COVID-19 spike polypeptide vaccine reduces the pathogenesis and viral infection in a mouse model of SARS-CoV-2

The SARS-CoV-2 coronavirus, which causes a respiratory disease called COVID-19, has been declared a pandemic by the World Health Organization (WHO) and is still ongoing. Vaccination is the most important strategy to end the pandemic. Several vaccines have been approved, as evidenced by the ongoing global pandemic, but the pandemic is far from over and no fully effective vaccine is yet available. One of the most critical steps in vaccine development is the selection of appropriate antigens and their proper introduction into the immune system. Therefore, in this study, we developed and evaluated two proposed vaccines composed of single and multiple SARS-CoV-2 polypeptides derived from the spike protein, namely, vaccine A and vaccine B, respectively. The polypeptides were validated by the sera of COVID-19-vaccinated individuals and/or naturally infected COVID-19 patients to shortlist the starting pool of antigens followed by in vivo vaccination to hACE2 transgenic mice. The spike multiple polypeptide vaccine (vaccine B) was more potent to reduce the pathogenesis of organs, resulting in higher protection against the SARS-CoV-2 infection.

COVID-19 spike polypeptide vaccine reduces the pathogenesis and viral infection in a mouse model of SARS-CoV-2.

The SARS-CoV-2 coronavirus, which causes a respiratory disease called COVID-19, has been declared a pandemic by the World Health Organization (WHO) and is still ongoing. Vaccination is the most important strategy to end the pandemic. Several vaccines have been approved, as evidenced by the ongoing global pandemic, but the pandemic is far from over and no fully effective vaccine is yet available. One of the most critical steps in vaccine development is the selection of appropriate antigens and their proper introduction into the immune system. Therefore, in this study, we developed and evaluated two proposed vaccines composed of single and multiple SARS-CoV-2 polypeptides derived from the spike protein, namely, vaccine A and vaccine B, respectively. The polypeptides were validated by the sera of COVID-19-vaccinated individuals and/or naturally infected COVID-19 patients to shortlist the starting pool of antigens followed by in vivo vaccination to hACE2 transgenic mice. The spike multiple polypeptide vaccine (vaccine B) was more potent to reduce the pathogenesis of organs, resulting in higher protection against the SARS-CoV-2 infection.

SARS-CoV-2 Omicron Mutation Is Faster than the Chase: Multiple Mutations on Spike/ACE2 Interaction Residues.

Recently, a new severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) (B.1.1.529) Omicron variant originated from South Africa in the middle of November 2021. SARS-CoV-2 is also called coronavirus disease 2019 (COVID-19) since SARS-CoV-2 is the causative agent of COVID-19. Several studies already suggested that the SARS-CoV-2 Omicron variant would be the fastest transmissible variant compared to the previous 10 SARS-CoV-2 variants of concern, interest, and alert. Few clinical studies reported the high transmissibility of the Omicron variant but there is insufficient time to perform actual experiments to prove it, since the spread is so fast. We analyzed the SARS-CoV-2 Omicron variant, which revealed a very high rate of mutation at amino acid residues that interact with angiostatin-converting enzyme 2. The mutation rate of COVID-19 is faster than what we prepared vaccine program, antibody therapy, lockdown, and quarantine against COVID-19 so far. Thus, it is necessary to find better strategies to overcome the current crisis of COVID-19 pandemic.

Clinical impact of blood pressure variability in patients with COVID-19 and hypertension.

OBJECTIVE: This study aimed to investigate the relationship between blood pressure variability (BPV) and clinical outcomes in patients with coronavirus disease 2019 (COVID-19) and hypertension. METHODS: A total of 136 patients hospitalized with COVID-19 were enrolled in this study. Patients were grouped according to the presence of hypertension and BPV. Mean arterial pressure (MAP) measured at 8 a.m. and 8 p.m. was analyzed, and BPV was calculated as the coefficient of variation of MAP (MAPCV). High BPV was defined as MAPCV values above the median. We compared the age, level of C-reactive protein (CRP), creatine kinase-MB (CK-MB), N-terminal pro-B type natriuretic peptide (NT-proBNP), creatinine and in-hospital mortality and investigated the relationship among the groups. RESULTS: COVID-19 patients with hypertension were older (70 ± 12 vs. 53 ± 17 years; P < 0.001), had higher levels of CRP (9.4 ± 9.2 vs. 5.3 ± 8.2 mg/dL; P = 0.009), MAPCV (11.4 ± 4.8 vs. 8.9 ± 3.2; P = 0.002), and higher in-hospital mortality (19.6% vs. 5.9%; P = 0.013) than those without hypertension. There was a proportional relationship between BPV and age, levels of CRP, CK-MB, NT-proBNP, creatinine and in-hospital mortality (all, P < 0.05). In Cox regression analysis, advanced age [≥80 years, hazard ratio (HR) 10.4, 95% confidence interval (CI) 2.264-47.772, P = 0.003] and higher MAPCV (HR 1.617, 95% CI, 1.281-2.040, P < 0.001) were significantly associated with in-hospital mortality. CONCLUSION: High BPV in COVID-19 patients with hypertension is significantly associated with in-hospital mortality. Advanced age and systemic inflammation are proportional to high BPV. Additional attention is needed for COVID-19 patients with hypertension and high BPV.

