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1.
Front Immunol ; 13: 857440, 2022.
Article in English | MEDLINE | ID: covidwho-1817942

ABSTRACT

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has caused a worldwide pandemic. Here, we present non-human primate immunogenicity and protective efficacy data generated with the capsid virus-like particle (cVLP)-based vaccine ABNCoV2 that has previously demonstrated immunogenicity in mice. In rhesus macaques, a single vaccination with either 15 or 100 µg ABNCoV2 induced binding and neutralizing antibodies in a dose-dependent manner, at levels comparable to those measured in human convalescents. A second vaccine administration led to a >50-fold increase in neutralizing antibodies, with 2-log higher mean levels in the 100-µg ABNCoV2 group compared with convalescent samples. Upon SARS-CoV-2 challenge, a significant reduction in viral load was observed for both vaccine groups relative to the challenge control group, with no evidence of enhanced disease. Remarkably, neutralizing antibody titers against an original SARS-CoV-2 isolate and against variants of concern were comparable, indicating a potential for broad protection afforded by ABNCoV2, which is currently in clinical testing.


Subject(s)
COVID-19 , Viral Vaccines , Animals , Antibodies, Neutralizing , Antibodies, Viral , COVID-19/prevention & control , COVID-19 Vaccines , Capsid , Capsid Proteins , Humans , Macaca mulatta , SARS-CoV-2
2.
Viruses ; 14(4)2022 04 08.
Article in English | MEDLINE | ID: covidwho-1810316

ABSTRACT

SARS-CoV-2 causes acute respiratory disease, but many patients also experience neurological complications. Neuropathological changes with pronounced neuroinflammation have been described in individuals after lethal COVID-19, as well as in the CSF of hospitalized patients with neurological complications. To assess whether neuropathological changes can occur after a SARS-CoV-2 infection, leading to mild-to-moderate disease, we investigated the brains of four rhesus and four cynomolgus macaques after pulmonary disease and without overt clinical symptoms. Postmortem analysis demonstrated the infiltration of T-cells and activated microglia in the parenchyma of all infected animals, even in the absence of viral antigen or RNA. Moreover, intracellular α-synuclein aggregates were found in the brains of both macaque species. The heterogeneity of these manifestations in the brains indicates the virus' neuropathological potential and should be considered a warning for long-term health risks, following SARS-CoV-2 infection.


Subject(s)
COVID-19 , Encephalitis , alpha-Synuclein , Animals , Encephalitis/metabolism , Encephalitis/virology , Macaca mulatta/virology , Protein Aggregates , SARS-CoV-2 , alpha-Synuclein/metabolism
3.
Front Immunol ; 13: 845887, 2022.
Article in English | MEDLINE | ID: covidwho-1775679

ABSTRACT

Novel safe, immunogenic, and effective vaccines are needed to control the COVID-19 pandemic, caused by SARS-CoV-2. Here, we describe the safety, robust immunogenicity, and potent efficacy elicited in rhesus macaques by a modified vaccinia virus Ankara (MVA) vector expressing a full-length SARS-CoV-2 spike (S) protein (MVA-S). MVA-S vaccination was well tolerated and induced S and receptor-binding domain (RBD)-binding IgG antibodies and neutralizing antibodies against SARS-CoV-2 and several variants of concern. S-specific IFNγ, but not IL-4, -producing cells were also elicited. After SARS-CoV-2 challenge, vaccinated animals showed a significant strong reduction of virus loads in bronchoalveolar lavages (BAL) and decreased levels in throat and nasal mucosa. Remarkably, MVA-S also protected macaques from fever and infection-induced cytokine storm. Computed tomography and histological examination of the lungs showed reduced lung pathology in MVA-S-vaccinated animals. These findings favor the use of MVA-S as a potential vaccine for SARS-CoV-2 in clinical trials.


Subject(s)
COVID-19 , Vaccinia virus , Animals , Antibodies, Viral , COVID-19/prevention & control , COVID-19 Vaccines , Humans , Macaca mulatta , Pandemics , SARS-CoV-2/genetics , Spike Glycoprotein, Coronavirus , Vaccinia virus/genetics
4.
Viruses ; 13(8)2021 08 23.
Article in English | MEDLINE | ID: covidwho-1367929

