Preventive and therapeutic benefits of nelfinavir in rhesus macaques and human beings infected with SARS-CoV-2.

Effective drugs with broad spectrum safety profile to all people are highly expected to combat COVID-19 caused by SARS-CoV-2. Here we report that nelfinavir, an FDA approved drug for the treatment of HIV infection, is effective against SARS-CoV-2 and COVID-19. Preincubation of nelfinavir could inhibit the activity of the main protease of the SARS-CoV-2 (IC50 = 8.26 µM), while its antiviral activity in Vero E6 cells against a clinical isolate of SARS-CoV-2 was determined to be 2.93 µM (EC50). In comparison with vehicle-treated animals, rhesus macaque prophylactically treated with nelfinavir had significantly lower temperature and significantly reduced virus loads in the nasal and anal swabs of the animals. At necropsy, nelfinavir-treated animals had a significant reduction of the viral replication in the lungs by nearly three orders of magnitude. A prospective clinic study with 37 enrolled treatment-naive patients at Shanghai Public Health Clinical Center, which were randomized (1:1) to nelfinavir and control groups, showed that the nelfinavir treatment could shorten the duration of viral shedding by 5.5 days (9.0 vs. 14.5 days, P = 0.055) and the duration of fever time by 3.8 days (2.8 vs. 6.6 days, P = 0.014) in mild/moderate COVID-19 patients. The antiviral efficiency and clinical benefits in rhesus macaque model and in COVID-19 patients, together with its well-established good safety profile in almost all ages and during pregnancy, indicated that nelfinavir is a highly promising medication with the potential of preventative effect for the treatment of COVID-19.

Insomnia plays a key role in mental health problems of COVID-19 patients in Square Cabin Hospitals: a network analysis (preprint)

Background: While the emergence of the Coronavirus Disease 2019 (COVID-19) has greatly affected the mental health and wellbeing of people everywhere, the core symptoms of common syndromes of psychological distress remain unclear, especially among COVID-19 patients who have been quarantined in Square Cabin Hospitals. Using the method of network analysis, the current study explored the relations between stress, depression, anxiety and insomnia symptoms among COVID-19 patients in Shanghai Four-Leaf Clover Cabin Hospital. Method: The study used an online survey to gauge the mental health issues of COVID-19 patients at Shanghai Four-Leaf Clover Cabin Hospital from April 18 to May 19, 2022. The Perceived Stress Scale, Patient Health Questionnaire, Generalized Anxiety Disorder Scale, and Insomnia Severity Index were used to assess perceived stress symptoms, depressive symptoms, anxiety symptoms, and insomnia symptoms, respectively. The central symptoms and bridge symptoms were determined using a regularized partial correlation network. Results: A total of 1014 patients was included in this study. Overall, 61.5%, 49.2% , and 56.1% of all patients reported symptoms of depressive, anxiety, and insomnia, respectively. “Distress caused by the sleep difficulties” had the highest expected influence, followed by “Excessive worry”, “Severity of sleep onset”, “Overburden”, “Uncontrollable worry”, “Trouble relaxing”, “Restlessness”. Seven bridge symptoms were identified: “Sad Mood”, “Severity of sleep onset”, “Sleep”, “Motor”, “Feeling afraid”, “Nervousness”, “Appetite”. In addition, significant differences in network global strength were found between women and men. Conclusions: Psychological distress was prevalent among COVID-19 patients and insomnia symptoms played a key role in the network of psychological distress symptoms. As a result, specific insomnia symptoms should be closely monitored as potential intervention targets in alleviating or preventing common, frequently co-occurring psychiatric syndromes.

Single-nucleus transcriptomic profiling of multiple organs in a rhesus macaque model of SARS-CoV-2 infection.

Infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) causes diverse clinical manifestations and tissue injuries in multiple organs. However, cellular and molecular understanding of SARS-CoV-2 infection-associated pathology and immune defense features in different organs remains incomplete. Here, we profiled approximately 77 000 single-nucleus transcriptomes of the lung, liver, kidney, and cerebral cortex in rhesus macaques ( Macaca mulatta) infected with SARS-CoV-2 and healthy controls. Integrated analysis of the multi-organ dataset suggested that the liver harbored the strongest global transcriptional alterations. We observed prominent impairment in lung epithelial cells, especially in AT2 and ciliated cells, and evident signs of fibrosis in fibroblasts. These lung injury characteristics are similar to those reported in patients with coronavirus disease 2019 (COVID-19). Furthermore, we found suppressed MHC class I/II molecular activity in the lung, inflammatory response in the liver, and activation of the kynurenine pathway, which induced the development of an immunosuppressive microenvironment. Analysis of the kidney dataset highlighted tropism of tubule cells to SARS-CoV-2, and we found membranous nephropathy (an autoimmune disease) caused by podocyte dysregulation. In addition, we identified the pathological states of astrocytes and oligodendrocytes in the cerebral cortex, providing molecular insights into COVID-19-related neurological implications. Overall, our multi-organ single-nucleus transcriptomic survey of SARS-CoV-2-infected rhesus macaques broadens our understanding of disease features and antiviral immune defects caused by SARS-CoV-2 infection, which may facilitate the development of therapeutic interventions for COVID-19.

How does growth mindset affect mental health of high school students during the COVID-19 epidemic? The role of grit and coping strategies

Background The outbreak of COVID-19 epidemic continues to unfold globally, which harms the public’s mental health. Adolescents’ mental health is affected by social isolation and lockdown during the COVID-19 epidemic. The implicit theory of thoughts-emotion-behavior states that individuals with a growth mindset believe that thoughts, emotions, and behaviors can be changed through effort and tend to persist in pursuing higher goals and maintain enthusiasm as well as cope with stress resiliently, thus having higher gritty and levels of mental health. This study aimed to explore the role of grit and coping strategies in the influence of the growth mindset on adolescents’ mental health during the COVID-19 epidemic period. Methods A total of 1564 participants (Mage = 17.02, 760 boys, 804 girls) from three high schools in China were recruited to complete The Self-report Questionnaire-20, The Growth Mindset Scale, The Short Grit Scale, and The Coping Style Scale to evaluate mental health, growth mindset, grit, and positive coping strategies, respectively. Results The results showed that growth mindset has no significant indirect effect on mental health through grit but has a significant indirect effect on mental health through coping strategies. The results of chain mediation analysis showed that grit and coping strategies play chain mediating roles between growth mindset and adolescents’ mental health. Conclusion The findings suggest that cultivating a growth mindset, developing grit, and teaching adolescents to adopt positive coping strategies can improve adolescents’ mental health.

A tandem-repeat dimeric RBD protein-based covid-19 vaccine zf2001 protects mice and nonhuman primates.

Safe, efficacious, and deployable vaccines are urgently needed to control COVID-19 in the large-scale vaccination campaigns. We report here the preclinical studies of an approved protein subunit vaccine against COVID-19, ZF2001, which contains tandem-repeat dimeric receptor-binding domain (RBD) protein with alum-based adjuvant. We assessed vaccine immunogenicity and efficacy in both mice and non-human primates (NHPs). ZF2001 induced high levels of RBD-binding and SARS-CoV-2 neutralizing antibody in both mice and non-human primates, and elicited balanced TH1/TH2 cellular responses in NHPs. Two doses of ZF2001 protected Ad-hACE2-transduced mice against SARS-CoV-2 infection, as detected by reduced viral RNA and relieved lung injuries. In NHPs, vaccination of either 25 µg or 50 µg ZF2001 prevented infection with SARS-CoV-2 in lung, trachea, and bronchi, with milder lung lesions. No evidence of disease enhancement was observed in both animal models. ZF2001 has been approved for emergency use in China, Uzbekistan, Indonesia, and Columbia. The high safety, immunogenicity, and protection efficacy in both mice and NHPs found in this preclinical study was consistent with the results in human clinical trials.

CoVac501, a self-adjuvanting peptide vaccine conjugated with TLR7 agonists, against SARS-CoV-2 induces protective immunity.

