Participation of both Host and Virus Factors in Induction of Severe Acute Respiratory Syndrome (SARS) in F344 Rats Infected with SARS Coronavirus

ABSTRACT To understand the pathogenesis and develop an animal model of severe acute respiratory syndrome (SARS)-associated coronavirus (SARS-CoV), the Frankfurt 1 SARS-CoV isolate was passaged serially in young F344 rats. Young rats were susceptible to SARS-CoV but cleared the virus rapidly within 3 to 5 days of intranasal inoculation. After 10 serial passages, replication and virulence of SARS-CoV were increased in the respiratory tract of young rats without clinical signs. By contrast, adult rats infected with the passaged virus showed respiratory symptoms and severe pathological lesions in the lung. Levels of inflammatory cytokines in sera and lung tissues were significantly higher in adult F344 rats than in young rats. During in vivo passage of SARS-CoV, a single amino acid substitution was introduced within the binding domain of the viral spike protein recognizing angiotensin-converting enzyme 2 (ACE2), which is known as a SARS-CoV receptor. The rat-passaged virus more efficiently infected CHO cells expressing rat ACE2 than did the original isolate. These results strongly indicate that host and virus factors such as advanced age and virus adaptation are critical for the development of SARS in rats.

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Single Amino Acid Substitutions in the Severe Acute Respiratory Syndrome Coronavirus Spike Glycoprotein Determine Viral Entry and Immunogenicity of a Major Neutralizing Domain

Journal of Virology ◽

10.1128/jvi.79.18.11638-11646.2005 ◽

2005 ◽

Vol 79 (18) ◽

pp. 11638-11646 ◽

Cited By ~ 38

Author(s):

Christopher E. Yi ◽

Lei Ba ◽

Linqi Zhang ◽

David D. Ho ◽

Zhiwei Chen

Keyword(s):

Amino Acid ◽

Severe Acute Respiratory Syndrome ◽

Viral Entry ◽

Neutralizing Antibodies ◽

Rational Design ◽

Antiviral Agents ◽

Single Amino Acid ◽

Major Mechanism ◽

The Difference

ABSTRACT Neutralizing antibodies (NAbs) against severe acute respiratory syndrome (SARS) coronavirus (SARS-CoV) spike (S) glycoprotein confer protection to animals experimentally infected with the pathogenic virus. We and others previously demonstrated that a major mechanism for neutralizing SARS-CoV was through blocking the interaction between the S glycoprotein and the cellular receptor angiotensin-converting enzyme 2 (ACE2). In this study, we used in vivo electroporation DNA immunization and a pseudovirus-based assay to functionally evaluate immunogenicity and viral entry. We characterized the neutralization and viral entry determinants within the ACE2-binding domain of the S glycoprotein. The deletion of a positively charged region SΔ(422-463) abolished the capacity of the S glycoprotein to induce NAbs in mice vaccinated by in vivo DNA electroporation. Moreover, the SΔ(422-463) pseudovirus was unable to infect HEK293T-ACE2 cells. To determine the specific residues that contribute to related phenotypes, we replaced eight basic amino acids with alanine. We found that a single amino acid substitution (R441A) in the full-length S DNA vaccine failed to induce NAbs and abolished viral entry when pseudoviruses were generated. However, another substitution (R453A) abolished viral entry while retaining the capacity for inducing NAbs. The difference between R441A and R453A suggests that the determinants for immunogenicity and viral entry may not be identical. Our findings provide direct evidence that these basic residues are essential for immunogenicity of the major neutralizing domain and for viral entry. Our data have implications for the rational design of vaccine and antiviral agents as well as for understanding viral tropism.

