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Ryu, M. H.

Publications and source records attributed to Ryu, M. H..

4 recordsLinked to original sources

Characterization of tri-culture alveolar-like organoids to study fibrotic lung diseases

Rationale: Fibrotic interstitial lung diseases are progressive disorders characterized by lung scarring and declining respiratory function. Repeated injury and dysregulated epithelial-mesenchymal crosstalk are implicated in disease pathogenesis but remain incompletely understood. Three-dimensional (3D) organoids incorporating epithelial-mesenchymal crosstalk provide a physiologically relevant platform for investigating these mechanisms. Here, we present a 3D tri-co-culture alveolar organoid model and evaluate its responses to two profibrotic stimuli, TGF-{beta} and bleomycin. Methods: CI-huArlo, NCI-H441, and MRC-5 cells were co-cultured for 14 days to generate alveolar-like organoids. Cell marker expression was assessed by immunofluorescence (IF). To test injury response, organoids were exposed to TGF-{beta} (50 ng/mL) or bleomycin (20 g/mL) for 48 hours and characterized. Supernatants were collected to assess interleukin 8 (IL-8) and procollagen I by ELISA. qPCR assessed expression of CDKN1A and COL1A1 following treatments. Bulk RNA sequencing (RNA-seq) evaluated the transcriptomic responses to fibrotic stimulus. Results: Cellular marker expression was confirmed using IF for aquaporin-5 (alveolar type I cell marker) and TE-7 (fibroblast marker). Bleomycin exposure reduced viability and significantly increased IL-8 (126.3 {+/-} 16.86 vs. 48.88 {+/-} 4.470 pg/mL; p = 0.0002; N=6), with no change in secreted procollagen I compared to control. TGF-{beta} stimulation significantly increased secreted procollagen I (149.6 {+/-} 27.07 vs. 53.38 {+/-} 5.672 pg/mL; p <0.0001; N=6) without affecting viability or IL-8 release. qPCR resulted in no change in CDKN1A expression, while COL1A1 expression was increased with TGF-{beta} treatment compared with control and bleomycin. RNA sequencing demonstrated distinct and reproducible transcriptional responses to TGF-{beta} and bleomycin. TGF-{beta} induced 750 significantly upregulated and 641 downregulated genes, including increased COL1A1, COL4A1, FN1, and TGFB1, with enrichment of epithelial-mesenchymal transition and TGF-{beta} signalling programs. In contrast, bleomycin induced 953 significantly upregulated and 552 downregulated genes relative to untreated controls and was characterized by p53 signalling, DNA-damage responses, and reduced cell-cycle progression. Reference-state analysis further indicated reduced normal alveolar epithelial signatures following both treatments, with TGF-{beta} producing the strongest aberrant basaloid and myofibroblast-associated signatures. Conclusions: Tri-culture alveolar-like organoids exhibited stimulus-specific responses in a 3D multicellular system, supporting their use for mechanistic studies of epithelial-mesenchymal crosstalk, environmental exposures, and therapeutic responses.

cell biology↗

miRNA-mRNA network analysis identifies PAX5 as a potential regulator of adaptive immune response in COPD

Micro-ribonucleic acids (miRNAs) are key post-transcriptional regulators of the immune system and may play a role in Chronic Obstructive Pulmonary Disease (COPD). In this paper, we constructed subject-specific miRNA-mRNA regulatory networks using bulk and deconvoluted whole blood RNA-sequencing, whole blood miRNA-sequencing, and B-cell receptor-sequencing data from up to 570 miRNAs, 11,859 mRNAs, and 3,190 participants in the COPDGene study. Analysis of whole blood networks revealed two subnetworks of miRNA-mRNA interactions significantly (FDR<0.05) associated with changes in FEV1/FVC. We found that miRNAs (and mRNAs) in the network-identified groups had distinct expression patterns, with miRNAs (and mRNAs) in one group having overall higher expression in COPD (decreasing FEV1/FVC) and miRNAs (and mRNAs) in the other group having overall higher expression in controls (increasing FEV1/FVC). In addition, miRNAs (and mRNAs) within the same group were positively correlated, while those in different groups were negatively correlated, indicating distinct functional roles for these miRNAs (and mRNAs) as a function of increased COPD severity. Network analysis also identified PAX5, a transcription factor master regulator of B-cell development, as the main mRNA network hub. Using ChIP-seq data in lymphoblastoid cells, we identified a PAX5 binding site overlapping with a COPD genome-wide association signal in the promoter region of ADAM19. We also found a loss of co-expression between PAX5 and ADAM19 in COPD subjects. Furthermore, in B-cell deconvoluted data, PAX5 was differentially co-expressed with genes associated with B-cell activation and differentiation, revealing a possible mechanism for the regulation of the immune response in COPD. Finally, in B-cell receptor sequencing data, PAX5 and the identified mRNA subnetworks were negatively associated (FDR<0.05) with immunoglobulin class switching, and positively associated with IgM and IgD counts. In conclusion, PAX5 is a known regulator of B-cell identity. B cells are recognized as key players in chronic inflammation and immune dysregulation in COPD. Our work suggests that PAX5 plays a mediating role both in ADAM19 regulation and in miRNA regulation of early B cells in COPD.

