Adaptive immune responses to SARS-CoV-2 persist in the pharyngeal lymphoid tissue of children.

Most studies of adaptive immunity to SARS-CoV-2 infection focus on peripheral blood, which may not fully reflect immune responses at the site of infection. Using samples from 110 children undergoing tonsillectomy and adenoidectomy during the COVID-19 pandemic, we identified 24 samples with evidence of previous SARS-CoV-2 infection, including neutralizing antibodies in serum and SARS-CoV-2-specific germinal center and memory B cells in the tonsils and adenoids. Single-cell B cell receptor (BCR) sequencing indicated virus-specific BCRs were class-switched and somatically hypermutated, with overlapping clones in the two tissues. Expanded T cell clonotypes were found in tonsils, adenoids and blood post-COVID-19, some with CDR3 sequences identical to previously reported SARS-CoV-2-reactive T cell receptors (TCRs). Pharyngeal tissues from COVID-19-convalescent children showed persistent expansion of germinal center and antiviral lymphocyte populations associated with interferon (IFN)-γ-type responses, particularly in the adenoids, and viral RNA in both tissues. Our results provide evidence for persistent tissue-specific immunity to SARS-CoV-2 in the upper respiratory tract of children after infection.

The Relationship Between Personality Traits and Clinical Decision-Making, Anxiety and Stress Among Intern Nursing Students During COVID-19: A Cross-Sectional Study.

Purpose: The aim of this study was to investigate whether the personality traits of intern nursing students could serve as valid predictors of their psychological status and clinical decision making. Additionally, we aimed to understand the psychological state of intern nursing students during the regular epidemic prevention and control stage of COVID-19. Participants and Methods: This study was designed as a cross-sectional survey. A total of 181 intern nursing students involved in clinical placements participated in this study. Participants provided relevant data by completing the Big Five Inventory-44, the Self-Rating Anxiety Scale, the Perceived Stress Scale 14, and the Clinical Decision-Making in Nursing Scale. Results: The results showed that neuroticism (ß = -0.282, p < 0.01) and openness (ß = 0.302, p < 0.001) played significant roles in predicting clinical decision-making skills among intern nursing students. Regression analysis also showed extraversion (ß = -0.249, p < 0.01), openness (ß = 0.2, p < 0.01), and neuroticism (ß = 0.391, p < 0.001) could significantly predict stress in intern nursing students. The agreeableness (ß = -0.354, p < 0.001) and neuroticism (ß = 0.237, p < 0.01) could also predict the anxiety of intern nursing students. Additionally, some intern nursing students still suffered from anxiety and stress in the context of the ongoing pandemic. Conclusion: Personality traits are good predictors of clinical decision-making, anxiety and stress among intern nursing students. In conclusion, the openness in personality traits of intern nursing students should be valued and cultivated in clinical work, which will benefit the development of nursing talents.

Structural Basis for the Inhibition of Coronaviral Main Proteases by a Benzothiazole-Based Inhibitor.

The ongoing spread of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) has caused hundreds of millions of cases and millions of victims worldwide with serious consequences to global health and economies. Although many vaccines protecting against SARS-CoV-2 are currently available, constantly emerging new variants necessitate the development of alternative strategies for prevention and treatment of COVID-19. Inhibitors that target the main protease (Mpro) of SARS-CoV-2, an essential enzyme that promotes viral maturation, represent a key class of antivirals. Here, we showed that a peptidomimetic compound with benzothiazolyl ketone as warhead, YH-53, is an effective inhibitor of SARS-CoV-2, SARS-CoV, and MERS-CoV Mpros. Crystal structures of Mpros from SARS-CoV-2, SARS-CoV, and MERS-CoV bound to the inhibitor YH-53 revealed a unique ligand-binding site, which provides new insights into the mechanism of inhibition of viral replication. A detailed analysis of these crystal structures defined the key molecular determinants required for inhibition and illustrate the binding mode of Mpros from other coronaviruses. In consideration of the important role of Mpro in developing antivirals against coronaviruses, insights derived from this study should add to the design of pan-coronaviral Mpro inhibitors that are safer and more effective.

Examining multi-level immune response to determine prevalence of COVID-19 in pediatric tonsillectomy.