ABSTRACT

The post-acute phase of SARS-CoV-2 infection was investigated in rhesus (Macaca mulatta) and cynomolgus macaques (Macaca fascicularis). During the acute phase of infection, SARS-CoV-2 was shed via the nose and throat, and viral RNA was occasionally detected in feces. This phase coincided with a transient change in systemic immune activation. Even after the alleged resolution of the infection, computed tomography (CT) and positron emission tomography (PET)-CT revealed pulmonary lesions and activated tracheobronchial lymph nodes in all animals. Post-mortem histological examination of the lung tissue revealed mostly marginal or resolving minimal lesions that were indicative of SARS-CoV-2 infection. Evidence for SARS-CoV-2-induced histopathology was also found in extrapulmonary tissue samples, such as conjunctiva, cervical, and mesenteric lymph nodes. However, 5-6 weeks after SARS-CoV-2 exposure, upon necropsy, viral RNA was still detectable in a wide range of tissue samples in 50% of the macaques and included amongst others the heart, the respiratory tract and surrounding lymph nodes, salivary gland, and conjunctiva. Subgenomic messenger RNA was detected in the lungs and tracheobronchial lymph nodes, indicative of ongoing virus replication during the post-acute phase. These results could be relevant for understanding the long-term consequences of COVID-19 in humans.


Subject(s)
COVID-19/pathology , COVID-19/virology , Lung/pathology , SARS-CoV-2/physiology , Animals , Antibodies, Viral/blood , COVID-19/immunology , Cytokines/blood , Disease Models, Animal , Humans , Lung/virology , Lymph Nodes/pathology , Lymph Nodes/physiopathology , Macaca fascicularis , Macaca mulatta , RNA, Messenger/analysis , RNA, Viral/analysis , Respiratory System/pathology , Respiratory System/virology , SARS-CoV-2/immunology , Virus Replication
5.
J Exp Med ; 218(7)2021 07 05.
Article in English | MEDLINE | ID: covidwho-1205513

ABSTRACT

Safe and effective coronavirus disease-19 (COVID-19) vaccines are urgently needed to control the ongoing pandemic. While single-dose vaccine regimens would provide multiple advantages, two doses may improve the magnitude and durability of immunity and protective efficacy. We assessed one- and two-dose regimens of the Ad26.COV2.S vaccine candidate in adult and aged nonhuman primates (NHPs). A two-dose Ad26.COV2.S regimen induced higher peak binding and neutralizing antibody responses compared with a single dose. In one-dose regimens, neutralizing antibody responses were stable for at least 14 wk, providing an early indication of durability. Ad26.COV2.S induced humoral immunity and T helper cell (Th cell) 1-skewed cellular responses in aged NHPs that were comparable to those in adult animals. Aged Ad26.COV2.S-vaccinated animals challenged 3 mo after dose 1 with a SARS-CoV-2 spike G614 variant showed near complete lower and substantial upper respiratory tract protection for both regimens. Neutralization of variants of concern by NHP sera was reduced for B.1.351 lineages while maintained for the B.1.1.7 lineage independent of Ad26.COV2.S vaccine regimen.


Subject(s)
Adenoviridae/immunology , Aging/immunology , COVID-19 Vaccines/immunology , COVID-19/immunology , SARS-CoV-2/immunology , Animals , Antibodies, Neutralizing/immunology , Body Temperature , Bronchoalveolar Lavage , CD4-Positive T-Lymphocytes/immunology , CD8-Positive T-Lymphocytes/immunology , COVID-19/prevention & control , COVID-19/virology , Dose-Response Relationship, Immunologic , Female , Immunity, Humoral , Kinetics , Lung/pathology , Lung/virology , Macaca mulatta , Male , Spike Glycoprotein, Coronavirus/metabolism , Treatment Outcome , Vaccination , Viral Load
6.
Nature ; 590(7845): 320-325, 2021 02.
Article in English | MEDLINE | ID: covidwho-953381

ABSTRACT

The expanding pandemic of coronavirus disease 2019 (COVID-19) requires the development of safe, efficacious and fast-acting vaccines. Several vaccine platforms are being leveraged for a rapid emergency response1. Here we describe the development of a candidate vaccine (YF-S0) for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) that uses live-attenuated yellow fever 17D (YF17D) vaccine as a vector to express a noncleavable prefusion form of the SARS-CoV-2 spike antigen. We assess vaccine safety, immunogenicity and efficacy in several animal models. YF-S0 has an excellent safety profile and induces high levels of SARS-CoV-2 neutralizing antibodies in hamsters (Mesocricetus auratus), mice (Mus musculus) and cynomolgus macaques (Macaca fascicularis), and-concomitantly-protective immunity against yellow fever virus. Humoral immunity is complemented by a cellular immune response with favourable T helper 1 polarization, as profiled in mice. In a hamster model2 and in macaques, YF-S0 prevents infection with SARS-CoV-2. Moreover, a single dose conferred protection from lung disease in most of the vaccinated hamsters within as little as 10 days. Taken together, the quality of the immune responses triggered and the rapid kinetics by which protective immunity can be attained after a single dose warrant further development of this potent SARS-CoV-2 vaccine candidate.


