Immunogenicity and protective efficacy of a DNA vaccine inducing optimal expression of the SARS-CoV-2 S gene in hACE2 mice.

The wide spread of coronavirus disease 2019 (COVID-19) has significantly threatened public health. Human herd immunity induced by vaccination is essential to fight the epidemic. Therefore, highly immunogenic and safe vaccines are necessary to control SARS-CoV-2, whose S protein is the antigenic determinant responsible for eliciting antibodies that prevent viral entry and fusion. In this study, we developed a SARS-CoV-2 DNA vaccine expressing the S protein, named pVAX-S-OP, which was optimized according to the human-origin codon preference and using polyinosinic-polycytidylic acid as an adjuvant. pVAX-S-OP induced specific antibodies and neutralizing antibodies in BALB/c and hACE2 transgenic mice. Furthermore, we observed 1.43-fold higher antibody titers in mice receiving pVAX-S-OP plus adjuvant than in those receiving pVAX-S-OP alone. Interferon gamma production in the pVAX-S-OP-immunized group was 1.58 times (CD3+CD4+IFN-gamma+) and 2.29 times (CD3+CD8+IFN-gamma+) lower than that in the pVAX-S-OP plus adjuvant group but higher than that in the control group. The pVAX-S-OP vaccine was also observed to stimulate a Th1-type immune response. When, hACE2 transgenic mice were challenged with SARS-CoV-2, qPCR detection of N and E genes showed that the viral RNA loads in pVAX-S-OP-immunized mice lung tissues were 104 times and 106 times lower than those of the PBS control group, which shows that the vaccine could reduce the amount of live virus in the lungs of hACE2 mice. In addition, pathological sections showed less lung damage in the pVAX-S-OP-immunized group. Taken together, our results demonstrated that pVAX-S-OP has significant immunogenicity, which provides support for developing SARS-CoV-2 DNA candidate vaccines.

Retrospective analysis of influencing factors on the efficacy of mechanical ventilation in severe and critical COVID-19 patients.

BACKGROUND: The novel coronavirus disease 2019 (COVID-19) has spread widely around the world with strong infectivity, rapid mutation and a high mortality rate. Mechanical ventilation has been included in the Diagnosis and Treatment Protocol for Novel Coronavirus Pneumonia (Trial Version 8) as an important treatment for severe and critical COVID-19 patients, but its clinical efficacy in COVID-19 patients is various. Therefore, it is necessary to study the influencing factors on the efficacy of mechanical ventilation in severe and critical COVID-19 patients. AIM: The aim of this study was to determine the influencing factors on the efficacy of mechanical ventilation in severe and critical COVID-19 patients. METHODS: A total of 27 severe and critical COVID-19 patients were enrolled in this study and treated with mechanical ventilation at the Optical Valley Campus of Hubei Maternal and Child Health Care Hospital (Wuhan, Hubei Province) from February 20, 2020 to April 5, 2020. According to the final treatment outcomes, the patients were divided into the "effective group" and "death group." The clinical data of the two groups, such as the treatment process and final outcome, were retrospectively analyzed in order to determine the specific curative effects on the two groups and the reasons for the differences in such curative effects, as well as to explore the factors related to death. RESULTS: This study enrolled 27 severe and critical COVID-19 patients, including 17 males (63.0%) and 10 females (37.0%). Their ages were 74.41 ± 11.73-years-old, and 19 patients (70.4%) were over 70-years-old. Severe COVID-19 patients over 70-years-old who were treated with mechanical ventilation died in 14 cases (82.4%); thus, this was the peak age. A total of 17 patients died of basic disease, 16 of whom had more than two basic diseases. The basic diseases were hypertension, diabetes, and cardiovascular and cerebrovascular diseases. At the same time, 13 patients (76.5%) died from an abnormal increase in blood glucose. Among them, eight had diabetes before contracting COVID-19 and five had a stress-induced increase in blood glucose after contracting COVID-19. Diabetic ketoacidosis occurred in one case. The use of tocilizumab may be a double-edged sword that carries a certain risk in clinical usage. Among the patients who died, 16 (94.1%) went into septic shock at the end. There were significant differences in the degree of infection, cardiac and renal function, and blood glucose between the death group and effective group. CONCLUSION: Age, blood glucose, cardiac and renal function, and inflammatory reaction are important indicators of poor prognosis for mechanical ventilation in severe and critical COVID-19 patients.

