Age and environmental exposures influence the fecal bacteriome of young children with cystic fibrosis

Secondhand vape exposure regulation of CFTR and immune function in cystic fibrosis

Secondhand smoke exposure (SHSe) is a public health threat for people with cystic fibrosis (CF) and other lung diseases. Primary smoking reduces CF transmembrane conductance regulator (CFTR) channel function, the causative defect in CF. We reported that SHSe worsens respiratory and nutritional outcomes in CF by disrupting immune responses and metabolic signaling. Recently, electronic cigarette (e-cigs) usage by caregivers and peers has increased rapidly, causing new secondhand e-cig vape exposures. Primary vaping is associated with immunologic deficits in healthy people, but it is unknown whether e-cigs similarly impacts CF immune function or how it differs from SHSe. Human CF and non-CF blood monocyte-derived macrophages (MDMs) and bronchial epithelial cells (HBECs) were exposed to flavored and unflavored e-cigs. The effect of e-cigs on CFTR expression and function, bacterial killing, cytokine signaling, lipid mediators, and metabolism was measured during treatment with CFTR modulators. E-cigs decreased CFTR expression and function in CF and non-CF MDMs and negated CFTR functional restoration by elexacaftor/tezacaftor/ivacaftor (ETI). E-cigs also negated the restoration of anti-inflammatory PGD2 expression in CF MDMs treated with ETI compared with controls. Flavored but not unflavored e-cigs increased proinflammatory cytokine expression in CF MDMs and e-cigs promoted glycolytic metabolism. E-cigs did not impact bacterial killing. Overall, HBECs were less impacted by e-cigs compared with MDMs. E-cigs reduced macrophage CFTR expression and hindered functional CFTR restoration by CFTR modulators, promoting a glycolytic, proinflammatory state. E-cigs are an emerging public health threat that may limit the efficacy of CFTR modulators in people with CF.NEW & NOTEWORTHY New research reveals that e-cigarettes pose a serious health risk for individuals with cystic fibrosis (CF). Exposure to electronic cigarette (e-cig) vapors decreases CF transmembrane conductance regulator (CFTR) function and undermines the effectiveness of CFTR modulators, potentially worsening inflammation and metabolic responses. This highlights an urgent need for awareness around e-cig use, especially among caregivers and peers of those with CF. E-cigarettes may further complicate the management of this chronic lung disease.

Premodulator microbiome alterations associated with postmodulator growth outcomes in pediatric cystic fibrosis: Can we predict outcomes?

OBJECTIVES

The gut microbiota plays an important role in childhood growth. Our longitudinal cohort includes children with cystic fibrosis (CwCF) treated with highly effective modulator therapy. We aimed to elucidate early premodulator microbial signatures associated with postmodulator weight for CwCF later in childhood.

METHODS

Stool samples were collected from CwCF at 13 days to 60 months. Metagenomic sequencing determined differentially abundant taxa. Children with body mass index or weight for length Z-scores within 1 standard deviation of the mean (SD) were considered normal weight, those >1 SD were classified as risk of overweight while children <1 SD were considered undernourished, although no CwCF met this latter criterion here. Multivariate regression models were applied to identify significant associations between metadata and microbial taxonomic relative abundances.

RESULTS

One hundred and eighty-nine stool samples were analyzed from 39 CwCF. We identified statistically significant differences in early microbiome patterns among those at risk of being overweight compared to those who were normal weight when adjusted for age, sex, CF mutation, and early feeding method. Early microbiome was a stronger driver of growth status than current modulator use. Among those at risk of overweight, several taxa that were consistently in lower abundance included Eggerthella lentha, Ruminococcus, Bacteroides, with increase in abundance of Bacteroides stercoris.

CONCLUSIONS

The early microbiome strongly predicts growth in the setting of modulator use for CwCF and we identify microbiome signatures associated with risk of being overweight. We highlight the possibility for interventions or early alternations to nutritional guidance for prevention of comorbid complications.

Nasal airway inflammatory responses and pathogen detection in infants with cystic fibrosis

BACKGROUND

Detecting airway inflammation non-invasively in infants with cystic fibrosis (CF) is difficult. We hypothesized that markers of inflammation in CF [IL-1β, IL-6, IL-8, IL-10, IL-17A, neutrophil elastase (NE) and tumor necrosis factor (TNF-α)] could be measured in infants with CF from nasal fluid and would be elevated during viral infections or clinician-defined pulmonary exacerbations (PEx).

