Swine acute diarrhoea syndrome coronavirus (SADS-CoV) Nsp5 antagonizes type I interferon signaling by cleaving DCP1A.

Swine acute diarrhoea syndrome coronavirus (SADS-CoV), which is a recently discovered enteric coronavirus, is the major aetiological agent that causes severe clinical diarrhoea and intestinal pathological damage in pigs, and it has caused significant economic losses to the swine industry. Nonstructural protein 5, also called 3C-like protease, cleaves viral polypeptides and host immune-related molecules to facilitate viral replication and immune evasion. Here, we demonstrated that SADS-CoV nsp5 significantly inhibits the Sendai virus (SEV)-induced production of IFN-ß and inflammatory cytokines. SADS-CoV nsp5 targets and cleaves mRNA-decapping enzyme 1a (DCP1A) via its protease activity to inhibit the IRF3 and NF-κB signaling pathways in order to decrease IFN-ß and inflammatory cytokine production. We found that the histidine 41 and cystine 144 residues of SADS-CoV nsp5 are critical for its cleavage activity. Additionally, a form of DCP1A with a mutation in the glutamine 343 residue is resistant to nsp5-mediated cleavage and has a stronger ability to inhibit SADS-CoV infection than wild-type DCP1A. In conclusion, our findings reveal that SADS-CoV nsp5 is an important interferon antagonist and enhance the understanding of immune evasion by alpha coronaviruses.

An ultrasensitive electrochemical sensor for detecting porcine epidemic diarrhea virus based on a Prussian blue-reduced graphene oxide modified glassy carbon electrode.

This study developed a novel, ultrasensitive sandwich-type electrochemical immunosensor for detecting the porcine epidemic diarrhea virus (PEDV). By electrochemical co-deposition of graphene and Prussian blue, a Prussian blue-reduced graphene oxide-modified glassy carbon electrode was made, further modified with PEDV-monoclonal antibodies (mAbs) to create a new PEDV immunosensor using the double antibody sandwich technique. The electrochemical characteristics of several modified electrodes were investigated using cyclic voltammetry (CV). We optimized the pH levels and scan rate. Additionally, we examined specificity, reproducibility, repeatability, accuracy, and stability. The study indicates that the immunosensor has good performance in the concentration range of 1 × 101.88 to 1 × 105.38 TCID50/mL of PEDV, with a detection limit of 1 × 101.93 TCID50/mL at a signal-to-noise ratio of 3σ. The composite membranes produced via co-deposition of graphene and Prussian blue effectively increased electron transport to the glassy carbon electrode, boosted response signals, and increased the sensitivity, specificity, and stability of the immunosensor. The immunosensor could accurately detect PEDV, with results comparable to real-time quantitative PCR. This technique was applied to PEDV detection and served as a model for developing additional immunosensors for detecting hazardous chemicals and pathogenic microbes.

A high-frequency mobility big-data reveals how COVID-19 spread across professions, locations and age groups.

As infected and vaccinated population increases, some countries decided not to impose non-pharmaceutical intervention measures anymore and to coexist with COVID-19. However, we do not have a comprehensive understanding of its consequence, especially for China where most population has not been infected and most Omicron transmissions are silent. This paper aims to reveal the complete silent transmission dynamics of COVID-19 by agent-based simulations overlaying a big data of more than 0.7 million real individual mobility tracks without any intervention measures throughout a week in a Chinese city, with an extent of completeness and realism not attained in existing studies. Together with the empirically inferred transmission rate of COVID-19, we find surprisingly that with only 70 citizens to be infected initially, 0.33 million becomes infected silently at last. We also reveal a characteristic daily periodic pattern of the transmission dynamics, with peaks in mornings and afternoons. In addition, by inferring individual professions, visited locations and age group, we found that retailing, catering and hotel staff are more likely to get infected than other professions, and elderly and retirees are more likely to get infected at home than outside home.

Moderating Role of Peer Pressure and Positive Learning Environment Between Career Calling and Academic Procrastination in Chinese Medical Students During Controlled COVID-19 Pandemic: A Cross-Sectional Study.

