The Complex Association between COPD and COVID-19.

Chronic obstructive pulmonary disease (COPD) is significant cause of morbidity and mortality worldwide. There is mounting evidence suggesting that COPD patients are at increased risk of severe COVID-19 outcomes; however, it remains unclear whether they are more susceptible to acquiring SARS-CoV-2 infection. In this comprehensive review, we aim to provide an up-to-date perspective of the intricate relationship between COPD and COVID-19.

Type 2 Immunity and Its Impact on COVID-19 Infection in the Airways.

Type 2 immune responses are characterized by elevated type 2 cytokines and blood eosinophilia. Emerging evidence suggests that people with chronic type 2 inflammatory lung diseases are not particularly susceptible to SARS-CoV-2 infection. Intriguingly, recent in vitro, ex vivo research demonstrates type 2 cytokines, particularly IL-13, reduce the risk of SARS-CoV-2 infection in the airway epithelium.

Molecular Dynamics and Theratyping in Airway and Gut Organoids Reveal R352Q-CFTR Conductance Defect.

A significant challenge to making targeted cystic fibrosis transmembrane conductance regulator (CFTR) modulator therapies accessible to all individuals with cystic fibrosis (CF) are many mutations in the gene that can cause CF, most of which remain uncharacterized. Here, we characterized the structural and functional defects of the rare mutation R352Q, with a potential role contributing to intrapore chloride ion permeation, in patient-derived cell models of the airway and gut. CFTR function in differentiated nasal epithelial cultures and matched intestinal organoids was assessed using an ion transport assay and forskolin-induced swelling assay, respectively.

Molecular dynamics and functional characterization of I37R-CFTR lasso mutation provide insights into channel gating activity.

Characterization of I37R, a mutation located in the lasso motif of the CFTR chloride channel, was conducted by theratyping several CFTR modulators from both potentiator and corrector classes. Intestinal current measurements in rectal biopsies, forskolin-induced swelling (FIS) in intestinal organoids, and short circuit current measurements in organoid-derived monolayers from an individual with I37R/F508del CFTR genotype demonstrated that the I37R-CFTR results in a residual function defect amenable to treatment with potentiators and type III, but not type I, correctors. Molecular dynamics of I37R using an extended model of the phosphorylated, ATP-bound human CFTR identified an altered lasso motif conformation which results in an unfavorable strengthening of the interactions between the lasso motif, the regulatory (R) domain, and the transmembrane domain 2 (TMD2).

Significant functional differences in differentiated Conditionally Reprogrammed (CRC)- and Feeder-free Dual SMAD inhibited-expanded human nasal epithelial cells.

Background: Patient-derived airway cells differentiated at Air Liquid Interface (ALI) are valuable models for Cystic fibrosis (CF) precision therapy. Different culture expansion methods have been established to extend expansion capacity of airway basal cells, while retaining functional airway epithelium physiology. Considerable variation in response to CFTR modulators is observed in cultures even within the same CFTR genotype and despite the use of similar ALI culture techniques.

An open-source high-content analysis workflow for CFTR function measurements using the forskolin-induced swelling assay.

Motivation: The forskolin-induced swelling (FIS) assay has become the preferential assay to predict the efficacy of approved and investigational CFTR-modulating drugs for individuals with cystic fibrosis (CF). Currently, no standardized quantification method of FIS data exists thereby hampering inter-laboratory reproducibility.

Results: We developed a complete open-source workflow for standardized high-content analysis of CFTR function measurements in intestinal organoids using raw microscopy images as input.

Novel Antioxidant Therapy with the Immediate Precursor to Glutathione, γ-Glutamylcysteine (GGC), Ameliorates LPS-Induced Cellular Stress in In Vitro 3D-Differentiated Airway Model from Primary Cystic Fibrosis Human Bronchial Cells.

Systemic glutathione deficiency, inflammation, and oxidative stress are hallmarks of cystic fibrosis (CF), an inherited disease that causes persistent lung infections and severe damage to the respiratory system and many of the body organs. Improvements to current antioxidant therapeutic strategies are needed. The dietary supplement, γ-glutamylcysteine (GGC), which is the immediate precursor to glutathione, rapidly boosts cellular glutathione levels following a single dose in healthy individuals.

