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OBJECTIVES: Tobacco smoke exposure reduces CFTR functional expression in vitro and contributes to acquired CFTR dysfunction. We investigated whether it also inhibits the clinical benefit of CFTR modulators, focusing on tezacaftor/ivacaftor, approved in February 2018 for individuals with CF age ≥12 years. METHODS: A retrospective longitudinal analysis of encounter-based data from the CF Foundation Patient Registry (2016-2018) compared the slope of change in lung function (GLI FEV(1)% predicted) before and after tezacaftor/ivacaftor initiation in smoke-exposed vs unexposed age-eligible pediatric patients. Tobacco smoke exposure (Ever/Never) was determined from caregiver self-report. Statistical analyses used hierarchical linear mixed modeling and fixed effects regression modeling. RESULTS: The sample included 6,653 individuals with a total of 105,539 person-period observations. Tezacaftor/ivacaftor was prescribed to 19% (1,251) of individuals, mean age 17 years, mean baseline ppFEV(1) 83%, 28% smoke-exposed. Tezacaftor/ivacaftor users who were smoke-exposed had a lower baseline ppFEV(1) and experienced a greater lung function decline. Over two years, the difference in ppFEV(1) by smoke exposure among tezacaftor/ivacaftor users increased by 1.2% (7.6% to 8.8%, p

Background: Few studies have attempted to disentangle the effects of tobacco smoke exposure and socioeconomic factors on lung function decline in pediatric CF. The current study evaluates their contributions longitudinally across the entire U.S. CF care network population. Methods: Data from the CF Foundation Patient Registry were obtained on all individuals who at the end of 2016 were 6-18 years old. Lung function measures (median, highest, and lowest ppFEV1) for each person were calculated at each attained age. Multivariable analyses used mixed modeling to assess the impact of smoke exposure and socioeconomic factors on both initial lung function and change over time. Findings: The sample included 10,692 individuals contributing 57,888 person years. At age 6, ppFEV1 of smoke-exposed children was 4% lower than among unexposed. The deficit persisted through age 18. In fully adjusted mixed models, smoke exposure and socioeconomic factors had independent, additive associations with lung function. Median ppFEV1 declined 2% with smoke exposure, 3% with lower paternal education, 1% with public insurance, and increased 0.2% with each $10,000 annual household income. The effect of smoke exposure on ppFEV1 was larger in disadvantaged children compared to privileged counterparts (2.5% vs 1.5%). Interpretation: Smoke exposure and socioeconomic factors are independent risk factors for decreased ppFEV1 in pediatric CF. Strategies to reduce smoke exposure should be introduced early. Interventions may be prioritized in disadvantaged children, among whom the exposure has a disproportionately large effect. Funding Statement: This study was supported by grants from NIH (P30DK72482, K08HL140190), AHRQ (K12HS023009), and CFF (CC032-14). Declaration of Interests: The authors have no conflicts of interest. Ethics Approval Statement: Written informed consent was obtained from all participants. The study was approved by the Institutional Review Board of the University of Alabama at Birmingham (protocol number 300002076).

Objective Tobacco smoke exposure has negative impacts on the lung health of children with cystic fibrosis (CF), yet evidence-based strategies for smoking cessation have not been tested with or tailored to CF caregivers. This qualitative study identified barriers and facilitators of smoking cessation in this population and outlined potential interventional approaches. Methods We conducted semi-structured interviews with CF familial caregivers who were current or former smokers, and with members of the CF care team. We asked about experiences, practices, and prerequisites for a successful program. Interviews were recorded, transcribed verbatim, and coded by two investigators. Analysis used a thematic approach guided by the PRECEDE model, which identifies predisposing (intrapersonal), reinforcing (interpersonal), and enabling (structural) factors relevant to health behaviors and programs. Results Seventeen interviews were conducted-eight with familial caregivers and nine with CF team members. Whereas caregivers provided greater insight into internal difficulties and motivators to quit smoking, clinicians offered more extensive input on barriers and solutions related to the clinical environment. Based on study recommendations, a successful tobacco cessation program should include (a) family education about the harms of smoke exposure for children with CF; (b) screening for exposure, ideally with biochemical verification; (c) access to trained tobacco counselors; (d) affordable pharmacotherapy; and (e) outpatient follow-up of those undergoing tobacco treatment. Conclusion This qualitative study revealed intrapersonal, interpersonal, and structural barriers to eliminating tobacco smoke exposure in children with CF, outlined opportunities to address these barriers, and made recommendations for a comprehensive tobacco cessation strategy.