Pan-cancer analysis of RNA expression of ANGIOTENSIN-I-CONVERTING ENZYME 2 reveals high variability and possible impact on COVID-19 clinical outcomes.

Patients with cancer demonstrate particularly poor outcomes from COVID-19. To provide information essential for understanding the biologic underpinnings of this association, we analyzed whole-transcriptome RNA expression data obtained from a large cohort of cancer patients to characterize expression of ACE2, TMPRSS2, and other proteases that are involved in viral attachment to and entry into target cells. We find substantial variability of expression of these factors across tumor types and identify subpopulations expressing ACE2 at very high levels. In some tumor types, especially in gastrointestinal cancers, expression of ACE2 and TMPRSS2 is highly correlated. Furthermore, we found infiltration with T-cell and natural killer (NK) cell infiltration to be particularly pronounced in ACE2-high tumors. These findings suggest that subsets of cancer patients exist with gene expression profiles that may be associated with heightened susceptibility to SARS-CoV-2 infection, in whom malignant tumors function as viral reservoir and possibly promote the frequently detrimental hyper-immune response in patients infected with this virus.

A Review on Deep Learning Techniques for the Diagnosis of Novel Coronavirus (COVID-19).

Novel coronavirus (COVID-19) outbreak, has raised a calamitous situation all over the world and has become one of the most acute and severe ailments in the past hundred years. The prevalence rate of COVID-19 is rapidly rising every day throughout the globe. Although no vaccines for this pandemic have been discovered yet, deep learning techniques proved themselves to be a powerful tool in the arsenal used by clinicians for the automatic diagnosis of COVID-19. This paper aims to overview the recently developed systems based on deep learning techniques using different medical imaging modalities like Computer Tomography (CT) and X-ray. This review specifically discusses the systems developed for COVID-19 diagnosis using deep learning techniques and provides insights on well-known data sets used to train these networks. It also highlights the data partitioning techniques and various performance measures developed by researchers in this field. A taxonomy is drawn to categorize the recent works for proper insight. Finally, we conclude by addressing the challenges associated with the use of deep learning methods for COVID-19 detection and probable future trends in this research area. The aim of this paper is to facilitate experts (medical or otherwise) and technicians in understanding the ways deep learning techniques are used in this regard and how they can be potentially further utilized to combat the outbreak of COVID-19.

Effect of a genetically engineered interferon-alpha versus traditional interferon-alpha in the treatment of moderate-to-severe COVID-19: a randomised clinical trial.

