Prolonged airway explant culture enables study of health, disease, and viral pathogenesis (preprint)

In vitro models play a major role in studying airway physiology and disease. However, the native lungs complex tissue architecture and non-epithelial cell lineages are not preserved in these models. Ex vivo tissue models could overcome in vitro limitations, but methods for long-term maintenance of ex vivo tissue has not been established. We describe methods to culture human large airway explants, small airway explants, and precision-cut lung slices for at least 14 days. Human airway explants recapitulate genotype-specific electrophysiology, characteristic epithelial, endothelial, stromal and immune cell populations, and model viral infection after 14 days in culture. These methods also maintain mouse, rabbit, and pig tracheal explants. Notably, intact airway tissue can be cryopreserved, thawed, and used to generate explants with recovery of function 14 days post-thaw. These studies highlight the broad applications of airway tissue explants and their use as translational intermediates between in vitro and in vivo studies.

Chronic airway epithelial hypoxia exacerbates injury in muco-obstructive lung disease through mucus hyperconcentration.

Unlike solid organs, human airway epithelia derive their oxygen from inspired air rather than the vasculature. Many pulmonary diseases are associated with intraluminal airway obstruction caused by aspirated foreign bodies, virus infection, tumors, or mucus plugs intrinsic to airway disease, including cystic fibrosis (CF). Consistent with requirements for luminal O2, airway epithelia surrounding mucus plugs in chronic obstructive pulmonary disease (COPD) lungs are hypoxic. Despite these observations, the effects of chronic hypoxia (CH) on airway epithelial host defense functions relevant to pulmonary disease have not been investigated. Molecular characterization of resected human lungs from individuals with a spectrum of muco-obstructive lung diseases (MOLDs) or COVID-19 identified molecular features of chronic hypoxia, including increased EGLN3 expression, in epithelia lining mucus-obstructed airways. In vitro experiments using cultured chronically hypoxic airway epithelia revealed conversion to a glycolytic metabolic state with maintenance of cellular architecture. Chronically hypoxic airway epithelia unexpectedly exhibited increased MUC5B mucin production and increased transepithelial Na+ and fluid absorption mediated by HIF1α/HIF2α-dependent up-regulation of ß and γENaC (epithelial Na+ channel) subunit expression. The combination of increased Na+ absorption and MUC5B production generated hyperconcentrated mucus predicted to perpetuate obstruction. Single-cell and bulk RNA sequencing analyses of chronically hypoxic cultured airway epithelia revealed transcriptional changes involved in airway wall remodeling, destruction, and angiogenesis. These results were confirmed by RNA-in situ hybridization studies of lungs from individuals with MOLD. Our data suggest that chronic airway epithelial hypoxia may be central to the pathogenesis of persistent mucus accumulation in MOLDs and associated airway wall damage.

Early Serial Echocardiographic and Ultrasonographic Findings in Critically Ill Patients With COVID-19

Background Cardiac function of critically ill patients with COVID-19 generally has been reported from clinically obtained data. Echocardiographic deformation imaging can identify ventricular dysfunction missed by traditional echocardiographic assessment. Research Question What is the prevalence of ventricular dysfunction and what are its implications for the natural history of critical COVID-19? Study Design and Methods This is a multicenter prospective cohort of critically ill patients with COVID-19. We performed serial echocardiography and lower extremity vascular ultrasound on hospitalization days 1, 3, and 8. We defined left ventricular (LV) dysfunction as the absolute value of longitudinal strain of < 17% or LV ejection fraction (LVEF) of < 50%. Primary clinical outcome was inpatient survival. Results We enrolled 110 patients. Thirty-nine (35.5%) died before hospital discharge. LV dysfunction was present at admission in 38 patients (34.5%) and in 21 patients (36.2%) on day 8 (P = .59). Median baseline LVEF was 62% (interquartile range [IQR], 52%-69%), whereas median absolute value of baseline LV strain was 16% (IQR, 14%-19%). Survivors and nonsurvivors did not differ statistically significantly with respect to day 1 LV strain (17.9% vs 14.4%;P = .12) or day 1 LVEF (60.5% vs 65%;P = .06). Nonsurvivors showed worse day 1 right ventricle (RV) strain than survivors (16.3% vs 21.2%;P = .04). Interpretation Among patients with critical COVID-19, LV and RV dysfunction is common, frequently identified only through deformation imaging, and early (day 1) RV dysfunction may be associated with clinical outcome.