The best strategy to manage an interarytenoid defect [Type 1 laryngeal cleft (LC-1) or deep interarytenoid groove (DIG)] in pediatric aerodigestive patients with dysphagia remains uncertain. This study compared benefit of interarytenoid augmentation (IAA) to suture repair or clinical observation alone in pediatric patients.A 3-year retrospective, single-center analysis of children with dysphagia undergoing endoscopic airway evaluation was performed. Physician preference guided treatment plan: suture repair with CO2 laser, IAA (carboxy methylcellulose or calcium hydroxyapatite), or observation. Primary outcome was improved post-operative diet. Significance was assumed at p 0.05.449 patients underwent diagnostic endoscopy. Mean age (±SD) at procedure was 21 ± 13 months, with nearly one fourth (28 %) of children ≤ 12 months. Eighty (18 %) had either an LC-1 (n = 55) or DIG (n = 25). Of these, 35 (42 %) underwent suture repair, 22 (28 %) IAA, and 23 (30 %) observation only. Aspiration improved overall in the interventional groups compared to observational controls (58 % vs. 9 %, p 0.05), with no change in benefit observed by age of intervention. IAA was as effective as suture repair (59 % vs 55 %, p = 0.46). In patients with only a DIG, IAA intervention alone significantly improved swallow function (66.6 % vs. 0 %, p 0.05).In pediatric aerodigestive patients with dysphagia, 18 % of children have an addressable lesion. IAA or suture repair similarly improves dietary advancement. IAA improves swallow function in patients with DIG. These findings support a novel protocol to intervene in dysphagia patients with LC-1 or DIG via IAA at the initial operative evaluation.

BACKGROUND: In US cystic fibrosis (CF) patients, methicillin-resistant Staphylococcus aureus (MRSA) rates have tripled in the past 2 decades. Known clinical risk factors include exposure to a healthcare setting, Pseudomonas aeruginosa and CF-related diabetes. Area-level socio-environmental exposures have not been evaluated. We explored the association of area-level deprivation with MRSA prevalence in a pediatric CF Center in the Southeastern United States. METHODS: Patients’ residential addresses were geocoded and linked to a composite Area Deprivation Index and Rural-Urban Commuting Area scores. The association of MRSA with Area Deprivation Index and Rural-Urban Commuting Area scores was evaluated using logistic regression with robust standard errors adjusted for sociodemographic covariates (age, sex, race, mother’s and father’s education and household income), clinical risk factors (P. aeruginosa, CF-related diabetes, hospitalizations and number of clinic visits) and clustering. RESULTS: The study included all pediatric patients (N = 231; mean age 12) at a single CF Center. MRSA was present in 44% of subjects. Higher area-level deprivation was correlated with rural residence, lack of parental college education and lower household income (P < 0.001 for each). In a multiple regression model fully adjusted for patient-level sociodemographic covariates, clinical risk factors and clustering, neighborhood deprivation was associated with more than 2-fold increase in the odds of having MRSA [OR 2.26 (1.14–4.45), P < 0.05]. CONCLUSIONS: Neighborhood deprivation is a risk factor for MRSA in pediatric CF, doubling the odds of infection. Community-level socioeconomic risk factors should be considered when developing prevention strategies and treatment plans for MRSA infection in pediatric patients with CF.

Tobacco smoke exposure is a major risk factor for the health of children and adolescents with CF. In this study, we assess whether cessation of smoke exposure is associated with improved outcomes in this population.We used annualized and encounter-based data from the U.S. CF Foundation Patient Registry (2006-2018) on all individuals born 1998-2010. The analytical sample included those who ever reported second-hand smoke exposure (daily or weekly), ever lived with a smoker, or ever reported smoking themselves. We used non-linear mixed models for pulmonary exacerbations and linear mixed models for ppFEVThe sample included 3,633 individuals contributing 19,629 person-years. Cessation of smoke exposure reduced the odds of a pulmonary exacerbation in 12 months by 17% (OR 0.83, p 0.001) in the first year of cessation, with an additional 6% decrease (OR 0.94, p = 0.003) for each additional year of cessation. Cessation was associated with improvements in ppFEVEliminating smoke exposure may reduce pulmonary exacerbations and improve respiratory and nutritional outcomes in children and adolescents with CF. Both smoking cessation and exposure prevention should be prioritized in pediatric CF care.