Safe, effective, and economical vaccines against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) are needed to achieve adequate herd immunity and end the pandemic. We constructed a novel SARS-CoV-2 vaccine, CoVac501, which is a self-adjuvanting peptide vaccine conjugated with Toll-like receptor 7 (TLR7) agonists. The vaccine contains immunodominant peptides screened from the receptor-binding domain (RBD) and is fully chemically synthesized. It has been formulated in an optimized nanoemulsion formulation and is stable at 40 °C for 1 month. In non-human primates (NHPs), CoVac501 elicited high and persistent titers of protective neutralizing antibodies against multiple RBD mutations, SARS-CoV-2 original strain, and variants (B.1.1.7 and B.1.617.2). Specific peptides booster immunization against the B.1.351 variant has also been shown to be effective in improving protection against B.1.351. Meanwhile, CoVac501 elicited the increase of memory T cells, antigen-specific CD8+ T-cell responses, and Th1-biased CD4+ T-cell immune responses in NHPs. Notably, at an extremely high SARS-CoV-2 challenge dose of 1 × 107 TCID50, CoVac501 provided near-complete protection for the upper and lower respiratory tracts of cynomolgus macaques.

Self-assembling short immunostimulatory duplex RNAs with broad spectrum antiviral activity (preprint)

The current COVID-19 pandemic highlights the need for broad-spectrum antiviral therapeutics. Here we describe a new class of self-assembling immunostimulatory short duplex RNAs that potently induce production of type I and type III interferon (IFN-I and IFN-III), in a wide range of human cell types. These RNAs require a minimum of 20 base pairs, lack any sequence or structural characteristics of known immunostimulatory RNAs, and instead require a unique conserved sequence motif (sense strand: 5'-C, antisense strand: 3'-GGG) that mediates end-to-end dimer self-assembly of these RNAs by Hoogsteen G-G base-pairing. The presence of terminal hydroxyl or monophosphate groups, blunt or overhanging ends, or terminal RNA or DNA bases did not affect their ability to induce IFN. Unlike previously described immunostimulatory siRNAs, their activity is independent of TLR7/8, but requires the RIG-I/IRF3 pathway that induces a more restricted antiviral response with a lower proinflammatory signature compared with poly(I:C). Immune stimulation mediated by these duplex RNAs results in broad spectrum inhibition of infections by many respiratory viruses with pandemic potential, including SARS-CoV-2, SARS-CoV, MERS-CoV, and influenza A, as well as the common cold virus HCoV-NL63 in both cell lines and human Lung Chips that mimic organ-level lung pathophysiology. These short dsRNAs can be manufactured easily, and thus potentially could be harnessed to produce broad-spectrum antiviral therapeutics at low cost.

A pathogen-like antigen-based vaccine confers immune protection against SARS-CoV-2 in non-human primates.

Activation of nucleic acid sensing Toll-like receptors (TLRs) in B cells is involved in antiviral responses by promoting B cell activation and germinal center responses. In order to take advantage of this natural pathway for vaccine development, synthetic pathogen-like antigens (PLAs) constructed of multivalent antigens with encapsulated TLR ligands can be used to activate B cell antigen receptors and TLRs in a synergistic manner. Here we report a PLA-based coronavirus disease 2019 (COVID-19) vaccine candidate designed by combining a phage-derived virus-like particle carrying bacterial RNA as TLR ligands with the receptor-binding domain of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) S protein as the target antigen. This PLA-based vaccine candidate induces robust neutralizing antibodies in both mice and non-human primates (NHPs). Using a NHP infection model, we demonstrate that the viral clearance is accelerated in vaccinated animals. In addition, the PLA-based vaccine induces a T helper 1 (Th1)-oriented response and a durable memory, supporting its potential for further clinical development.