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In Vivo Acute Exposure to Polychlorinated Biphenyls: Effects on Free and Total Thyroxine in Rats

International Journal of Toxicology ◽

10.1177/1091581809344631 ◽

2009 ◽

Vol 28 (5) ◽

pp. 382-391 ◽

Cited By ~ 6

Author(s):

J. M. Hedge ◽

M. J. DeVito ◽

K. M. Crofton

Keyword(s):

Polychlorinated Biphenyls ◽

Transport Proteins ◽

Transferase Activity ◽

Adult Rats ◽

Subsequent Increase ◽

Catabolic Enzymes ◽

Young Rats ◽

Total Thyroxine ◽

Treatment Interaction

Hypothyroxinemia in rats has been well documented as a result of exposure to polychlorinated biphenyls (PCBs). Hypothetical mechanisms include induction of hepatic catabolic enzymes and cellular hormone transporters, and/or interference with plasma transport proteins. We hypothesized that if thyroxine displacement from transport proteins by PCBs occurs in vivo, it would result in increased free thyroxine (FT4). This study investigates the effects of a single oral dose of 2,2’,4,4’,5,5'-hexachlorobiphenyl (PCB 153 at 60 mg/kg) or 3,3’,4,4’,5,5'-hexachlorobiphenyl (PCB 169 at 1 mg/kg) on rats at 28 or 76 days of age. Total thyroxine (TT4) and FT4 were measured at 0.5, 1, 2, 4, 8, 24, or 48 hours post -dosing. Microsomal ethoxy- and pentoxy-resorufin-O-deethylase (EROD and PROD) activity and uridine diphosphoglucuronosyl transferase (UGT) activity were determined. No significant increase in TT4 or FT4 concentrations was seen at any time point. PCB 153 significantly decreased TT4 and FT4 in young and adult rats, with young rats showing a time-by-treatment interaction from 2 to 48 hours post -dosing in serum FT4. With PCB 169 exposure, young rats showed a decrease in FT4 only, whereas adult rats showed decreases in TT4 only. Hepatic EROD and PROD activities were both dramatically increased following PCB 169 and 153, respectively. Uridine diphosphoglucuronosyl transferase activity was increased only after PCB 169 exposure. These data demonstrate that neither PCB 153 nor PCB169 increased FT4, which supports the conclusion that these PCBs do not displace thyroxine from serum TTR, or if it does occur, there is no subsequent increase in serum FT4 in vivo.

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Development of Potent and Effective Synthetic SARS-CoV-2 Neutralizing Nanobodies

10.1101/2021.05.06.442911 ◽

2021 ◽

Author(s):

Maxwell A. Stefan ◽

Yooli K. Light ◽

Jennifer L. Schwedler ◽

Peter R. McIlroy ◽

Colleen M. Courtney ◽

...

Keyword(s):

Severe Acute Respiratory Syndrome ◽

Respiratory Virus ◽

Intervention Strategy ◽

Cellular Receptor ◽

Receptor Binding Domain ◽

Converting Enzyme ◽

Angiotensin Converting Enzyme 2 ◽

Preclinical Evaluation ◽

High Diversity

The respiratory virus responsible for Coronavirus disease 2019 (COVID-19), Severe acute respiratory syndrome coronavirus 2 (SARS-2), has impacted nearly every aspect of life worldwide, claiming the lives of over 2.5 million people globally, at the time of this publication. Neutralizing nanobodies (V H H) represent a promising therapeutic intervention strategy to address the current SARS-2 pandemic and provide a powerful toolkit to address future virus outbreaks. Using a synthetic, high-diversity V H H bacteriophage library, several potent neutralizing V H H antibodies were identified and evaluated for their capacity to tightly bind to the SARS-2 receptor-binding domain (RBD), to prevent binding of SARS-2 spike (S) to the cellular receptor Angiotensin-converting enzyme 2 (ACE2), and to neutralize viral infection. Preliminary preclinical evaluation of multiple nanobody candidates demonstrate that they are prophylactically and therapeutically effective in vivo against wildtype SARS-2. The identified and characterized nanobodies described herein represent viable candidates for further preclinical evaluation and another tool to add to our therapeutic arsenal to address the COVID-19 pandemic.

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Amino Acid Substitutions in the S2 Region Enhance Severe Acute Respiratory Syndrome Coronavirus Infectivity in Rat Angiotensin-Converting Enzyme 2-Expressing Cells

Journal of Virology ◽

10.1128/jvi.01143-07 ◽

2007 ◽

Vol 81 (19) ◽

pp. 10831-10834 ◽

Cited By ~ 7

Author(s):

Shuetsu Fukushi ◽

Tetsuya Mizutani ◽

Kouji Sakai ◽

Masayuki Saijo ◽

Fumihiro Taguchi ◽

...

