of the study were (1) the verification of the effectiveness of fenbendazole as medicated feed (150 ppm) against this parasite in naturally infected Syrian golden hamsters in conventional husbandry and (2) monitoring of possible effects on reproduction during the treatment. Results show that fenbendazole treatment was highly effective against Dentostomella translucida, as numbers of pinworm eggs in the faeces were significantly reduced already after the first week of treatment in all animals. After four weeks of treatment, eggs were eradicated entirely. Interestingly, the average weaning weight was significantly reduced during treatment, but the litters were in good health.


Assuntos
Fenbendazol , Nematoides , Animais , Ratos , Cricetinae , Mesocricetus , Fenbendazol/uso terapêutico , Ratos Sprague-Dawley , Gerbillinae/parasitologia
5.
Antiviral Res ; 210: 105522, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36592667

RESUMO

In 1998, Mike Bray and colleagues published the first immunocompetent laboratory mouse model of Ebola virus disease. Often labeled by peer reviewers as inferior to large nonhuman primate efforts, this model initially laid the foundation for the recent establishment of panel-derived cross-bred and humanized mouse models and a golden hamster model. Nonhuman primate research has always been associated with ethical concerns and is sometimes deemed scientifically questionable due to the necessarily low animal numbers in individual studies. Independent of these concerns, the now-global severe shortage of commercially available large nonhuman primates may pragmatically push research toward increased and improved rodent modeling that may altogether replace nonhuman primate studies in the short term as well as in an optimal future.


Assuntos
Ebolavirus , Doença pelo Vírus Ebola , Cricetinae , Animais , Camundongos , Primatas , Mesocricetus , Modelos Animais de Doenças
6.
Int J Mol Sci ; 24(2)2023 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-36674893

RESUMO

Like many social behaviors, aggression can be rewarding, leading to behavioral plasticity. One outcome of reward-induced aggression is the long-term increase in the speed in which future aggression-based encounters is initiated. This form of aggression impacts dendritic structure and excitatory synaptic neurotransmission in the nucleus accumbens, a brain region well known to regulate motivated behaviors. Yet, little is known about the intracellular signaling mechanisms that drive these structural/functional changes and long-term changes in aggressive behavior. This study set out to further elucidate the intracellular signaling mechanisms regulating the plasticity in neurophysiology and behavior that underlie the rewarding consequences of aggressive interactions. Female Syrian hamsters experienced zero, two or five aggressive interactions and the phosphorylation of proteins in reward-associated regions was analyzed. We report that aggressive interactions result in a transient increase in the phosphorylation of extracellular-signal related kinase 1/2 (ERK1/2) in the nucleus accumbens. We also report that aggressive interactions result in a transient decrease in the phosphorylation of mammalian target of rapamycin (mTOR) in the medial prefrontal cortex, a major input structure to the nucleus accumbens. Thus, this study identifies ERK1/2 and mTOR as potential signaling pathways for regulating the long-term rewarding consequences of aggressive interactions. Furthermore, the recruitment profile of the ERK1/2 and the mTOR pathways are distinct in different brain regions.


Assuntos
Sistema de Sinalização das MAP Quinases , Núcleo Accumbens , Cricetinae , Animais , Feminino , Núcleo Accumbens/metabolismo , Mesocricetus , Fosforilação , Agressão/fisiologia , Córtex Pré-Frontal/metabolismo , Serina-Treonina Quinases TOR/metabolismo
7.
Vaccine ; 41(4): 892-902, 2023 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-36528447

RESUMO

As novel SARS-CoV-2 Variants of Concern emerge, the efficacy of existing vaccines against COVID-19 is declining. A possible solution to this problem lies in the development of a live attenuated vaccine potentially able of providing cross-protective activity against a wide range of SARS-CoV-2 antigenic variants. Cold-adapted (ca) SARS-CoV-2 variants, Dubrovka-ca-B4 (D-B4) and Dubrovka-ca-D2 (D-D2), were obtained after long-term passaging of the Dubrovka (D) strain in Vero cells at reduced temperatures. Virulence, immunogenicity, and protective activity of SARS-CoV-2 variants were evaluated in experiments on intranasal infection of Syrian golden hamsters (Mesocricetus auratus). In animal model infecting with ca variants, the absence of body weight loss, the significantly lower viral titer and viral RNA concentration in animal tissues, the less pronounced inflammatory lesions in animal lungs as compared with the D strain indicated the reduced virulence of the virus variant. Single intranasal immunization with D-B4 and D-D2 variants induced the production of neutralizing antibodies in hamsters and protected them from infection with the D strain and the development of severe pneumonia. It was shown that for ca SARS-CoV-2 variants, the temperature-sensitive (ts) phenotype was not obligate for virulence reduction. Indeed, the D-B4 variant, which did not possess the ts phenotype but had lost the ability to infect human lung cells Calu-3, exhibited reduced virulence in hamsters. Consequently, the potential phenotypic markers of attenuation of ca SARS-CoV-2 variants are the ca phenotype, the ts phenotype, and the change in species specificity of the virus. This study demonstrates the great potential of SARS-CoV-2 cold adaptation as a strategy to develop a live attenuated COVID-19 vaccine.