COVID-19 Pandemic: The Interplay Between Firm Disruption and Managerial Attention Focus

Abstract Pandemics and epidemics occur regularly, yet their impact on firm behaviours is under-researched. COVID-19 provides a unique opportunity to examine the impact of a once-in-a-century pandemic ? given its scope, swift spread, health and economic devastation ? on firms? behaviours. Attention is the critical and initial step of the environmental adaptation process. In this paper, we draw on two complementary theories ? contingency and attention-based view ? and examine the relationship between disruption experienced by firms and their COVID-19 attention focus ? a sudden exogenous shock. Industry environments may influence which signals attract managerial attention;hence, we examine if firm disruption?COVID-19 attention focus is moderated by industry dynamism. Drawing on the publicly available data and using a sample of 1,861 US and 1,154 Chinese firms ? two diametrically opposite situational contexts ? we test the generalizability of our hypotheses. We find a positive relationship between firm disruption and COVID-19 attention focus for the US sample and that industry dynamism negatively moderates this relationship. In the case of Chinese firms, these relationships were insignificant. Further analysis using topic modelling revealed that business?government relationships accounted for this difference.

Pro-inflammatory microenvironment and systemic accumulation of CXCR3+ cell exacerbate lung pathology of old rhesus macaques infected with SARS-CoV-2.

Understanding the pathological features of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection in an animal model is crucial for the treatment of coronavirus disease 2019 (COVID-19). Here, we compared immunopathological changes in young and old rhesus macaques (RMs) before and after SARS-CoV-2 infection at the tissue level. Quantitative analysis of multiplex immunofluorescence staining images of formalin-fixed paraffin-embedded (FFPE) sections showed that SARS-CoV-2 infection specifically induced elevated levels of apoptosis, autophagy, and nuclear factor kappa-B (NF-κB) activation of angiotensin-converting enzyme 2 (ACE2)+ cells, and increased interferon α (IFN-α)- and interleukin 6 (IL-6)-secreting cells and C-X-C motif chemokine receptor 3 (CXCR3)+ cells in lung tissue of old RMs. This pathological pattern, which may be related to the age-related pro-inflammatory microenvironment in both lungs and spleens, was significantly correlated with the systemic accumulation of CXCR3+ cells in lungs, spleens, and peripheral blood. Furthermore, the ratio of CXCR3+ to T-box protein expression in T cell (T-bet)+ (CXCR3+/T-bet+ ratio) in CD8+ cells may be used as a predictor of severe COVID-19. These findings uncovered the impact of aging on the immunopathology of early SARS-CoV-2 infection and demonstrated the potential application of CXCR3+ cells in predicting severe COVID-19.

Interferon-armed RBD dimer enhances the immunogenicity of RBD for sterilizing immunity against SARS-CoV-2.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has caused a global crisis, urgently necessitating the development of safe, efficacious, convenient-to-store, and low-cost vaccine options. A major challenge is that the receptor-binding domain (RBD)-only vaccine fails to trigger long-lasting protective immunity if used alone for vaccination. To enhance antigen processing and cross-presentation in draining lymph nodes (DLNs), we developed an interferon (IFN)-armed RBD dimerized by an immunoglobulin fragment (I-R-F). I-R-F efficiently directs immunity against RBD to DLNs. A low dose of I-R-F induces not only high titers of long-lasting neutralizing antibodies (NAbs) but also more comprehensive T cell responses than RBD. Notably, I-R-F provides comprehensive protection in the form of a one-dose vaccine without an adjuvant. Our study shows that the pan-epitope modified human I-R-F (I-P-R-F) vaccine provides rapid and complete protection throughout the upper and lower respiratory tracts against a high-dose SARS-CoV-2 challenge in rhesus macaques. Based on these promising results, we have initiated a randomized, placebo-controlled, phase I/II trial of the human I-P-R-F vaccine (V-01) in 180 healthy adults, and the vaccine appears safe and elicits strong antiviral immune responses. Due to its potency and safety, this engineered vaccine may become a next-generation vaccine candidate in the global effort to overcome COVID-19.

Particulate matter exposure exacerbates susceptibility to SARS-CoV-2 infection in humanized ACE2 mice.