Experience of Treating Critically Ill COVID-19 Patients in Daegu, South Korea.

At the beginning of February 2020, Daegu faced a serious situation due to the rapid outbreak of coronavirus disease 2019 (COVID-19), which is caused by severe acute respiratory syndrome coronavirus-2. The healthcare system in Daegu Metropolitan City was ill-prepared for this sudden disaster situation. The COVID-19 pandemic is still ongoing in South Korea. Daegu has limited medical resources compared to the Seoul Metropolitan Area, and it is hypothesized that a review of the outbreak therein could provide information that will be valuable for dealing with future outbreaks. The likelihood of death due to COVID-19 depends on the capacity of the area for the treatment of critically ill patients. This report reviews the overall treatment process followed for critically ill patients in Daegu.

Clinical features and prognostic factors of critically ill patients with COVID-19 in Daegu, South Korea: A multi-center retrospective study.

ABSTRACT: To describe the clinical and demographic characteristics of critically ill patients with COVID-19 in Daegu, South Korea, and to explore the risk factors for in-hospital mortality in these patients.Retrospective cohort study of 110 critically ill patients with COVID-19 admitted to the ICU in Daegu, South Korea, between February 18 and April 5, 2020. The final date of follow-up was April 20, 2020.A total of 110 patient medical records were reviewed. The median age was 71 years (interquartile range [IQR] = 63-78 years). During the study period, 47 patients (42.7%) died in the hospital. The most common SARS-CoV-2 infection related complication was acute respiratory distress syndrome (ARDS) in 95 patients (86.4%). Of the 79 patients (71.8%) who received invasive mechanical ventilation, 46 (58.2%) received neuromuscular blockade injection, and 19 (24.1%) received ECMO treatment. All patients received antibiotic injection, 99 patients (90%) received hydroxychloroquine, 96 patients (87.3%) received lopinavir-ritonavir antiviral medication, and 14 patients (12.7%) received other antiviral agents, including darunavir-cobicistat and emtricitabine-tenofovir. In the multivariable logistic regression model, the odds ratio of in-hospital death was higher with APACHE II score (OR = 1.126; 95% CI = 1.014-1.252; P  = .027).The in-hospital mortality rate of critically ill patients with COVID-19 was approximately 40%. Higher APACHE II score at admission was an independent risk factor for death in these patients.

Quantitative Assessment of Chest CT Patterns in COVID-19 and Bacterial Pneumonia Patients: a Deep Learning Perspective.

BACKGROUND: It is difficult to distinguish subtle differences shown in computed tomography (CT) images of coronavirus disease 2019 (COVID-19) and bacterial pneumonia patients, which often leads to an inaccurate diagnosis. It is desirable to design and evaluate interpretable feature extraction techniques to describe the patient's condition. METHODS: This is a retrospective cohort study of 170 confirmed patients with COVID-19 or bacterial pneumonia acquired at Yeungnam University Hospital in Daegu, Korea. The Lung and lesion regions were segmented to crop the lesion into 2D patches to train a classifier model that could differentiate between COVID-19 and bacterial pneumonia. The K-means algorithm was used to cluster deep features extracted by the trained model into 20 groups. Each lesion patch cluster was described by a characteristic imaging term for comparison. For each CT image containing multiple lesions, a histogram of lesion types was constructed using the cluster information. Finally, a Support Vector Machine classifier was trained with the histogram and radiomics features to distinguish diseases and severity. RESULTS: The 20 clusters constructed from 170 patients were reviewed based on common radiographic appearance types. Two clusters showed typical findings of COVID-19, with two other clusters showing typical findings related to bacterial pneumonia. Notably, there is one cluster that showed bilateral diffuse ground-glass opacities (GGOs) in the central and peripheral lungs and was considered to be a key factor for severity classification. The proposed method achieved an accuracy of 91.2% for classifying COVID-19 and bacterial pneumonia patients with 95% reported for severity classification. The CT quantitative parameters represented by the values of cluster 8 were correlated with existing laboratory data and clinical parameters. CONCLUSION: Deep chest CT analysis with constructed lesion clusters revealed well-known COVID-19 CT manifestations comparable to manual CT analysis. The constructed histogram features improved accuracy for both diseases and severity classification, and showed correlations with laboratory data and clinical parameters. The constructed histogram features can provide guidance for improved analysis and treatment of COVID-19.