Assuntos
COVID-19 , SARS-CoV-2 , Cricetinae , Animais , Chlorocebus aethiops , Humanos , Células Vero , Temperatura , COVID-19/prevenção & controle , Vacinas contra COVID-19 , Anticorpos Antivirais , Mesocricetus , Anticorpos Neutralizantes , Glicoproteína da Espícula de Coronavírus
8.
Antiviral Res ; 209: 105490, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36521633

RESUMO

Human infection with Sosuga virus (SOSV), a recently discovered pathogenic paramyxovirus, has been reported in one individual to date. No animal models of disease are currently available for SOSV. Here, we describe initial characterization of experimental infection in Syrian hamsters, including kinetics of virus dissemination and replication, and the corresponding clinical parameters, immunological responses, and histopathology. We demonstrate susceptibility of hamsters to infection in the absence of clinical signs or significant histopathologic findings in tissues.


Assuntos
Paramyxoviridae , Cricetinae , Animais , Humanos , Mesocricetus , Paramyxoviridae/fisiologia , Modelos Animais , Modelos Animais de Doenças
10.
Nat Commun ; 13(1): 7675, 2022 12 12.
Artigo em Inglês | MEDLINE | ID: mdl-36509737

RESUMO

Although ocular manifestations are reported in patients with COVID-19, consensus on ocular tropism of SARS-CoV-2 is lacking. Here, we infect K18-hACE2 transgenic mice with SARS-CoV-2 using various routes. We observe ocular manifestation and retinal inflammation with production of pro-inflammatory cytokines in the eyes of intranasally (IN)-infected mice. Intratracheal (IT) infection results in dissemination of the virus from the lungs to the brain and eyes via trigeminal and optic nerves. Ocular and neuronal invasions are confirmed using intracerebral (IC) infection. Notably, the eye-dropped (ED) virus does not cause lung infection and becomes undetectable with time. Ocular and neurotropic distribution of the virus in vivo is evident in fluorescence imaging with an infectious clone of SARS-CoV-2-mCherry. The ocular tropic and neuroinvasive characteristics of SARS-CoV-2 are confirmed in wild-type Syrian hamsters. Our data can improve the understanding regarding viral transmission and clinical characteristics of SARS-CoV-2 and help in improving COVID-19 control procedures.


Assuntos
COVID-19 , SARS-CoV-2 , Cricetinae , Camundongos , Animais , Modelos Animais de Doenças , Camundongos Transgênicos , Pulmão , Mesocricetus , Inflamação
11.
Parasit Vectors ; 15(1): 468, 2022 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-36522762