METHODS

We collected nasal fluid, nasal swabs, and hair samples from 34 infants with CF during monthly clinic visits, sick visits, and hospitalizations. Nasal fluid was isolated and analyzed for cytokines. Respiratory viral detection on nasal swabs was performed using the Luminex NxTAG® Respiratory Pathogen Panel. Hair samples were analyzed for nicotine concentration by reverse-phase high-performance liquid chromatography. We compared nasal cytokine concentrations between the presence and absence of detected respiratory viruses, PEx, and smoke exposure.

RESULTS

A total of 246 samples were analyzed. Compared to measurements in the absence of respiratory viruses, mean concentrations of IL-6, IL-8, TNF-α, and NE were significantly increased while IL-17A was significantly decreased in infants positive for respiratory viruses. IL-17A was significantly decreased and NE increased in those with a PEx. IL-8 and NE were significantly increased in infants with enteric pathogen positivity on airway cultures, but not P. aeruginosa or S. aureus. Compared to those with no smoke exposure, there were significantly higher levels of IL-6, IL-10, and NE in infants with detectable levels of nicotine.

CONCLUSIONS

Noninvasive collection of nasal fluid may identify inflammation in infants with CF during changing clinical or environmental exposures.

The relationship between the intestinal microbiome and body mass index in children with cystic fibrosis

BACKGROUND

The nutritional status of children with cystic fibrosis (CF), as assessed by their body mass index percentile (BMIp), is a critical determinant of long-term health outcomes. While the intestinal microbiome plays an important role in nutrition, little is known regarding the relationship of the microbiome and BMIp in children with CF.

METHODS

Pediatric patients (< 18 years old) with CF and healthy comparison patients (HCs) were enrolled in the study and stool samples obtained. BMIp was categorized as Green Zone (BMIp > 50th), Yellow Zone (BMIp 25th-49th) and Red Zone (BMIp < 25th). Intestinal microbiome assessment was performed via 16S rRNA gene sequencing; microbial richness, diversity, and differential species abundance were assessed.

RESULTS

Stool samples were collected from 107 children with CF and 50 age-matched HCs. Compared to HCs, children with CF were found to have lower bacterial richness, alpha-diversity, and a different microbial composition. When evaluating them by their BMIp color zone, richness and alpha-diversity were lowest in those in the Red Zone. In addition, an unclassified amplicon sequence variant (ASV) of Blautia, a known butyrate-producing anaerobe, was of lowest abundance in children in the Red Zone.

CONCLUSION

Children with CF have a dysbiotic intestinal microbiome with specific changes that accompany changes in BMIp. Longitudinal assessments of the microbiome and its metabolic activities over time are needed to better understand how improvements in the microbiome may improve nutrition and enhance long-term survival in children with CF.

Diagnosis and Management of Gastrointestinal Manifestations in Children with Cystic Fibrosis

Cystic fibrosis (CF) is primarily known for its pulmonary consequences, which are extensively explored in the existing literature. However, it is noteworthy that individuals with CF commonly display gastrointestinal (G-I) manifestations due to the substantial presence of the cystic fibrosis transmembrane conductance regulator (CFTR) protein in the intestinal tract. Recognized as pivotal nonpulmonary aspects of CF, G-I manifestations exhibit a diverse spectrum. Identifying and effectively managing these manifestations are crucial for sustaining health and influencing the overall quality of life for CF patients. This review aims to synthesize existing knowledge, providing a comprehensive overview of the G-I manifestations associated with CF. Each specific G-I manifestation, along with the diagnostic methodologies and therapeutic approaches, is delineated, encompassing the impact of innovative treatments targeting the fundamental effects of CF on the G-I tract. The findings underscore the imperative for prompt diagnosis and meticulous management of G-I manifestations, necessitating a multidisciplinary team approach for optimal care and enhancement of the quality of life for affected individuals. In conclusion, the authors emphasize the urgency for further clinical studies to establish a more robust evidence base for managing G-I symptoms within the context of this chronic disease. Such endeavors are deemed essential for advancing understanding and refining the clinical care of CF patients with G-I manifestations.