The global outbreak of coronavirus disease 2019 (COVID-19), which is caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), as of 8 May 2021, has surpassed 150 700 000 infections and 3 279 000 deaths worldwide. Evidence indicates that SARS-CoV-2 RNA can be detected on particulate matter (PM), and COVID-19 cases are correlated with levels of air pollutants. However, the mechanisms of PM involvement in the spread of SARS-CoV-2 remain poorly understood. Here, we found that PM exposure increased the expression level of angiotensin-converting enzyme 2 (ACE2) and transmembrane serine protease 2 (TMPRSS2) in several epithelial cells and increased the adsorption of the SARS-CoV-2 spike protein. Instillation of PM in a hACE2 mouse model significantly increased the expression of ACE2 and Tmprss2 and viral replication in the lungs. Furthermore, PM exacerbated the pulmonary lesions caused by SARS-CoV-2 infection in the hACE2 mice. In conclusion, our study demonstrated that PM is an epidemiological factor of COVID-19, emphasizing the necessity of wearing anti-PM masks to cope with this global pandemic.

Northern pig-tailed macaques ( Macaca leonina) infected with SARS-CoV-2 show rapid viral clearance and persistent immune response.

Coronavirus disease 2019 (COVID-19), which is caused by severe acute respiratory syndrome coronavirus (SARS-CoV-2), has become an unprecedented global health emergency. At present, SARS-CoV-2-infected nonhuman primates are considered the gold standard animal model for COVID-19 research. Here, we showed that northern pig-tailed macaques ( Macaca leonina, NPMs) supported SARS-CoV-2 replication. Furthermore, compared with rhesus macaques, NPMs showed rapid viral clearance in lung tissues, nose swabs, throat swabs, and rectal swabs, which may be due to higher expression of interferon (IFN)-α in lung tissue. However, the rapid viral clearance was not associated with good outcome. In the second week post infection, NPMs developed persistent or even more severe inflammation and body injury compared with rhesus macaques. These results suggest that viral clearance may have no relationship with COVID-19 progression and SARS-CoV-2-infected NPMs could be considered as a critically ill animal model in COVID-19 research.

Interferon-armed RBD dimer enhances the immunogenicity of RBD for sterilizing immunity against SARS-CoV-2 (preprint)

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has caused a global crisis, urgently necessitating the development of safe, efficacious, convenient-to-store, and low-cost vaccine options. A major challenge is that the receptor-binding domain (RBD)-only vaccine fails to trigger long-lasting protective immunity if used solely for vaccination. To enhance antigen processing and cross-presentation in draining lymph nodes (DLNs), we developed an interferon (IFN)-armed RBD dimerized by immunoglobulin fragment (I-R-F). I-R-F efficiently directs immunity against RBD to DLN. A low dose of I-R-F induces not only high titer long-lasting neutralizing antibodies but also comprehensive T cell responses than RBD, and even provides comprehensive protection in one dose without adjuvant. This study shows that the I-R-F vaccine provides rapid and complete protection throughout upper and lower respiratory tracts against high dose SARS-CoV-2 challenge in rhesus macaques. Due to its potency and safety, this engineered vaccine may become one of the next-generation vaccine candidates in the global race to defeat COVID-19.

Progress in research in diagnosis of SARS-CoV-2 infection based on proteomics technique

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has swept the world in 2020, resulting in unprecedented pandemic of coronavirus disease 2019 (COVID-19). The number of infected persons and deaths increase every day at a frightening speed, threatening the health and life of people in the world and causing heavy burden to the global public health system. So far, nucleic acid detection is the main diagnostic method and gold standard for COVID-19. Meanwhile, other techniques and methods are also in developing for the diagnosis of SARS-CoV-2 infection. Proteomics technique is one of them. Proteomics technique has been widely used in the research of disease-related mechanism, development of diagnostic methods and pathogen identification. Up to now, there are mainly two applications of proteomics in the diagnosis of SARS-CoV-2 infection. First, proteomics based on virus particles has great potential in early diagnosis. Second, proteomics based on body fluids can be used not only for early diagnosis, but also for good monitoring the progress of infection, predicting the trend of disease, and evaluating the prognoses. In this paper, the research and application of proteomics technique in the diagnosis of SARS-CoV-2 infection in the world are summarized and prospected.