RESUMO

BACKGROUND: Visceral leishmaniasis (VL) is the most severe form of all leishmanial infections and is caused by infection with protozoa of Leishmania donovani and Leishmania infantum. This parasitic disease occurs in over 80 countries and its geographic distribution is on the rise. Although the interaction between the intestinal microbiome and the immune response has been established in several pathologies, it has not been widely studied in leishmaniasis. The Syrian hamster is the most advanced laboratory model for developing vaccines and new drugs against VL. In the study reported here, we explored the relationship between the intestinal microbiome and infection with L. infantum in this surrogate host. METHODS: Male Syrian hamsters (120-140 g) were inoculated with 108 promastigotes of a canine-derived L. infantum strain or left as uninfected control animals. Infection was maintained for 19 weeks (endpoint) and monitored by an immunoglobulin G (IgG) enyzme-linked immunosorbent assay throughout the experiment. Individual faecal samples, obtained at weeks 16, 18 and 19 post-inoculation, were analysed to determine the 16S metagenomic composition (the operational taxonomic units [OTUs] of the intestinal microbiome and the comparison between groups were FDR (false discovery rate)-adjusted). RESULTS: Leishmania infantum infection elicited moderate clinical signs and lesions and a steady increase in specific anti-Leishmania serum IgG. The predominant phyla (Firmicutes + Bacteriodetes: > 90%), families (Muribaculaceae + Lachnospiraceae + Ruminococcaceae: 70-80%) and genera found in the uninfected hamsters showed no significant variations throughout the experiment. Leishmania infantum infection provoked a slightly higher-albeit non-significant-value for the Firmicutes/Bacteriodetes ratio but no notable differences were found in the relative abundance or diversity of phyla and families. The microbiome of the infected hamsters was enriched in CAG-352, whereas Lachnospiraceae UCG-004, the [Eubacterium] ventriosum group and Allobaculum were less abundant. CONCLUSIONS: The lack of extensive significant differences between hamsters infected and uninfected with L. infantum in the higher taxa (phyla, families) and the scarce variation found, which was restricted to genera with a low relative abundance, suggest that there is no clear VL infection-intestinal microbiome axis in hamsters. Further studies are needed (chronic infections, co-abundance analyses, intestinal sampling, functional analysis) to confirm these findings and to determine more precisely the possible relationship between microbiome composition and VL infection.


Assuntos
Microbioma Gastrointestinal , Leishmania infantum , Leishmaniose Visceral , Leishmaniose , Cricetinae , Cães , Masculino , Animais , Mesocricetus , Leishmaniose Visceral/parasitologia , Leishmaniose/parasitologia , Imunoglobulina G
12.
Vopr Virusol ; 67(5): 403-413, 2022 11 19.
Artigo em Russo | MEDLINE | ID: mdl-36515286

RESUMO

INTRODUCTION: Convalescent COVID-19 patients have various signs of central nervous system damage, including those directly associated with SARS-CoV-2. Hence, studies of SARS-COV-2 related morphological changes in neocortex are particularly relevant for understanding the mechanisms of their formation and development of approaches to preclinical evaluation of the effectiveness of antiviral drugs. The purpose of the research is a longitudinal study of the ultrastructural alterations in Syrian hamsters neocortex after experimental SARS-CoV-2 infection. MATERIALS AND METHODS: Male Syrian hamsters weighing 80100 g, aged 4 to 6 weeks, were infected with 26 l SARS-CoV-2 intranasally with 4104 TCD50/ml of viral particles. The animals were euthanized on days 3, 7 or 28 post-infection, the brain was extracted with the cortex excision. The material analysis was performed using transmission electron microscopy. RESULTS AND DISCUSSION: On day 3 post-infection, the number of moderately hyperchromic neurons in neocortex increased, while by the day 7 the number of apoptotic cells significantly increased. Simultaneously, an increased signs of neuronophagy and representation of atypical glia were observed. Increased number of altered oligodendrocytes was observed on day 28 post-infection. Viral invasion was accompanied by changes in neocortical cells since day 3 post-infection, such as transformation of their nucleus, the rough endoplasmic reticulum and the Golgi vesicles as well as microvascular spasm with perivascular edema. CONCLUSION: As a result of electron microscopic study, the ultrastructural alterations in neocortex were described in an experimental model of SARS-CoV-2 infection. The findings can be used to identify the mechanisms of infection pathogenesis and to search for the new directions in development of medicines.


Assuntos
COVID-19 , Coronaviridae , Neocórtex , Cricetinae , Animais , Masculino , SARS-CoV-2 , Mesocricetus , Estudos Longitudinais , Elétrons , Modelos Animais de Doenças
13.
Front Immunol ; 13: 1009424, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36524125

RESUMO

Introduction: The innate immune responses of upper airway could further our understanding toward antiviral strategies against SARS-CoV-2. We characterize the potential of interferon (IFN)-λ as an innate immune inducer for the rapid clearance of SARS-CoV-2 in the lung and the therapeutic efficacy of intranasal inoculation of IFN-λ to resolve acute lung infection. Methods: Syrian golden hamsters were infected with SARS-CoV-2 and the dynamics of SARS-CoV-2 infection depending on IFN-λ inoculation were tested. Results: SARS-CoV-2-infected Syrian golden hamsters exhibited a significant decrease in body weight and high viral mRNA level at 3 days post-infection (dpi). Although viral replication was reduced completely from 7 dpi, the pathologic findings remained prominent until 14 dpi in the lung of hamsters. The transcription of IFN-λ was significantly induced in response to SARS-CoV-2 infection with the increase of IFN-stimulated genes. Intranasal inoculation of IFN-λ restricted SARS-CoV-2 replication in the lungs of infected completely from 3 dpi with markedly reduction of inflammatory cytokines. The transcriptional phenotypes were altered to the direction of damage repair and tissue remodeling in the lungs of SARS-CoV-2-infected hamsters following intranasal inoculation of IFN-λ, which improved SARS-CoV-2-caused lung damage. Conclusion: Collectively, our findings suggest that IFN-λ might be a potent innate immune inducer in the lung and intranasal inoculation of IFN-λ resolves SARS-CoV-2 infection with rapid viral clearance and improvement of lung damage.