Development of the intestinal microbiome in cystic fibrosis in early life

Cystic fibrosis (CF) is a heritable disease that causes altered physiology at mucosal sites; these changes result in chronic infections in the lung, significant gastrointestinal complications as well as dysbiosis of the gut microbiome, although the latter has been less well explored. Here, we describe the longitudinal development of the gut microbiome in a cohort of children with CF (cwCF) from birth through early childhood (0-4 years of age) using 16S rRNA gene amplicon sequencing of stool samples as a surrogate for the gut microbiota. Similar to healthy populations, alpha diversity of the gut microbiome increases significantly with age, but diversity plateaus at ~2 years of age for this CF cohort. Several taxa that have been associated with dysbiosis in CF change with age toward a more healthy-like composition; notable exceptions include Akkermansia, which decreases with age, and Blautia, which increases with age. We also examined the relative abundance and prevalence of nine taxa associated with CF lung disease, several of which persist across early life, highlighting the possibility of the lung being seeded directly from the gut early in life. Finally, we applied the Crohn's Dysbiosis Index to each sample, and found that high Crohn's-associated dysbiosis early in life (<2 years) was associated with significantly lower Bacteroides in samples collected from 2 to 4 years of age. Together, these data comprise an observational study that describes the longitudinal development of the CF-associated gut microbiota and suggest that early markers associated with inflammatory bowel disease may shape the later gut microbiota of cwCF. IMPORTANCE Cystic fibrosis is a heritable disease that disrupts ion transport at mucosal surfaces, causing a buildup of mucus and dysregulation of microbial communities in both the lungs and the intestines. Persons with CF are known to have dysbiotic gut microbial communities, but the development of these communities over time beginning at birth has not been thoroughly studied. Here, we describe an observation study following the development of the gut microbiome of cwCF throughout the first 4 years of life, during the critical window of both gut microbiome and immune development. Our findings indicate the possibility of the gut microbiota as a reservoir of airway pathogens and a surprisingly early indication of a microbiota associated with inflammatory bowel disease.

Tezacaftor/Ivacaftor therapy has negligible effects on the cystic fibrosis gut microbiome

People with cystic fibrosis (pwCF) experience a range of persistent gastrointestinal symptoms throughout life. There is evidence indicating interaction between the microbiota and gut pathophysiology in CF. However, there is a paucity of knowledge on the potential effects of CF transmembrane conductance regulator (CFTR) modulator therapies on the gut microbiome. In a pilot study, we investigated the impact of Tezacaftor/Ivacaftor dual combination CFTR modulator therapy on the gut microbiota and metabolomic functioning in pwCF. Fecal samples from 12 pwCF taken at baseline and following placebo or Tezacaftor/Ivacaftor administration were subjected to microbiota sequencing and to targeted metabolomics to assess the short-chain fatty acid (SCFA) composition. Ten healthy matched controls were included as a comparison. Inflammatory calprotectin levels and patient symptoms were also investigated. No significant differences were observed in overall gut microbiota characteristics between any of the study stages, extended also across intestinal inflammation, gut symptoms, and SCFA-targeted metabolomics. However, microbiota and SCFA metabolomic compositions, in pwCF, were significantly different from controls in all study treatment stages. CFTR modulator therapy with Tezacaftor/Ivacaftor had negligible effects on both the gut microbiota and SCFA composition across the course of the study and did not alter toward compositions observed in healthy controls. Future longitudinal CFTR modulator studies will investigate more effective CFTR modulators and should use prolonged sampling periods, to determine whether longer-term changes occur in the CF gut microbiome. IMPORTANCE People with cystic fibrosis (pwCF) experience persistent gastrointestinal (GI) symptoms throughout life. The research question "how can we relieve gastrointestinal symptoms, such as stomach pain, bloating, and nausea?" remains a top priority for clinical research in CF. While CF transmembrane conductance regulator (CFTR) modulator therapies are understood to correct underlying issues of CF disease and increasing the numbers of pwCF are now receiving some form of CFTR modulator treatment. It is not known how these therapies affect the gut microbiome or GI system. In this pilot study, we investigated, for the first time, effects of the dual combination CFTR modulator medicine, Tezacaftor/Ivacaftor. We found it had negligible effects on patient GI symptoms, intestinal inflammation, or gut microbiome composition and functioning. Our findings are important as they fill important knowledge gaps on the relative effectiveness of these widely used treatments. We are now investigating triple combination CFTR modulators with prolonged sampling periods.

