Preparation and characterization of nanobodies targeting SARS-CoV-2 papain-like protease.

Coronavirus Papain-like protease (PLpro) mediates the cleavage of viral polyproteins and assists the virus escaping from innate immune response. Thus, PLpro is an attractive target for the development of broad-spectrum drugs as it has a conserved structure across different coronaviruses. In this study, we purified SARS-CoV-2 PLpro as an immune antigen, constructed a nanobody phage display library, and identified a set of nanobodies with high affinity for SARS-CoV-2. In addition, enzyme activity experiments demonstrated that two nanobodies had a significant inhibitory effect on the PLpro. These nanobodies should therefore be investigated as candidates for the treatment of coronaviruses.

Sensitivity-enhanced nanoplasmonic biosensor using direct immobilization of two engineered nanobodies for SARS-CoV-2 spike receptor-binding domain detection.

Sensitive, rapid, and easy-to-implement biosensors are critical in responding to highly contagious and fast-spreading severe acute respiratory syndrome coronavirus (SARS-CoV-2) mutations, enabling early infection screening for appropriate isolation and treatment measures to prevent the spread of the virus. Based on the sensing principle of localized surface plasmon resonance (LSPR) and nanobody immunological techniques, an enhanced sensitivity nanoplasmonic biosensor was developed to quantify the SARS-CoV-2 spike receptor-binding domain (RBD) in serum within 30 min. The lowest concentration in the linear range can be detected down to 0.01 ng/mL by direct immobilization of two engineered nanobodies. Both the sensor fabrication process and immune strategy are facile and inexpensive, with the potential for large-scale application. The designed nanoplasmonic biosensor achieved excellent specificity and sensitivity for SARS-CoV-2 spike RBD, providing a potential option for accurate early screening of the novel coronavirus disease 2019 (COVID-19).

Sustainable social development promotes COVID-19 pandemic control.

The rapid spread of COVID-19 had a negative impact on public health and economic recovery worldwide. There is a large and growing literature on pandemic prevention and control. However, these existing studies seldom focus on the role of sustainable social development in this process. By setting specifications of fixed-effect models based on the score data of sustainable development goals (SDG) and infection case data from 257 Chinese cities, we evaluate the positive effect of sustainable social development on pandemic control. Our results show that sustainable social development leads to a remarkable improvement in pandemic prevention and control, especially for SDG4 (Quality Education) and SDG5 (Gender Equality). Significant positive effects of sustainable social development still exist in the post-pandemic era. This study highlights the importance of promoting social SDGs by linking them with pandemic prevention and control and suggests region-specific policies based on the heterogeneous analysis results.

Structural basis of nanobodies neutralizing SARS-CoV-2 variants.

Because of the evolutionary variants of SARS-CoV-2, development of broad-spectrum neutralizing antibodies resilient to virus escape is urgently needed. We identified a group of high-affinity nanobodies from camels immunized with receptor-binding domain (RBD) of SARS-CoV-2 spike protein and resolved the structures of two non-competing nanobodies (NB1A7 and NB1B11) in complex with RBD using X-ray crystallography. The structures show that NB1A7 targets the highly conserved cryptic epitope shared by SARS-CoV-2 variants and some other coronaviruses and blocks ACE2 receptor attachment of the spike protein, and NB1B11 epitope overlaps with the contacting surface of ACE2 and is different from the binding site of NB1A7. These two nanobodies were covalently linked into multivalent and bi-paratopic formats, which significantly improved the avidity and neutralization potency and may further inhibit viral escape. The results contribute to the structure-guided design of antibodies against future variants of SARS-CoV-2 virus to combat coronavirus epidemics and pandemics.

An extended conformation of SARS-CoV-2 main protease reveals allosteric targets.

SignificanceThe coronavirus main protease (Mpro) is required for viral replication. Here, we obtained the extended conformation of the native monomer of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) Mpro by trapping it with nanobodies and found that the catalytic domain and the helix domain dissociate, revealing allosteric targets. Another monomeric state is termed compact conformation and is similar to one protomer of the dimeric form. We designed a Nanoluc Binary Techonology (NanoBiT)-based high-throughput allosteric inhibitor assay based on structural conformational change. Our results provide insight into the maturation, dimerization, and catalysis of the coronavirus Mpro and pave a way to develop an anticoronaviral drug through targeting the maturation process to inhibit the autocleavage of Mpro.

Ecological Civilization Demonstration Zone, Air Pollution Reduction, and Political Promotion Tournament in China: Empirical Evidence from a Quasi-Natural Experiment.

Using the ecological civilization demonstration zone as a quasi-natural experiment, this study has explored the effect of it on air pollution in China by employing the difference-in-differences model and the spatial difference-in-differences model, and further tested the political promotion tournament in China by employing the binary logit model. The results show that the ecological civilization demonstration zone has basically and effectively reduced air pollution, except for carbon monoxide and ozone. In addition, the spatial spillover effects of the ecological civilization demonstration zone on air pollution are not only basically supported among the treated cities, but also extremely established in the untreated cities neighboring the treated cities. Furthermore, no clear evidence supports the establishment of the political promotion tournament in China, while local cadres tend to cope with the assessment of higher officials passively rather than actively. Overall, this study sheds light on the coordination of economic development and ecological civilization from the perspective of the career concerns of local cadres.