Purpose: The COVID-19 pandemic sets specific circumstances that may accelerate academic procrastination behavior of medical students. Career calling is a protective factor that fights against academic procrastination and may further improve medical students' mental health and academic achievement. This study aims to determine the status of Chinese medical students' academic procrastination during controlled COVID-19 pandemic. Moreover, the study investigates the relationships and mechanisms among career calling, peer pressure, a positive learning environment, and academic procrastination. Patients and Methods: Data were collected from several Chinese medical universities through an anonymous cross-sectional survey of 3614 respondents (effective response rate = 60.0%). Using online questionnaires to collect the data and IBM SPSS Statistics 22.0 for statistical analysis. Results: The average score of academic procrastination of Chinese medical students was 2.62±0.86. This study proved the usage of peer pressure and positive learning environment as moderating roles of relationship between career calling and academic procrastination. Career calling was negatively correlated with academic procrastination (r = -0.232, p < 0.01), while it was positively correlated with peer pressure (r = 0.390, p < 0.01) and a positive learning environment (r = 0.339, p < 0.01). Moreover, academic procrastination was negatively correlated with peer pressure (r = -0.279, p < 0.01) and a positive learning environment (r = -0.242, p < 0.01). Peer pressure was positively correlated with a positive learning environment (r = 0.637, p < 0.01). Conclusion: The findings emphasize the importance of constructive peer pressure and a positive learning environment that discourages academic procrastination. Educators should highlight medical career calling education by offering related courses to fight against academic procrastination.

A loop-mediated isothermal amplification-enabled analytical assay for the detection of SARS-CoV-2: A review.

The number of words: 4645, the number of figures: 4, the number of tables: 1The outbreak of COVID-19 in December 2019 caused a global pandemic of acute respiratory disease, and with the increasing virulence of mutant strains and the number of confirmed cases, this has resulted in a tremendous threat to global public health. Therefore, an accurate diagnosis of COVID-19 is urgently needed for rapid control of SARS-CoV-2 transmission. As a new molecular biology technology, loop-mediated isothermal amplification (LAMP) has the advantages of convenient operation, speed, low cost and high sensitivity and specificity. In the past two years, rampant COVID-19 and the continuous variation in the virus strains have demanded higher requirements for the rapid detection of pathogens. Compared with conventional RT-PCR and real-time RT-PCR methods, genotyping RT-LAMP method and LAMP plus peptide nucleic acid (PNA) probe detection methods have been developed to correctly identified SARS-CoV-2 variants, which is also why LAMP technology has attracted much attention. LAMP detection technology combined with lateral flow assay, microfluidic technology and other sensing technologies can effectively enhance signals by nucleic acid amplification and help to give the resulting output in a faster, more convenient and user-friendly way. At present, LAMP plays an important role in the detection of SARS-CoV-2.

A loop-mediated isothermal amplification-enabled analytical assay for the detection of SARS-CoV-2: A review

The number of words: 4645, the number of figures: 4, the number of tables: 1The outbreak of COVID-19 in December 2019 caused a global pandemic of acute respiratory disease, and with the increasing virulence of mutant strains and the number of confirmed cases, this has resulted in a tremendous threat to global public health. Therefore, an accurate diagnosis of COVID-19 is urgently needed for rapid control of SARS-CoV-2 transmission. As a new molecular biology technology, loop-mediated isothermal amplification (LAMP) has the advantages of convenient operation, speed, low cost and high sensitivity and specificity. In the past two years, rampant COVID-19 and the continuous variation in the virus strains have demanded higher requirements for the rapid detection of pathogens. Compared with conventional RT–PCR and real-time RT–PCR methods, genotyping RT-LAMP method and LAMP plus peptide nucleic acid (PNA) probe detection methods have been developed to correctly identified SARS-CoV-2 variants, which is also why LAMP technology has attracted much attention. LAMP detection technology combined with lateral flow assay, microfluidic technology and other sensing technologies can effectively enhance signals by nucleic acid amplification and help to give the resulting output in a faster, more convenient and user-friendly way. At present, LAMP plays an important role in the detection of SARS-CoV-2.

Coach leadership in a crisis context: Investigating effective coach behaviors during the COVID-19 pandemic with a process view.

