Residential fungal β-(1,3)-D-glucan exposure is associated with decreased pulmonary function in fibrotic pulmonary sarcoidosis.

Background: Sarcoidosis is a multi-system disease frequently affecting the lungs. It is thought to be mediated by gene-environment interaction; for example, epidemiological data show organic aerosol exposure increases risk of pulmonary sarcoidosis.

Research Question: Does exposure to bioaerosol associate with worse lung disease in patients with pulmonary sarcoidosis?

Research Question: Using an observational, cohort study design, we measured residential exposure to fungal and bacterial cell wall material, β-(1,3)-D-glucan (BDG) and endotoxin, respectively, in healthy control subjects and those with pulmonary sarcoidosis.

IL-13 induces loss of CFTR in ionocytes and reduces airway epithelial fluid absorption.

The airway surface liquid (ASL) plays a crucial role in lung defense mechanisms, and its composition and volume are regulated by the airway epithelium. The cystic fibrosis transmembrane conductance regulator (CFTR) is abundantly expressed in a rare airway epithelial cell type called an ionocyte. Recently, we demonstrated that ionocytes can increase liquid absorption through apical CFTR and basolateral barttin/chloride channels, while airway secretory cells mediate liquid secretion through apical CFTR channels and basolateral NKCC1 transporters.

Development and Initial Characterization of Pigs with Mutations and Primary Ciliary Dyskinesia.

Mutations in more than 50 different genes cause primary ciliary dyskinesia (PCD) by disrupting the activity of motile cilia that facilitate mucociliary transport (MCT). Knowledge of PCD has come from studies identifying disease-causing mutations, characterizing structural cilia abnormalities, finding genotype-phenotype relationships, and studying the cell biology of cilia. Despite these important findings, we still lack effective treatments and people with PCD have significant pulmonary impairment.

IL-13 decreases susceptibility to airway epithelial SARS-CoV-2 infection but increases disease severity in vivo.

Treatments available to prevent progression of virus-induced lung diseases, including coronavirus disease 2019 (COVID-19) are of limited benefit once respiratory failure occurs. The efficacy of approved and emerging cytokine signaling-modulating antibodies is variable and is affected by disease course and patient-specific inflammation patterns. Therefore, understanding the role of inflammation on the viral infectious cycle is critical for effective use of cytokine-modulating agents.

A predominately pulmonary activation of complement in a mouse model of severe COVID-19.

Evidence from in vitro studies and observational human disease data suggest the complement system plays a significant role in SARS-CoV-2 pathogenesis, although how complement dysregulation develops in patients with severe COVID-19 is unknown. Here, using a mouse-adapted SARS-CoV-2 virus (SARS2-N501Y) and a mouse model of severe COVID-19, we identify significant serologic and pulmonary complement activation following infection. We observed C3 activation in airway and alveolar epithelia, and in pulmonary vascular endothelia.

Epithelial responses to CFTR modulators are improved by inflammatory cytokines and impaired by antiinflammatory drugs.

Cystic fibrosis (CF) is a genetic disorder that disrupts CF transmembrane conductance regulator (CFTR) anion channels and impairs airway host defenses. Airway inflammation is ubiquitous in CF, and suppressing it has generally been considered to improve outcomes. However, the role of inflammation in people taking CFTR modulators, small-molecule drugs that restore CFTR function, is not well understood.

Long-COVID improves in 50% of patients after a year in a Midwestern cohort.

Background: Many of those infected with COVID-19 experience long-term disability due to persistent symptoms known as Long-COVID, which include ongoing respiratory issues, loss of taste and smell, and impaired daily functioning.

Research Question: This study aims to better understand the chronology of long-COVID symptoms.

Study Design And Methods: We prospectively enrolled 403 adults from the University of Iowa long-COVID clinic (June 2020 to February 2022).

Eosinophil expression of triggering receptor expressed on myeloid cells 1 (TREM-1) restricts type 2 lung inflammation.