BACKGROUND: There are few effective therapies for coronavirus disease 2019 (COVID-19) upon the outbreak of the pandemic. To compare the effectiveness of a novel genetically engineered recombinant super-compound interferon (rSIFN-co) with traditional interferon-alpha added to baseline antiviral agents (lopinavir-ritonavir or umifenovir) for the treatment of moderate-to-severe COVID-19. METHOD: In this multicenter randomized (1:1) trial, patients hospitalized with moderate-to-severe COVID-19 received either rSIFN-co nebulization or interferon-alpha nebulization added to baseline antiviral agents for no more than 28 days. The primary endpoint was the time to clinical improvement. Secondary endpoints included the overall rate of clinical improvement assessed on day 28, the time to radiological improvement and virus nucleic acid negative conversion. RESULTS: A total of 94 patients were included in the safety set (46 patients assigned to rSIFN-co group, 48 to interferon-alpha group). The time to clinical improvement was 11.5 days versus 14.0 days (95% CI 1.10 to 2.81, p = .019); the overall rate of clinical improvement on day 28 was 93.5% versus 77.1% (difference, 16.4%; 95% CI 3% to 30%); the time to radiological improvement was 8.0 days versus 10.0 days (p = .002), the time to virus nucleic acid negative conversion was 7.0 days versus 10.0 days (p = .018) in the rSIFN-co and interferon alpha arms, respectively. Adverse events were balanced with no deaths among groups. CONCLUSIONS AND RELEVANCE: rSIFN-co was associated with a shorter time of clinical improvement than traditional interferon-alpha in the treatment of moderate-to-severe COVID-19 when combined with baseline antiviral agents. rSIFN-co therapy alone or combined with other antiviral therapy is worth to be further studied.Key messagesThere are few effective therapies for coronavirus disease 2019 (COVID-19) upon the outbreak of the pandemic. Interferon alphas, by inducing both innate and adaptive immune responses, have shown clinical efficacy in treating severe acute respiratory syndrome coronavirus and Middle East respiratory syndrome coronavirus.In this multicenter, head-to-head, randomized, clinical trial which included 94 participants with moderate-to-severe COVID-19, the rSIFN-co plus antiviral agents (lopinavir-ritonavir or umifenovir) was associated with a shorter time of clinical improvement than interferon-alpha plus antiviral agents.

Analysis of viral load in different specimen types and serum antibody levels of COVID-19 patients.

BACKGROUND: COVID-19 has caused a global pandemic and the death toll is increasing. However, there is no definitive information regarding the type of clinical specimens that is the best for SARS-CoV-2 detection, the antibody levels in patients with different duration of disease, and the relationship between antibody level and viral load. METHODS: Nasopharyngeal swabs, anal swabs, saliva, blood, and urine specimens were collected from patients with a course of disease ranging from 7 to 69 days. Viral load in different specimen types was measured using droplet digital PCR (ddPCR). Meanwhile, anti-nucleocapsid protein (anti-N) IgM and IgG antibodies and anti-spike protein receptor-binding domain (anti-S-RBD) IgG antibody in all serum samples were tested using ELISA. RESULTS: The positive detection rate in nasopharyngeal swab was the highest (54.05%), followed by anal swab (24.32%), and the positive detection rate in saliva, blood, and urine was 16.22%, 10.81%, and 5.41%, respectively. However, some patients with negative nasopharyngeal swabs had other specimens tested positive. There was no significant correlation between antibody level and days after symptoms onset or viral load. CONCLUSIONS: Other specimens could be positive in patients with negative nasopharyngeal swabs, suggesting that for patients in the recovery period, specimens other than nasopharyngeal swabs should also be tested to avoid false negative results, and anal swabs are recommended. The antibody level had no correlation with days after symptoms onset or the viral load of nasopharyngeal swabs, suggesting that the antibody level may also be affected by other factors.

Clinical efficacy of tocilizumab treatment in severe and critical COVID-19 patients.

BACKGROUND: The main pathophysiological basis of coronavirus disease 2019 (COVID-19) causing respiratory failure is a cytokine storm and interleukin-6 (IL-6) is an important component of the COVID-19 cytokine storm. As a specific antagonist of IL-6, tocilizumab may block the cytokine storm of COVID-19. The Diagnosis and Treatment Guidelines of New Coronavirus Pneumonia (7th Edition) includes tocilizumab as a recommended drug for immunotherapy in severe and critical COVID-19 patients. However, the specific clinical efficacy of tocilizumab in the treatment of COVID-19 patients is worth studying. AIM: To determine the clinical efficacy of tocilizumab in inhibiting the cytokine storm in COVID-19. METHODS: In total, 19 severe and critical COVID-19 patients were enrolled in this study, and were treated with tocilizumab in Optical Valley Campus of Hubei Maternal and Child Health Care Hospital from February 20 to March 31, 2020. The imaging manifestations and clinical data before and after treatment were analyzed retrospectively, including routine peripheral venous blood tests, routine blood biochemical tests, coagulation test, C-reactive protein (CRP), IL-6, and arterial blood gas analysis. RESULTS: Of the 19 patients in this group, 13 (68.4%) had significantly improved symptoms of COVID-19 (5 patients were discharged directly and 8 patients were transferred after improvement) following treatment. One case was invalid, 1 case was exacerbated, and 4 deaths (21.1%) were observed (all critical cases). The lymphocyte count, CRP, lactic acid, oxygenation index, fibrinogen (FIB) and IL-6 levels were significantly different in the improved group. CONCLUSION: Tocilizumab treatment is effective against IL-6 in COVID-19 patients, but it does not completely inhibit the inflammation and cytokine storm in all patients with COVID-19.In the clinical treatment of COVID-19 patients, attention should be paid to the timing of drug administration and other adjuvant treatments.