Introduction: Drawing from the crisis leadership conceptualization, this study aims to investigate coaches' opinion patterns on effective leadership behaviors during the COVID-19 pandemic. The study used a process view to explore how coaches as leaders act in pre, during, and post-crisis phases. Method: Thirty-two fulltime professional coaches (28 males and 4 females) from individual and team sports who experienced the entire COVID-19 pandemic from January 2020 to July 2021 in the United Kingdom were invited to express their perceptions of effective leadership behaviors. The study used Q methodology to analyze coaches' perceptions and experiences. Result: The study revealed that the most effective coach leadership behaviors occurred during-crisis phase, which has the most positive ratings (n = 48) compared to the pre-and post-crisis phases (n = 18). The study's main findings highlighted different phases of the COVID-19 pandemic demand various effective countermeasures from coaches. These practical and successful experiences were summarized as: division of labor, athlete-centered, team-driven, consulting, safe environment, and online coaching. Discussion: The findings of this study further highlight (1) the importance of coach leadership in creating a safe environment as it provides a much better platform to prepare for a pre-crisis stage, (2) that coaches should employ more positive than negative behaviors while interacting with team members more frequently especially during the crisis period, reducing athletes' negative feelings such as anxiety and worry, and (3) that the online training-related activities and interactions during the crisis time can be expanded to noncrisis times, as a crisis event can have positive implications for the future if handled properly.

Paxlovid accelerates cartilage degeneration and senescence through activating endoplasmic reticulum stress and interfering redox homeostasis.

BACKGROUND: The COVID-19 pandemic has become a huge threat to human health, infecting millions of people worldwide and causing enormous economic losses. Many novel small molecule drugs have been developed to treat patients with COVID-19, including Paxlovid, which block the synthesis of virus-related proteins and replication of viral RNA, respectively. Despite satisfactory clinical trial results, attention is now being paid to the long-term side effects of these antiviral drugs on the musculoskeletal system. To date, no study has reported the possible side effects, such as osteoarthritis, of Paxlovid. This study explored the effects of antiviral drug, Paxlovid, on chondrocyte proliferation and differentiation. METHODS: In this study, both in vitro and in vivo studies were performed to determine the effect of Paxlovid on chondrocyte degeneration and senescence. Furthermore, we explored the possible mechanism behind Paxlovid-induced acceleration of cartilage degeneration using transcriptome sequencing and related inhibitors were adopted to verify the downstream pathways behind such phenomenon. RESULTS: Paxlovid significantly inhibited chondrocyte extracellular matrix protein secretion. Additionally, Paxlovid significantly induced endoplasmic reticulum stress, oxidative stress, and downstream ferroptosis, thus accelerating the senescence and degeneration of chondrocytes. In vivo experiments showed that intraperitoneal injection of Paxlovid for 1 week exacerbated cartilage abrasion and accelerated the development of osteoarthritis in a mouse model. CONCLUSIONS: Paxlovid accelerated cartilage degeneration and osteoarthritis development, potentially by inducing endoplasmic reticulum stress and oxidative stress. Long-term follow-up is needed with special attention to the occurrence and development of osteoarthritis in patients treated with Paxlovid.

The study on the impact of short video tourism Vloggers at social media platform on online sharing intention.

COVID-19 has caused significant damage globally, including tourism. This study adopts the quantitative research method, selects 588 samples from tourists watching short videos to investigate the antecedents and effects of parasocial interaction between tourists and short video tourism Vloggers, and analyses them with partial least squares. Based on parasocial relationship theory, this study investigates the antecedents of parasocial relationships between tourists and short video tourism Vloggers and their willingness to share short video tourism. Results show that the consistency of values, entertainment motivation, and emotional engagement positively impact the parasocial relationships between tourists and short video tourism Vloggers and affect the online sharing intention through the parasocial relationship. The consistency of values can directly affect sharing intention. As an intermediary variable, parasocial relationship positively impacts value congruence, entertainment motivation, emotional engagement, and sharing intention. This study introduces parasocial relationship into the research of tourism short video Vloggers, which enriches the literature. Furthermore, this introduction provides new marketing strategies and suggestions for the sustainable development of tourism.