OBJECTIVE: To determine the prevalence of COVID-19 in a cohort of children undergoing tonsillectomy through assessment of B cell immune responses to SARS-CoV-2 in both peripheral blood and tonsil tissue. METHODS: In this cohort study at a tertiary pediatric hospital (Children's National Hospital) in Washington, DC, we recruited 100 children undergoing tonsillectomy from late September 2020 to January 2021. Serum, peripheral blood cells, and tonsil tissue were collected and examined for immune reactivity to SARS-CoV-2. Parent-reported clinical histories were compared to antibody and B-cell responses. RESULTS: Among 100 children undergoing tonsillectomy, 19% had evidence of immune responses to SARS-CoV-2 (CoV2+), indicating prior COVID-19. In all seropositive participants, we detected SARS-CoV-2 specific B cells in both peripheral blood mononuclear cells and tonsils, providing evidence for tissue-specific immunity in these children. Of the 19, 63% reported no known history of COVID-19, and an additional 3 were asymptomatic or unaware of an acute infection when detected on pre-surgery screen. Hispanic children represented 74% of CoV2+ subjects compared to 37% of the full cohort. 100% of CoV2+ children lived in a zip code with poverty level >10%. CONCLUSIONS: Nearly one-fifth of children undergoing tonsillectomy at an urban U.S. hospital had evidence of prior COVID-19 during the early pandemic, with the majority unaware of prior infection. Our results underscore the ethnic and socio-economic disparities of COVID-19. We found concordant evidence of humoral immune responses in children in both blood and tonsil tissue, providing evidence of local immune responses in the upper respiratory tract. LEVEL OF EVIDENCE: 3 Laryngoscope, 2022.

Network pharmacology-based predictions of active components and pharmacological mechanisms of Artemisia annua L. for the treatment of the novel Corona virus disease 2019 (COVID-19).

BACKGROUND: Novel Corona Virus Disease 2019 (COVID-19) is closely associated with cytokines storms. The Chinese medicinal herb Artemisia annua L. (A. annua) has been traditionally used to control many inflammatory diseases, such as malaria and rheumatoid arthritis. We performed network analysis and employed molecular docking and network analysis to elucidate active components or targets and the underlying mechanisms of A. annua for the treatment of COVID-19. METHODS: Active components of A. annua were identified through the TCMSP database according to their oral bioavailability (OB) and drug-likeness (DL). Moreover, target genes associated with COVID-19 were mined from GeneCards, OMIM, and TTD. A compound-target (C-T) network was constructed to predict the relationship of active components with the targets. A Compound-disease-target (C-D-T) network has been built to reveal the direct therapeutic target for COVID-19. Molecular docking, molecular dynamics simulation studies (MD), and MM-GBSA binding free energy calculations were used to the closest molecules and targets between A. annua and COVID-19. RESULTS: In our network, GO, and KEGG analysis indicated that A. annua acted in response to COVID-19 by regulating inflammatory response, proliferation, differentiation, and apoptosis. The molecular docking results manifested excellent results to verify the binding capacity between the hub components and hub targets in COVID-19. MD and MM-GBSA data showed quercetin to be the more effective candidate against the virus by target MAPK1, and kaempferol to be the other more effective candidate against the virus by target TP53. We identified A. annua's potentially active compounds and targets associated with them that act against COVID-19. CONCLUSIONS: These findings suggest that A. annua may prevent and inhibit the inflammatory processes related to COVID-19.

Add-On Effect of Honeysuckle in the Treatment of Coronavirus Disease 2019: A Systematic Review and Meta-Analysis.