Keyword(s):

Amino Acid ◽

Severe Acute Respiratory Syndrome ◽

Angiotensin Converting Enzyme ◽

Host Species ◽

Molecular Basis ◽

Amino Acid Substitutions ◽

Converting Enzyme ◽

S Protein ◽

Angiotensin Converting Enzyme 2 ◽

Virus Adaptation

ABSTRACT To clarify the molecular basis of severe acute respiratory syndrome coronavirus (SARS-CoV) adaptation to different host species, we serially passaged SARS-CoV in rat angiotensin-converting enzyme 2 (ACE2)-expressing cells. After 15 passages, the virus (Rat-P15) came to replicate effectively in rat ACE2-expressing cells. Two amino acid substitutions in the S2 region were found on the Rat-P15 S gene. Analyses of the infectivity of the pseudotype-bearing S protein indicated that the two substitutions in the S2 region, especially the S950F substitution, were responsible for efficient infection. Therefore, virus adaptation to different host species can be induced by amino acid substitutions in the S2 region.

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ACUTE TOXICITY EVALUATION OF PROTODIOSCIN RICH EXTRACT OF TRIGONELLA FOENUM-GRAECUM L IN RATS

Asian Journal of Pharmaceutical and Clinical Research ◽

10.22159/ajpcr.2016.v9s3.14706 ◽

2016 ◽

Vol 9 (9) ◽

pp. 152

Author(s):

Vijaykumar Kunvarji Parmar ◽

Ketan Variya ◽

Sandip Patel

Keyword(s):

Body Weight ◽

Acute Toxicity ◽

Clinical Signs ◽

Oral Gavage ◽

Adult Rats ◽

Trigonella Foenum Graecum ◽

Biochemical Analyses ◽

Histopathological Studies ◽

Trigonella Foenum Graecum L

ABSTRACTObjectives: The objective of this study was to investigate the acute toxicity of standardized protodioscin rich extract (PRE) of Trigonella foenumgraecumL (26.63% w/w; PRE).Methods: To evaluate the toxicity of PRE, the acute toxicity of the extract on adult rats were investigated. A fixed large dose of 2 g/kg body weight ofPRE was administrated by a single oral gavage, and 1 g/kg body weight of PRE was administered by intravenous according to the Organisation forEconomic Co-operation and Development guidelines.Results: In 2 weeks, PRE showed no obvious acute toxicity. There were no deaths in either group and no change in the clinical signs. The hematologicaland biochemical analyses showed some changes that returned to reference levels without impairment of homeostasis. The treatment did not induceuntoward changes in organs as shown by histological studies. The in vivo results showed that has low toxicity.Conclusion: PRE is safe and can be potentially used as an aphrodisiac in future studies.Keywords: Protodioscin, Aphrodisiac, Trigonella foenum-graecum, Organisation for Economic Co-operation and Development, Toxicity,Histopathological studies.

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SARS-Like Coronavirus WIV1-CoV Does Not Replicate in Egyptian Fruit Bats (Rousettus aegyptiacus)

Viruses ◽

10.3390/v10120727 ◽

2018 ◽

Vol 10 (12) ◽

pp. 727 ◽

Cited By ~ 9

Author(s):

Neeltje van Doremalen ◽

Alexandra Schäfer ◽

Vineet Menachery ◽

Michael Letko ◽

Trenton Bushmaker ◽

...

Keyword(s):

Severe Acute Respiratory Syndrome ◽

Angiotensin Converting Enzyme ◽

Clinical Signs ◽

Post Inoculation ◽

Converting Enzyme ◽

Fruit Bats ◽

Post Challenge ◽

Angiotensin Converting Enzyme 2 ◽

Specific Antibodies ◽

Modest Increase

Severe acute respiratory syndrome (SARS)-like WIV1-coronavirus (CoV) was first isolated from Rhinolophus sinicus bats and can use the human angiotensin converting enzyme 2 (ACE2) receptor. In the current study, we investigate the ability of WIV1-CoV to infect Rousettus aegyptiacus bats. No clinical signs were observed throughout the experiment. Furthermore, only four oropharyngeal swabs and two respiratory tissues, isolated on day 3 post inoculation, were found positive for viral RNA. Two out of twelve bats showed a modest increase in coronavirus specific antibodies post challenge. In conclusion, WIV1-CoV was unable to cause a robust infection in Rousettus aegyptiacus bats.