systems biology↗

Woodsmoke and Diesel Exhaust: Distinct Transcriptomic Profiles in the Human Airway Epithelium

Climate change is increasing the frequency and severity of wildfires globally, causing significant woodsmoke (WS) emissions. Vehicles emit sizable amounts of toxic traffic-related air pollution (TRAP), for which diesel exhaust (DE) is a model. Both WS and DE contain particulate matter <2.5 microns (PM2.5) which deeply penetrates the lungs, causing respiratory epithelial inflammation that drives health effects. Regulations focus on PM2.5 concentration, despite emerging research that highlights how composition mediates health effects. As WS and DE are compositionally distinct, we conducted the first head-to-head comparison of effects on the transcriptomes of air-liquid interface cultured primary human bronchial epithelial cells (HBEC). Differentiated donor-matched HBEC transwells were exposed for 2-hours to filtered air (FA; control), or WS (furnace tube burning pine) or DE (Hatz 1B30E generator) both diluted to 300 {micro}g/m3 of PM2.5. WS had higher ultrafine PM, whereas DE exposure contained significantly higher NO2, CO, and O3. RNA sequencing showed that WS exposure resulted in 119 ({uparrow}41, {downarrow}78) differentially expressed genes, while DE modulated 399 ({uparrow}255, {downarrow}144) compared to FA exposure. WS was associated with small ribosomal subunit and cytochrome complex related genes, while DE exposure was associated with HIF-1 signaling, respiratory chain complex and interferon alpha/beta signaling/ISG15-protein conjugation, suggesting how TRAP exposure may enhance infection risk. We also analyzed exposure effects on protein immune-mediators. We demonstrate that two major air pollution sources modulate different genes and pathways in HBECs, with minimal overlap. This informs the debate regarding the regulatory focus on concentration and assumptions that similar concentrations of air pollution have indistinct effects. HighlightsO_LILung health effects of diesel exhaust (DE) and wood smoke (WS) are underexplored C_LIO_LIRNAseq of DE and WS-exposed primary lung epithelial cells revealed larger DE effects C_LIO_LIDE showed greater repression of host antiviral response-associated genes than WS C_LIO_LIA regulatory focus on PM concentration may miss composition-specific lung effects C_LI

bioinformatics↗

Expression of the endocannabinoid system in the human airway epithelial cells: Impact of sex and chronic respiratory disease status

Recreational and medicinal cannabis consumption in the past 12 months has been reported in 1/5th of Canadians, with greater use in males relative to females. Cannabis smoking is the dominant route of delivery in consumers, with the airway epithelium functioning as the site of first contact for inhaled phytocannabinoids. The endocannabinoid system is responsible for mediating the physiological effects of inhaled phytocannabinoids. Acute cannabis smoke inhalation can result in bronchodilation, which may have applications in chronic respiratory disease management. In contrast, chronic cannabis smoke inhalation is associated with reduced lung function and bronchitis, which challenges potential applications in the lung. The contribution of the endocannabinoid system in the airway epithelium to either beneficial or harmful physiological responses remains to be clearly defined in males and females and those with underlying chronic respiratory disease. To begin to address this knowledge gap, a curated dataset of 1090 unique human bronchial brushing gene expression profiles was created from Gene Expression Omnibus deposited microarray datasets. The dataset included 616 healthy subjects, 136 subjects with asthma, and 338 subjects with COPD. A 27-gene endocannabinoid signature was analyzed across all samples with sex and disease specific-analyses performed. Immunohistochemistry and immunoblots were performed to confirm in situ and in vitro protein expression of select genes in human airway epithelial cells. We confirm three receptors for cannabinoids, CB1, CB2, and TRPV1, are expressed at the protein level in human airway epithelial cells in situ and in vitro, justifying examining the downstream endocannabinoid pathway more extensively at the gene expression level. Sex status was associated with differential expression of 6/27 genes. In contrast, disease status was associated with differential expression of 18/27 genes in asthmatics and 22/27 genes in COPD subjects. We confirm at the protein level that TRPV1, the most differentially expressed candidate in our analyses, was up-regulated in airway epithelial cells from asthmatics relative to healthy subjects. Our data demonstrate that endocannabinoid system is expressed in human airway epithelial cells with expression impacted by disease status and minimally by sex. The data suggest that cannabis consumers may have differential physiological responses in the respiratory mucosa, which could impact both acute and chronic effects of cannabis smoke inhalation.

cell biology↗