Neutralization mechanism of a human antibody with pan-coronavirus reactivity including SARS-CoV-2.

Frequent outbreaks of coronaviruses underscore the need for antivirals and vaccines that can counter a broad range of coronavirus types. We isolated a human antibody named 76E1 from a COVID-19 convalescent patient, and report that it has broad-range neutralizing activity against multiple α- and ß-coronaviruses, including the SARS-CoV-2 variants. 76E1 also binds its epitope in peptides from γ- and δ-coronaviruses. 76E1 cross-protects against SARS-CoV-2 and HCoV-OC43 infection in both prophylactic and therapeutic murine animal models. Structural and functional studies revealed that 76E1 targets a unique epitope within the spike protein that comprises the highly conserved S2' site and the fusion peptide. The epitope that 76E1 binds is partially buried in the structure of the SARS-CoV-2 spike trimer in the prefusion state, but is exposed when the spike protein binds to ACE2. This observation suggests that 76E1 binds to the epitope at an intermediate state of the spike trimer during the transition from the prefusion to the postfusion state, thereby blocking membrane fusion and viral entry. We hope that the identification of this crucial epitope, which can be recognized by 76E1, will guide epitope-based design of next-generation pan-coronavirus vaccines and antivirals.

Tolerability of Coronavirus Disease 2019 Vaccines, BNT162b2 and mRNA-1273, in Patients With Thymic Epithelial Tumors.

INTRODUCTION: Defects in immunologic self-tolerance result in an increased risk for development of paraneoplastic autoimmune diseases (ADs) and immune-mediated toxicity in response to immune stimulation in individuals with thymic epithelial tumors (TETs). We conducted a survey to evaluate the tolerability of coronavirus disease 2019 (COVID-19) mRNA vaccines in patients with TETs, including individuals with preexisting AD. METHODS: After reviewing published data on adverse events associated with the BNT162b2 (Pfizer, Inc., and BioNTech) and mRNA-1273 (ModernaTX, Inc.) mRNA vaccines, we designed and administered a questionnaire to participants at the following three time points: after each dose of vaccination and 1 month after the final dose. Questions related to AD and use of immunosuppressive drugs were included. Descriptive statistics were used to analyze data, and results were compared with previously described results related to the BNT162b2 and mRNA-1273 vaccines. RESULTS: From February 26 to June 1, 2021, we administered the survey to 54 participants (median age = 58 y, thymoma = 33, preexisting AD = 19). Common adverse events included injection site pain, fatigue, and headaches. There were no vaccination-related hospitalizations or deaths. Autoimmune flares occurred in three patients (16%) after the first dose and three patients (17%) after the second dose. Most AD flares were mild and self-limited. One patient (2%) was diagnosed with having a new AD after vaccination. CONCLUSIONS: Tolerability of COVID-19 mRNA vaccines in patients with TETs is comparable to the general population. Most patients with preexisting AD did not experience disease flares, and the development of new AD was rare. Patients with TETs should be encouraged to get vaccinated against COVID-19 owing to the documented benefits of vaccination and manageable risk profile.

A Single Vaccine Protects against SARS-CoV-2 and Influenza Virus in Mice.

The ongoing SARS-CoV-2 pandemic poses a severe global threat to public health, as do influenza viruses and other coronaviruses. Here, we present chimpanzee adenovirus 68 (AdC68)-based vaccines designed to universally target coronaviruses and influenza. Our design is centered on an immunogen generated by fusing the SARS-CoV-2 receptor-binding domain (RBD) to the conserved stalk of H7N9 hemagglutinin (HA). Remarkably, the constructed vaccine effectively induced both SARS-CoV-2-targeting antibodies and anti-influenza antibodies in mice, consequently affording protection from lethal SARS-CoV-2 and H7N9 challenges as well as effective H3N2 control. We propose our AdC68-vectored coronavirus-influenza vaccine as a universal approach toward curbing respiratory virus-causing pandemics. IMPORTANCE The COVID-19 pandemic exemplifies the severe public health threats of respiratory virus infection and influenza A viruses. The currently envisioned strategy for the prevention of respiratory virus-causing diseases requires the comprehensive administration of vaccines tailored for individual viruses. Here, we present an alternative strategy by designing chimpanzee adenovirus 68-based vaccines which target both the SARS-CoV-2 receptor-binding-domain and the conserved stalk of influenza hemagglutinin. When tested in mice, this strategy attained potent neutralizing antibodies against wild-type SARS-CoV-2 and its emerging variants, enabling an effective protection against lethal SARS-CoV-2 challenge. Notably, it also provided complete protection from lethal H7N9 challenge and efficient control of H3N2-induced morbidity. Our study opens a new avenue to universally curb respiratory virus infection by vaccination.