Pre-existing Health Conditions and Epicardial Adipose Tissue Volume: Potential Risk Factors for Myocardial Injury in COVID-19 Patients.

Background: Myocardial injury is a life-threatening complication of coronavirus disease 2019 (COVID-19). Pre-existing health conditions and early morphological alterations may precipitate cardiac injury and dysfunction after contracting the virus. The current study aimed at assessing potential risk factors for COVID-19 cardiac complications in patients with pre-existing conditions and imaging predictors. Methods and Results: The multi-center, retrospective cohort study consecutively enrolled 400 patients with lab-confirmed COVID-19 in six Chinese hospitals remote to the Wuhan epicenter. Patients were diagnosed with or without the complication of myocardial injury by history and cardiac biomarker Troponin I/T (TnI/T) elevation above the 99th percentile upper reference limit. The majority of COVID-19 patients with myocardial injury exhibited pre-existing health conditions, such as hypertension, diabetes, hypercholesterolemia, and coronary disease. They had increased levels of the inflammatory cytokine interleukin-6 and more in-hospital adverse events (admission to an intensive care unit, invasive mechanical ventilation, or death). Chest CT scan on admission demonstrated that COVID-19 patients with myocardial injury had higher epicardial adipose tissue volume ([EATV] 139.1 (83.8-195.9) vs. 92.6 (76.2-134.4) cm2; P = 0.036). The optimal EATV cut-off value (137.1 cm2) served as a useful factor for assessing myocardial injury, which yielded sensitivity and specificity of 55.0% (95%CI, 32.0-76.2%) and 77.4% (95%CI, 71.6-82.3%) in adverse cardiac events, respectively. Multivariate logistic regression analysis showed that EATV over 137.1 cm2 was a strong independent predictor for myocardial injury in patients with COVID-19 [OR 3.058, (95%CI, 1.032-9.063); P = 0.044]. Conclusions: Augmented EATV on admission chest CT scan, together with the pre-existing health conditions (hypertension, diabetes, and hyperlipidemia) and inflammatory cytokine production, is associated with increased myocardial injury and mortality in COVID-19 patients. Assessment of pre-existing conditions and chest CT scan EATV on admission may provide a threshold point potentially useful for predicting cardiovascular complications of COVID-19.

The influence of pre-existing hypertension on coronavirus disease 2019 patients.

Hypertension represents one of the most common pre-existing conditions and comorbidities in Coronavirus disease 2019 (COVID-19) patients. To explore whether hypertension serves as a risk factor for disease severity, a multi-centre, retrospective study was conducted in COVID-19 patients. A total of 498 consecutively hospitalised patients with lab-confirmed COVID-19 in China were enrolled in this cohort. Using logistic regression, we assessed the association between hypertension and the likelihood of severe illness with adjustment for confounders. We observed that more than 16% of the enrolled patients exhibited pre-existing hypertension on admission. More severe COVID-19 cases occurred in individuals with hypertension than those without hypertension (21% vs. 10%, P = 0.007). Hypertension associated with the increased risk of severe illness, which was not modified by other demographic factors, such as age, sex, hospital geological location and blood pressure levels on admission. More attention and treatment should be offered to patients with underlying hypertension, who usually are older, have more comorbidities and more susceptible to cardiac complications.

Pathogenesis and management of myocardial injury in coronavirus disease 2019.

The outbreak of coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, has become a major health crisis and a worldwide pandemic. COVID-19 is characterized by high infectivity, long incubation period, diverse clinical presentations, and strong transmission intensity. COVID-19 can cause myocardial injury as well as other cardiovascular complications, particularly in senior patients with pre-existing medical conditions. The current review summarizes the epidemiological characteristics, potential mechanisms, clinical manifestations, and recent progress in the management of COVID-19 cardiovascular complications.

Pathophysiological characteristics and therapeutic approaches for pulmonary injury and cardiovascular complications of coronavirus disease 2019.

The pandemic of coronavirus disease 2019 (COVID-19) has emerged as a major health crisis, with the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) having infected over a million people around the world within a few months of its identification as a human pathogen. Initially, SARS-CoV-2 infects cells in the respiratory system and causes inflammation and cell death. Subsequently, the virus spreads out and damages other vital organs and tissues, triggering a complicated spectrum of pathophysiological changes and symptoms, including cardiovascular complications. Acting as the receptor for SARS-CoV entering mammalian cells, angiotensin converting enzyme-2 (ACE2) plays a pivotal role in the regulation of cardiovascular cell function. Diverse clinical manifestations and laboratory abnormalities occur in patients with cardiovascular injury in COVID-19, characterizing the development of this complication, as well as providing clues to diagnosis and treatment. This review provides a summary of the rapidly appearing laboratory and clinical evidence for the pathophysiology and therapeutic approaches to COVID-19 pulmonary and cardiovascular complications.