Assuntos
COVID-19 , SARS-CoV-2 , Cricetinae , Animais , COVID-19/patologia , Carga Viral , Mesocricetus , Pulmão
14.
Front Cell Infect Microbiol ; 12: 979641, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36405962

RESUMO

We evaluated the immunogenicity and protective ability of a chimpanzee replication-deficient adenovirus vectored COVID-19 vaccine (BV-AdCoV-1) expressing a stabilized pre-fusion SARS-CoV-2 spike glycoprotein in golden Syrian hamsters. Intranasal administration of BV-AdCoV-1 elicited strong humoral and cellular immunity in the animals. Furthermore, vaccination prevented weight loss, reduced SARS-CoV-2 infectious virus titers in the lungs as well as lung pathology and provided protection against SARS-CoV-2 live challenge. In addition, there was no vaccine-induced enhanced disease nor immunopathological exacerbation in BV-AdCoV-1-vaccinated animals. Furthermore, the vaccine induced cross-neutralizing antibody responses against the ancestral strain and the B.1.617.2, Omicron(BA.1), Omicron(BA.2.75) and Omicron(BA.4/5) variants of concern. These results demonstrate that BV-AdCoV-1 is potentially a promising candidate vaccine to prevent SARS-CoV-2 infection, and to curtail pandemic spread in humans.


Assuntos
COVID-19 , Vacinas Virais , Cricetinae , Animais , Humanos , Mesocricetus , Administração Intranasal , Pan troglodytes , COVID-19/prevenção & controle , Anticorpos Antivirais , Vacinas contra COVID-19 , SARS-CoV-2/genética , Adenoviridae/genética
15.
Front Cell Infect Microbiol ; 12: 1019723, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36339331

RESUMO

Objectives: Close contact with patients with COVID-19 is speculated to be the most common cause of viral transmission, but the pathogenesis of COVID-19 by close contact remains to be elucidated. In addition, despite olfactory impairment being a unique complication of COVID-19, the impact of SARS-CoV-2 on the olfactory cell lineage has not been fully validated. This study aimed to elucidate close-contact viral transmission to the nose and lungs and to investigate the temporal damage in the olfactory receptor neuron (ORN) lineage caused by SARS-CoV-2. Methods: Syrian hamsters were orally administered SARS-CoV-2 nonvariant nCoV-19/JPN/TY/WK521/2020 as direct-infection models. On day 3 after inoculation, infected and uninfected hamsters were housed in the same cage for 30 minutes. These uninfected hamsters were subsequently assigned to a close-contact group. First, viral presence in the nose and lungs was verified in the infection and close-contact groups at several time points. Next, the impacts on the olfactory epithelium, including olfactory progenitors, immature ORNs, and mature ORNs were examined histologically. Then, the viral transmission status and chronological changes in tissue damage were compared between the direct-infection and close-contact groups. Results: In the close-contact group, viral presence could not be detected in both the nose and lungs on day 3, and the virus was identified in both tissues on day 7. In the direct-infection group, the viral load was highest in the nose and lungs on day 3, decreased on day 7, and was no longer detectable on day 14. Histologically, in the direct-infection group, mature ORNs were most depleted on day 3 (p <0.001) and showed a recovery trend on day 14, with similar trends for olfactory progenitors and immature ORNs. In the close-contact group, there was no obvious tissue damage on day 3, but on day 7, the number of all ORN lineage cells significantly decreased (p <0.001). Conclusion: SARS-CoV-2 was transmitted even after brief contact and subsequent olfactory epithelium and lung damage occurred more than 3 days after the trigger of infection. The present study also indicated that SARS-CoV-2 damages all ORN lineage cells, but this damage can begin to recover approximately 14 days post infection.


