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Latzin, P.

Publications and source records attributed to Latzin, P..

4 recordsLinked to original sources

Tracking eco-evolutionary dynamics among lung pathobiome members from children with cystic fibrosis

Polymicrobial lung infections are common in individuals with cystic fibrosis (CF). Pathogen communities typically follow an ecological succession in which early colonizers such as Haemophilus influenzae and Staphylococcus aureus are later joined by Pseudomonas aeruginosa. Although adaptation to the lung environment is well described for single pathogens in adult people with CF, much less is known about the role of pathogen interactions and how changes in individual pathogens influence community dynamics at the early stages of disease. To address these questions, we combined genome sequencing with phenotypic screens and pathogen interaction assays using longitudinal clinical isolates (19 P. aeruginosa, 44 S. aureus, and 21 H. influenzae) collected from 23 children with CF (0-7.9 years of age) enrolled in the SCILD (Swiss CF Infant Lung Development) cohort. Our analysis revealed that early pathogen communities are characterized by a combination of strain turnover and persistence of isolates undergoing first steps of within-host evolution. Most notably, quorum-sensing-deficient P. aeruginosa variants repeatedly emerged, showing reduced protease production and diminished inhibition of S. aureus and H. influenzae. These changes indicate that P. aeruginosa becomes less antagonistic towards co-occurring pathogens, possibly promoting community stability. Together, our results show that ecological and evolutionary dynamics between pathobiome members may play an underappreciated role in shaping CF lung disease during early childhood.

evolutionary biology↗

Proteomic and structural comparison between cilia from primary ciliary dyskinesia patients with a DNAH5 defect

Primary ciliary dyskinesia (PCD) is a genetic disorder that affects the motile cilia in various organs, leading to recurrent respiratory infections, subfertility, and laterality abnormalities. Traditional diagnostic methods include high-speed video microscopy, immunofluorescence staining, electron microscopy, and genetic screening. However, how different disease-causing variants in the same PCD gene affect clinical presentation, as well as ciliary composition and structure, is not well understood. We investigated the effect of various mutations in DNAH5, an axonemal dynein heavy chain, using mass spectrometry and cryo-electron tomography. We demonstrated differences in the axonemal composition for patients with dnah5 mutations. Furthermore, we showed that reductions in some ciliary components are patient specific. Some of them, KIAA1430, CFAP97, and DTHD1, were not previously recognized as components of human respiratory motile cilia. Finally, we demonstrated that some differences in protein abundance between wild-type and PCD samples can be observed in the 96-nm repeated unit of the axoneme. Our results suggest that many axonemal components are affected in the DNAH5-defective samples. Additionally, our results highlight that disparate mutations have seemingly distinctive consequences for the axonemal composition.

cell biology↗

Spirometric indices in primary ciliary dyskinesia: systematic review and meta-analysis

Primary ciliary dyskinesia (PCD) is a genetic, heterogeneous disease caused by dysfunction of cilia. Evidence is sparse and reports of lung function of PCD patients ranges from normal to severe impairment. This systematic review and meta-analysis of studies of lung function of PCD patients examines the spirometric indices of PCD patients and differences by age group and sex.\n\nWe searched PubMed, Embase, and Scopus for studies that described lung function in [≥]10 patients with PCD. We performed meta-analyses and metaregression to explain heterogeneity. We included 24 studies, ranging from 13-158 patients per study. The most commonly reported spirometric indices were forced expiratory volume in 1 sec (FEV1) and forced vital capacity (FVC) presented as mean and standard deviation of percent of predicted values. We found considerable heterogeneity for both parameters (I2 range 94-96%). The heterogeneity remained when we stratified the analysis by age; however, FEV1 in adult patients was lower. Even after taking into account explanatory factors, the largest part of the between-studies variance remained unexplained. Heterogeneity could be explained by genetic differences between study populations, methodological factors related to the variability of study inclusion criteria, or details on the performance and evaluation of lung function measurements that we could not account for. Prospective studies therefore need to use standardised protocols and international reference values. These results underline the possibility of distinct PCD phenotypes as in other chronic respiratory diseases. Detailed characterisation of these phenotypes and related genotypes is needed in order to better understand the natural history of PCD.

epidemiology↗

The Swiss Primary Ciliary Dyskinesia registry: objectives, methods and first results

Primary Ciliary Dyskinesia (PCD) is a rare hereditary, multi-organ disease caused by defects in ciliary structure and function. It results in a wide range of clinical manifestations, most commonly in the upper and lower airways. Central data collection in national and international registries is essential to studying the epidemiology of rare diseases and filling in gaps in knowledge of diseases such as PCD. For this reason, the Swiss Primary Ciliary Dyskinesia Registry (CH-PCD) was founded in 2013 as a collaborative project between epidemiologists and adult and paediatric pulmonologists.\n\nThe registry records patients of any age, suffering from PCD, who are treated and resident in Switzerland. It collects information from patients identified through physicians, diagnostic facilities, and patient organisations. The registry dataset contains data on diagnostic evaluations, lung function, microbiology and imaging, symptoms, treatments, and hospitalizations.\n\nBy May 2018, CH-PCD has contacted 566 physicians of different specialties and identified 134 patients with PCD. At present this number represents an overall 1 in 63,000 prevalence of people diagnosed with PCD in Switzerland. Prevalence differs by age and region; it is highest in children and adults younger than 30 years, and in Espace Mittelland. The median age of patients in the registry is 25 years (range 5-73), and 49 patients have a definite PCD diagnosis based on recent international guidelines. Data from CH-PCD are contributed to international collaborative studies and the registry facilitates patient identification for nested studies.\n\nCH-PCD has proven to be a valuable research tool that already has highlighted weaknesses in PCD clinical practice in Switzerland. Development of centralised diagnostic and management centres and adherence to international guidelines are needed to improve diagnosis and management--particularly for adult PCD patients.

epidemiology↗