Neighboring in the time of Coronavirus? Paying civil attention while walking the neighborhood

Whereas physical distancing slows the spread of COVID-19, tactics associated with it have the potential to exacerbate social isolation in our societies. Far from withdrawing from one another during this period, however, engagement in sanctioned localized leisure, particularly neighborhood walking, has facilitated a welcome resurgence in neighboring, an active engagement in authentic social interactions with neighbors, albeit from a safe distance. What existed as a social contract of civil inattention in public space appears to have shifted with the pandemic to greater civil attention. With this in mind, this critical commentary aims to explore how, in this time of crisis, neighborhood walking appears to have facilitated a rediscovery of our social connectedness as neighbors. While there is no guarantee the resurgence of neighboring will survive the pandemic, it warrants recognition that, at least early on in this crisis, leisure affordances play a role in strengthening social connections among familiar strangers. (PsycInfo Database Record (c) 2023 APA, all rights reserved)

Teacher learning through collaborative curriculum design in the midst of a pandemic: A cultural historical activity theory investigation

Collaborative design, or co-design, is an effective form of professional development that promotes teacher learning. In this study, we used cultural-historical activity theory (CHAT) to investigate how teachers attempt to resolve systematic contradictions as they co-designed and enacted a four-week science unit on COVID-19. Our findings indicated that the teachers faced significant challenges in implementing the COVID-19 unit. We also found that tensions among teachers and positioning teachers as the ultimate decision-makers were particularly useful for promoting teacher learning in the midst of a pandemic. [ FROM AUTHOR]

Spiking SARS-CoV-2 antiviral immunity in the respiratory tract.

The COVID-19 pandemic enabled the successful launch of mRNA-based vaccines that, when given intramuscularly, elicit spike-specific antibodies and prevent severe disease, but do not promote mucosal immunity. New data suggest how to boost systemic immunity and elicit pulmonary immunity in a way that more effectively controls infection and impairs transmission.

Prenatal alcohol prevention in the UK: mapping the landscape through systematic collaborative review

BACKGROUND: UK policy makers have called for urgent action to reduce prenatal alcohol exposure (PAE), but evidence on what is effective is scarce. We aimed to identify, evaluate, and synthesise evidence on content, process aspects, and effectiveness of UK PAE prevention initiatives. METHODS: We conducted a systematic search of published and grey literature on UK PAE prevention (PROSPERO: CRD42020209460);consultations with 61 academic, practice, policy, third sector, and public stakeholders;and semi-structured 12 interviews with pregnant people (who were aged ≥18 years and ≥12 weeks' gestation) and service providers to discuss experiences of PAE prevention. Participants were purposively sampled to cover each UK region and identified through maternity sites, social media and, for stakeholder consultees, researcher networks. Information from relevant PAE prevention initiatives from the literature was independently extracted by two reviewers. Ethical approval and informed consent were obtained for interviews, which were recorded and transcribed. Qualitative evidence was synthesised using thematic analysis. Quantitative data will be summarised using descriptive statistics and meta-analysis. FINDINGS: We identified 14 PAE prevention initiatives through literature searches (22 of 4064 results were eligible), stakeholder consultation, and interviews. Initiatives included screening and intervention, campaigns, and education or training. Seven initiatives were identified in the north of England. Two initiatives were identified in Scotland and two in Wales. The East of England, West Midlands, and South East of England had one each. None were identified in Southwest of England or Northern Ireland. Barriers to prevention included absence of resources, excessive workload, concerns around blame, and COVID-19. Enablers included workforce training and trust between pregnant people and service providers. Effectiveness of evidence was scarce. INTERPRETATION: Key strengths include extensive searches and multidisciplinary consultation. Data collection and analyses are ongoing and will be finalised before November, 2022. This research will provide a comprehensive analysis of current provision, providing crucial evidence to inform research and practice. FUNDING: The National Institute for Health and Care Research.