Assuntos
COVID-19 , Transtornos do Olfato , Cricetinae , Animais , Humanos , SARS-CoV-2 , Mesocricetus , Linhagem da Célula , Modelos Animais de Doenças
16.
Nat Commun ; 13(1): 6792, 2022 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-36357440

RESUMO

Few live attenuated severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccines are in pre-clinical or clinical development. We seek to attenuate SARS-CoV-2 (isolate WA1/2020) by removing the polybasic insert within the spike protein and the open reading frames (ORFs) 6-8, and by introducing mutations that abolish non-structural protein 1 (Nsp1)-mediated toxicity. The derived virus (WA1-ΔPRRA-ΔORF6-8-Nsp1K164A/H165A) replicates to 100- to 1000-fold-lower titers than the ancestral virus and induces little lung pathology in both K18-human ACE2 (hACE2) transgenic mice and Syrian hamsters. Immunofluorescence and transcriptomic analyses of infected hamsters confirm that three-pronged genetic modifications attenuate the proinflammatory pathways more than the removal of the polybasic cleavage site alone. Finally, intranasal administration of just 100 PFU of the WA1-ΔPRRA-ΔORF6-8-Nsp1K164A/H165A elicits robust antibody responses in Syrian hamsters and protects against SARS-CoV-2-induced weight loss and pneumonia. As a proof-of-concept study, we demonstrate that live but sufficiently attenuated SARS-CoV-2 vaccines may be attainable by rational design.


Assuntos
COVID-19 , SARS-CoV-2 , Cricetinae , Camundongos , Animais , Humanos , SARS-CoV-2/genética , Mesocricetus , Formação de Anticorpos , Administração Intranasal , Vacinas contra COVID-19 , COVID-19/prevenção & controle , Pulmão/patologia , Camundongos Transgênicos , Glicoproteína da Espícula de Coronavírus/genética
17.
Cell Res ; 32(12): 1068-1085, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36357786

RESUMO

The emerging SARS-CoV-2 variants, commonly with many mutations in S1 subunit of spike (S) protein are weakening the efficacy of the current vaccines and antibody therapeutics. This calls for the variant-proof SARS-CoV-2 vaccines targeting the more conserved regions in S protein. Here, we designed a recombinant subunit vaccine, HR121, targeting the conserved HR1 domain in S2 subunit of S protein. HR121 consisting of HR1-linker1-HR2-linker2-HR1, is conformationally and functionally analogous to the HR1 domain present in the fusion intermediate conformation of S2 subunit. Immunization with HR121 in rabbits and rhesus macaques elicited highly potent cross-neutralizing antibodies against SARS-CoV-2 and its variants, particularly Omicron sublineages. Vaccination with HR121 achieved near-full protections against prototype SARS-CoV-2 infection in hACE2 transgenic mice, Syrian golden hamsters and rhesus macaques, and effective protection against Omicron BA.2 infection in Syrian golden hamsters. This study demonstrates that HR121 is a promising candidate of variant-proof SARS-CoV-2 vaccine with a novel conserved target in the S2 subunit for application against current and future SARS-CoV-2 variants.


Assuntos
Vacinas contra COVID-19 , COVID-19 , Animais , Cricetinae , Camundongos , Humanos , Coelhos , SARS-CoV-2 , Macaca mulatta , Mesocricetus , Glicoproteína da Espícula de Coronavírus/genética , COVID-19/prevenção & controle , Anticorpos Neutralizantes , Camundongos Transgênicos , Anticorpos Antivirais
18.
Sci Rep ; 12(1): 18694, 2022 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-36333445

RESUMO

SARS-CoV-2 exhibits a diverse host species range with variable outcomes, enabling differential host susceptibility studies to assess suitability for pre-clinical countermeasure and pathogenesis studies. Baseline virological, molecular and pathological outcomes were determined among multiple species-one Old World non-human primate (NHP) species (cynomolgus macaques), two New World NHP species (red-bellied tamarins; common marmosets) and Syrian hamsters-following single-dose, atraumatic intranasal administration of SARS-CoV-2/Victoria-01. After serial sacrifice 2, 10 and 28-days post-infection (dpi), hamsters and cynomolgus macaques displayed differential virus biodistribution across respiratory, gastrointestinal and cardiovascular systems. Uniquely, New World tamarins, unlike marmosets, exhibited high levels of acute upper airway infection, infectious virus recovery associated with mild lung pathology representing a host previously unrecognized as susceptible to SARS-CoV-2. Across all species, lung pathology was identified post-clearance of virus shedding (antigen/RNA), with an association of virus particles within replication organelles in lung sections analysed by electron microscopy. Disrupted cell ultrastructure and lung architecture, including abnormal morphology of mitochondria 10-28 dpi, represented on-going pathophysiological consequences of SARS-CoV-2 in predominantly asymptomatic hosts. Infection kinetics and host pathology comparators using standardized methodologies enables model selection to bridge differential outcomes within upper and lower respiratory tracts and elucidate longer-term consequences of asymptomatic SARS-CoV-2 infection.