Background: The outbreak of coronavirus disease 2019 (COVID-19) has rapidly spread to become a global emergency since December 2019. Chinese herbal medicine plays an important role in the treatment of COVID-19. Chinese herbal medicine honeysuckle is an extremely used traditional edible and medicinal herb. Many trials suggest that honeysuckle has obtained a good curative effect for COVID-19; however, no systematic evaluation on the clinical efficacy of honeysuckle in the treatment of COVID-19 is reported. This study aimed to evaluate the efficacy and safety of Chinese herbal medicine honeysuckle in the treatment of COVID-19. Methods: Seven electronic databases (PubMed, EMBASE, Cochrane Library, China National Knowledge Infrastructure, China Science and Technology Journal Database, Wanfang Database, and China Biology Medicine) were searched to identify randomized controlled trials (RCTs) of honeysuckle for adult patients (aged ≥ 18 years) with COVID-19. The Cochrane Risk of Bias Tool was applied to assess the methodological quality of trials. Review Manager 5.3 software was used for data analysis. Results: Overall, nine RCTs involving 1,286 patients were enrolled. Our meta-analyses found that combination therapy of honeysuckle and conventional therapy was more effective than conventional therapy alone in lung computed tomography (CT) [relative risk (RR) = 1.24, 95% confidence interval (95%CI) (1.12, 1.37), P < 0.0001], clinical cure rate [RR = 1.21, 95%CI (1.12, 1.31), P < 0.00001], and rate of conversion to severe cases [RR = 0.50, 95%CI (0.33, 0.76), P = 0.001]. Besides, combination therapy can improve the symptom score of fever, cough reduction rate, symptom score of cough, and inflammatory biomarkers (white blood cell (WBC) count; C-reactive protein (CRP)) (P < 0.05). Conclusion: Honeysuckle combined with conventional therapy may be beneficial for the treatment of COVID-19 in improving lung CT, clinical cure rate, clinical symptoms, and laboratory indicators and reducing the rate of conversion to severe cases. Besides, combination therapy did not increase adverse drug events. More high-quality RCTs are needed in the future.

Neutralization of SARS-CoV-2 pseudovirus using ACE2-engineered extracellular vesicles.

The spread of coronavirus disease 2019 (COVID-19) throughout the world has resulted in stressful healthcare burdens and global health crises. Developing an effective measure to protect people from infection is an urgent need. The blockage of interaction between angiotensin-converting enzyme 2 (ACE2) and S protein is considered an essential target for anti-severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) drugs. A full-length ACE2 protein could be a potential drug to block early entry of SARS-CoV-2 into host cells. In this study, a therapeutic strategy was developed by using extracellular vesicles (EVs) with decoy receptor ACE2 for neutralization of SARS-CoV-2. The EVs embedded with engineered ACE2 (EVs-ACE2) were prepared; the EVs-ACE2 were derived from an engineered cell line with stable ACE2 expression. The potential effect of the EVs-ACE2 on anti-SARS-CoV-2 was demonstrated by both in vitro and in vivo neutralization experiments using the pseudovirus with the S protein (S-pseudovirus). EVs-ACE2 can inhibit the infection of S-pseudovirus in various cells, and importantly, the mice treated with intranasal administration of EVs-ACE2 can suppress the entry of S-pseudovirus into the mucosal epithelium. Therefore, the intranasal EVs-ACE2 could be a preventive medicine to protect from SARS-CoV-2 infection. This EVs-based strategy offers a potential route to COVID-19 drug development.

Safety and immunogenicity of an inactivated SARS-CoV-2 vaccine in healthy adults aged 18 years or older: A randomized, double-blind, placebo-controlled, phase 1/2 trial.

BACKGROUND: We aimed to assess the safety and immunogenicity of an inactivated vaccine against COVID-19 in Chinese adults aged ≥18 years. METHODS: This is an ongoing randomized, double-blind, placebo-controlled, phase 1/2 clinical trial among healthy adults aged ≥18 years in Henan Province, China. Participants (n = 336 in 18-59 age group and n = 336 in ≥60 age group) were enrolled between April 12 and May 17 2020, and were equally randomized to receive vaccine or placebo (aluminum hydroxide adjuvant) in a three-dose schedule of 2·5, 5, or 10 µg on days 0, 28, and 56. Another 448 adults aged 18-59 years were equally allocated to four groups (a one-dose schedule of 10 µg, and two-dose schedules of 5 µg on days 0 and 14/21/28) and received vaccine or placebo (ratio 3:1 within each group). The primary outcomes were 7-day post-injection adverse reactions and neutralizing antibody titres on days 28 and 90 after the whole-course vaccination. Trial registration: www.chictr.org.cn #ChiCTR2000031809. FINDINGS: The 7-day adverse reactions occurred in 4·8% to 32·1% of the participants in various groups, and most adverse reactions were mild, transient, and self-limiting. Twenty participants reported 68 serious adverse events which were judged to be unrelated to the vaccine. The 90-day post-injection geometric mean titres of neutralizing antibody ranged between 87 (95% CI: 61-125) and 129 (99-169) for three-dose schedule among younger and older adults; 20 (14-27), 53 (38-75), and 44 (32-61) in 5 µg days 0 and 14/21/28 groups, respectively, and 7 (6-9) in one-dose 10 µg group. There were no detectable antibody responses in all placebo groups. INTERPRETATION: The inactivated vaccine against COVID-19 was well tolerated and immunogenic in both younger and older adults. The two-dose schedule of 5 µg on days 0 and 21/28 and three-dose schedules on days 0, 28, and 56 could be further evaluated for long-term safety and efficacy in the phase 3 trials.