Tolerability of COVID-19 mRNA vaccines in patients with thymic epithelial tumors

Background Widespread adoption of vaccination against severe acute respiratory syndrome coronavirus type 2 (SARS-CoV-2), which causes COVID-19, is a crucial step towards controlling the ongoing pandemic. Messenger RNA (mRNA) vaccines currently authorized for use (BNT162b2 manufactured by Pfizer, Inc. and BioNTech, and mRNA-1273 produced by ModernaTX, Inc., MA, USA) have demonstrated safety, even in individuals with pre-existing autoimmune diseases (AD). Thymic epithelial tumors (TETs) are associated with paraneoplastic AD due to defects in immunological self-tolerance. We conducted a survey to evaluate the tolerability of COVID-19 mRNA vaccines in patients with TETs, including individuals with paraneoplastic AD. Methods After reviewing published data on adverse events (AEs) associated with the BNT162b2 and mRNA-1273 vaccines, we designed a questionnaire to assess tolerability of these vaccines in individuals with TETs. The survey consisted of 13 questions that covered vaccine-related AEs that could be self-assessed by patients. Questions related to AD and use of immunosuppressive drugs were included. The survey was administered at three timepoints: after each dose of vaccination and one month following the final dose. Descriptive statistics were used to analyze data;results were compared with those reported from phase II/III trials of the BNT162b2 and mRNA-1273 vaccines. Results From February 26th, 2021 to June 1st, 2021, 54 patients with TETs participated in the survey [median age: 58 years;females: 26 (48%);thymoma: 33 (61%), thymic carcinoma: 20 (37%);pre-existing AD: 19 (35%);concurrent immunosuppressant use: 12 (22%)]. Common AEs included injection-site pain (57% to 90%), fatigue (21% to 65%), and headaches (16% to 26%). The frequency of muscle- and joint-symptoms was not increased in patients with TETs compared with vaccine trial participants. There were no vaccination-related hospitalizations or deaths. Autoimmune flares occurred in 3 (16%) patients after the first dose and 3 (17%) patients after the second dose. One patient (2%) was diagnosed with a new AD following vaccination. Conclusions Tolerability of COVID-19 mRNA vaccines in patients with TETs is comparable to the general population. Development or flare of autoimmunity is uncommon and manageable. Patients with TETs should be encouraged to get vaccinated against COVID-19 due to documented benefits of vaccination and manageable risks.

Nonmuscle myosin heavy chain IIA facilitates SARS-CoV-2 infection in human pulmonary cells.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the causative agent of coronavirus disease 2019 (COVID-19), binds to host receptor angiotensin-converting enzyme 2 (ACE2) through its spike (S) glycoprotein, which mediates membrane fusion and viral entry. However, the expression of ACE2 is extremely low in a variety of human tissues, especially in the airways. Thus, other coreceptors and/or cofactors on the surface of host cells may contribute to SARS-CoV-2 infection. Here, we identified nonmuscle myosin heavy chain IIA (MYH9) as an important host factor for SARS-CoV-2 infection of human pulmonary cells by using APEX2 proximity-labeling techniques. Genetic ablation of MYH9 significantly reduced SARS-CoV-2 pseudovirus infection in wild type (WT) A549 and Calu-3 cells, and overexpression of MYH9 enhanced the pseudovirus infection in WT A549 and H1299 cells. MYH9 was colocalized with the SARS-CoV-2 S and directly interacted with SARS-CoV-2 S through the S2 subunit and S1-NTD (N-terminal domain) by its C-terminal domain (designated as PRA). Further experiments suggested that endosomal or myosin inhibitors effectively block the viral entry of SARS-CoV-2 into PRA-A549 cells, while transmembrane protease serine 2 (TMPRSS2) and cathepsin B and L (CatB/L) inhibitors do not, indicating that MYH9 promotes SARS-CoV-2 endocytosis and bypasses TMPRSS2 and CatB/L pathway. Finally, we demonstrated that loss of MYH9 reduces authentic SARS-CoV-2 infection in Calu-3, ACE2-A549, and ACE2-H1299 cells. Together, our results suggest that MYH9 is a candidate host factor for SARS-CoV-2, which mediates the virus entering host cells by endocytosis in an ACE2-dependent manner, and may serve as a potential target for future clinical intervention strategies.