Assuntos
COVID-19 , SARS-CoV-2 , Cricetinae , Animais , Distribuição Tecidual , Administração Intranasal , Modelos Animais de Doenças , Pulmão/patologia , Mesocricetus , Macaca fascicularis
19.
Viruses ; 14(11)2022 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-36423101

RESUMO

Positron emission tomography (PET) is becoming an important tool for the investigation of emerging infectious diseases in animal models. Usually, PET imaging is performed after intravenous (IV) radiotracer administration. However, IV injections are difficult to perform in some small animals, such as golden hamsters. This challenge is particularly evident in longitudinal imaging studies, and even more so in maximum containment settings used to study high-consequence pathogens. We propose the use of intramuscular (IM) administration of 2-deoxy-2[18F]fluoro-D-glucose ([18F]F-FDG) for PET imaging of hamsters in a biosafety level 4 (BSL-4) laboratory setting. After [18F]F-FDG administration via IM or IV (through surgically implanted vascular access ports), eight hamsters underwent static or dynamic PET scans. Time-activity curves (TACs) and standardized uptake values (SUVs) in major regions of interest (ROIs) were used to compare the two injection routes. Immediately after injection, TACs differed between the two routes. At 60 min post-injection, [18F]F-FDG activity for both routes reached a plateau in most ROIs except the brain, with higher accumulation in the liver, lungs, brain, and nasal cavities observed in the IM group. IM delivery of [18F]F-FDG is an easy, safe, and reliable alternative for longitudinal PET imaging of hamsters in a BSL-4 laboratory setting.


Assuntos
Fluordesoxiglucose F18 , Tomografia por Emissão de Pósitrons , Animais , Cricetinae , Mesocricetus , Tomografia por Emissão de Pósitrons/métodos , Encéfalo/diagnóstico por imagem , Glucose
20.
Bioorg Chem ; 129: 106185, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36240541

RESUMO

The evolving SARS-CoV-2 epidemic buffets the world, and the concerted efforts are needed to explore effective drugs. Mpro is an intriguing antiviral target for interfering with viral RNA replication and transcription. In order to get potential anti-SARS-CoV-2 agents, we established an enzymatic assay using a fluorogenic substrate to screen the inhibitors of Mpro. Fortunately, Acriflavine (ACF) and Proflavine Hemisulfate (PRF) with the same acridine scaffold were picked out for their good inhibitory activity against Mpro with IC50 of 5.60 ± 0.29 µM and 2.07 ± 0.01 µM, respectively. Further evaluation of MST assay and enzymatic kinetics experiment in vitro showed that they had a certain affinity to SARS-CoV-2 Mpro and were both non-competitive inhibitors. In addition, they inhibited about 90 % HCoV-OC43 replication in BHK-21 cells at 1 µM. Both compounds showed nano-molar activities against SARS-CoV-2 virus, which were superior to GC376 for anti-HCoV-43, and equivalent to the standard molecule remdesivir. Our study demonstrated that ACF and PRF were inhibitors of Mpro, and ACF has been previously reported as a PLpro inhibitor. Taken together, ACF and PRF might be dual-targeted inhibitors to provide protection against infections of coronaviruses.


Assuntos
Acriflavina , Proteases 3C de Coronavírus , Inibidores de Cisteína Proteinase , Proflavina , SARS-CoV-2 , Inibidores de Protease Viral , Acriflavina/farmacologia , Proflavina/farmacologia , SARS-CoV-2/efeitos dos fármacos , SARS-CoV-2/enzimologia , Proteases 3C de Coronavírus/antagonistas & inibidores , Inibidores de Cisteína Proteinase/farmacologia , Inibidores de Protease Viral/farmacologia , Mesocricetus , Animais , Cricetinae , Linhagem Celular , Replicação Viral/efeitos dos fármacos
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