Can Bioactive Food Substances Contribute to Cystic Fibrosis-Related Cardiovascular Disease Prevention?

Advances in cystic fibrosis (CF) care have significantly improved the quality of life and life expectancy of patients. Nutritional therapy based on a high-calorie, high-fat diet, antibiotics, as well as new therapies focused on CFTR modulators change the natural course of the disease. They do so by improving pulmonary function and growing BMI. However, the increased weight of such patients can lead to unwanted long-term cardiovascular effects. People with CF (pwCF) experience several cardiovascular risk factors. Such factors include a high-fat diet and increased dietary intake, altered lipid metabolism, a decrease in the level of fat-soluble antioxidants, heightened systemic inflammation, therapeutic interventions, and diabetes mellitus. PwCF must pay special attention to food and eating habits in order to maintain a nutritional status that is as close as possible to the proper physiological one. They also have to benefit from appropriate nutritional counseling, which is essential in the evolution and prognosis of the disease. Growing evidence collected in the last years shows that many bioactive food components, such as phytochemicals, polyunsaturated fatty acids, and antioxidants have favorable effects in the management of CF. An important positive effect is cardiovascular prevention. The possibility of preventing/reducing cardiovascular risk in CF patients enhances both quality of life and life expectancy in the long run.

Cystic Fibrosis-Related Gut Dysbiosis: A Systematic Review

BACKGROUND AND AIMS

Cystic Fibrosis (CF) is associated with gut dysbiosis, local and systemic inflammation, and impaired immune function. Gut microbiota dysbiosis results from changes in the complex gut milieu in response to CF transmembrane conductance regulator (CFTR) dysfunction, pancreatic malabsorption, diet, medications, and environmental influences. In several diseases, alteration of the gut microbiota influences local and systemic inflammation and disease outcomes. We conducted a systematic review of the gut microbiota in CF and explored factors influencing dysbiosis.

METHODS

An electronic search of three databases was conducted in January 2019, and re-run in June 2021. Human, animal, and in vitro studies were included. The primary outcome was differences in the gut microbiota between people with CF (pwCF) and healthy controls. Secondary outcomes included the relationship between the gut microbiota and other factors, including diet, medication, inflammation, and pulmonary function in pwCF.

RESULTS

Thirty-eight studies were identified. The literature confirmed the presence of CF-related gut dysbiosis, characterized by reduced diversity and several taxonomic changes. There was a relative increase of bacteria associated with a pro-inflammatory response coupled with a reduction of those considered anti-inflammatory. However, studies linking gut dysbiosis to systemic and lung inflammation were limited. Causes of gut dysbiosis were multifactorial, and findings were variable. Data on the impact of CFTR modulators on the gut microbiota were limited.

CONCLUSIONS

CF-related gut dysbiosis is evident in pwCF. Whether this influences local and systemic disease and is amenable to interventions with diet and drugs, such as CFTR modulators, requires further investigation.

Gut Dysbiosis in Children with Cystic Fibrosis: Development, Features and the Role of Gut-Lung Axis on Disease Progression

Cystic fibrosis (CF) is the most common autosomal recessive disease among Caucasians. Over the last 20 years, culture-independent analysis, including next-generation sequencing, has paired with culture-based microbiology, offering deeper insight into CF lung and gut microbiota. The aim of this review is to analyse the features of gut microbiota in patients with CF and its possible role in the progression of the disease, establishing the basis for a potential role in microbe-based therapies. The literature analysis showed that the gut environment in CF patients has unique features due to the characteristics of the disease, such as decreased bicarbonate secretion, increased luminal viscosity, and an acidic small intestinal environment, which, due to the treatment, includes regular antibiotic use or a high-energy and fat-dense diet. As a result, the gut microbial composition appears altered, with reduced richness and diversity. Moreover, the population of pro-inflammatory bacteria is higher, while immunomodulatory genera, such as Bacteroides and Bifidobacterium, are scarcer. The imbalanced gut microbial population has a potential role in the development of systemic inflammation and may influence clinical outcomes, such as respiratory exacerbations, spirometry results, and overall growth. Although a better understanding of the pathophysiology behind the gut-lung axis is needed, these findings support the rationale for considering gut microbiota manipulation as a possible intervention to regulate the severity and progression of the disease.

