Genetic overlap study between idiopathic pulmonary fibrosis and COVID-19

Background/Objectives: Genetic factors influence COVID-19 susceptibility and outcomes, including the development of pulmonary fibrosis (i.e. lung scarring). Idiopathic pulmonary fibrosis (IPF) is a progressive lung disease and the most common cause of pulmonary fibrosis in the general population. Genome-wide association studies (GWAS) of COVID-19 and IPF revealed genes associated with both diseases, suggesting these share genetic risk factors. Here we performed a genetic overlap study between COVID-19 and IPF. Method(s): Summary statistics from an IPF 5-way meta-GWAS and from the COVID-19 Host Genetics initiative GWAS metaanalysis (v6) were used. We performed genetic correlation analyses and assessed individual genetic signals to identify those variants shared between both traits. We conducted colocalisation analyses to determine whether the same causal variant was driving both traits. Finally, the association of overlapping variants with gene expression was assessed and a phenome-wide association study was performed. Result(s): There was a positive genetic correlation between severe COVID-19 and IPF. We found four genetic loci with likely shared causal variants between both traits, including one novel risk locus at 7q22.1 that colocalised with decreased ZKSCAN1 and TRIM4 expression in blood. The other three loci colocalised with MUC5B, ATP11A and DPP9 expression. The locus associated with increased ATP11A expression was also associated with higher Hb1AC levels, a biomarker used in diabetes. Conclusion(s): Results suggest there are shared biological processes driving IPF and severe COVID-19 phenotypes.

Chilblain lupus erythematosus associated with systemic lupus erythematosus: A classic diagnosis in a current epidemiological context

Objectives: Chilblain lupus erythematosus (LE) is a rare chronic cutaneous lupus erythematosus (CCLE) characterized by the appearance of violaceous plaques in acral regions most exposed to cold. The isolated form affects middle-aged women, while the familial form manifests in early childhood and is associated with mutations in the TREX1 gene. Result(s): A 13-year-old adolescent, with no relevant family history, was referred in March 2021 for suspected chilblain-like lesions associated with COVID-19 infection. The patient presented with multiple violaceous papules on hands and feet. The lesions were slightly painful. Small hyperkeratotic papules were also observed on finger pads. Physical examination also revealed some aphthae affecting the lips. No other systemic symptoms were reported. A skin biopsy and blood tests were performed due to presumed chilblain LE with probable systemic involvement. Histology revealed basal vacuolar damage and intense perivascular and periadnexal lymphocytic inflammatory dermal infiltrate. Remarkably, mucin was noted among the collagen bundles. Leukopenia and positive ANA antibodies (titre 1:320) were detected. Complement levels were normal. SARS-CoV2 infection was ruled out. Skin lesions disappeared within 1 month under topical corticosteroids. Hydroxychloroquine was afterwards started by Rheumatology without recurrence of skin symptoms until last follow-up. Discussion(s): We present an uncommon case of an adolescent with systemic LE presenting as chilblain LE. Chilblain LE can be accompanied by other discoid CCLE. It can progress to systemic LE in up to 20% of patients, especially when concomitant CCLE is present. This rare presentation of CCLE should be differentiated from typical chilblain and other resembling lesions, such as SARS-CoV2-associated chilblain and acral purpuric lesions (COVID toes). The Mayo Clinic diagnostic criteria can be helpful, particularly in this last SARS-CoV2 outbreak scenario, when the reporting of similar skin lesions has been significant.

Robust, efficient workflow to establish, culture, and functionally assess primary-isolated airway epithelial cells