Analysis of correlation between eye strain and eye health behavior in college students during the period of COVID-19 epidemic

Objective: To understand the relationship between eye strain and eye health behavior in college students learning at home during the period of COVID-19 epidemic, and to provide a scientific reference for improving the hygiene of using eyes among the college students.

Digital Nativity, Computer Self-Efficacy, and Technology Adoption: A Study Among University Faculties in China.

Technology acceptance and usage become obligatory for people when their work modes change as a result of an unexpected but irresistible force. This is especially true for teachers who are reluctant technology adopters compared with their students. During the COVID-19 pandemic, the Chinese government issued national policies to enforce online teaching and learning. As the success of online teaching largely depends on university faculties' readiness and intentions, how they perceive and practice technology adoption becomes an issue that warrants in-depth research. Unlike their students who grow up with technology and can be seen as digital natives, university faculties may lack competence in using technology, whether to teach or do other tasks. Previous studies on faculties' technology adoption were all conducted in situations where they made volitional decisions to use technology, but their mandatory technology use received scant attention. In addition, although studies suggested that teachers demonstrated features of digital natives, it remains unknown whether or to what extent their digital nativity correlates with technology intentions. To address these research gaps, the current study examined Chinese university faculties' intentions to use technology for online teaching by incorporating digital nativity and computer self-efficacy as key determinants into technology acceptance variables. Results suggested that digital nativity was a key factor that affected university faculties' online teaching, as evidenced by the fact that 67% of the variance could be explained by perceived usefulness, attitudes and digital nativity. In addition, it was also found that computer efficacy significantly influenced perceived ease of use.

Chinese Medicine Formula Huashibaidu Granule Early Treatment for Mild COVID-19 Patients: An Unblinded, Cluster-Randomized Clinical Trial.

Background: Previous research suggested that Chinese Medicine (CM) Formula Huashibaidu granule might shorten the disease course in coronavirus disease 2019 (COVID-19) patients. This research aimed to investigate the early treatment effect of Huashibaidu granule in well-managed patients with mild COVID-19. Methods: An unblinded cluster-randomized clinical trial was conducted at the Dongxihu FangCang hospital. Two cabins were randomly allocated to a CM or control group, with 204 mild COVID-19 participants in each cabin. All participants received conventional treatment over a 7 day period, while the ones in CM group were additionally given Huashibaidu granule 10 g twice daily. Participants were followed up to their clinical endpoint. The primary outcome was worsening symptoms before the clinical endpoint. The secondary outcomes were cure and discharge before the clinical endpoint and alleviation of composite symptoms after the 7 days of treatment. Results: All 408 participants were followed up to their clinical endpoint and included in statistical analysis. Baseline characteristics were comparable between the two groups (P > 0.05). The number of worsening patients in the CM group was 5 (2.5%), and that in the control group was 16 (7.8%) with a significant difference between groups (P = 0.014). Eight foreseeable mild adverse events occurred without statistical difference between groups (P = 0.151). Conclusion: Seven days of early treatment with Huashibaidu granule reduced the likelihood of worsening symptoms in patients with mild COVID-19. Our study supports Huashibaidu granule as an active option for early treatment of mild COVID-19 in similar well-managed medical environments. Clinical Trial Registration:www.chictr.org.cn/showproj.aspx?proj=49408, identifier: ChiCTR2000029763.