Teacher learning through collaborative curriculum design in the midst of a pandemic: A cultural historical activity theory investigation

Collaborative design, or co-design, is an effective form of professional development that promotes teacher learning. In this study, we used cultural-historical activity theory (CHAT) to investigate how teachers attempt to resolve systematic contradictions as they co-designed and enacted a four-week science unit on COVID-19. Our findings indicated that the teachers faced significant challenges in implementing the COVID-19 unit. We also found that tensions among teachers and positioning teachers as the ultimate decision-makers were particularly useful for promoting teacher learning in the midst of a pandemic.

A single intranasal administration of AdCOVID protects against SARS-CoV-2 infection in the upper and lower respiratory tracts.

The coronavirus disease 2019 (COVID-19) pandemic has illustrated the critical need for effective prophylactic vaccination to prevent the spread of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Intranasal vaccination is an attractive approach for preventing COVID-19 as the nasal mucosa is the site of initial SARS-CoV-2 entry and viral replication prior to aspiration into the lungs. We previously demonstrated that a single intranasal administration of a candidate adenovirus type 5-vectored vaccine encoding the receptor-binding domain of the SARS-CoV-2 spike protein (AdCOVID) induced robust immunity in both the airway mucosa and periphery, and completely protected K18-hACE2 mice from lethal SARS-CoV-2 challenge. Here we show that a single intranasal administration of AdCOVID limits viral replication in the nasal cavity of K18-hACE2 mice. AdCOVID also induces sterilizing immunity in the lungs of mice as reflected by the absence of infectious virus. Finally, AdCOVID prevents SARS-CoV-2 induced pathological damage in the lungs of mice. These data show that AdCOVID not only limits viral replication in the respiratory tract, but it also prevents virus-induced inflammation and immunopathology following SARS-CoV-2 infection.

Student interest, concerns, and information-seeking behaviors related to COVID-19

COVID-19 creates an opportunity for science classrooms to relate content about viruses to students’ personal experiences with the pandemic. Previous researchers have shown that students are interested in crisis situations like disease outbreaks;however, they primarily acquire information about these events through internet sources which are often biased. We argue that it is important to understand student interest, concerns, and information-seeking behaviors related to COVID-19 to support science classroom learning and engagement about the virus and other potential outbreaks. We surveyed 224 high school students and analyzed their responses to six open-ended questions. We found that students expressed the most interest in topics related to the origin of COVID-19 and vaccines. Their greatest concerns included contracting the virus or someone they know contracting the virus and vaccine distribution. Of our sample, only 6.7% reported using their teachers as their source of COVID-19 information. Science classrooms have the potential to pique students’ situational interest by discussing COVID-19 topics that are important to students, which can increase their academic performance, content knowledge, attention, and engagement in learning about viruses. Moreover, classroom instruction about COVID-19 by teachers has shown to alleviate students’ stress and anxiety. We provide key areas of student interest about COVID-19 to help educators address students’ questions and improve curricular resources on viral pandemics.

Role of iBALT in Respiratory Immunity.

Pulmonary respiration inevitably exposes the mucosal surface of the lung to potentially noxious stimuli, including pathogens, allergens, and particulates, each of which can trigger pulmonary damage and inflammation. As inflammation resolves, B and T lymphocytes often aggregate around large bronchi to form inducible Bronchus-Associated Lymphoid Tissue (iBALT). iBALT formation can be initiated by a diverse array of molecular pathways that converge on the activation and differentiation of chemokine-expressing stromal cells that serve as the scaffolding for iBALT and facilitate the recruitment, retention, and organization of leukocytes. Like conventional lymphoid organs, iBALT recruits naïve lymphocytes from the blood, exposes them to local antigens, in this case from the airways, and supports their activation and differentiation into effector cells. The activity of iBALT is demonstrably beneficial for the clearance of respiratory pathogens; however, it is less clear whether it dampens or exacerbates inflammatory responses to non-infectious agents. Here, we review the evidence regarding the role of iBALT in pulmonary immunity and propose that the final outcome depends on the context of the disease.

Single-Dose Intranasal Administration of AdCOVID Elicits Systemic and Mucosal Immunity against SARS-CoV-2 and Fully Protects Mice from Lethal Challenge.