Background: Air-liquid interface (ALI) and organoid culture are key techniques for differentiating human airway epithelial cells (HAECs). The efficiency and robustness of these assays often depends on the quality of primary-isolated cells, but primary cell isolation workflows, with which the user controls the choice of isolation method, cell culture medium, and culture format, may reduce reproducibility. Therefore, an optimized, standardized workflow can enhance and support isolation of epithelial cells from diseased donors with potentially rare cystic fibrosis (CF) mutations or particularly sensitive cell populations. We have developed a standardized workflow for isolation and culture of freshly derived airway epithelial cells. Method(s): Briefly, HAECs isolated from primary tissue were expanded in PneumaCult-Ex Plus Medium for 1 week and then seeded into Corning Transwell inserts and expanded until confluency. The cells were then differentiated in PneumaCult-ALI Medium for at least 4 weeks. To assess differentiation efficiency in ALI culture, the cells were immunostained to detect Muc5AC, acetylated tubulin, and ZO-1 to identify goblet cells, ciliated cells, and apical tight junctions, respectively, aswell as SARS-CoV-2 cell entry targets angiotensin-converting enzyme 2 and transmembrane serine protease 2. Ion transport and barrier function of the ALI culturesand response to CF transmembrane conductance regulator (CFTR) correctors were also measured. In addition, freshly derived HAECs were seeded into Corning Matrigel domes in the presence of PneumaCult Airway Organoid Seeding Medium. Oneweek later, the mediumwas changed to PneumaCult Airway Organoid Differentiation Medium and maintained for an additional 3 weeks to promote cell differentiation. These airway organoids were then treated with CFTR corrector VX-809 for 24 hours, followed by 6-hour treatment with amiloride, forskolin, and genistein to induce organoid swelling. Result(s): Our results demonstrate that ALI cultures derived from CF donors displayed partial rescue of CFTR across multiple passages after treatment with VX-809. Airway organoids were found to express functional CFTR, as evidenced by forskolin treatment, which induced a 64 +/- 14% (n = 1 donor) greater organoid area than in vehicle control-treated airway organoids. Airway organoids derived from CF donors displayed a loss of forskolininduced swelling, which could be partially re-established with VX-809 treatment (29 +/- 9%, n = 3). Conclusion(s): In summary, the PneumaCult workflow supports robust, efficient culture of primary-airway epithelial cells that can be used as physiologically relevant models suitable for CF research, CFTR corrector screening, and studying airway biology.Copyright © 2022, European Cystic Fibrosis Society. All rights reserved

Mucin-Inspired Single-Chain Polymer (MIP) Fibers as Potent SARS-CoV-2 Inhibitors.

Mucins are the key component of the defensive mucus barrier. They are extended fibers of very high molecular weight with diverse biological functions depending strongly on their specific structural parameters. Here, we present a mucin-inspired nanostructure, produced via a synthetic methodology to prepare methacrylate-based dendronized polysulfates (MIP-1) on a multi gram-scale with high molecular weight (MW=450 kDa) and thiol end-functionalized mucin-inspired polymer (MIP) via RAFT polymerization. Cryo-electron tomography (Cryo-ET) analysis of MIP-1 confirmed a mucin-mimetic wormlike single-chain fiber structure (length=144±59 nm) in aqueous solution. This biocompatible fiber showed promising activity against SARS-CoV-2 and its mutant strain, with a remarkable low half maximal (IC50 ) inhibitory concentration (IC50 =10.0 nM). Additionally, we investigate the impact of fiber length on SARS-CoV-2 inhibition by testing other functional polymers (MIPs) of varying fiber lengths.

Nanopore single-molecule analysis of biomarkers: Providing possible clues to disease diagnosis

Biomarker detection has attracted increasing interest in recent years due to the minimally or non-invasive sampling process. Single entity analysis of biomarkers is expected to provide real-time and accurate biological information for early disease diagnosis and prognosis, which is critical to the effective disease treatment and is also important in personalized medicine. As an innovative single entity analysis method, nanopore sensing is a pioneering single-molecule detection technique that is widely used in analytical bioanalytical fields. In this review, we overview the recent progress of nanopore biomarker detection as new approaches to disease diagnosis. In highlighted studies, nanopore was focusing on detecting biomarkers of different categories of communicable and noncommunicable diseases, such as pandemic COVID-19, AIDS, cancers, neurologic diseases, etc. Various sensitive and selective nanopore detecting strategies for different types of biomarkers are summarized. In addition, the challenges, opportunities, and direction for future development of nanopore-based biomarker sensors are also discussed.Copyright © 2023 Elsevier B.V.

