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Pezzulo, A. A.

Publications and source records attributed to Pezzulo, A. A..

9 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↗

In Utero CFTR Modulation Alleviates Disease in G551D Cystic Fibrosis Pigs

Previous studies indicate that pigs with CFTR-null and CFTR-{Delta}F508 mutations develop multiorgan disease similar to that in people with cystic fibrosis (CF). At birth, their airways exhibit host defense defects that predispose to airway infection, inflammation, and mucus accumulation. The CFTR-G551D mutation causes CF by producing CFTR channels that localize correctly but have reduced channel activity. Ivacaftor (VX-770) is a small molecule drug developed to potentiate CFTR activity. To test the phenotype of the CFTR-G551D mutation in pigs and determine whether ivacaftor can rescue CF abnormalities, we developed CFTRG551D/G551D (CF-G551D) pigs through homologous recombination in fetal fibroblasts and somatic cell nuclear transfer. Newborn CF-G551D piglets exhibited phenotypes similar to CF-null piglets, including meconium ileus, exocrine pancreatic destruction, micro-gallbladder, vas deferens destruction, and airway structural abnormalities. Compared to wild-type pigs, CF-G551D pigs had reduced forskolin-stimulated short-circuit current in airway and intestinal tissues. Ivacaftor increased the single-channel open state probability of CFTR-G551D and increased short-circuit current to near wild-type levels. Similar to our other CF pig models, we found that 100% of CF-G551D pigs were born with meconium ileus. To test whether in utero ivacaftor treatment could prevent or alleviate meconium ileus, pregnant sows were treated with ivacaftor beginning at day 35 of gestation and continuing until delivery. This treatment rescued the pancreas, gallbladder, and vas deferens phenotype in the majority of CF-G551D pigs. Animals that were spared from meconium ileus were able to survive without ivacaftor treatment. Airway disease developed similar to other CF pig models. These findings indicate that this model may be useful for studies in which CFTR function can be reversed, for investigating in utero CFTR correction strategies, and for longitudinal studies in CF pigs.

physiology↗

Acute malaria dysregulates specialized lymph node macrophages to suppress vaccine-elicited protection against Ebola virus

The filovirus, Ebola virus (EBOV), causes outbreaks of Ebola virus disease (EVD) throughout equatorial Africa. ERVEBO(R) (rVSV/EBOV) is a replication-competent, recombinant vesicular stomatitis virus (rVSV)-vectored vaccine licensed to control EVD outbreaks. EVD outbreaks occur in regions endemic for Plasmodium-caused malaria. Plasmodium infections persist due in part to the parasites ability to evade sterilizing immunity which also dampens immune responses to heterologous vaccines. Acute murine Plasmodium infection at the time of rVSV/EBOV vaccination reduced vaccine-mediated protection against mouse-adapted EBOV (ma-EBOV) challenge. Decreased protection was associated with a Plasmodium-induced interferon gamma (IFN-{gamma})-mediated decrease of rVSV/EBOV replication in lymph node (LN) macrophages, resulting in reduced primary anti-EBOV glycoprotein antibody responses. Higher doses of rVSV/EBOV partially overcame the antibody deficits and elicited protective responses. Evidence of the negative impact of Plasmodium on the efficacy of low dose rVSV/EBOV vaccine protocols supports the use of high antigen loads in effective management of EVD outbreaks. IMPORTANCEWe show that blood-stage murine Plasmodium infections negatively impacts the primary antibody response elicited by low dose rVSV/EBOV vaccination and results in reduced protection against a lethal dose of ma-EBOV. This defect occurs within the draining lymph node due to the elevation of IFN-{gamma} elicted in Py-infected mice. The Py-imposed decrease in vaccine-mediated protection can be overcome with higher doses of rVSV/EBOV. While the strong protection conferred by rVSV/EBOV and significant side effects known to be associated with this vaccine have led to the suggestion that the vaccine dosage be reduced19, our studies provide a rationale for maintaining a higher dose.

microbiology↗

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. We investigated the role of the type 2 cytokine IL-13 on SARS-CoV-2 binding/entry, replication, and host response in primary HAE cells in vitro and in a model of mouse-adapted SARS-CoV-2 infection in vivo. IL-13 protected airway epithelial cells from SARS-CoV-2 infection in vitro by decreasing the abundance of ACE2- expressing ciliated cells rather than by neutralization in the airway surface liquid or by interferon-mediated antiviral effects. In contrast, IL-13 worsened disease severity in mice; the effects were mediated by eicosanoid signaling and were abolished in mice deficient in the phospholipase A2 enzyme PLA2G2D. We conclude that IL-13-induced inflammation differentially affects multiple steps of COVID-19 pathogenesis. IL-13-induced inflammation may be protective against initial SARS-CoV-2 airway epithelial infection; however, it enhances disease progression in vivo. Blockade of IL-13 and/or eicosanoid signaling may be protective against progression to severe respiratory virus-induced lung disease. RESEARCH IN CONTEXTO_ST_ABSEvidence before this studyC_ST_ABSPrior to this study, various pieces of evidence indicated the significant role of cytokines in the pathogenesis and progression of COVID-19. Severe COVID-19 cases were marked by cytokine storm syndrome, leading to immune activation and hyperinflammation. Treatments aimed at modulating cytokine signaling, such as IL-6 receptor antagonists, had shown moderate effects in managing severe COVID-19 cases. Studies also revealed an excessive production of type 2 cytokines, particularly IL-13 and IL-4, in the plasma and lungs of COVID-19 patients, which was associated with adverse outcomes. Treatment with anti-IL-13 monoclonal antibodies improved survival following SARS-CoV-2 infection, suggesting that IL-13 plays a role in disease severity. Type 2 cytokines were observed to potentially suppress type 1 responses, essential for viral clearance, and imbalances between these cytokine types were linked to negative COVID-19 outcomes. These findings highlighted the complex interactions between cytokines and the immune response during viral infections, underscoring the importance of understanding IL-13s role in COVID-19 and related lung diseases for developing effective therapeutic interventions. Added value of this studyIn this study, we explored the impact of IL-13-induced inflammation on various stages of the SARS-CoV-2 infection cycle using both murine (in vivo) and primary human airway epithelial (in vitro) culture models. Our findings indicated that IL-13 provided protection to airway epithelial cells against SARS-CoV-2 infection in vitro, partly by reducing the number of ACE2- expressing ciliated cells. Conversely, IL-13 exacerbated the severity of SARS2-N501YMA30-induced disease in mice, primarily through Pla2g2d-mediated eicosanoid biosynthesis. Implications of the available evidenceCurrent evidence indicates that PLA2G2D plays a crucial role in the IL-13-driven exacerbation of COVID-19 in mice, suggesting that targeting the IL-13-PLA2G2D axis could help protect against SARS-CoV-2 infection. These insights are important for clinical research, especially for studies focusing on drugs that modify IL-13 signaling or modulate eicosanoids in the treatment of asthma and respiratory virus-induced lung diseases.

