Project description:Vaccines against SARS-CoV-2 are urgently required, but early development of vaccines against SARS-CoV-1 resulted in enhanced disease after vaccination. Careful assessment of this phenomena is warranted for vaccine development against SARS CoV-2. Here we report detailed immune profiling after ChAdOx1 nCoV-19 (AZD1222) and subsequent high dose challenge in two animal models of SARS-CoV-2 mediated disease. We demonstrate in rhesus macaques the lung pathology caused by SARS-CoV-2 mediated pneumonia is reduced by prior vaccination with ChAdOx1 nCoV-19 which induced neutralising antibody responses after a single intramuscular administration. In a second animal model, ferrets, ChAdOx1 nCoV-19 reduced both virus shedding and lung pathology. Antibody titre were boosted by a second dose. Data from these challenge models on the absence of enhanced disease and the detailed immune profiling, support the continued clinical evaluation of ChAdOx1 nCoV-19.
Project description:Here we profiled about 77000 single-nucleus transcriptomes of lung, liver, kidney, and cerebral cortex from rhesus macaques infected with SARS-CoV-2. Our work of multi-organ single-nucleus transcriptomic survey of SARS-CoV-2 infected animal model expanded our understanding of disease features and antiviral immune defects caused by the novel coronavirus at cellular and molecular level, which may facilitate the development of potential therapeutic intervention for COVID-19.
Project description:Containment of the SARS coronavirus (SCV) outbreak was accompanied by the rapid characterization of this new pathogen's genome sequence in 2003, encouraging the development of anti-SCV therapeutics using short interfering RNA (siRNA) inhibitors. A pair of siRNA duplexes identified as potent SCV inhibitors in vitro was evaluated for in vivo efficacy and safety in a rhesus macaque SARS model using intranasal administration with clinical viable delivery carrier in three dosing regimens. Observations of SCV-induced SARS-like symptoms, measurements of SCV RNA presence in the respiratory tract, microscopic inspections of lung histopathology, and immunohistochemistry sections from 21 tested macaques consistently demonstrated siRNA-mediated anti-SCV activity. The prophylactic and therapeutic efficacies resulted in relief of animals from SCV infection-induced fever, diminished SCV in upper airway and lung alveoli, and milder acute diffuse alveoli damage (DAD). The dosages of siRNA used, 10 to 40 mg/kg, did not show any sign of siRNA-induced toxicity. These results support that a clinical investigation of this anti-SARS siRNA therapeutic agent is warranted. The study also illustrates the capability of siRNA to enable a massive reduction in development time for novel targeted therapeutic agents. We detail a representative example of large-mammal siRNA use.
Project description:BACKGROUND:Hypoperfusion is associated with hyperfibrinolysis and early death from exsanguination, whereas tissue trauma is associated with hypofibrinolysis and delayed death from organ failure. We sought to elucidate the effects of injury patterns on fibrinolysis phenotypes using a nonhuman primate (NHP) model. METHODS:NHPs were randomized to three injury groups (n = 8/group): 60 minutes severe pressure-targeted controlled hemorrhagic shock (HS); HS + soft tissue injury (HS+); or HS + soft tissue injury + femur fracture (HS++). Animals were resuscitated and monitored for 360 minutes. Blood samples were collected at baseline, end-of-shock, end-of-resuscitation (EOR), and T = 360 minutes for assessments of: severity of shock (lactate) and coagulation via prothrombin time, partial thromboplastin time, D-dimer, fibrinogen, antithrombin-III, von Willebrand factor, and viscoelastic testing (ROTEM). Results are reported as mean ± SEM; statistics: two-way analysis of variance and t-tests (significance: p < 0.05). RESULTS:Blood loss, prothrombin time, partial thromboplastin time, antithrombin-III, fibrinogen, and von Willebrand factor were equivalent among groups and viscoelastic testing revealed few differences throughout the study. D-dimer increased approximately threefold, at EOR in the HS group, and at T = 360 minutes in the HS+ and HS++ groups (p < 0.05). At EOR, in the HS group compared with the HS+ and HS++ groups; the D-dimer-lactate ratio was twofold greater (2.2 ± 0.3 vs. 1.1 ± 0.3 and 1.1 ± 0.2, respectively; p < 0.05) and tissue factor-activated fibrin clot 30-minute lysis index was lower (98 ± 1% vs. 100 ± 0% and 100 ± 0%, respectively; p < 0.05). CONCLUSION:NHPs in HS exhibit acute suppression of fibrinolysis in the presence of tissue injury. Additional assessments to more comprehensively evaluate the mechanisms linking tissue injury with the observed fibrinolysis shutdown response are warranted.
Project description:Inactivated coronaviruses, including severe acute respiratory syndrome coronavirus 1 (SARS-CoV-1) and Middle East respiratory syndrome coronavirus (MERS-CoV), as potential vaccines have been reported to result in enhanced respiratory diseases (ERDs) in murine and nonhuman primate (NHP) pneumonia models after virus challenge, which poses great safety concerns of antibody-dependent enhancement (ADE) for the rapid wide application of inactivated SARS-CoV-2 vaccines in humans, especially when the neutralizing antibody levels induced by vaccination or initial infection quickly wane to nonneutralizing or subneutralizing levels over the time. With passive transfer of diluted postvaccination polyclonal antibodies to mimic the waning antibody responses after vaccination, we found that in the absence of cellular immunity, passive infusion of subneutralizing or nonneutralizing anti-SARS-CoV-2 antibodies could still provide some level of protection against infection upon challenge, and no low-level antibody-enhanced infection was observed. The anti-SARS-CoV-2 IgG-infused group and control group showed similar, mild to moderate pulmonary immunopathology during the acute phase of virus infection, and no evidence of vaccine-related pulmonary immunopathology enhancement was found. Typical immunopathology included elevated MCP-1, IL-8 and IL-33 in bronchoalveolar lavage fluid; alveolar epithelial hyperplasia; and exfoliated cells and mucus in bronchioles. Our results corresponded with the recent observations that no pulmonary immunology was detected in preclinical studies of inactivated SARS-CoV-2 vaccines in either murine or NHP pneumonia models or in large clinical trials and further supported the safety of inactivated SARS-CoV-2 vaccines.
