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Moninger, T. O.

Publications and source records attributed to Moninger, T. O..

3 recordsLinked to original sources

Defining Functional Correction Thresholds in Primary Ciliary Dyskinesia for Effective Gene Therapies

RationalePrimary ciliary dyskinesia (PCD) is an inherited disorder characterized by defective motile cilia and impaired mucociliary clearance. Mutations in CCDC40 disrupt axonemal organization, resulting in dyskinetic or immotile cilia. While emerging therapies may restore function in only a subset of cells, the functional consequences of mixed populations of mutant and healthy cilia are not well understood. ObjectivesTo determine how defined mixtures of CCDC40-deficient and wild-type ciliated cells influence mucociliary transport. MethodsHuman bronchial epithelial cells were combined at varying ratios of CCDC40-deficient and wild-type cells and differentiated to model heterogeneous epithelia. High-speed video microscopy and particle-tracking algorithms were used to assess ciliary motion and mucus transport and combined with electron microscopy to evaluate cilia ultrastructure. Measurements and Main ResultsAirway differentiation was largely preserved with marked ultrastructural defects observed in CCDC40 cells, including multiple central centrioles, absent inner dynein arms, and basal body misorientation. Ciliated surface coverage decreased, and goblet coverage increased with higher mutant representation. Mucociliary transport declined nonlinearly, with speeds dropping from [~]56 {micro}m/s (100% WT) to [~]9 {micro}m/s in 100% mutant cultures. Clearance-per-beat and flow coordination decreased sharply with rising mutant burden. Modeling revealed that transport efficiency was equivalent to that recorded in ex vivo human tissues and plateaued when [~]75% of the ciliated population was WT. ConclusionsTogether, these findings define a PCD-specific functional correction threshold and show that effective therapy must overcome the disruptive biomechanical and cellular influences of mutant epithelial cells, providing a quantitative benchmark to guide gene-therapy design and clinical translation.

cell biology↗

Development and Initial Characterization of Pigs with DNAI1 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. As with many other diseases, a better understanding of pathogenic mechanisms may lead to effective treatments. To pursue disease mechanisms, we used CRISPR-Cas9 to develop a PCD pig with a disrupted DNAI1 gene. PCD pig airway cilia lacked the outer dynein arm and had impaired beating. MCT was impaired under both baseline conditions and after cholinergic stimulation in PCD pigs. Neonatal PCD pigs developed neonatal respiratory distress with evidence of atelectasis, air trapping, and airway mucus obstruction. Despite airway mucus accumulation, lung bacterial counts were similar between neonatal wild-type and PCD pigs. Sinonasal disease was present in all neonatal PCD pigs. Older PCD pigs developed worsening airway mucus obstruction, inflammation, and bacterial infection. This pig model closely mimics the disease phenotype seen in people with PCD and can be used to better understand the pathophysiology of PCD airway disease.

physiology↗

ISG15-modification of the Arp2/3 complex restricts pathogen spread

The ubiquitin-like protein, ISG15, can act as a cytokine or can covalently modify host and pathogen-derived proteins. The consequences of ISG15 modification on substrate fate remain unknown. Here we reveal that ISGylation of the Arp2/3 complex slows actin filament formation and stabilizes Arp2/3 dependent structures including cortical actin and lamella. When properly controlled, this serves as an antibacterial and antiviral host defense strategy to directly restrict actin-mediated pathogen spread. However, Listeria monocytogenes takes advantage in models of dysregulated ISGylation, leading to increased mortality due to augmented spread. The underlying molecular mechanism responsible for the ISG15-dependent impact on actin-based motility is due to failed bacterial separation after division. This promotes spread by enabling the formation of multi-headed bacterial "bazookas" with stabilized comet tails that can disseminate deeper into tissues. A bacterial mutant that cannot recruit Arp2/3 or a non-ISGylatable mutant of Arp3 is sufficient to rescue slowed comet tail speed and restrict spread. Importantly, ISG15-deficient neonatal mice have aberrant epidermal epithelia characterized by keratinocytes with diffuse cortical actin, which could underlie observed defects in wound healing in human patients who lack ISG15. Ultimately, our discovery links host innate immune responses to cytoskeletal dynamics with therapeutic implications for viral infection and metastasis.

cell biology↗