Rationale: MicroRNAs (miRNAs) destabilize mRNA transcripts and inhibit protein translation. miR-145 is of particular interest in cystic fibrosis (CF) as it has a direct binding site in the 3′-untranslated region of CFTR (cystic fibrosis transmembrane conductance regulator) and is upregulated by the CF genetic modifier TGF (transforming growth factor)-β. Objectives: To demonstrate that miR-145 mediates TGF-β inhibition of CFTR synthesis and function in airway epithelia. Methods: Primary human CF (F508del homozygous) and non-CF airway epithelial cells were grown to terminal differentiation at the air–liquid interface on permeable supports. TGF-β (5 ng/ml), a miR-145 mimic (20 nM), and a miR-145 antagonist (20 nM) were used to manipulate CFTR function. In CF cells, lumacaftor (3 μM) and ivacaftor (10 μM) corrected mutant F508del CFTR. Quantification of CFTR mRNA, protein, and function was done by standard techniques. Measurements and Main Results: miR-145 is increased fourfold in CF BAL fluid compared with non-CF (P

Epidemiologic studies have linked gestational vitamin D deficiency to respiratory diseases, although mechanisms have not been defined. We hypothesized that antenatal vitamin D deficiency would impair airway development and alveolarization in a mouse model. We studied the effect of antenatal vitamin D deficiency by inducing it in pregnant mice and then compared lung development and function in their offspring to littermate controls. Postnatal vitamin D deficiency and sufficiency models from each group were also studied. We developed a novel tracheal ultrasound imaging technique to measure tracheal diameter in vivo. Histological analysis estimated tracheal cartilage total area and thickness. We found that vitamin D-deficient pups had reduced tracheal diameter with decreased tracheal cartilage minimal width. Vitamin D deficiency increased airway resistance and reduced lung compliance, and led to alveolar simplification. Postnatal vitamin D supplementation improved lung function and radial alveolar count, a parameter of alveolar development, but did not correct tracheal narrowing. We conclude that antenatal vitamin D deficiency impairs airway and alveolar development and limits lung function. Reduced tracheal diameter, cartilage irregularity, and alveolar simplification in vitamin D-deficient mice may contribute to increased airways resistance and diminished lung compliance. Vitamin D supplementation after birth improved lung function and, potentially, alveolar simplification, but did not improve defective tracheal structure. This mouse model offers insight into the mechanisms of vitamin D deficiency-associated lung disease and provides an in vivo model for investigating preclinical preventive and therapeutic strategies.

Pulmonary complications post hematopoietic stem cell transplant in dyskeratosis congenita: analysis of oxidative stress in lung fibroblasts

Myeloid cell receptor tyrosine kinases TYRO3, AXL, and MERTK and their ligands, GAS6 and PROTEIN S, physiologically suppress innate immune responses, including in the tumor microenvironment. Here, we showed that myeloid-derived suppressor cells (MDSC) dramatically upregulated TYRO3, AXL, and MERTK and their ligands [monocytic MDSCs (M-MDSC)>20-fold, polymorphonuclear MDSCs (PMN-MDSC)>15-fold] in tumor-bearing mice. MDSCs from tumor-bearing Mertk−/−, Axl−/−, and Tyro3−/− mice exhibited diminished suppressive enzymatic capabilities, displayed deficits in T-cell suppression, and migrated poorly to tumor-draining lymph nodes. In coimplantation experiments using TYRO3−/−, AXL−/−, and MERTK−/− MDSCs, we showed the absence of these RTKs reversed the protumorigenic properties of MDSCs in vivo. Consistent with these findings, in vivo pharmacologic TYRO3, AXL, and MERTK inhibition diminished MDSC suppressive capability, slowed tumor growth, increased CD8+ T-cell infiltration, and augmented anti–PD-1 checkpoint inhibitor immunotherapy. Mechanistically, MERTK regulated MDSC suppression and differentiation in part through regulation of STAT3 serine phosphorylation and nuclear localization. Analysis of metastatic melanoma patients demonstrated an enrichment of circulating MERTK+ and TYRO3+ M-MDSCs, PMN-MDSCs, and early-stage MDSCs (e-MDSC) relative to these MDSC populations in healthy controls. These studies demonstrated that TYRO3, AXL, and MERTK control MDSC functionality and serve as promising pharmacologic targets for regulating MDSC-mediated immune suppression in cancer patients.