Asthma affects 25 million Americans, and recent advances in treatment are effective for only a portion of severe asthma patients. TREM-1, an innate receptor that canonically amplifies inflammatory signaling in neutrophils and monocytes, plays a central role in regulating lung inflammation. It is unknown how TREM-1 contributes to allergic asthma pathology.

Adaptation of SARS-CoV-2 to ACE2 mice reveals new spike residues that drive mouse infection.

The Coronavirus Disease 2019 (COVID-19) pandemic continues to cause extraordinary loss of life and economic damage. Animal models of severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2) infection are needed to better understand disease pathogenesis and evaluate preventive measures and therapies. While mice are widely used to model human disease, mouse angiotensin converting enzyme 2 (ACE2) does not bind the ancestral SARS-CoV-2 spike protein to mediate viral entry.

Increased ENaC-mediated liquid absorption across vitamin-D deficient human airway epithelia.

Vitamin D deficiency is a risk factor for exacerbation of obstructive airway disease, a hallmark of which is mucus dehydration and plugging. Calcitriol (the active form of vitamin D) deficiency in cultured human airway epithelia resulted in increased and mRNAs encoding subunits of ENaC and the Na-K pump compared with supplemented epithelia. These drive the absorption of airway surface liquid.

Interleukin 13-Induced Inflammation Increases DPP4 Abundance but Does Not Enhance Middle East Respiratory Syndrome Coronavirus Replication in Airway Epithelia.

Background: Chronic pulmonary conditions such as asthma and chronic obstructive pulmonary disease increase the risk of morbidity and mortality during infection with the Middle East respiratory syndrome coronavirus (MERS-CoV). We hypothesized that individuals with such comorbidities are more susceptible to MERS-CoV infection due to increased expression of its receptor, dipeptidyl peptidase 4 (DPP4).

Methods: We modeled chronic airway disease by treating primary human airway epithelia with the Th2 cytokine interleukin 13 (IL-13), examining how this affected DPP4 protein levels with MERS-CoV entry and replication.

DNA demethylation fine-tunes IL-2 production during thymic regulatory T cell differentiation.

Regulatory T (T reg) cells developing in the thymus are essential to maintain tolerance and prevent fatal autoimmunity in mice and humans. Expression of the T reg lineage-defining transcription factor FoxP3 is critically dependent upon T cell receptor (TCR) and interleukin-2 (IL-2) signaling. Here, we report that ten-eleven translocation (Tet) enzymes, which are DNA demethylases, are required early during double-positive (DP) thymic T cell differentiation and prior to the upregulation of FoxP3 in CD4 single-positive (SP) thymocytes, to promote Treg differentiation.

FXYD3 facilitates Na and liquid absorption across human airway epithelia by increasing the transport capacity of the Na/K ATPase.

Na/K ATPase activity is essential for ion transport across epithelia. FXYD3, a γ subunit of the Na/K ATPase, is expressed in the airway, but its function remains undetermined. Single-cell RNA sequencing and immunohistochemistry revealed that FXYD3 localizes within the basolateral membrane of all airway epithelial cells.

WNK Inhibition Increases Surface Liquid pH and Host Defense in Cystic Fibrosis Airway Epithelia.

In cystic fibrosis (CF), reduced HCO secretion acidifies the airway surface liquid (ASL), and the acidic pH disrupts host defenses. Thus, understanding the control of ASL pH (pH) in CF may help identify novel targets and facilitate therapeutic development. In diverse epithelia, the WNK (with-no-lysine [K]) kinases coordinate HCO and Cl transport, but their functions in airway epithelia are poorly understood.

Vitamin D-mediated effects on airway innate immunity in vitro.

Introduction: Vitamin D supplementation has been suggested to enhance immunity during respiratory infection season. We tested the effect of active vitamin D (calcitriol) supplementation on key airway innate immune mechanisms in vitro.

Methods: Primary human airway epithelial cells (hAECs) grown at the air liquid interface were supplemented with 10-7 M calcitriol for 24 hours (or a time course) and their antimicrobial airway surface liquid (ASL) was tested for pH, viscoscity, and antibacterial and antiviral properties.