Differentially expressed FOXO1, NFE2L2 and NFKB1 mRNAs are associated with differentially regulated corona- and influenza viral receptor genes and Toll-like receptor pathway genes in human bronchial epithelial cells under hyperbaric oxygen exposure

As hyperbaric oxygen (HBO) has been shown to mitigate the COVID-19 symptoms, we were interested in studying whether HBO exposure affects expression of viral entry genes and innate immune genes in the air-liquid interface (ALI)-cultured human bronchial epithelial cells (HBECs) derived from normal individuals (NHBECs) and age-matched COPD patients (DHBECs), which were cultured under normoxia or daily exposure of 40-min hyperbaric oxygen (HBO) with 100% O2 at 2.5 ATA for 28 days in total. We found for the first time that HBO exposure differentially regulated mucociliary differentiation of HBECs by respectively decreasing and increasing expression of CGRP, MUC5AC, FOXJ1, NOTCH3 and HEYL in NHBECs and DHBECs, and respectively decreased and increased FOXO1 expression whereas increased and decreased NFE2L2 and NFKB1 expression in NHBECs and DHBECs, in association with respectively decreased and increased expression the SARS-CoV-2 entry genes ACE2 and 2 TMPRSS2 and the tight junction protein genes TJP1 and TJP2, and in association with respectively increased and decreased expression of the cell growth and inflammatory transcription factors SRF, c-FOS and TP63, as well as the TLR pathway genes TLR3, AKT1, IL-1B, IL-5, IL-6, IL-33, IRAK4 and NFKBIA in NHBECs and DHBECs. (Figure Presented).

SARS-CoV-2 infection and smoking: What is the association? A brief review.

Susceptibility to severe illness from COVID-19 is anticipated to be associated with cigarette smoking as it aggravates the risk of cardiovascular and respiratory illness, including infections. This is particularly important with the advent of a new strain of coronaviruses, the severe acute respiratory syndrome coronavirus (SARS-CoV-2) that has led to the present pandemic, coronavirus disease 2019 (COVID-19). Although, the effects of smoking on COVID-19 are less described and controversial, we presume a link between smoking and COVID-19. Smoking has been shown to enhance the expression of the angiotensin-converting enzyme-2 (ACE-2) and transmembrane serine protease 2 (TMPRSS2) key entry genes utilized by SARS-CoV-2 to infect cells and induce a 'cytokine storm', which further increases the severity of COVID-19 clinical course. Nevertheless, the impact of smoking on ACE-2 and TMPRSS2 receptors expression remains paradoxical. Thus, further research is necessary to unravel the association between smoking and COVID-19 and to pursue the development of potential novel therapies that are able to constrain the morbidity and mortality provoked by this infectious disease. Herein we present a brief overview of the current knowledge on the correlation between smoking and the expression of SARS-CoV-2 key entry genes, clinical manifestations, and disease progression.

Prevalence and Mechanisms of Mucus Accumulation in COVID-19 Lung Disease.

Rationale: The incidence and sites of mucus accumulation and molecular regulation of mucin gene expression in coronavirus (COVID-19) lung disease have not been reported. Objectives: To characterize the incidence of mucus accumulation and the mechanisms mediating mucin hypersecretion in COVID-19 lung disease. Methods: Airway mucus and mucins were evaluated in COVID-19 autopsy lungs by Alcian blue and periodic acid-Schiff staining, immunohistochemical staining, RNA in situ hybridization, and spatial transcriptional profiling. Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)-infected human bronchial epithelial (HBE) cultures were used to investigate mechanisms of SARS-CoV-2-induced mucin expression and synthesis and test candidate countermeasures. Measurements and Main Results: MUC5B and variably MUC5AC RNA concentrations were increased throughout all airway regions of COVID-19 autopsy lungs, notably in the subacute/chronic disease phase after SARS-CoV-2 clearance. In the distal lung, MUC5B-dominated mucus plugging was observed in 90% of subjects with COVID-19 in both morphologically identified bronchioles and microcysts, and MUC5B accumulated in damaged alveolar spaces. SARS-CoV-2-infected HBE cultures exhibited peak titers 3 days after inoculation, whereas induction of MUC5B/MUC5AC peaked 7-14 days after inoculation. SARS-CoV-2 infection of HBE cultures induced expression of epidermal growth factor receptor (EGFR) ligands and inflammatory cytokines (e.g., IL-1α/ß) associated with mucin gene regulation. Inhibiting EGFR/IL-1R pathways or administration of dexamethasone reduced SARS-CoV-2-induced mucin expression. Conclusions: SARS-CoV-2 infection is associated with a high prevalence of distal airspace mucus accumulation and increased MUC5B expression in COVID-19 autopsy lungs. HBE culture studies identified roles for EGFR and IL-1R signaling in mucin gene regulation after SARS-CoV-2 infection. These data suggest that time-sensitive mucolytic agents, specific pathway inhibitors, or corticosteroid administration may be therapeutic for COVID-19 lung disease.