Subject(s)
COVID-19 Vaccines/immunology , COVID-19/immunology , COVID-19/prevention & control , Genetic Vectors/genetics , SARS-CoV-2/immunology , Vaccines, Attenuated/immunology , Yellow Fever Vaccine/genetics , Animals , COVID-19 Vaccines/administration & dosage , COVID-19 Vaccines/adverse effects , COVID-19 Vaccines/genetics , Cricetinae , Disease Models, Animal , Female , Glycosylation , Macaca fascicularis/genetics , Macaca fascicularis/immunology , Macaca fascicularis/virology , Male , Mesocricetus/genetics , Mesocricetus/immunology , Mesocricetus/virology , Mice , Safety , Spike Glycoprotein, Coronavirus/chemistry , Spike Glycoprotein, Coronavirus/genetics , Spike Glycoprotein, Coronavirus/immunology , Spike Glycoprotein, Coronavirus/metabolism , Vaccines, Attenuated/administration & dosage , Vaccines, Attenuated/adverse effects , Vaccines, Attenuated/genetics
8.
Curr Biol ; 30(18): R1014-R1018, 2020 09 21.
Article in English | MEDLINE | ID: covidwho-703973

ABSTRACT

Recently, a petition was offered to the European Commission calling for an immediate ban on animal testing. Although a Europe-wide moratorium on the use of animals in science is not yet possible, there has been a push by the non-scientific community and politicians for a rapid transition to animal-free innovations. Although there are benefits for both animal welfare and researchers, advances on alternative methods have not progressed enough to be able to replace animal research in the foreseeable future. This trend has led first and foremost to a substantial increase in the administrative burden and hurdles required to make timely advances in research and treatments for human and animal diseases. The current COVID-19 pandemic clearly highlights how much we actually rely on animal research. COVID-19 affects several organs and systems, and the various animal-free alternatives currently available do not come close to this complexity. In this Essay, we therefore argue that the use of animals is essential for the advancement of human and veterinary health.


Subject(s)
Animal Experimentation , Biomedical Research , Coronavirus Infections , Disease Models, Animal , Pandemics , Pneumonia, Viral , Animals , Betacoronavirus , COVID-19 , Humans , SARS-CoV-2
9.
Science ; 368(6494): 1012-1015, 2020 05 29.
Article in English | MEDLINE | ID: covidwho-71867

ABSTRACT

The current pandemic coronavirus, severe acute respiratory syndrome-coronavirus 2 (SARS-CoV-2), was recently identified in patients with an acute respiratory syndrome, coronavirus disease 2019 (COVID-19). To compare its pathogenesis with that of previously emerging coronaviruses, we inoculated cynomolgus macaques with SARS-CoV-2 or Middle East respiratory syndrome (MERS)-CoV and compared the pathology and virology with historical reports of SARS-CoV infections. In SARS-CoV-2-infected macaques, virus was excreted from nose and throat in the absence of clinical signs and detected in type I and II pneumocytes in foci of diffuse alveolar damage and in ciliated epithelial cells of nasal, bronchial, and bronchiolar mucosae. In SARS-CoV infection, lung lesions were typically more severe, whereas they were milder in MERS-CoV infection, where virus was detected mainly in type II pneumocytes. These data show that SARS-CoV-2 causes COVID-19-like disease in macaques and provides a new model to test preventive and therapeutic strategies.


Subject(s)
Betacoronavirus/pathogenicity , Coronavirus Infections/pathology , Coronavirus Infections/virology , Disease Models, Animal , Lung/pathology , Macaca fascicularis , Pneumonia, Viral/pathology , Pneumonia, Viral/virology , Aging , Animals , Betacoronavirus/isolation & purification , Betacoronavirus/physiology , COVID-19 , Female , Lung/virology , Middle East Respiratory Syndrome Coronavirus/isolation & purification , Middle East Respiratory Syndrome Coronavirus/physiology , Pandemics , Pulmonary Alveoli/pathology , Pulmonary Alveoli/virology , Respiratory System/pathology , Respiratory System/virology , SARS Virus/isolation & purification , SARS Virus/physiology , SARS-CoV-2 , Severe Acute Respiratory Syndrome/pathology , Severe Acute Respiratory Syndrome/virology , Virus Replication , Virus Shedding
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