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A Review of Severe Acute Respiratory Syndrome Coronavirus 2 and Pathological Disorders in Patients

Journal of Pharmaceutical Care ◽

10.18502/jpc.v9i3.7373 ◽

2021 ◽

Author(s):

Ghorbat Saleh Ali ◽

Betul Ozdemir ◽

Zeliha Selamoglu

Keyword(s):

Severe Acute Respiratory Syndrome ◽

Respiratory Symptoms ◽

Digestive System ◽

Virus Disease ◽

Negative Effects ◽

Alveolar Cells ◽

Angiotensin Converting Enzyme 2 ◽

Stomach Pain ◽

New Type ◽

Cardiac System

Firstly, a new coronavirus emerged in Wuhan, China, sparking a pandemic of acute respiratory syndrome in humans. Corona virus disease-19 (COVID-19) was declared as a pandemic after the infection spread globally and disease caused by the new type of coronavirus, Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) was named as COVID-19. The virus originated from bats and has been passed to humans. Initially, SARS-CoV-19 infects respiratory system an acute serious viral infection mainly developed with over a million people worldwide were transmitted rapidly in a few months. SARS-CoV-19, progress a moderate to serious severe respiratory symptoms such as headache, cough, and breathlessness. Also, digestive system symptoms include nausea, vomiting, and stomach pain. Although the precise of the mechanism of inflammation unclear but this virus firstly use the angiotensin converting enzyme 2 (ACE2) receptor of the alveolar cells of lung tissue causing inflammation and cell death. Then virus spreads and affects other important organ and tissues with complex pathophysiological alterations, the coronary disease, pulmonary disease, chronic kidney disease and chronic liver disease are the most prevalent comorbidities among patients. In COVID-19 infection therapy lots agents recommended. Unfortunately, there is no clear effective drug for treatment. This review presented potential pathogenic pathway of the SARS-CoV-19 infection and symptoms in the patients and given the information about the negative effects on different systems in the respiratory, cardiac system, nervous system, gastrointestinal system, and urinary tract.

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Genetic Variation and Evolution of the 2019 Novel Coronavirus

Public Health Genomics ◽

10.1159/000513530 ◽

2021 ◽

pp. 1-13

Author(s):

Salvatore Dimonte ◽

Muhammed Babakir-Mina ◽

Taib Hama-Soor ◽

Salar Ali

Keyword(s):

Amino Acid ◽

Receptor Binding ◽

Rapid Evolution ◽

Single Amino Acid ◽

Angiotensin Converting Enzyme 2 ◽

New Type ◽

Amino Acid Mutations ◽

Host Infection ◽

Human Coronaviruses ◽

Novel Coronavirus

Introduction: SARS-CoV-2 is a new type of coronavirus causing a pandemic severe acute respiratory syndrome (SARS-2). Coronaviruses are very diverting genetically and mutate so often periodically. The natural selection of viral mutations may cause host infection selectivity and infectivity. Methods: This study was aimed to indicate the diversity between human and animal coronaviruses through finding the rate of mutation in each of the spike, nucleocapsid, envelope, and membrane proteins. Results: The mutation rate is abundant in all 4 structural proteins. The most number of statistically significant amino acid mutations were found in spike receptor-binding domain (RBD) which may be because it is responsible for a corresponding receptor binding in a broad range of hosts and host selectivity to infect. Among 17 previously known amino acids which are important for binding of spike to angiotensin-converting enzyme 2 (ACE2) receptor, all of them are conservative among human coronaviruses, but only 3 of them significantly are mutated in animal coronaviruses. A single amino acid aspartate-454, that causes dissociation of the RBD of the spike and ACE2, and F486 which gives the strength of binding with ACE2 remain intact in all coronaviruses. Discussion/Conclusion: Observations of this study provided evidence of the genetic diversity and rapid evolution of SARS-CoV-2 as well as other human and animal coronaviruses.