Evaluation of Tcell exhaustion based on the expression of EOMES, Tbet and co-inhibitory receptors in severe and non-severe covid-19 patients.

During viral infections, especially Covid-19, Tcell exhaustion plays a crucial role in reducing the activity of lymphocytes and the immune system's antiviral activities. This research aimed to investigate the co-inhibitory receptors and transcription factors involved in the Tcell exhaustion process in ICU-admitted (ICUA) compared to non-ICU admitted (non-ICUA) Covid-19 patients. A total of 60 Covid-19 patients (30 patients in the severe group who were admitted in the ICU (ICUA) and 30 patients in the mild group who were admitted in departments other than the ICU (non-ICUA)) and 10 healthy individuals were included in this study. Laboratory tests and the level of gene expressions related to 4 inhibitory co-receptors, including LAG-3, TIM-3, TIGIT, PD-1, and T-bet and Eomes transcription factors involved in the process of Tcell exhaustion in severe and mild patients of Covid-19 were investigated. The results showed lymphopenia and an increase in other hematologic laboratory factors such as NLR, PLR, CRP, ALT, and AST in people with a severe form of the disease (ICUA) compared to mild groups (non-ICUA) (P < 0.001). Furthermore, a significant increase in 3 co-inhibitory receptors, TIM-3, LAG-3, and PD-1, was observed in severe patients compared to mild and healthy people (P < 0.001). An increase in TIGIT gene expression was lesser than the other three mentioned receptors (P < 0.05). Concerning the transcription factors, we observed a significant increase in Eomes in ICUA patients compared to the non-ICUA group (P < 0.001), and this increment in T-bet gene expression was minor compared to Eomes (P < 0.05). In conclusion, Patients with a severe form of acute respiratory syndrome coronavirus 2 (SARS-CoV-2) represented a higher level of gene expressions in terms of co-inhibitory receptors and transcription factors involved in the T cell exhaustion process.

Synthetic Mucin Gels with Self-Healing Properties Augment Lubricity and Inhibit HIV-1 and HSV-2 Transmission.

Mucus is a self-healing gel that lubricates the moist epithelium and provides protection against viruses by binding to viruses smaller than the gel's mesh size and removing them from the mucosal surface by active mucus turnover. As the primary nonaqueous components of mucus (≈0.2%-5%, wt/v), mucins are critical to this function because the dense arrangement of mucin glycans allows multivalence of binding. Following nature's example, bovine submaxillary mucins (BSMs) are assembled into "mucus-like" gels (5%, wt/v) by dynamic covalent crosslinking reactions. The gels exhibit transient liquefaction under high shear strain and immediate self-healing behavior. This study shows that these material properties are essential to provide lubricity. The gels efficiently reduce human immunodeficiency virus type 1 (HIV-1) and genital herpes virus type 2 (HSV-2) infectivity for various types of cells. In contrast, simple mucin solutions, which lack the structural makeup, inhibit HIV-1 significantly less and do not inhibit HSV-2. Mechanistically, the prophylaxis of HIV-1 infection by BSM gels is found to be that the gels trap HIV-1 by binding to the envelope glycoprotein gp120 and suppress cytokine production during viral exposure. Therefore, the authors believe the gels are promising for further development as personal lubricants that can limit viral transmission.

Rapid and Highly Sensitive Method for Evaluating Surface Coatings against an Enveloped RNA Virus.