The Progression of SARS Coronavirus 2 (SARS-CoV2): Mutation in the Receptor Binding Domain of Spike Gene.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV2) is a positive-sense single-stranded RNA (+ssRNA) that causes coronavirus disease 2019 (COVID-19). The viral genome encodes twelve genes for viral replication and infection. The third open reading frame is the spike (S) gene that encodes for the spike glycoprotein interacting with specific cell surface receptor - angiotensin converting enzyme 2 (ACE2) - on the host cell membrane. Most recent studies identified a single point mutation in S gene. A single point mutation in S gene leading to an amino acid substitution at codon 614 from an aspartic acid 614 into glycine (D614G) resulted in greater infectivity compared to the wild type SARS-CoV2. We were interested in investigating the mutation region of S gene of SARS-CoV2 from Korean COVID-19 patients. New mutation sites were found in the critical receptor binding domain (RBD) of S gene, which is adjacent to the aforementioned D614G mutation residue. This specific sequence data demonstrated the active progression of SARS-CoV2 by mutations in the RBD of S gene. The sequence information of new mutations is critical to the development of recombinant SARS-CoV2 spike antigens, which may be required to improve and advance the strategy against a wide range of possible SARS-CoV2 mutations.

The Risk of Diabetes on Clinical Outcomes in Patients with Coronavirus Disease 2019: A Retrospective Cohort Study.

BACKGROUND: To determine the role of diabetes mellitus (DM) in the coronavirus disease 2019 (COVID-19), we explored the clinical characteristics of patients with DM and compared risk factors such as age, glycemic control, and medications to those without DM. METHODS: This was a retrospective cohort study of 117 confirmed patients with COVID-19 which conducted at a tertiary hospital in Daegu, South Korea. The primary outcome was defined as the severe and critical outcome (SCO), of which the composite outcomes of acute respiratory distress syndrome, septic shock, intensive care unit care, and 28-day mortality. We analyzed what clinical features and glycemic control-related factors affect the prognosis of COVID-19 in the DM group. RESULTS: After exclusion, 110 participants were finally included. DM patients (n=29) was older, and showed higher blood pressure compared to non-DM patients. DM group showed higher levels of inflammation-related biomarkers and severity score, and highly progressed to SCO. After adjustment with other risk factors, DM increased the risk of SCO (odds ratio [OR], 10.771; P<0.001). Among the DM patients, SCO was more prevalent in elderly patients of ≥70 years old and age was an independent risk factor for SCO in patients with DM (OR, 1.175; P=0.014), while glycemic control was not. The use of medication did not affect the SCO, but the renin-angiotensin system inhibitors showed protective effects against acute cardiac injury (OR, 0.048; P=0.045). CONCLUSION: The COVID-19 patients with DM had higher severity and resulted in SCO. Intensive and aggressive monitoring of COVID-19 clinical outcomes in DM group, especially in elderly patients is warranted.

Clinical Features and Outcomes of 98 Patients Hospitalized with SARS-CoV-2 Infection in Daegu, South Korea: A Brief Descriptive Study.

Although some information on the epidemiology of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and a few selected cases has been reported, data on the clinical characteristics and outcomes of patients hospitalized therewith in South Korea are lacking. We conducted a retrospective single-center study of 98 consecutive hospitalized patients with confirmed SARS-CoV-2 infection at Yeungnam University Medical Center in Daegu, South Korea. Sixty patients were women (61.2%), and the mean age was 55.4±17.1 years. Thirteen patients (13.3%) were treated in the intensive care unit (ICU). The mean interval from symptom onset to hospitalization was 7.7±4.5 days. Patients who received ICU care were significantly older and were more likely to have diabetes mellitus. The National Early Warning Score on the day of admission was significantly higher in patients requiring ICU care. Acute respiratory distress syndrome (13/13 patients; 100%), septic shock (9/13; 69.2%), acute cardiac injury (9/13; 69.2%), and acute kidney injury (8/13; 61.5%) were more common in patients who received ICU care. All patients received antibiotic therapy, and most (97/98 patients; 99.0%) received antiviral therapy (lopinavir/ritonavir). Hydroxychloroquine was used in 79 patients (80.6%), and glucocorticoid therapy was used in 18 patients (18.4%). In complete blood counts, lymphopenia was the most common finding (40/98 patients; 40.8%). Levels of all proinflammatory cytokines were significantly higher in ICU patients. As of March 29, 2020, the mortality rate was 5.1%. Here, we report the clinical characteristics and laboratory findings of SARS-CoV-2 patients in South Korea up to March 29, 2020.