Staff's Psychological Well-Being and Coping Mechanisms During COVID-19 Lockdown in Care Homes for Older Adults: A Structural Equation Modeling Analysis.

The current study investigated the psychological well-being and coping mechanisms of care home staff during the coronavirus disease 2019 (COVID-19) lockdown. Among 147 staff members, 21.8%, 24.5%, and 12.9% reported depression, anxiety, and stress, respectively. The results of structural equation modeling showed that self-efficacy and coping strategies had direct effects on psychological well-being. In the paths from self-perceived caregiving to psychological well-being, self-efficacy and positive coping strategies played mediating roles independently and together, and social support played a mediating role together with coping strategies. Care home staff's psychological well-being was undermined during the COVID-19 lockdown. Interventions aimed at improving staff's self-efficacy, adoption of positive coping strategies, and avoidance of negative coping strategies or considerations of social support along with coping strategies are suggested to decrease exhibited symptoms of depression, anxiety, and stress. [Research in Gerontological Nursing, 14(4), 180-190.].

Efficacy and safety of Xiyanping injection in the treatment of COVID-19: A multicenter, prospective, open-label and randomized controlled trial.

Xiyanping (XYP) is a Chinese herbal medicine used in the clinic to treat respiratory infection and pneumonia. Recent evidence identified XYP as a potential inhibitor of severe acute respiratory syndrome coronavirus 2, implying XYP as a possible treatment for the coronavirus disease 2019 (COVID-19). Here, we conducted a prospective, multicenter, open-label and randomized controlled trial to evaluate the safety and effectiveness of XYP injection in patients with mild to moderate COVID-19. We consecutively recruited 130 COVID-19 patients with mild to moderate symptoms from five study sites, and randomized them in 1:1 ratio to receive XYP injection in combination with standard therapy or receive standard supportive therapy alone. We found that XYP injection significantly reduced the time to cough relief, fever resolution and virus clearance. Less patients receiving XYP injection experienced disease progression to the severe stage during the treatment process. No severe adverse events were reported during the study. Taken together, XYP injection is safe and effective in improving the recovery of patients with mild to moderate COVID-19. However, further studies are warranted to evaluate the efficacy of XYP in an expanded cohort comprising COVID-19 patients at different disease stages.

Safety and efficacy of artemisinin-piperaquine for treatment of COVID-19: an open-label, non-randomised and controlled trial.

BACKGROUND: There are no effective therapies for patients with coronavirus disease-2019 (COVID-19). METHODS: Forty-one patients with confirmed COVID-19 were enrolled in the study and divided into two groups: artemisinin-piperaquine (AP) (n = 23) and control (n = 18). The primary outcome were the time taken to reach undetectable levels of severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2) and the percentage of participants with undetectable SARS-CoV-2 on days 7, 10, 14, and 28. The computed tomography (CT) imaging changes within 10 days, corrected QT interval changes, adverse events, and abnormal laboratory parameters were the secondary outcomes. RESULTS: The mean time to reach undetectable viral RNA (mean ± standard deviation) was 10.6 ± 1.1 days (95% confidence interval [CI] 8.4-12.8) for the AP group and 19.3 ± 2.1 days (95% CI 15.1-23.5) for the control group. The percentages of patients with undetectable viral RNA on days 7, 10, 14, 21, and 28 were 26.1%, 43.5%, 78.3%, 100%, and 100%, respectively, in the AP group and 5.6%, 16.7%, 44.4%, 55.6%, and 72.2%, respectively, in the control group. The CT imaging within 10 days post-treatment showed no significant between-group differences (P > 0.05). Both groups had mild adverse events. CONCLUSIONS: In patients with mild-to-moderate COVID-19, the time to reach undetectable SARS-CoV-2 was significantly shorter in the AP group than that in the control group. However, physicians should consider QT interval changes before using AP.