The COVID-19 pandemic has increased public health vigilance worldwide. The coronavirus (SARS-CoV-2) can spread via aerosols, and droplet-borne viruses remain viable on nonliving surfaces for long duration. Hence, effective antiviral coatings are highly useful in eliminating viral persistence on nonliving surfaces. Although innovative antiviral coatings have been designed, conventional procedures for antiviral assays are generally laborious, time-consuming, and have a high limit of detection. In the present study, we report a rapid and highly sensitive method for evaluating antiviral coatings by measuring the luciferase activity derived from recombinant Sendai virus (SeV). The physicochemical characteristics of SeV, which has a single-stranded RNA genome encapsulated within a lipid envelope, allow us to exploit it as an indicator of the physicochemical potential of coating materials against enveloped RNA viruses in general. We demonstrate that SeV-based assay systems allow for the rapid and quantitative evaluation of the surface coatings composed of iodine solubilized in polyvinyl acetate. Additionally, we have investigated the effect of mucins, the dominant protein component of saliva, on the antiviral activity of surface coatings. The presence of mucins in the SeV suspension considerably rescues luciferase activity at the viral-surface interface, presumably due to mucin-mediated viral protection. Our findings provide insights into a procedure capable of the rapid evaluation and optimization of surface coatings, and suggest an important role of the mucin in the valid evaluation of antiviral agents.

Multimerization of Ebola GPΔmucin on protein nanoparticle vaccines has minimal effect on elicitation of neutralizing antibodies.

Ebola virus (EBOV), a member of the Filoviridae family of viruses and a causative agent of Ebola Virus Disease (EVD), is a highly pathogenic virus that has caused over twenty outbreaks in Central and West Africa since its formal discovery in 1976. The only FDA-licensed vaccine against Ebola virus, rVSV-ZEBOV-GP (Ervebo®), is efficacious against infection following just one dose. However, since this vaccine contains a replicating virus, it requires ultra-low temperature storage which imparts considerable logistical challenges for distribution and access. Additional vaccine candidates could provide expanded protection to mitigate current and future outbreaks. Here, we designed and characterized two multimeric protein nanoparticle subunit vaccines displaying 8 or 20 copies of GPΔmucin, a truncated form of the EBOV surface protein GP. Single-dose immunization of mice with GPΔmucin nanoparticles revealed that neutralizing antibody levels were roughly equivalent to those observed in mice immunized with non-multimerized GPΔmucin trimers. These results suggest that some protein subunit antigens do not elicit enhanced antibody responses when displayed on multivalent scaffolds and can inform next-generation design of stable Ebola virus vaccine candidates.

Caged Dexamethasone/Quercetin Nanoparticles, Formed of the Morphogenetic Active Inorganic Polyphosphate, are Strong Inducers of MUC5AC.

Inorganic polyphosphate (polyP) is a widely distributed polymer found from bacteria to animals, including marine species. This polymer exhibits morphogenetic as well as antiviral activity and releases metabolic energy after enzymatic hydrolysis also in human cells. In the pathogenesis of the coronavirus disease 2019 (COVID-19), the platelets are at the frontline of this syndrome. Platelets release a set of molecules, among them polyP. In addition, the production of airway mucus, the first line of body defense, is impaired in those patients. Therefore, in this study, amorphous nanoparticles of the magnesium salt of polyP (Mg-polyP-NP), matching the size of the coronavirus SARS-CoV-2, were prepared and loaded with the secondary plant metabolite quercetin or with dexamethasone to study their effects on the respiratory epithelium using human alveolar basal epithelial A549 cells as a model. The results revealed that both compounds embedded into the polyP nanoparticles significantly increased the steady-state-expression of the MUC5AC gene. This mucin species is the major mucus glycoprotein present in the secreted gel-forming mucus. The level of gene expression caused by quercetin or with dexamethasone, if caged into polyP NP, is significantly higher compared to the individual drugs alone. Both quercetin and dexamethasone did not impair the growth-supporting effect of polyP on A549 cells even at concentrations of quercetin which are cytotoxic for the cells. A possible mechanism of the effects of the two drugs together with polyP on mucin expression is proposed based on the scavenging of free oxygen species and the generation of ADP/ATP from the polyP, which is needed for the organization of the protective mucin-based mucus layer.

COVID-19 Survivor Patients Carrying the Rs35705950 Risk Allele in MUC5B Have Higher Plasma Levels of Mucin 5B.