BACKGROUND: Historically, studies of adherence to airway clearance therapy in cystic fibrosis (CF) have relied on self-reporting. We compared self-reported airway clearance therapy adherence to actual usage data from home high-frequency chest wall compressions (HFCWC) vests and identified factors associated with overestimation of adherence in self-reports. METHODS: Pediatric patients who perform airway clearance therapy with a HFCWC vest were eligible to participate. Objective adherence data were obtained from the HFCWC device, which records cumulative utilization time. Two readings at least 5 weeks apart were collected. Objective adherence was recorded as a ratio of mean-to-prescribed daily use (%). Self-reported adherence data were collected with a caregiver survey at enrollment. Adherence rates were categorized as low (< 35% of prescribed), moderate (36–79% of prescribed), and high (≥ 80% of prescribed). An overestimation was present when self-reported adherence was at least one category higher than objective adherence. RESULTS: In the final sample (N = 110), mean adherence by usage data was 61%. Only 35% of subjects (n = 38) were highly adherent, and 28% (n = 31) were low adherent. In contrast, 65% of subjects (n = 72) reported high adherence and only 8% (n = 9) reported low adherence (P < .001). Nearly half of self-reports (46%) overestimated adherence. In a multiple regression analysis, overestimation was associated with multiple airway clearance therapy locations (odds ratio 7.13, 95% CI 1.16–43.72, P = .034) and prescribed daily use ≥ 60 min (odds ratio 3.85, 95% CI 1.08–13.76, P < .038). Among subjects with prescribed daily airway clearance therapy ≥ 60 min, the odds of overestimating adherence increased 3-fold (odds ratio 3.04, 95% CI 1.17–7.87, P = .02) in a lower-income (< $50,000/y) environment. CONCLUSIONS: Self-reports overestimated actual adherence to airway clearance therapy, and the overestimation increased with treatment occurring in multiple households and prescribed therapy duration. Among participants with prescribed airway clearance therapy ≥ 60 min, overestimation increased with lower income. Objective measures of adherence are needed, particularly for lower-income children and those receiving treatments in multiple locations.

SummaryObjective The clinical benefit of newborn screening (NBS) for cystic fibrosis (CF) has been primarily nutritional, with less overt respiratory impact. Identification of risk factors for infant CF lung disease could facilitate targeted interventions to improve pulmonary outcomes. Methods This retrospective study evaluated socioeconomic information, clinical data, and results from routine infant pulmonary function testing (iPFT) of infants diagnosed with CF through NBS (N = 43) at a single CF center over a 4-year period (2008–2012). A five-item composite clinical score was developed and combined with socioeconomic indicators to facilitate identification of CF infants at increased risk of early-onset respiratory impairment. Results Paternal education was positively associated with lung function (P = 0.02). Clinical score

Background Ivacaftor improves clinical outcome by potentiation of mutant G551D CFTR. Due to the presence of CFTR in monocytes and polymorphonuclear neutrophils (PMNs), we hypothesized that ivacaftor may impact leukocyte activation. Methods We examined blood leukocytes from G551D CF subjects prior to and at one and six months after receiving ivacaftor. Blood leukocytes from ivacaftor-naive G551D, F508del, and healthy controls were also treated with ivacaftor ex vivo to assess mutation-specific effects. Results Compared to healthy controls, G551D CF subjects had significantly higher expression of active CD11b on PMNs and of CD63 on monocytes, which were normalized by in vivo ivacaftor treatment. Ex vivo exposure to ivacaftor of blood cells from G551D, but not F508del and healthy subjects, resulted in changes in CXCR2 and CD16 expression on PMNs. Conclusions In vivo and ex vivo exposure of G551D CF leukocytes to ivacaftor resulted in an altered activation profile, suggesting mutation-specific leukocyte modulation.

Objectives The evidence linking socioeconomic status (SES) and adherence in cystic fibrosis (CF) is inconclusive and focused on medication uptake. We examined associations between SES, adherence to airway clearance therapy (ACT), and CF respiratory outcomes.

Aminoglycoside (AG) therapy is a common cause of acute kidney injury (AKI) in cystic fibrosis (CF) patients. The aim of this study was to identify factors associated with AKI during intravenous AG courses in this population. This was a matched case–control study utilizing two independent cohorts of hospitalized CF patients receiving ≥3 days of intravenous AG at Cincinnati Children’s Hospital Medical Center and Children’s of Alabama. All admissions with AKI (cases, N = 82) were matched to two randomly selected admissions without AKI (controls, N = 164) by center, gender, and age ±3 years of the case. AKI was defined as a 1.5-fold increase in the baseline serum creatinine (SCr) level or by an increase in SCr level of 0.3 mg/dL within 48 h. Admissions with AKI before day 4 or without at least weekly SCr monitoring were excluded from the analysis. Factors were compared between cases and controls using simple and multiple conditional logistic regression. Multivariable analysis identified receipt of an AG within 90 days prior to admission, longer duration of AG therapy, low serum albumin, and receipt of trimethoprim/sulfamethoxazole as independent risk factors for developing AKI. Infection with Staphylococcus aureus diminished the odds of developing AKI. This study identifies risk factors contributing to AG-associated AKI in CF patients. These findings can be used to anticipate high-risk scenarios and limit AKI in CF patients under clinical care.