[Preventing Infection Measures of COVID-19 Patients during Mechanical Ventilation].

OBJECTIVE: To explore the preventing infection measures of new coronavirus disease 2019(COVID-19) patients during mechanical ventilation, and to provide reference for the safe application of mechanical ventilation. METHODS: Retrieved from PubMed, Ovid and other databases, and combined with the application experience of mechanical ventilation were collected to explore the preventing infection measures of COVID-19 patients during mechanical ventilation. RESULTS: This paper put forward the preventing infection measures of external circuit, internal circuit, outer surface, filter and special parts in ventilator. The preventing infection measures of sputum suction and nebulization were summarized. CONCLUSIONS: The preventing infection measures of COVID-19 patients during mechanical ventilation are successfully completed, which can provide suggestions for the application and maintenance of mechanical ventilation.

Clinical and molecular characteristics of COVID-19 patients with persistent SARS-CoV-2 infection (preprint)

The clinical features, molecular characteristics, and immune responses of COVID-19 patients with persistent SARS-CoV-2 infection are not yet well described. In this study, we investigated the differences in clinical parameters, laboratory indexes, plasma cytokines, and peripheral blood mononuclear cell responses, which were assessed using single-cell RNA-sequencing in patients with non-critical COVID-19 with long durations (LDs) and short durations (SDs) of viral shedding. Our results revealed that clinical parameters and laboratory indexes, such as c-reactive protein (CRP) and D-dimer, were comparable between SDs and LDs. Most inflammatory cytokines/chemokines, such as IL-2, IL2R, TNFα/β, IL1β, and CCL5 were present at low levels in LDs. Our single-cell RNA-sequencing revealed a reconfiguration of the peripheral immune cell phenotype in LDs, including decreases in natural killer (NK) cells and CD14+ monocytes and an increase in regulatory T cells (Tregs). Furthermore, most cell subsets in LDs consistently exhibited reduced expression of ribosomal protein (RP) genes, indicating dysfunctions in cytokine/chemokine synthesis, folding, modification, and assembly. Accordingly, the negative correlation between the RP levels and viral shedding duration was validated in an independent cohort of bulk-RNA-sequencing data from 103 non-critical patients, which may help guide clinical management and resource allocation. Moreover, peripheral T and NK cells and memory B cells in LDs likely failed to activate, which contributed to the persistence of viral shedding.

Follow-up study of the pulmonary function and related physiological characteristics of COVID-19 survivors three months after recovery.

BACKGROUND: The long-term pulmonary function and related physiological characteristics of COVID-19 survivors have not been studied in depth, thus many aspects are not understood. METHODS: COVID-19 survivors were recruited for high resolution computed tomography (HRCT) of the thorax, lung function and serum levels of SARS-CoV-2 IgG antibody tests 3 months after discharge. The relationship between the clinical characteristics and the pulmonary function or CT scores were investigated. FINDINGS: Fifty-five recovered patients participated in this study. SARS-CoV-2 infection related symptoms were detected in 35 of them and different degrees of radiological abnormalities were detected in 39 patients. Urea nitrogen concentration at admission was associated with the presence of CT abnormalities (P = 0.046, OR 7.149, 95% CI 1.038 to 49.216). Lung function abnormalities were detected in 14 patients and the measurement of D-dimer levels at admission may be useful for prediction of impaired diffusion defect (P = 0.031, OR 1.066, 95% CI 1.006 to 1.129). Of all the subjects, 47 of 55 patients tested positive for SARS-CoV-2 IgG in serum, among which the generation of Immunoglobulin G (IgG) antibody in female patients was stronger than male patients in infection rehabilitation phase. INTERPRETATION: Radiological and physiological abnormalities were still found in a considerable proportion of COVID-19 survivors without critical cases 3 months after discharge. Higher level of D-dimer on admission could effectively predict impaired DLCO after 3 months discharge. It is necessary to follow up the COVID-19 patients to appropriately manage any persistent or emerging long-term sequelae. FUNDING: Key Scientific Research Projects of Henan Higher Education Institutions.