BACKGROUND: Genetic susceptibility to infectious diseases is partly due to the variation in the human genome, and COVID-19 is not the exception. This study aimed to identify whether risk alleles of known genes linked with emphysema (SERPINA1) and pulmonary fibrosis (MUC5B) are associated with severe COVID-19, and whether plasma mucin 5B differs according to patients' outcomes. MATERIALS AND METHODS: We included 1258 Mexican subjects diagnosed with COVID-19. We genotyped rs2892474 and rs17580 of the SERPINA1 gene and rs35705950 of MUC5B. Based on the rs35705950 genotypes, mucin 5B plasma protein levels were quantified. RESULTS: Homozygous for the risk alleles of the three polymorphisms were found in less than 5% of the study population, but no statistically significant difference in the genotype or allele association analysis. At the protein level, non-survivors carrying one or two copies of the risk allele rs35705950 in MUC5B (GT + TT) had lower levels of mucin 5B compared to the survivors (0.0 vs. 0.17 ng/mL, p = 0.0013). CONCLUSION: The polymorphisms rs28929474 and rs17580 of SERPINA1 and rs35705950 of MUC5B are not associated with the risk of severe COVID-19 in the Mexican population. COVID-19 survivor patients bearing one or two copies of the rs35705950 risk allele have higher plasma levels of mucin 5B.

Interactive Web-Based Lung Cell Atlases Lower Barriers to Transcriptomic Data Sharing, Mining and Dissemination

Rationale: Recent advancements in sequencing technologies have led to a substantial increase in the scale and resolution of transcriptomic data. Despite this progress, accessibility to this data, particularly among those who are coming from non-computational backgrounds is limited. To facilitate improved access and exploration of our single-cell RNA sequencing data, we generated several data sharing, mining and dissemination portals to accompany our idiopathic pulmonary fibrosis (IPF), chronic obstructive pulmonary disease (COPD), and lung endothelial cells (Lung EC) cell atlases. Descriptions and links of each website can be found here: https://medicine.yale.edu/lab/kaminski/research/atlas/. Methods: Each interactive data mining website is coded in the R language using the Shiny package and is hosted by Shinyapps.io. Percell expression data for each website is stored on a MySQL database hosted by Amazon Web Services (AWS). Time-associated website engagement statistics and gene query information is collected for each website using a combination of Google Analytics and a gene search table stored on our MySQL database. User exploration of available data is facilitated through several easy-touse visualization tools available on each website. Results: Website usage statistics since the publication of each website shows that 9,772 unique users from 56 countries and five continents have accessed at least one of the three websites. At the time of writing, 300,748 total queries have been made for 15,627 unique genes across the websites. The top five searched genes for the IPF Cell Atlas are CD14, ACE2, ACTA2, IL11 and MUC5B while for the COPD Cell Atlas they are FAM13A, MIRLET7BHG, HHIP, ISM1 and DDT. Finally, the top searched genes for the Lung Endothelial Cell Atlas are BMPR2, PECAM1, EDNRB, APLNR and PROX1. Of note, interaction with the IPF Cell Atlas increased dramatically at the start of the COVID-19 pandemic, with queries for the ACE2 gene, the putative binding receptor for the SARS-CoV-2 virus, increasing substantially at the pandemic's onset in the United States. Conclusions: Usage statistics, gene query information and feedback from users, both within academia and industry, have shown broad engagement with our websites by individuals across computational and non-computational backgrounds. We envision widespread adoption of web-based portals similar to ours will facilitate novel discoveries within these complex datasets and new scientific collaborations.

Induced Pluripotent Stem Cell Derived Airway to Assess Cystic Fibrosis Intrinsic Epithelial Response to SARS-CoV-2