Human Primary Epithelial Cell Models: Promising Tools in the Era of Cystic Fibrosis Personalized Medicine.

Cystic fibrosis (CF) is an inherited disorder where individual disease etiology and response to therapeutic intervention is impacted by CF transmembrane regulator (CFTR) mutations and other genetic modifiers. CFTR regulates multiple mechanisms in a diverse range of epithelial tissues. In this Review, we consolidate the latest updates in the development of primary epithelial cellular model systems relevant for CF.

The effect of premature termination codon mutations on CFTR mRNA abundance in human nasal epithelium and intestinal organoids: a basis for read-through therapies in cystic fibrosis.

A major challenge in cystic fibrosis (CF) research is applying mutation-specific therapy to individual patients with diverse and rare CF transmembrane conductance regulator (CFTR) genotypes. Read-through agents are currently the most promising approach for Class I mutations that introduce premature termination codons (PTCs) into CFTR mRNA. However, variations in degradation of PTC containing transcripts by nonsense mediated decay (NMD) might lower read-through efficacy.

R560S: A class II CFTR mutation that is not rescued by current modulators.

Background: New therapies modulating defective CFTR have started to hit the clinic and others are in trial or under development. The endeavour of drug discovery for CFTR protein rescue is however difficult one since over 2000 mutations have been reported. For most of these, especially the rare ones, the associated defects, the respective functional class and their responsiveness to available modulators are still unknown.

Partial rescue of F508del-cystic fibrosis transmembrane conductance regulator channel gating with modest improvement of protein processing, but not stability, by a dual-acting small molecule.

Background And Purpose: Rescue of F508del-cystic fibrosis (CF) transmembrane conductance regulator (CFTR), the most common CF mutation, requires small molecules that overcome protein processing, stability and channel gating defects. Here, we investigate F508del-CFTR rescue by CFFT-004, a small molecule designed to independently correct protein processing and channel gating defects.

Experimental Approach: Using CFTR-expressing recombinant cells and CF patient-derived bronchial epithelial cells, we studied CFTR expression by Western blotting and channel gating and stability with the patch-clamp and Ussing chamber techniques.

A novel microscopy-based assay identifies extended synaptotagmin-1 (ESYT1) as a positive regulator of anoctamin 1 traffic.

An attractive possibility to treat Cystic Fibrosis (CF), a severe condition caused by dysfunctional CFTR, an epithelial anion channel, is through the activation of alternative (non-CFTR) anion channels. Anoctamin 1 (ANO1) was demonstrated to be a Ca-activated chloride channel (CaCC) and thus of high potential to replace CFTR. Despite that ANO1 is expressed in human lung CF tissue, it is present at the cell surface at very low levels.

The third dimension: new developments in cell culture models for colorectal research.

Cellular models are important tools in various research areas related to colorectal biology and associated diseases. Herein, we review the most widely used cell lines and the different techniques to grow them, either as cell monolayer, polarized two-dimensional epithelia on membrane filters, or as three-dimensional spheres in scaffold-free or matrix-supported culture conditions. Moreover, recent developments, such as gut-on-chip devices or the ex vivo growth of biopsy-derived organoids, are also discussed.

Measurements of Functional Responses in Human Primary Lung Cells as a Basis for Personalized Therapy for Cystic Fibrosis.

Background: The best investigational drug to treat cystic fibrosis (CF) patients with the most common CF-causing mutation (F508del) is VX-809 (lumacaftor) which recently succeeded in Phase III clinical trial in combination with ivacaftor. This corrector rescues F508del-CFTR from its abnormal intracellular localization to the cell surface, a traffic defect shared by all Class II CFTR mutants. Our goal here is to test the efficacy of lumacaftor in other Class II mutants in primary human bronchial epithelial (HBE) cells derived from CF patients.

Protein traffic disorders: an effective high-throughput fluorescence microscopy pipeline for drug discovery.

Plasma membrane proteins are essential molecules in the cell which mediate interactions with the exterior milieu, thus representing key drug targets for present pharma. Not surprisingly, protein traffic disorders include a large range of diseases sharing the common mechanism of failure in the respective protein to reach the plasma membrane. However, specific therapies for these diseases are remarkably lacking.