Our objectives were to characterise the microbiota in cystic fibrosis (CF) bronchoalveolar lavage fluid (BALF), and determine its relationship to inflammation and disease status.BALF from paediatric and adult CF patients and paediatric disease controls undergoing clinically indicated bronchoscopy was analysed for total bacterial load and for microbiota by 16S rDNA sequencing.We examined 191 BALF samples (146 CF and 45 disease controls) from 13 CF centres. In CF patients aged e.g. Streptococcus, Prevotella and Veillonella) constituted ∼50% of the microbiota, whereas in CF patients aged ≥6 years, traditional CF taxa (e.g. Pseudomonas, Staphylococcus and Stenotrophomonas) predominated. Sequencing detected a dominant taxon not traditionally associated with CF (e.g. Streptococcus or Prevotella) in 20% of CF BALF and identified bacteria in 24% of culture-negative BALF. Microbial diversity and relative abundance of Streptococcus, Prevotella and Veillonella were inversely associated with airway inflammation. Microbiota communities were distinct in CF compared with disease controls, but did not differ based on pulmonary exacerbation status in CF.The CF microbiota detected in BALF differs with age. In CF patients aged Streptococcus predominates, whereas classic CF pathogens predominate in most older children and adults.

Background There are no population-based surveillance systems to determine prevalence, impact or outcomes in sickle cell disease (SCD). Estimates of the SCD population in California range broadly from 4,500 to 7,000, and little is known about their health status, health care utilization or health outcomes. A surveillance strategy was implemented using diverse data sources to develop a multi-dimensional, state-based surveillance system for SCD that includes adults and children and describes utilization, treatment and outcomes. Procedure Data from California newborn screening, inpatient and emergency room records, Medi-Cal/Medicaid claims and two SCD special care centers were collected for 2004-2008. A multi-step, iterative linkage process was used to link and de-duplicate these data sources, and case definitions were used to categorize cases. Results After linking and de-duplicating, there were 1,975 confirmed cases of SCD, 3,159 probable cases as well as 8,024 possible cases. Among individual data sources, newborn screening and data from clinics contributed the greatest number of unique cases to the total. Select analyses of utilization and treatments for the population are described. Conclusions Using linked existing data sources, an estimate of the statewide count of the SCD population is possible. The approach can be used to create an in-depth health status profile of the affected population by aggregating utilization, treatment, and outcomes data including mortality and morbidity information. This effort sets the stage for development of an on-going, state-based surveillance system.

Refractory lung function decline in association with recurrent pulmonary exacerbations is a common, yet poorly explained finding in cystic fibrosis (CF). To investigate the histopathologic mechanisms of pulmonary deterioration during adolescence and early adulthood, we reviewed clinically-indicated lung biopsy specimens obtained during a period of persistent decline.To determine if peribronchiolar remodeling is prominent in lung biopsy specimens obtained in adolescents with CF refractory to conventional therapy.Six adolescents with CF (mean age, 16.2 y; mean FEVAll computed tomography scans demonstrated a mix of bronchiectasis and hyperinflation that was variable across lung regions and within patients. Lung biopsy revealed significant peribronchiolar remodeling, particularly in patients with more advanced disease, with near complete obliteration of the peribronchiolar lumen (constrictive bronchiolitis). Myofibroblast differentiation (a TGF-β-dependent process) was prominent in specimens with significant airway remodeling.Constrictive bronchiolitis is widely present in the lung tissue of adolescents with CF with advanced disease and may contribute to impaired lung function that is refractory to conventional therapy (antibiotics, antiinflammatories, and mucolytics). TGF-β-dependent myofibroblast differentiation is prominent in areas of active fibrogenesis and may foster small airway remodeling in CF lung disease.