Impact of COVID-19 Pandemic on Acute Pancreatitis Presentations, Management and In-Hospital Outcomes: A Single-Center, Retrospective Observational Study from the Northeast Of China (preprint)

Introduction: Since initially detected in late December 2019, the novel coronavirus disease (COVID-19) outbreak rapidly swept the world. We aimed to evaluate the impact of COVID-19 pandemic on the pattern of hospital admissions and healthcare services for acute pancreatitis(AP). Methods: This single-center, retrospective observational study from a regional medical center in the northeast of China included all consecutively admitted patients with AP from January 23 to June 10, 2020 (during the COVID-19 outbreak in Harbin), compared with the equivalent period of the previous year, in terms of demographics, clinical characteristics, and in-hospital outcomes. Results: In the present article, we observed a reduction in AP admissions after the onset of COVID-19. With the prolonged time from symptom onset to hospitalization (32.0 [22.0–72.0] versus 18.0 [12.0–24.0] hours; P <.001), a higher proportion of patients developed acute renal failure (39% versus 34%, P =.004) and acute necrotic collection (16.5% versus 11.2%; P =.038) in the COVID-19 era. The percentage of alcohol etiology significantly reduced after the implementation of social restriction measures (11.5% versus 22.4%; P <.001), whereas biliary etiology was numerically more common amidst the COVID-19 era (41.6% versus 32.6%; P = .014). No significant differences were found in the rates of intensive care unit admission and mortality between the two groups. Conclusions: The current study preliminarily demonstrated the descending trend and delay in hospital presentations for AP during the pandemic. The COVID-19 pandemic requires the modification of medical centers to optimize the management of AP and the containment of nosocomial viral transmission. Trial Registration: ClincialTrials.gov number, ChiCTR2100043350. Funding: None to declare Declaration of Interest: None to declare Ethical Approval: Ethical approval was obtained from the Ethics Committee of 1st HMU.<br>

Analysis of s gene and protein structure difference between porcine coronavirus and SARS-CoV-2

The pandemic of COVID-19 (Corona virus disease 2019) caused by severe acute respiratory syndrome coronavirus 2(SARS-CoV-2) poses a huge threat to human health worldwide since December 2019. In order to study the correlation betweenSARS-CoV-2 and porcine coronavirus, the phylogenetic analysis of spike (S) protein amino acid sequence of human coronavirusand porcine coronavirus, the similarity analysis of the spatial structure of S1 subunit receptor binding domain (RBD) of S proteinwere conducted by bioinformatics analysis, moreover, the double- antigen sandwich ELISA kit was utilized to detect the SARSCoV-2 antibody in common porcine coronavirus positive serum. The results of phylogenetic analysis showed a low identity of Sprotein amino acid sequence between SARS-CoV-2 and porcine coronavirus, indicating a long distance of genetic evolution, andthe S1 subunit RBD spatial structure showed huge differences, meanwhile, all of the porcine coronavirus positive serum samplestested were negative of SARS-CoV-2 antibody. Our data suggested the huge differences in gene and protein level between SARS-CoV-2 and porcine coronavirus, which indicating that SARS-CoV-2 shows a minimal risk of achieving cross-species transmission byinfecting pigs to threaten public health security. This research provides a basis for studying COVID-19 pathogen traceability andbiosafety analysis of cross-species transmission.

S-Trimer, a COVID-19 subunit vaccine candidate, induces protective immunity in nonhuman primates.

SARS-CoV-2 is the underlying cause for the COVID-19 pandemic. Like most enveloped RNA viruses, SARS-CoV-2 uses a homotrimeric surface antigen to gain entry into host cells. Here we describe S-Trimer, a native-like trimeric subunit vaccine candidate for COVID-19 based on Trimer-Tag technology. Immunization of S-Trimer with either AS03 (oil-in-water emulsion) or CpG 1018 (TLR9 agonist) plus alum adjuvants induced high-level of neutralizing antibodies and Th1-biased cellular immune responses in animal models. Moreover, rhesus macaques immunized with adjuvanted S-Trimer were protected from SARS-CoV-2 challenge compared to vehicle controls, based on clinical observations and reduction of viral loads in lungs. Trimer-Tag may be an important platform technology for scalable production and rapid development of safe and effective subunit vaccines against current and future emerging RNA viruses.