Rationale There is a lack of knowledge of how CFTR-deficient airway epithelium intrinsically responds to SARS-CoV-2. Though prior work has demonstrated altered CF airway expression of viral entry factors, it is unknown whether these alterations are protective and whether they reflect host genetic variation or secondary response of chronic inflammation. We address this gap by infecting induced pluripotent stem cell (iPSC)-derived airways from CF patients and syngeneic CFTR-corrected controls with SARS-CoV-2 and assessing differential susceptibility to infection and inflammatory and anti-viral response. MethodsCF (F508del homozygous) and syngeneic CFTR-corrected (CRISPR-Cas9) iPSC- were differentiated into airway epithelium cultured at airliquid interface (ALI) by a directed differentiation protocol that generates a pure population of major and rare airway cell-types. After 21 days in ALI culture, the iPSC-airway were infected with either mock or SARS-CoV-2 (isolate USA-WA1/2020) with MOI of 4, and harvested at 0, 1, 3 days post infection (dpi) for RT-PCR and immune-stainingResultsBoth CF and CFTR-corrected iPSC-airway express viral entry factors of ACE2 and TMPRSS2, and are permissive to SARS-CoV-2 infection. CF iPSC-airway exhibited significantly increase in SARS-CoV-2 nucleocapsid protein (N) transcript at 1 dpi, accompanied by increases in IFN2, RSAD2, and CXCL10 at 3 dpi, compared to its CFTR-corrected counter-part. There are no baseline significant differences in ACE2, TMPRSS2, TP63, NGFR, MUC5B, MUC5AC, SCGB1A1, FOXJ1, FOXI1 expression between CF and CFTR-corrected iPSC-airway before SARS-CoV-2 infection. ConclusionsOur preliminary studies indicate increased early SARS-CoV-2 infection in CFTR-deficient epithelium with accompanied subsequent rise in anti-viral and inflammatory response compared to its genetically controlled CFTR-corrected counterpart. Future studies are aimed at assessing differential CF epithelial kinetics of SARS-CoV-2 viral entry and replication, morphological changes, global transcriptomic response, and how treatment with CFTRmodulator would alter the epithelial response. Ultimately, we aim to establish a reductionist, physiologically relevant model system that is coupled with gene-editing technology to study intrinsic CF epithelial response to SARS-CoV-2, which would generate insights to aid practice guidelines for CF patients, and open future directions to evaluate gene-specific mechanisms of airway response to pathogens. (Figure Presented).

A Validation Study on a Sputum Home Collection Method with Immediate Freezing and Delayed Processing: Impact on Proteomic, Mucin and RNA/DNA Endpoints

Introduction: Due to Covid-19 restrictions on collecting and processing sputum samples in real time in clinic, we designed a novel sputum home collection method with immediate freezing and delayed processing (“home”). A validation study was carried out to compare key sputum endpoints using the “home” vs “real time (RT)” collection and processing methods. Sputum soluble phase proteomics, mucins and RNA/DNA endpoints were measured and compared between the 2 methods to assess the validity of the “home” method. Methods: Spontaneous sputum samples were collected from N=10 healthy adult volunteers. Each sample was split evenly by weight and processed, half by the “home” method and half by the RT method. Home method samples were first aliquoted into 3 collection tubes (T) as follows: T1: 100-250mg for mucin analysis (refractive index, gel chromatography, and CsCl gradients);T2 and T3: equal weights each, T2 for proteomic analysis (MesoScale Discovery) and T3 for RNA/DNA analysis (Isohelix collection kit). Each was immediately frozen at -20 deg C (24-48hr), then at -80 deg C (2-4 weeks) without any processing. Thawed home T1 and T2 samples were processed by treating with 8M Urea (1:1) to deactivate SARS-CoV-2 if present. T1 was then stored at 2-4 deg C, and T2 was processed with 7x DPBS, centrifuged and recovered supernatants stored at -80 deg C. In contrast, the RT sputum was first treated with 8M Urea (1:1) soon after collection, and then processed for mucins and proteomics per the “home” method above. The remaining cell pellet from the RT processed sample was stored in Zymo research RNA/DNA shield (0.5ml) and, along with home T3 samples, extracted and analyzed for qualitative and quantitative yield, as well as for genes of interest. Paired T-Test analysis compared all sputum endpoints between the home and RT method. Results: There were no statistically significant differences (p<0.05) between the home and RT method for any mucin (MUC5B, MUC5AC, MUC5AC:MUC5B ratio, total mucin) or proteomic endpoint (IL-1a, IL-6, IL-8, TNFalpha, TIMP1, TIMP2, MMP-9, CRP, MPO). In addition, except for CRP and MUC5AC, correlation between sample pairings was strong (correlation coefficient R, range = 0.5-0.9) and statistically significant (p<0.05) for all sputum endpoints. RNA/DNA results are still pending. Conclusion: The sputum “home collection method with immediate freezing and delayed processing” does not result in significantly different proteomic and mucin measurements when compared to the same samples being processed in real time in an identical manner.