Endoglin (ENG) regulates signaling by transforming growth factor‐β (TGF‐β), a genetic modifier of cystic fibrosis (CF) lung disease severity. We hypothesized that ENG mediates TGF‐β pathobiology in CF airway epithelia. Comparing CF and non‐CF human lungs, we measured ENG by qPCR, immunoblotting and ELISA. In human bronchial epithelial cell lines (16HBE), we used CFTR siRNA knockdown and functional inhibition (CFTRINH‐172) to connect loss of CFTR to ENG synthesis. Plasmid overexpression of ENG assessed the direct effect of ENG on TGF‐β transcription and signal amplification in 16HBE cells. We found ENG protein to be increased more than fivefold both in human CF bronchoalveolar fluid (BALF) and human CF lung homogenates. ENG transcripts were increased threefold in CF, with a twofold increase in TGF‐β signaling. CFTR knockdown in 16HBE cells tripled ENG transcription and doubled protein levels with corresponding increases in TGF‐β signaling. Plasmid overexpression of ENG alone nearly doubled TGF‐β1 mRNA and increased TGF‐β signaling in 16HBE cells. These experiments identify that loss of CFTR function increases ENG expression in CF epithelia and amplifies TGF‐β signaling. Targeting ENG may offer a novel therapeutic opportunity to address TGF‐β associated pathobiology in CF.

The clinical benefit of newborn screening (NBS) for cystic fibrosis (CF) has been primarily nutritional, with less overt respiratory impact. Identification of risk factors for infant CF lung disease could facilitate targeted interventions to improve pulmonary outcomes.This retrospective study evaluated socioeconomic information, clinical data, and results from routine infant pulmonary function testing (iPFT) of infants diagnosed with CF through NBS (N = 43) at a single CF center over a 4-year period (2008-2012). A five-item composite clinical score was developed and combined with socioeconomic indicators to facilitate identification of CF infants at increased risk of early-onset respiratory impairment.Paternal education was positively associated with lung function (P = 0.02). Clinical score7 (on a scale of 0-10) predicted diminished pulmonary measure (P 0.005). Retrospective risk stratification by clinical score and paternal education identified CF infants at low, intermediate, or high risk of pulmonary disease. Forced expiratory volume (FEVWe combined socioeconomic and clinical data to risk-stratify CF infants for early-onset lung disease as quantified by iPFT. Our model showed significant differences in infant pulmonary function across risk groups. The developed tool offers an easily available, inexpensive, and non-invasive way to assess risk of respiratory decline in CF infants and identify those meriting targeted therapeutic attention. Pediatr Pulmonol. 2016;51:1168-1176. © 2016 Wiley Periodicals, Inc.

The cystic fibrosis transmembrane conductance regulator (CFTR) is an essential anion channel that regulates fluid and electrolyte transport across a variety of epithelia. Mutations that reduce CFTR protein expression or channel activity cause cystic fibrosis, the most common lethal recessive genetic disorder among Caucasians. CFTR occupies a prominent position among ion channels, as physiologic investigation of genotype/phenotype correlation has led to significant biomedical advancement with direct consequence on quality of life and survival. Here, we review our current understanding of how CFTR functions as an ATP-gated and phosphorylation-regulated anion channel that is the only identified ion channel in the large superfamily of ATP-binding cassette (ABC) transporters. The CFTR gating mechanism is also compared to the gating mechanisms of other more conventional ligand-gated channels with an interpretation of how prospective drugs may affect channel function. The various mechanisms by which different classes of CFTR mutations disrupt the function of this anion channel to cause cystic fibrosis are also discussed. Finally, we review the clinical manifestations of cystic fibrosis disease and current treatment options with an emphasis on the recent development of drugs that directly target the basic anion channel defect.

Introduction Transforming growth factor beta-1 (TGF-β1) is an important genetic modifier of lung disease severity in cystic fibrosis (CF), yet the mechanism behind this disease association remains unknown. Initial steps in the investigation of the relationship between TGF-β1 and CF lung disease include determining the most appropriate available biospecimen for TGF-β1 protein measurement.