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↗

Topography-dependent gene expression and function of common cell archetypes in large and small porcine airways

The small airways of humans are affected early in several lung diseases. However, because they are relatively inaccessible, little is known about the epithelial cells that line these airways. We performed a single cell RNA-seq census of small and large airways of wild-type pigs and pigs with disrupted cystic fibrosis transmembrane conductance regulator (CFTR) gene. The sequencing data showed that small airway epithelia had similar major cell types as large airways but no ionocytes; moreover, lack of CFTR expression had minimal effect on the transcriptome. Small airway epithelial cells expressed a different transcriptome than large airway cells. Quantitative immunohistochemistry showed that small airway basal cells participate in epithelial barrier function. Finally, sequencing data and in vitro electrophysiologic studies suggest that small airway epithelia have a water and ion transport advantage. Our data highlight the archetypal nature of basal, secretory, and ciliated airway cells with location-dependent gene expression and function.

genomics↗

Performance of a scalable extraction-free RNA-seq method

RNA sequencing enables high-contents/high-complexity measurements in small molecule screens performed on biological samples. Whereas the costs of DNA sequencing and the complexity of RNA-seq library preparation and analysis have decreased consistently, RNA extraction remains a significant bottleneck for RNA-seq of hundreds of samples in parallel. Direct use of cell lysate for RNA-seq library prep is common in single cell RNA-seq but not in bulk RNA-seq protocols. Recently published protocols suggest that direct lysis is compatible with simplified RNA-seq library prep. Here, we evaluate the performance of a bulk RNA-seq library prep protocol optimized for analysis of many samples of adherent cultured cells in parallel. We combine a low-cost direct lysis buffer compatible with cDNA synthesis ("in-lysate cDNA synthesis") with Smart-3SEQ and examine the effects of calmidazolium and fludrocortisone-induced perturbation of primary human dermal fibroblasts. We compared this method to normalized purified RNA inputs from matching samples followed by Smart-3SEQ or Illumina TruSeq library prep. Our results show that whereas variable RNA inputs for each sample in the in-lysate cDNA synthesis protocol result in variable sequencing depth, this had minimal effect on data quality, measurement of gene expression patterns, or generation of differentially expressed gene lists. We found that in-lysate cDNA synthesis combined with Smart-3SEQ RNA-seq library prep allows generation of high-quality data when compared to library prep with extracted RNA, or when compared to Illumina TruSeq. Our data show that small molecule screens using RNA-seq are feasible at low reagent and time costs.

genomics↗

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 (CFTR) 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. Immunostaining, quantitative real-time PCR, and single-cell sequencing analysis of cell-type markers indicated that vector transduction or CFTR expression does not alter the formation of pseudostratified, fully-differentiated epithelial cell cultures or cell type distribution. These results have important implications for use of gene addition or gene editing strategies as life-long curative approaches for lung genetic diseases.

molecular biology↗

HSP90 inhibition modulates NFB signaling in airway goblet cell metaplasia

Goblet cell metaplasia and mucus hyper-production are key features of chronic muco-obstructive lung diseases such as asthma, chronic bronchitis, and cystic fibrosis. Various mechanisms lead to goblet cell metaplasia in the airways; the driving mechanism for goblet cell metaplasia in a specific patient may be unknown. We recently found that heat shock protein 90 (HSP90) is important for both IL-13- and IL-17- induced airway goblet cell metaplasia. HSP90 interacts with multiple clients that are important in goblet cell metaplasia including Akt, Jak/STAT, IRS, Notch, and various kinases involved in NF{kappa}B signaling. Here, we used a targeted phospho-proteomic approach to identify candidate HSP90 clients modulated by the HSP90-inhibitor geldanamycin. NF{kappa}B family members were enriched amongst the top candidate targets of HSP90 inhibition in IL-13 an organotypic model of human airway epithelia. We hypothesized that HSP90 inhibition modulated goblet cell metaplasia by interfering with NF{kappa}B signaling. We used transcription factor activation, nuclear translocation, and phospho-specific immunofluorescence assays to investigate how IL-13 exposure and HSP90 inhibition modulated NF{kappa}B. We found that HSP90 inhibition prevented goblet cell metaplasia by non-canonically blocking NF{kappa}B p100/p52 function in human airway epithelia. NF{kappa}B modulation via its interaction with HSP90 is a pharmaceutically feasible therapeutic target for goblet cell metaplasia; this approach may enable treatment of patients with chronic muco-inflammatory lung diseases with both known or unidentified disease-driving mechanisms.

cell biology↗