Probiotics Administration in Cystic Fibrosis: What Is the Evidence?

In the last 20 years, gut microbiota in patients with cystic fibrosis (CF) has become an object of interest. It was shown that these patients had gut dysbiosis and this could explain not only the intestinal manifestations of the disease but also part of those involving the respiratory tract. The acquisition of previously unknown information about the importance of some bacteria, i.e., those partially or totally disappeared in the gut of CF patients, in the regulation of the activity and function of the gut and the lung was the base to suggest the use of probiotics in CF patients. The main aim of this paper is to discuss the biological basis for probiotic administration to CF patients and which results could be expected. Literature analysis showed that CF intestinal dysbiosis depends on the same genetic mutations that condition the clinical picture of the diseases and is aggravated by a series of therapeutic interventions, such as dietary modifications, the use of antibiotics, and the administration of antacids. All this translates into a significant worsening of the structure and function of organs, including the lung and intestine, already deeply penalized by the genetic alterations of CF. Probiotics can intervene on dysbiosis, reducing the negative effects derived from it. However, the available data cannot be considered sufficient to indicate that these bacteria are essential elements of CF therapy. Further studies that take into account the still unsolved aspects on how to use probiotics are absolutely necessary.

Changing paradigms in the treatment of gastrointestinal complications of cystic fibrosis in the era of cystic fibrosis transmembrane conductance regulator modulators

Cystic fibrosis (CF) - although primarily a lung disease - also causes a variety of gastrointestinal manifestations which are important for diagnosis, prognosis and quality of life. All parts of the gastrointestinal tract can be affected by CF. Besides the well-known pancreatic insufficiency, gastroesophageal reflux disease, liver disease and diseases of the large intestine are important pathologies that impact on prognosis and also impair quality of life. Diagnosis and management of gastrointestinal manifestations will be discussed in this review. Since optimisation of CF therapy is associated with a significantly longer life-span of CF patients nowadays, also gastrointestinal malignancies, which are more common in CF than in the non-CF population need to be considered. Furthermore, novel evidence on the role of the gut microbiome in CF is emerging. The introduction of cystic fibrosis transmembrane conductance regulator (CFTR) protein modulators gives hope for symptom alleviation and even cure of gastrointestinal manifestations of CF.

Intestinal Inflammation and Alterations in the Gut Microbiota in Cystic Fibrosis: A Review of the Current Evidence, Pathophysiology and Future Directions

Cystic fibrosis (CF) is a life-limiting autosomal recessive multisystem disease. While its burden of morbidity and mortality is classically associated with pulmonary disease, CF also profoundly affects the gastrointestinal (GI) tract. Chronic low-grade inflammation and alterations to the gut microbiota are hallmarks of the CF intestine. The etiology of these manifestations is likely multifactorial, resulting from cystic fibrosis transmembrane conductance regulator (CFTR) dysfunction, a high-fat CF diet, and the use of antibiotics. There may also be a bidirectional pathophysiological link between intestinal inflammation and changes to the gut microbiome. Additionally, a growing body of evidence suggests that these GI manifestations may have significant clinical associations with growth and nutrition, quality of life, and respiratory function in CF. As such, the potential utility of GI therapies and long-term GI outcomes are areas of interest in CF. Further research involving microbial modulation and multi-omics techniques may reveal novel insights. This article provides an overview of the current evidence, pathophysiology, and future research and therapeutic considerations pertaining to intestinal inflammation and alterations in the gut microbiota in CF.

What Do We Know about the Microbiome in Cystic Fibrosis? Is There a Role for Probiotics and Prebiotics?