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Virus Adaptation Following Experimental Infection of Chickens with a Domestic Duck Low Pathogenic Avian Influenza Isolate from the 2017 USA H7N9 Outbreak Identifies Polymorphic Mutations in Multiple Gene Segments

Viruses ◽

10.3390/v13061166 ◽

2021 ◽

Vol 13 (6) ◽

pp. 1166

Author(s):

Klaudia Chrzastek ◽

Karen Segovia ◽

Mia Torchetti ◽

Mary Lee Killian ◽

Mary Pantin-Jackwood ◽

...

Keyword(s):

Avian Influenza ◽

Experimental Infection ◽

Clinical Signs ◽

Interspecies Transmission ◽

Clinical Samples ◽

Domestic Duck ◽

Receptor Binding Site ◽

Synonymous Mutations ◽

Field Samples ◽

Virus Adaptation

In March 2017, highly pathogenic (HP) and low pathogenic (LP) avian influenza virus (AIV) subtype H7N9 were detected from poultry farms and backyard birds in several states in the southeast United States. Because interspecies transmission is a known mechanism for evolution of AIVs, we sought to characterize infection and transmission of a domestic duck-origin H7N9 LPAIV in chickens and genetically compare the viruses replicating in the chickens to the original H7N9 clinical field samples used as inoculum. The results of the experimental infection demonstrated virus replication and transmission in chickens, with overt clinical signs of disease and shedding through both oral and cloacal routes. Unexpectedly, higher levels of virus shedding were observed in some cloacal swabs. Next generation sequencing (NGS) analysis identified numerous non-synonymous mutations at the consensus level in the polymerase genes (i.e., PA, PB1, and PB2) and the hemagglutinin (HA) receptor binding site in viruses recovered from chickens, indicating possible virus adaptation in the new host. For comparison, NGS analysis of clinical samples obtained from duck specimen collected during the outbreak indicated three polymorphic sides in the M1 segment and a minor population of viruses carrying the D139N (21.4%) substitution in the NS1 segment. Interestingly, at consensus level, A/duck/Alabama (H7N9) had isoleucine at position 105 in NP protein, similar to HPAIV (H7N9) but not to LPAIV (H7N9) isolated from the same 2017 influenza outbreak in the US. Taken together, this work demonstrates that the H7N9 viruses could readily jump between avian species, which may have contributed to the evolution of the virus and its spread in the region.

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Importance and Antimicrobial Resistance of Mycoplasma bovis in Clinical Respiratory Disease in Feedlot Calves

Animals ◽

10.3390/ani11051470 ◽

2021 ◽

Vol 11 (5) ◽

pp. 1470

Author(s):

Ana García-Galán ◽

Juan Seva ◽

Ángel Gómez-Martín ◽

Joaquín Ortega ◽

Francisco Rodríguez ◽

...

Keyword(s):

Respiratory Disease ◽

Clinical Signs ◽

Antimicrobial Treatment ◽

Mycoplasma Bovis ◽

Bacterial Disease ◽

Feedlot Calves ◽

Fixed Panel

Bovine respiratory disease (BRD) is an important viral and/or bacterial disease that mainly affects feedlot calves. The involvement of Mycoplasma bovis in BRD can lead to chronic pneumonia poorly responsive to antimicrobial treatment. Caseonecrotic bronchopneumonia is a pulmonary lesion typically associated with M. bovis. In Spain, M. bovis is widely distributed in the feedlots and circulating isolates are resistant to most antimicrobials in vitro. However, the role of this species in clinical respiratory disease of feedlot calves remains unknown. Furthermore, available data are relative to a fixed panel of antimicrobials commonly used to treat BRD, but not to the specific set of antimicrobials that have been used for treating each animal. This study examined 23 feedlot calves raised in southeast Spain (2016–2019) with clinical signs of respiratory disease unresponsive to treatment. The presence of M. bovis was investigated through bacteriology (culture and subsequent PCR), histopathology and immunohistochemistry. The pathogen was found in 86.9% (20/23) of the calves, mainly in the lungs (78.26%; 18/23). Immunohistochemistry revealed M. bovis antigens in 73.9% (17/23) of the calves in which caseonecrotic bronchopneumonia was the most frequent lesion (16/17). Minimum inhibitory concentration assays confirmed the resistance of a selection of 12 isolates to most of the antimicrobials specifically used for treating the animals in vivo. These results stress the importance of M. bovis in the BRD affecting feedlot calves in Spain.

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