The coronavirus disease 2019 (COVID-19) pandemic has highlighted the urgent need for effective prophylactic vaccination to prevent the spread of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Intranasal vaccination is an attractive strategy to prevent COVID-19 as the nasal mucosa represents the first-line barrier to SARS-CoV-2 entry. The current intramuscular vaccines elicit systemic immunity but not necessarily high-level mucosal immunity. Here, we tested a single intranasal dose of our candidate adenovirus type 5-vectored vaccine encoding the receptor-binding domain (RBD) of the SARS-CoV-2 spike protein (AdCOVID) in inbred, outbred, and transgenic mice. A single intranasal vaccination with AdCOVID elicited a strong and focused immune response against RBD through the induction of mucosal IgA in the respiratory tract, serum neutralizing antibodies, and CD4+ and CD8+ T cells with a Th1-like cytokine expression profile. A single AdCOVID dose resulted in immunity that was sustained for over six months. Moreover, a single intranasal dose completely protected K18-hACE2 mice from lethal SARS-CoV-2 challenge, preventing weight loss and mortality. These data show that AdCOVID promotes concomitant systemic and mucosal immunity and represents a promising vaccine candidate.

Developing and Using Multiple Models to Promote Scientific Literacy in the Context of Socio-Scientific Issues.

Learning science in the context of socio-scientific issues (SSI) can promote scientific literacy that links science to everyday life and society. In this position paper, we argue that developing and using multiple models equip students with the appropriate knowledge and skills needed to deal with complex issues. We draw upon literature from science education and philosophy of science and advance our theoretical argument about why it is critical for students to develop and use multiple models as part of their science learning experiences in general, and how the practice benefits students in the context of SSI in particular. We posit that students should engage in both scientific and socio-scientific models as they explore a complex societal issue because (1) engagement in multiple scientific models promotes students' understanding about the phenomena relevant to the focal issue, and (2) engagement in socio-scientific models helps students to use that scientific knowledge in the larger social contexts and reason about how interacting science and social factors may impact students' positions on the complex issue. We take COVID-19 as the learning context and present exemplar models students can develop and use as they learn about the pandemic. We conclude the paper by discussing the teaching aspects of the proposed modeling approach for SSI-based instruction as well as identifying possible areas for future research.

Perceived ability to comply with national COVID-19 mitigation strategies and their impact on household finances, food security, and mental well-being of medical and pharmacy students in Liberia.

INTRODUCTION: From the outset of the COVID-19 pandemic, guidance from WHO has promoted social distancing, wearing face masks, frequent hand washing, and staying-at-home as measures to prevent the spread of COVID-19. For many across Africa, compliance can be difficult. The aim of this study was to 1) understand the impact of student's household's ability to comply with COVID-19 mitigation strategies, 2) identify predictors of mitigation strategy compliance, and 3) describe the impact of COVID-19 on household economics, food-security, and mental well-being. MATERIALS AND METHODS: We conducted an email-based survey among current medical and pharmacy students of the University of Liberia College of Health Sciences between July and October 2020. The questionnaire was designed to explore their household's ability to comply with current mitigation strategies, as well as the pandemic´s impact on the student's household's finances and food security. Descriptive statistics were used to delineate demographic characteristics. Logistic regression was used to model factors associated with ability to comply with COVID-19 mitigation strategies, as well as participant's food security. RESULTS: 113 persons responded to the questionnaire. Seventy-six (67∙3%) reported income losses as a result of the pandemic, with 93 (82∙3%) reporting being "somewhat" or "very worried" about their households' finances. Seventy-seven (68∙1%) participants reported food stocks that were sufficient for one-week or less. Forty (35%) participants reported eating less preferred foods or skipping meals in the past week. Overall, 20 participants (19∙4%) had a positive depression screen. CONCLUSIONS: Study participants showed mixed results in being able to adhere to national COVID-19 mitigation strategies, with household level stressors experienced around finances and food security. Until Liberia has access to vaccinations for most of its citizens, COVID-19 response measures need to provide social protections that address basic needs (shelter, clothing and food), and which specifically targets food insecurity. Preventative interventions for mental health problems must be incorporated into Liberia's response to the pandemic.