Project description:Development of therapeutic agents for severe acute respiratory syndrome (SARS) viral infection using short interfering RNA (siRNA) inhibitors exemplifies a powerful new means to combat emerging infectious diseases. Potent siRNA inhibitors of SARS coronavirus (SCV) in vitro were further evaluated for efficacy and safety in a rhesus macaque (Macaca mulatta) SARS model using clinically viable delivery while comparing three dosing regimens. Observations of SARS-like symptoms, measurements of SCV RNA presence and lung histopathology and immunohistochemistry consistently showed siRNA-mediated anti-SARS efficacy by either prophylactic or therapeutic regimens. The siRNAs used provided relief from SCV infection-induced fever, diminished SCV viral levels and reduced acute diffuse alveoli damage. The 10-40 mg/kg accumulated dosages of siRNA did not show any sign of siRNA-induced toxicity. These results suggest that a clinical investigation is warranted and illustrate the prospects for siRNA to enable a massive reduction in development time for new targeted therapeutic agents.
Project description:BackgroundMyocardial injury has been identified as a common complication in patients with COVID-19. However, recent research has serious limitations, such as non-guideline definition of myocardial injury, heterogenicity of troponin sampling or very short-term follow-up. Using data from a large European cohort, we aimed to overcome these pitfalls and adequately characterize myocardial damage in COVID-19.MethodsConsecutive patients with confirmed SARS-CoV-2 infection and available high-sensitive troponin I (hs-TnI), from March 1st to April 20th, 2020 who completed at least 1-month follow-up or died, were studied.ResultsA total of 918 patients (mean age 63.2±15.5 years, 60.1% male) with a median follow-up of 57 (49-63) days were included. Of these, 190 (20.7%) fulfilled strict criteria for myocardial injury (21.1% chronic, 76.8% acute non-ischemic, 2.1% acute ischemic). Time from onset of symptoms to maximum hs-TnI was 11 (7-18) days. Thrombotic and bleeding events, arrhythmias, heart failure, need for mechanical ventilation and death were significantly more prevalent in patients with higher hs-TnI concentrations, even without fulfilling criteria for myocardial injury. hs-TnI was identified as an independent predictor of mortality [HR 2.52 (1.57-4.04) per 5-logarithmic units increment] after adjusting for multiple relevant covariates.ConclusionElevated hs-TnI is highly prevalent among patients with SARS-CoV-2 infection. Even mild elevations well below the 99th URL were significantly associated with higher rates of cardiac and non-cardiac complications, and higher mortality. Future research should address the role of serial hs-TnI assessment to improve COVID-19 prognostic stratification and clinical outcomes.
Project description:BackgroundMyocardial injury has been identified as a common complication in patients with COVID-19. However, recent research has serious limitations, such as non-guideline definition of myocardial injury, heterogenicity of troponin sampling or very short-term follow-up. Using data from a large European cohort, we aimed to overcome these pitfalls and adequately characterize myocardial damage in COVID-19.MethodsConsecutive patients with confirmed SARS-CoV-2 infection and available high-sensitive troponin I (hs-TnI), from March 1st to April 20th, 2020 who completed at least 1-month follow-up or died, were studied.ResultsA total of 918 patients (mean age 63.2 ± 15.5 years, 60.1% male) with a median follow-up of 57 (49-63) days were included. Of these, 190 (20.7%) fulfilled strict criteria for myocardial injury (21.1% chronic, 76.8% acute non-ischemic, 2.1% acute ischemic). Time from onset of symptoms to maximum hs-TnI was 11 (7-18) days. Thrombotic and bleeding events, arrhythmias, heart failure, need for mechanical ventilation and death were significantly more prevalent in patients with higher hs-TnI concentrations, even without fulfilling criteria for myocardial injury. hs-TnI was identified as an independent predictor of mortality [HR 2.52 (1.57-4.04) per 5-logarithmic units increment] after adjusting for multiple relevant covariates.ConclusionElevated hs-TnI is highly prevalent among patients with SARS-CoV-2 infection. Even mild elevations well below the 99th URL were significantly associated with higher rates of cardiac and non-cardiac complications, and higher mortality. Future research should address the role of serial hs-TnI assessment to improve COVID-19 prognostic stratification and clinical outcomes.
Project description:Coronavirus disease 2019 (COVID-19), caused by the SARS-CoV-2 virus, has had a dramatic global impact on public health and social and economic infrastructures. Here, we assess the immunogenicity and anamnestic protective efficacy in rhesus macaques of an intradermal (i.d.)-delivered SARS-CoV-2 spike DNA vaccine, INO-4800, currently being evaluated in clinical trials. Vaccination with INO-4800 induced T cell responses and induced spike antigen and RBD binding antibodies with ADCP and ADCD activity. Sera from the animals neutralized both the D614 and G614 SARS-CoV-2 pseudotype viruses. Several months after vaccination, animals were challenged with SARS-CoV-2 resulting in rapid recall of anti-SARS-CoV-2 spike protein T cell and neutralizing antibody responses. These responses were associated with lower viral loads in the lung. These studies support the immune impact of INO-4800 for inducing both humoral and cellular arms of the adaptive immune system, which are likely important for providing durable protection against COVID-19 disease.