OBJECTIVES/SPECIFIC AIMS: CFTR is the mutant protein that causes cystic fibrosis (CF), a fatal respiratory diseases affecting 1 in 3500 children. CFTR modulators are small molecules that directly address mutant CFTR function. Improving correction of the F508del CFTR mutation (affecting 90% of CF patients) is one of the most pressing unmet needs in CF. Currently available F508del therapeutics only marginally improve CF, In vitro, we have identified a miRNA that impairs utility of CFTR directed therapies. miR-145 is upregulated by TGF-β (a genetic modifier of CF lung disease) with a direct binding site on the 3’-untranslated region of CFTR mRNA. Binding of miR-145 to CFTR destabilizes mRNA transcript and impedes protein translation. Overexpression of miR-145 abolishes benefit of F508del CFTR correction. Antagonists to miR-145 block TGF-β suppression of CFTR function and augment response to CFTR correction. This project evaluate in vivo impact of TGF-beta and miRNA manipulation on CFTR functional readouts including nasal potential difference (NPD) and short circuit current (Isc) across tracheal explants in addition to standard biochemical measures. METHODS/STUDY POPULATION: Wild-type Sprague-Dawley rats were inoculated with an adenoviral vector containing bioactive TGF-beta or sham at 1×109 pfu/animal placed in the left nares. Seven days post-inoculation, functional, and biochemical measures were conducted. NPD was measured with a microelectrode placed in the left nare and grounded the tail. The nare was sequentially perfused with standard Ringer’s solution, amiloride (to block the ENaC sodium channel), low chloride Ringer’s (to stimulate chloride efflux), forskolin (to open the CFTR channel) and CFTRinh-172 (to block the CFTR channel. Tracheal explants were harvested, microdissected, and placed on modified Ussing chambers. RESULTS/ANTICIPATED RESULTS: We have inoculated WT rats with bioactive TGF-β Versus sham delivered by intranasal inoculation of an adenoviral vector. Functional readout of CFTR function is by Isc across tracheal epithelia and NPD. Lung homogenates are analyzed for TGF-β signaling, miRNA expression, and CFTR transcripts. Both tracheal explants and NPD indicate TGF-β stimulation diminishes CFTR function in vivo. In tracheal explants, TGF-β exposure diminishes CFTR response to forskolin-stimulation by 75%. Loss of current after CFTR inhibition (CFTRinh-172) is halved. By nasal PD, TGF-β inoculation similarly halves the bioelectric response to low chloride and forskolin stimulation. Evaluation by qPCR reveals a strong increase in TGF-β signaling demarcated by PAI-1, prompting a reduction in CFTR mRNA. miR-145 is expressed highly in rat pulmonary tissue, but no change in overall miR-145 levels was detected between TGF-β and sham exposed rats. This finding reflects what we have observed in human lungs, with a localized increased miR-145 expression in CF epithelia, but similarly high levels of miR-145 in both CF and non-CF whole lung homogenates. Although expressed at lower levels than miR-145, we did find increased expression in TGF-β relevant miR-101, miR-494, and miR-144 that have a predicted binding site on rat 3’-UTR in TGF-β exposed Versus sham lungs. DISCUSSION/SIGNIFICANCE OF IMPACT: Our data indicate the relevance of TGF-β stimulation to suppress CFTR synthesis and function in vivo. Future work will evaluate whether these additional miRNA with CFTR binding sites may mediate TGF-β suppression of CFTR in the rat model, and the utility of miRNA manipulation to augment F508del CFTR correction.

Rationale Inhaled tobramycin has been shown to transiently clear Pseudomonas from lower airways in early cystic fibrosis (CF), but does not markedly reduce lung inflammation, a key factor in disease progression. Objective Test the hypothesis that systemic antibiotics are more effective than inhaled antibiotics for reducing lower airways inflammation. Methods Clinically stable CF children with recent Pseudomonas were randomized to receive 4 weeks of inhaled tobramycin or 2 weeks of systemic antibiotics (intravenous ceftazidime and tobramycin). Bronchoalveolar lavage fluid was obtained just before and 4–6 weeks after treatment. The primary outcome was change in % neutrophils in lavage fluid. Results Fifteen subjects (inhaled = 6, systemic = 9) completed the protocol. Three Systemic Group subjects could not have central venous access established and were treated with oral ciprofloxacin (plus inhaled tobramycin) for 2 weeks as an alternative “systemic” regimen, per protocol. Groups were well matched in age, markers of disease severity, and initial % neutrophils. The Systemic Group showed a modest median change in percent neutrophils (−7%) which was not statistically significant compared to inhaled (+5.4%, P = 0.07). However, the Systemic Group had significantly greater reductions in total cells (−50% vs. −3%, P

Rationale Transforming factor β1 (TGF-β1) genetic polymorphisms have been identified as a modifier of cystic fibrosis (CF) lung disease severity. However, few data link TGF-β1 protein levels and clinical markers of CF lung disease severity. Objectives To determine the association between protein levels of TGF-β1 in pediatric CF bronchoalveolar lavage fluid (BALF) and clinical parameters of CF lung disease severity. Methods Total TGF-β1 was measured in BALF from 30 pediatric CF patients and 12 non-CF disease controls undergoing clinically indicated flexible bronchoscopy, and compared to four indicators of clinical disease: infection, inflammation, pulmonary function, and recent/recurrent hospitalization. Results TGF-β1 was elevated in CF BALF compared to non-CF controls (135 ± 15 pg/ml vs. 57 ± 10 pg/ml, P