Single-dose intranasal administration of AdCOVID elicits systemic and mucosal immunity against SARS-CoV-2 in mice (preprint)

The coronavirus disease 2019 (COVID-19) pandemic has highlighted the urgent need for effective preventive vaccination to reduce burden and spread of severe acute respiratory syndrome (SARS) coronavirus 2 (SARS-CoV-2) in humans. Intranasal vaccination is an attractive strategy to prevent COVID-19 as the nasal mucosa represents the first-line barrier to SARS-CoV-2 entry before viral spread to the lung. Although SARS-CoV-2 vaccine development is rapidly progressing, the current intramuscular vaccines are designed to elicit systemic immunity without conferring mucosal immunity. Here, we show that AdCOVID, an intranasal adenovirus type 5 (Ad5)-vectored vaccine encoding the receptor binding domain (RBD) of the SARS-CoV-2 spike protein, elicits a strong and focused immune response against RBD through the induction of mucosal IgA, serum neutralizing antibodies and CD4+ and CD8+ T cells with a Th1-like cytokine expression profile. Therefore, AdCOVID, which promotes concomitant systemic and local mucosal immunity, represents a promising COVID-19 vaccine candidate.

The landscape of antibody binding to SARS-CoV-2 (preprint)

The search for potential antibody-based diagnostics, vaccines, and therapeutics for pandemic severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has focused almost exclusively on the spike (S) and nucleocapsid (N) proteins. Coronavirus membrane (M), orf3a, and orf8 proteins are also humoral immunogens in other coronaviruses (CoVs) but remain largely uninvestigated for SARS-CoV-2. Here we show that SARS-CoV-2 infection induces robust antibody responses to epitopes throughout the SARS-CoV-2 proteome, particularly in M, in which one epitope achieved near-perfect diagnostic accuracy. We map 79 B cell epitopes throughout the SARS-CoV-2 proteome and demonstrate that anti-SARS-CoV-2 antibodies appear to bind homologous peptide sequences in the 6 known human CoVs. Our results demonstrate previously unknown, highly reactive B cell epitopes throughout the full proteome of SARS-CoV-2 and other CoV proteins, especially M, which should be considered in diagnostic, vaccine, and therapeutic development.

The human brain vasculature shows a distinct expression pattern of SARS-CoV-2 entry factors (preprint)

A large number of hospitalized COVID-19 patients show neurological symptoms such as ischemic- and hemorrhagic stroke as well as encephalitis, and SARS-CoV-2 can directly infect endothelial cells leading to endotheliitis across multiple vascular beds. These findings suggest an involvement of the brain- and peripheral vasculature in COVID-19, but the underlying molecular mechanisms remain obscure. To understand the potential mechanisms underlying SARS-CoV-2 tropism for brain vasculature, we constructed a molecular atlas of the expression patterns of SARS-CoV-2 viral entry-associated genes (receptors and proteases) and SARS-CoV-2 interaction partners in human (and mouse) adult and fetal brain as well as in multiple non-CNS tissues in single-cell RNA-sequencing data across various datasets. We observed a distinct expression pattern of the cathepsins B (CTSB) and -L (CTSL) - which are able to substitute for the ACE2 co-receptor TMPRSS2 - in the human vasculature with CTSB being mainly expressed in the brain vasculature and CTSL predominantly in the peripheral vasculature, and these observations were confirmed at the protein level in the Human Protein Atlas and using immunofluorescence stainings. This expression pattern of SARS-CoV-2 viralentry associated proteases and SARS-CoV-2 interaction partners was also present in endothelial cells and microglia in the fetal brain, suggesting a developmentally establishedSARS-CoV-2 entry machinery in the human vasculature. At both the adult and fetal stages, we detected a distinct pattern of SARS-CoV-2 entry associated genes' transcripts in brain vascular endothelial cells and microglia, providing a potential explanation for an inflammatory response in the brain endothelium upon SARS-CoV-2 infection. Moreover, CTSB was co-expressed in adult and fetal brain endothelial cells with genes and pathways involved in innate immunity and inflammation, angiogenesis, blood-brain-barrier permeability, vascular metabolism, and coagulation, providing a potential explanation for the role of brain endothelial cells in clinically observed (neuro)vascular symptoms in COVID-19 patients. Our study serves as a publicly available single-cell atlas of SARS-CoV-2 related entry factors and interaction partners in human and mouse brain endothelial- and perivascular cells, which can be employed for future studies in clinical samples of COVID-19 patients.