Cystic fibrosis (CF) is a life-shortening genetic disorder that affects the cystic fibrosis transmembrane conductance regulator (CFTR) protein. In the gastrointestinal (GI) tract, CFTR dysfunction results in low intestinal pH, thick and inspissated mucus, a lack of endogenous pancreatic enzymes, and reduced motility. These mechanisms, combined with antibiotic therapies, drive GI inflammation and significant alteration of the GI microbiota (dysbiosis). Dysbiosis and inflammation are key factors in systemic inflammation and GI complications including malignancy. The following review examines the potential for probiotic and prebiotic therapies to provide clinical benefits through modulation of the microbiome. Evidence from randomised control trials suggest probiotics are likely to improve GI inflammation and reduce the incidence of CF pulmonary exacerbations. However, the highly variable, low-quality data is a barrier to the implementation of probiotics into routine CF care. Epidemiological studies and clinical trials support the potential of dietary fibre and prebiotic supplements to beneficially modulate the microbiome in gastrointestinal conditions. To date, limited evidence is available on their safety and efficacy in CF. Variable responses to probiotics and prebiotics highlight the need for personalised approaches that consider an individual's underlying microbiota, diet, and existing medications against the backdrop of the complex nutritional needs in CF.

Intestinal function and transit associate with gut microbiota dysbiosis in cystic fibrosis

BACKGROUND

Most people with cystic fibrosis (pwCF) suffer from gastrointestinal symptoms and are at risk of gut complications. Gut microbiota dysbiosis is apparent within the CF population across all age groups, with evidence linking dysbiosis to intestinal inflammation and other markers of health. This pilot study aimed to investigate the potential relationships between the gut microbiota and gastrointestinal physiology, transit, and health.

STUDY DESIGN

Faecal samples from 10 pwCF and matched controls were subject to 16S rRNA sequencing. Results were combined with clinical metadata and MRI metrics of gut function to investigate relationships.

RESULTS

pwCF had significantly reduced microbiota diversity compared to controls. Microbiota compositions were significantly different, suggesting remodelling of core and rarer satellite taxa in CF. Dissimilarity between groups was driven by a variety of taxa, including Escherichia coli, Bacteroides spp., Clostridium spp., and Faecalibacterium prausnitzii. The core taxa were explained primarily by CF disease, whilst the satellite taxa were associated with pulmonary antibiotic usage, CF disease, and gut function metrics. Species-specific ordination biplots revealed relationships between taxa and the clinical or MRI-based variables observed.

CONCLUSIONS

Alterations in gut function and transit resultant of CF disease are associated with the gut microbiota composition, notably the satellite taxa. Delayed transit in the small intestine might allow for the expansion of satellite taxa resulting in potential downstream consequences for core community function in the colon.

Year in review 2020: Nutrition and gastrointestinal disease in cystic fibrosis

The multisystemic manifestations of cystic fibrosis (CF) involve all parts of the gastrointestinal (GI) system, including the pancreas, intestine, and liver. As providers who care for people with CF, knowledge of the manifestations, treatment, and research related to nutrition and GI disease are important. This review is the last installment of the CF year in review 2020 series, focusing on nutritional, GI, and hepatobiliary articles from Pediatric Pulmonology and other journals of particular interest to clinicians.

The Gut-Lung Axis in Cystic Fibrosis

Cystic fibrosis (CF) is a heritable, multiorgan disease that impacts all tissues that normally express cystic fibrosis transmembrane conductance regulator (CFTR) protein. While the importance of the airway microbiota has long been recognized, the intestinal microbiota has only recently been recognized as an important player in both intestinal and lung health outcomes for persons with CF (pwCF). Here, we summarize current literature related to the gut-lung axis in CF, with a particular focus on three key ideas: (i) mechanisms through which microbes influence the gut-lung axis, (ii) drivers of microbiota alterations, and (iii) the potential for intestinal microbiota remediation.

Impact of Altered Gut Microbiota and Its Metabolites in Cystic Fibrosis

Cystic fibrosis (CF) is the most common lethal, multisystemic genetic disorder in Caucasians. Mutations in the gene encoding the cystic fibrosis transmembrane regulator (CFTR) protein are responsible for impairment of epithelial anionic transport, leading to impaired fluid regulation and pH imbalance across multiple organs. Gastrointestinal (GI) manifestations in CF may begin in utero and continue throughout the life, resulting in a chronic state of an altered intestinal milieu. Inherent dysfunction of CFTR leads to dysbiosis of the gut. This state of dysbiosis is further perpetuated by acquired factors such as use of antibiotics for recurrent pulmonary exacerbations. Since the gastrointestinal microbiome and their metabolites play a vital role in nutrition, metabolic, inflammatory, and immune functions, the gut dysbiosis will in turn impact various manifestations of CF-both GI and extra-GI. This review focuses on the consequences of gut dysbiosis and its metabolic implications on CF disease and possible ways to restore homeostasis.