Eicosanoid signalling blockade protects middle-aged mice from severe COVID-19.

Coronavirus disease 2019 (COVID-19) is especially severe in aged populations. Vaccines against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) are highly effective, but vaccine efficacy is partly compromised by the emergence of SARS-CoV-2 variants with enhanced transmissibility. The emergence of these variants emphasizes the need for further development of anti-SARS-CoV-2 therapies, especially for aged populations.

Quantitative Chest CT Assessment of Small Airways Disease in Post-Acute SARS-CoV-2 Infection.

Background The long-term effects of SARS-CoV-2 infection on pulmonary structure and function remain incompletely characterized. Purpose To test whether SARS-CoV-2 infection leads to small airways disease in patients with persistent symptoms. Materials and Methods In this single-center study at a university teaching hospital, adults with confirmed COVID-19 who remained symptomatic more than 30 days following diagnosis were prospectively enrolled from June to December 2020 and compared with healthy participants (controls) prospectively enrolled from March to August 2018.

A Single-Cell Atlas of Large and Small Airways at Birth in a Porcine Model of Cystic Fibrosis.

Lack of CFTR (cystic fibrosis transmembrane conductance regulator) affects the transcriptome, composition, and function of large and small airway epithelia in people with advanced cystic fibrosis (CF); however, whether lack of CFTR causes cell-intrinsic abnormalities present at birth versus inflammation-dependent abnormalities is unclear. We performed a single-cell RNA-sequencing census of microdissected small airways from newborn CF pigs, which recapitulate CF host defense defects and pathology over time. Lack of minimally affected the transcriptome of large and small airways at birth, suggesting that infection and inflammation drive transcriptomic abnormalities in advanced CF.

Cellular and molecular architecture of submucosal glands in wild-type and cystic fibrosis pigs.

Submucosal glands (SMGs) protect lungs but can also contribute to disease. For example, in cystic fibrosis (CF), SMGs produce abnormal mucus that disrupts mucociliary transport. CF is an ion transport disease, yet knowledge of the ion transporters expressed by SMG acini, which produce mucus, and SMG ducts that carry it to the airway lumen is limited.

Translating in vitro CFTR rescue into small molecule correctors for cystic fibrosis using the Library of Integrated Network-based Cellular Signatures drug discovery platform.

Cystic fibrosis (CF) is a lethal autosomal recessive disease caused by mutations in the cystic fibrosis transmembrane conductance regulator (CFTR) gene. The common ΔF508-CFTR mutation results in protein misfolding and proteasomal degradation. If ΔF508-CFTR trafficks to the cell surface, its anion channel function may be partially restored.

Performance of a scalable RNA extraction-free transcriptome profiling method for adherent cultured human cells.

RNA sequencing enables high-content/high-complexity measurements in small molecule screens. Whereas the costs of DNA sequencing and RNA-seq library preparation have decreased consistently, RNA extraction remains a significant bottleneck to scalability. We evaluate the performance of a bulk RNA-seq library prep protocol optimized for analysis of many samples of adherent cultured cells in parallel.

Lentiviral vectors transduce lung stem cells without disrupting plasticity.

Life-long expression of a gene therapy agent likely requires targeting stem cells. Here we ask the question: does viral vector transduction or ectopic expression of a therapeutic transgene preclude airway stem cell function? We used a lentiviral vector containing a GFP or cystic fibrosis transmembrane conductance regulator () transgene to transduce primary airway basal cells from human cystic fibrosis (CF) or non-CF lung donors and monitored expression and function after differentiation. Ussing chamber measurements confirmed CFTR-dependent chloride channel activity in CF donor cells.

Measles virus exits human airway epithelia within dislodged metabolically active infectious centers.

Measles virus (MeV) is the most contagious human virus. Unlike most respiratory viruses, MeV does not directly infect epithelial cells upon entry in a new host. MeV traverses the epithelium within immune cells that carry it to lymphatic organs where amplification occurs.