Recent Advances in Mucoadhesive Interface Materials, Mucoadhesion Characterization, and Technologies

Mucoadhesion is an extremely important field of adhesion science and the comprehensive understanding and modulation of mucoadhesion can lead to lifesaving materials and technologies. For instance, deadly cases of COVID-19 (SARS-CoV-2) cytokine storm are associated with viral adhesion and overproduction of mucus, which obstructs the airways. Mucin is the key polymeric compound that is known as a family of high molecular weight, heavily glycosylated proteins in epithelial tissues. Mucoadhesion can occur in many different ways such as receptor specific and charge interactions, covalent or noncovalent bonds. New mucin-mimic polymers that replicate its beneficial traits can prevent biofilm formation and biofouling not only in biotechnology but also in membrane technologies. This review addresses the latest understandings related to mucin's role in wet adhesion considering different physiological conditions and shows how this translates into interfacial polymer adhesion. Advances in mucoadhesion measurement techniques including the rheological aspects of polymer-mucin adhesive interactions are presented. Specific mucoadhesive systems are discussed such as hydrogel mucoadhesion, catechol/dopamine functionalization, and polymeric nanoparticles. This overview may expand the current understanding of mucoadhesion between soft materials but also contributes to elastocapillary phenomena in soft materials design and applications such as new membranes, drugs, pharmaceutical devices, and lubricated surfaces.

A novel approach to concentrate human and animal viruses from wastewater using receptors-conjugated magnetic beads.

Viruses are present at low concentrations in wastewater; therefore, an effective method for concentrating virus particles is necessary for accurate wastewater-based epidemiology (WBE). We designed a novel approach to concentrate human and animal viruses from wastewater using porcine gastric mucin-conjugated magnetic beads (PGM-MBs). We systematically evaluated the performances of the PGM-MBs method (sensitivity, specificity, and robustness to environmental inhibitors) with six viral species, including Tulane virus (a surrogate for human norovirus), rotavirus, adenovirus, porcine coronavirus (transmissible gastroenteritis virus or TGEV), and two human coronaviruses (NL63 and SARS-CoV-2) in influent wastewater and raw sewage samples. We determined the multiplication factor (the ratio of genome concentration of the final solution to that of the initial solution) for the PGM-MBs method, which ranged from 1.3 to 64.0 depending on the viral species. Because the recovery efficiency was significantly higher when calculated with virus titers than it was with genome concentration, the PGM-MBs method could be an appropriate tool for assessing the risk to humans who are inadvertently exposed to wastewater contaminated with infectious viruses. Furthermore, PCR inhibitors were not concentrated by PGM-MBs, suggesting that this tool will be successful for use with environmental samples. In addition, the PGM-MBs method is cost-effective (0.5 USD/sample) and has a fast turnaround time (3 h from virus concentration to genome quantification). Thus, this method can be implemented in high throughput facilities. Because of its strong performance, intrinsic characteristics of targeting the infectious virus, robustness to wastewater, and adaptability to high throughput systems, the PGM-MBs method can be successfully applied to WBE and ultimately provides valuable public health information.

Krebs von den Lungen-6 (KL-6) as a clinical marker for severe COVID-19: A systematic review and meta-analyses.

BACKGROUND: Krebs von den Lungen-6 (KL-6) is a molecule that is predominantly expressed by damaged alveolar type II cells, and has been proposed as a marker of COVID-19 and the severity of the disease. Here, we performed a meta-analysis to determine whether KL-6 could be used as a prognostic factor for severe COVID-19. METHODS: PubMed, Cochrane and Google Scholar were searched until April 20, 2021, and 7 studies were included. KL-6 was considered as the outcome and pooled in meta-analyses. RESULTS: All included studies compared KL-6 in severe and non-severe patients. Serum KL-6 was higher in severe COVID-19 patients compared to non-severe (n = 6; SMD = 1.25; 95% CI: 0.99-1.5; P < 0.001) and healthy controls (n = 4; SMD = 3.07; 95% CI: 1.36-4.8; P < 0.001). CONCLUSION: This data collection revealed the potential clinical significance of KL-6 as a non-expensive predictive biomarker in severe COVID-19 and for the categorization of COVID-19 clinical severity.