A Study on the Legislation of Territorial and Spatial Planning in Relation to Public Health Emergencies

The government's attention to and intervention in public health emergencies is one of the causes for the legislation on modern urban planning. It is now a critical period in the legislative formulation of China's territorial and spatial planning, which coincides with the unexpected onslaught of COVID-19. This study examines the relationship between public health emergencies and the legislations of territorial and spatial planning. It argues that the problems of spatial planning in response to public health emergencies primarily lie in the gaps between planning regulations and public health, emergency management, the overdue institutionalization of planning techniques, the lack of focus of planning legislations, etc. The legislation of territorial and spatial planning should be based on the governance of urban safety, health, and emergency service facilities, which aims to improve the emergency service facility system, the innovation of planning formulation technical system, and strengthen the responsiveness of planning to public health emergencies, so as to create high-quality, high-class, and resilient urban and rural spaces.

A human cell-based SARS-CoV-2 vaccine elicits potent neutralizing antibody responses and protects mice from SARS-CoV-2 challenge.

To curb the pandemic of coronavirus disease 2019 (COVID-19) caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), multiple platforms have been employed toward a safe and highly effective vaccine. Here, we develop a novel cell-based vaccine candidate, namely K562-S, by utilizing human cell K562 as a cellular carrier to display Spike (S) protein of SARS-CoV-2 on the membrane. Analogous to the traditional inactivated vaccine, K562-S cells can be propagated to a large scale by culturing and completely lose their viability after exposure to X-ray irradiation or formalin. We in turn demonstrated high immunogenicity of formalin-inactivated K562-S vaccine in both mouse and non-human primates and its protective efficacy in mice. In mice, immunization with inactivated K562-S vaccines can elicit potent neutralizing antibody (nAb) responses persisting longer than 5 months. We consequently showed in a hACE2 mouse model of SARS-CoV-2 infection that a two-shot vaccination with adjuvanted K562-S rendered greater than 3 log reduction in viral lung load and concomitant ameliorated lung pathology. Of importance, the administration of the same regimen in non-human primates was able to induce a neutralizing antibody titer averaging three-fold higher relative to human convalescent serum. These results together support the promise of K562-based, S-protein-expressing vaccines as a novel vaccination approach against SARS-CoV-2. Importantly, with a powerful capacity to carry external genes for cell-based vectors, this platform could rapidly generate two- and multiple-valent vaccines by incorporating SARS-CoV-2 mutants, SARS-CoV, or MERS-CoV.

Association between early treatment with Qingfei Paidu decoction and favorable clinical outcomes in patients with COVID-19: A retrospective multicenter cohort study.

The coronavirus disease 2019 (COVID-19) epidemic has been almost controlled in China under a series of policies, including "early diagnosis and early treatment". This study aimed to explore the association between early treatment with Qingfei Paidu decoction (QFPDD) and favorable clinical outcomes. In this retrospective multicenter study, we included 782 patients (males, 56 %; median age 46) with confirmed COVID-19 from 54 hospitals in nine provinces of China, who were divided into four groups according to the treatment initiation time from the first date of onset of symptoms to the date of starting treatment with QFPDD. The primary outcome was time to recovery; days of viral shedding, duration of hospital stay, and course of the disease were also analyzed. Compared with treatment initiated after 3 weeks, early treatment with QFPDD after less than 1 week, 1-2 weeks, or 2-3 weeks had a higher likelihood of recovery, with adjusted hazard ratio (HR) (95 % confidence interval [CI]) of 3.81 (2.65-5.48), 2.63 (1.86-3.73), and 1.92 (1.34-2.75), respectively. The median course of the disease decreased from 34 days to 24 days, 21 days, and 18 days when treatment was administered early by a week (P < 0.0001). Treatment within a week was related to a decrease by 1-4 days in the median duration of hospital stay compared with late treatment (P<0.0001). In conclusion, early treatment with QFPDD may serve as an effective strategy in controlling the epidemic, as early treatment with QFPDD was associated with favorable outcomes, including faster recovery, shorter time to viral shedding, and a shorter duration of hospital stay. However, further multicenter, prospective studies with a larger sample size should be conducted to confirm the benefits of early treatment with QFPDD.