PROMISE: Working with the CF community to understand emerging clinical and research needs for those treated with highly effective CFTR modulator therapy

Highly effective CFTR modulator drug therapy is increasingly available to those with cystic fibrosis. Multiple observational research studies are now being conducted to better understand the impacts of this important therapeutic milestone on long-term outcomes, patient care needs, and future research priorities. PROMISE is a large, multi-disciplinary academic study focused on the broad impacts of starting elexacaftor/tezacaftor/ivacaftor in the US population age 6 years and older. The many areas of investigation and rationale for each are discussed by organ systems, along with recognition of remaining important questions that will not be addressed by this study alone. Knowledge gained through this and multiple complementary studies around the world will help to understand important health outcomes, clinical care priorities, and research needs for a large majority of people treated with these or similarly effective medications targeting the primary cellular impairment in cystic fibrosis.

The Core of Gut Life: Firmicutes Profile in Patients with Relapsing-Remitting Multiple Sclerosis

The multiple sclerosis (MS) incidence rate has been increasing in Russia, but the information about the gut bacteriobiome in the MS-afflicted patients is scarce. Using the Illumina MiSeq sequencing of 16S rRNA gene amplicons, we aimed to analyze the Firmicutes phylum and its taxa in a cohort of Moscow patients with relapsing-remitting MS, assessing the effects of age, BMI, disease modifying therapy (DMT), disability (EDSS), and gender. Among 1252 identified bacterial OTUs, 857 represented Firmicutes. The phylum was the most abundant also in sequence reads, overall averaging 74 ± 13%. The general linear model (GLM) analysis implicated Firmicutes/Clostridia/Clostridiales/Lachospiraceae/Blautia/Blautia wexlerae as increasing with BMI, and only Lachospiraceae/Blautia/Blautia wexlerae as increasing with age. A marked DMT-related decrease in Firmicutes was observed in females at the phylum, class (Clostridia), and order (Clostridiales) levels. The results of our study implicate DMT and gender as factors shaping the fecal Firmicutes assemblages. Together with the gender-dependent differential MS incidence growth rate in the country, the results suggest the likely involvement of gender-specific pathoecological mechanisms underlying the occurrence of the disease, switching between its phenotypes and response to disease-modifying therapies. Overall, the presented profile of Firmicutes can be used as a reference for more detailed research aimed at elucidating the contribution of this core phylum and its lower taxa into the etiology and progression of relapsing-remitting multiple sclerosis.

Metabolomics profiling of tobacco exposure in children with cystic fibrosis

BACKGROUND

Inflammation is integral to early disease progression in children with CF. The effect of modifiable environmental factors on infection and inflammation in persons with CF is poorly understood. Our prior studies determined that secondhand smoke exposure (SHSe) is highly prevalent in young children with CF. SHSe is associated with increased inflammation, heightened bacterial burden, and worsened clinical outcomes. However, the specific metabolite and signaling pathways that regulate responses to SHSe in CF are relatively unknown.

METHODS

High-resolution metabolomics was performed on plasma samples from infants (n = 25) and children (n = 40) with CF compared to non-CF controls (n = 15). CF groups were stratified according to infant or child age and SHSe status.

RESULTS

Global metabolomic profiles segregated by age and SHSe status. SHSe in CF was associated with changes in pathways related to steroid biosynthesis, fatty acid metabolism, cysteine metabolism, and oxidative stress. CF infants with SHSe demonstrated enrichment for altered metabolite localization to the small intestine, liver, and striatum. CF children with SHSe demonstrated metabolite enrichment for organs/tissues associated with oxidative stress including mitochondria, peroxisomes, and the endoplasmic reticulum. In a confirmatory analysis, SHSe was associated with changes in biomarkers of oxidative stress and cellular adhesion including MMP-9, MPO, and ICAM-1.

CONCLUSIONS

SHSe in young children and infants with CF is associated with altered global metabolomics profiles and specific biochemical pathways, including enhanced oxidative stress. SHSe remains an important but understudied modifiable variable in early CF disease.