Cardiac manifestations of COVID-19 in Shenzhen, China.

PURPOSE: The coronavirus disease 2019 (COVID-19) outbreak has become a global public health concern; however, relatively few detailed reports of related cardiac injury are available. The aims of this study were to compare the clinical and echocardiographic characteristics of inpatients in the intensive-care unit (ICU) and non-ICU patients. METHODS: We recruited 416 patients diagnosed with COVID-19 and divided them into two groups: ICU (n = 35) and non-ICU (n = 381). Medical histories, laboratory findings, and echocardiography data were compared. RESULTS: The levels of myocardial injury markers in ICU vs non-ICU patients were as follows: troponin I (0.029 ng/mL [0.007-0.063] vs 0.006 ng/mL [0.006-0.006]) and myoglobin (65.45 µg/L [39.77-130.57] vs 37.00 µg/L [26.40-53.54]). Echocardiographic findings included ventricular wall thickening (12 [39%] vs 1 [4%]), pulmonary hypertension (9 [29%] vs 0 [0%]), and reduced left-ventricular ejection fraction (5 [16%] vs 0 [0%]). Overall, 10% of the ICU patients presented with right heart enlargement, thickened right-ventricular wall, decreased right heart function, and pericardial effusion. Cardiac complications were more common in ICU patients, including acute cardiac injury (21 [60%] vs 13 [3%]) (including 2 cases of fulminant myocarditis), atrial or ventricular tachyarrhythmia (3 [9%] vs 3 [1%]), and acute heart failure (5 [14%] vs 0 [0%]). CONCLUSION: Myocardial injury marker elevation, ventricular wall thickening, pulmonary artery hypertension, and cardiac complications including acute myocardial injury, arrhythmia, and acute heart failure are more common in ICU patients with COVID-19. Cardiac injury in COVID-19 patients may be related more to the systemic response after infection rather than direct damage by coronavirus.

First case of COVID-19 complicated with fulminant myocarditis: a case report and insights.

BACKGROUND: Coronavirus disease 2019 (COVID-19) has been demonstrated to be the cause of pneumonia. Nevertheless, it has not been reported as the cause of acute myocarditis or fulminant myocarditis. CASE PRESENTATION: A 63-year-old male was admitted with pneumonia and cardiac symptoms. He was genetically confirmed as having COVID-19 according to sputum testing on the day of admission. He also had elevated troponin I (Trop I) level (up to 11.37 g/L) and diffuse myocardial dyskinesia along with a decreased left ventricular ejection fraction (LVEF) on echocardiography. The highest level of interleukin-6 was 272.40 pg/ml. Bedside chest radiographs showed typical ground-glass changes indicative of viral pneumonia. Laboratory test results for viruses that cause myocarditis were all negative. The patient conformed to the diagnostic criteria of the Chinese expert consensus statement for fulminant myocarditis. After receiving antiviral therapy and mechanical life support, Trop I was reduced to 0.10 g/L, and interleukin-6 was reduced to 7.63 pg/mL. Moreover, the LVEF of the patient gradually recovered to 68%. The patient died of aggravation of secondary infection on the 33rd day of hospitalization. CONCLUSION: COVID-19 patients may develop severe cardiac complications such as myocarditis and heart failure. This is the first report of COVID-19 complicated with fulminant myocarditis. The mechanism of cardiac pathology caused by COVID-19 needs further study.