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Twan, W. K.

Publications and source records attributed to Twan, W. K..

3 recordsLinked to original sources

Comparative Single-Cell Transcriptomics Uncovers Shared and Distinct Molecular Signatures in Cystic Fibrosis and Primary Ciliary Dyskinesia

RationalCystic Fibrosis (CF) and Primary Ciliary Dyskinesia (PCD) are both inherited respiratory disorders that result in impaired mucociliary clearance, and chronic sinopulmonary disease. Although the current approach to PCD management is extrapolated from CF care, both conditions arise from distinct genetic and molecular mechanisms. MethodsHere we performed a comparative transcriptomic analysis between CF and PCD to compare the cellular heterogeneity, molecular pathways and gene networks differences using publicly available sequencing data as well as those performed by our group. To explore gene regulatory networks, a pre-trained transformer model (scGPT) was fine-tuned using an integrated dataset, and differential attention analysis was conducted to identify genes and pathways with altered attention scores between the two conditions. ResultsThe comparative transcriptomic analysis revealed distinct molecular signatures between PCD and CF, which differed from normal cells. In ciliated cells, differential gene expression and pathway investigation highlighted the NRF2 pathways considerable overrepresentation in PCD compared to CF and healthy conditions. This observation was further supported by scGPT analysis, which revealed increased incoming attention to the NRF2 pathway markers. In secretory cells, PCD and CF exhibited increased immune and inflammatory signaling compared to controls. While similar inflammatory processes were active, results suggested a stronger inflammatory pattern in CF secretory cells compared to PCD and confirmed the activation of the unfolded protein response (UPR) pathway. ConclusionThese findings highlight the different molecular signatures between both conditions and the need for unique approaches to management in PCD compared to CF.

cell biology↗

Machine Learning Analysis of Cilia-Driven Particle Transport Distinguishes Primary Ciliary Dyskinesia Cilia from Normal Cilia

RationalPrimary ciliary dyskinesia (PCD) is a genetic condition that results in dysmotile cilia and abnormal mucociliary clearance. Despite advances in understanding the pathogenesis of PCD, diagnosis continues to be challenging. Here we used feature-based machine learning and image-based deep learning to objectively quantify the directed particle transport of motile cilia and detect PCD-related cilia dysfunction. MethodsFluorescent microspheres were captured on cultured multiciliated cells using high-speed video microscopy as a proxy for motile cilia function. An interactive Jython script was designed to automatically detect, track and extract raw track metrics from videos. Data was subsequently analyzed to approximate a quantifiable and visual signature of ciliary transport through a custom-built Python Package, CiliaTracks. ResultsAirway epithelial cells were obtained from 14 individuals with genetically confirmed PCD, 10 healthy donors, and 2 patients with cystic fibrosis. A total of 602 videos (301 PCD and 301 non-PCD) were captured. Quantitative and visual analyses of fluorescent microsphere trajectories, including kinematic metrics and trajectory plots, revealed distinct motility profiles between PCD and non-PCD samples. Classical machine learning models and a convolutional neural network were employed to classify PCD using both modalities, demonstrating excellent accuracy of 95-97%, and the capacity to differentiate PCD from normal cells or cystic fibrosis. ConclusionCilia-propelled microsphere transport exhibits unique trajectory patterns in PCD, enabling differentiation from non-PCD samples. Machine learning provides an objective and accurate framework for characterizing ciliary dysfunction, offering potential as a diagnostic tool for PCD.

bioinformatics↗

Localization and function of key axonemal microtubule inner proteins and dynein docking complex members reveal extensive diversity among vertebrate motile cilia

Vertebrate motile cilia are broadly classified as (9+2) or (9+0), based on the presence or absence of the central pair apparatus, respectively. Cryogenic electron microscopy (cryo-EM) analyses of (9+2) cilia have uncovered an elaborate axonemal protein composition; whether these features are relevant to (9+0) cilia remain unclear. We previously demonstrated that Cfap53, a key microtubule inner protein (MIP) as well as centriolar-satellites component, is essential for motility of (9+0), but not (9+2) cilia. Here, we show that in (9+2) cilia, Cfap53 functions redundantly with a paralogous MIP, Mns1. Mns1 localizes to ciliary axonemes, and combined loss of both proteins in zebrafish and mice, caused severe loss of outer dynein arms (ODAs) of (9+2) cilia, significantly affecting their motility. Moreover, using immunoprecipitation, we demonstrate that while Mns1 can self-associate and interact with Cfap53, Cfap53 is unable to self-associate. Finally, we show that multiple additional dynein interacting proteins, such as the ODA docking complex (ODA-DC) members, show strikingly distinct localization patterns between various motile cilia-types. Our findings clarify how paralogous MIPs, Cfap53 and Mns1, function in regulating motility of (9+2) versus (9+0) cilia, and establish that localization pattern of other key motility proteins also differ between these cilia-types, further emphasizing extensive structural variations among these organelles.

developmental biology↗