Summary. Background: The relationship between lower airway markers of inflammation and infection with physiologic findings is poorly understood in young children with cystic fibrosis (CF). The goal of this study was to evaluate the association of bronchoalveolar lavage fluid (BALF) markers of infection and inflammation, including mediators linked to airway remodeling, to infant lung function values in young children with CF undergoing clinically indicated bronchoscopy. Methods: Plethysmography and the raised volume rapid thoracoabdominal compression (RVRTC) technique were performed in 16 sedated infants and young children with CF prior to bronchoscopy. BALF was collected and analyzed for pathogen density, cell count, % neutrophils, transforming growth factor beta 1 (TGF-b1), matrix metalloproteinases (MMP), and interleukin-8 (IL-8). Results: There was a significant direct correlation between functional residual capacity (FRC), the ratio of residual volume to total lung capacity (RV/TLC) and FRC/TLC with % neutrophils (P < 0.05). Forced expiratory flows were inversely correlated to % neutrophils (P < 0.01). Lung function parameters did not differentiate those with and without lower airway infection; however, pathogen density directly correlated with FRC and inversely correlated with flows (P < 0.05). In a subset of the population, MMP-2 directly correlated with RV/TLC and inversely correlated with flows (P < 0.05) and TGF-b1 directly correlated with FRC (P < 0.05). Conclusions: Results from this study suggest that lower airway inflammation as well as mediators linked to airway remodeling play an active role in pulmonary deterioration in CF infants and young children undergoing clinically indicated bronchoscopy. Pediatr Pulmonol. 2009; 44:503–511.

Ivacaftor has been shown to be a safe, effective treatment for cystic fibrosis in patients aged 6 years or older with a CFTR gating mutation. We aimed to assess the safety, pharmacokinetics, and pharmacodynamics of ivacaftor in children aged 2-5 years.In the two-part KIWI study, we enrolled children aged 2-5 years weighing 8 kg or more with a confirmed diagnosis of cystic fibrosis and a CFTR gating mutation on at least one allele from 15 hospitals in the USA, UK, and Canada. Participants received oral ivacaftor 50 mg (if bodyweight14 kg) or 75 mg (if bodyweight ≥14 kg) every 12 h for 4 days in part A (to establish the short-term safety of doses for subsequent assessment in part B), and then for 24 weeks in part B (to assess safety and longer-term pharmacodynamics). Children could participate in both or just one part of the study. Primary outcomes were pharmacokinetics and safety, analysed in all patients who received at least one dose of ivacaftor. Secondary outcomes were absolute change from baseline in sweat chloride concentrations and bodyweight, body-mass index (BMI), and height Z scores, and pharmacokinetic parameter estimation of ivacaftor. This study is registered with ClinicalTrials.gov, number NCT01705145.Between Jan 8, 2013, and March 1, 2013, nine patients were enrolled onto part A of the study, all of whom completed the 4 day treatment period, and eight of whom took part in part B. Between June 28, 2013, and Sept 26, 2013, 34 patients were enrolled in part B, 33 of whom completed the 24 week treatment period. All patients received at least one dose of ivacaftor. Results of ivacaftor pharmacokinetics suggested that exposure was similar to that reported in adults (median Cmin were 536 ng/mL for the 50 mg dose; 580 ng/mL for the 75 mg dose; median ivacaftor AUC values were 9840 ng × h/mL and 10 200 ng × h/mL, respectively). Common adverse events in part B included cough (in 19 [56%] of 34 patients) and vomiting (in ten [29%]). Five (15%) patients had liver function test (LFT) results that were more than eight times higher than the upper limit of normal, four of whom had study drug interrupted, and one of whom had study drug discontinued. Six (18%) of 34 patients had seven serious adverse events; a raised concentration of transaminases was the only serious adverse event regarded as related to ivacaftor and the only adverse event that resulted in study treatment discontinuation. At week 24, in patients for whom we had data, sweat chloride had changed from baseline by a mean of -46·9 mmol/L (SD 26·2, p0·0001), weight Z score by 0·2 (0·3; p0·0001), BMI Z score by 0·4 (0·4, p0·0001), and height Z score by -0·01 (0·3; p=0·84).Ivacaftor at doses of 50 mg and 75 mg seems to be safe in children aged 2-5 years with cystic fibrosis with a gating mutation followed up for 24 weeks, although the frequency of elevated LFTs suggests that monitoring should be frequent in young children, particularly those with a history of elevated LFTs. Results of an ongoing extension study assessing durability of these effects and longer-term safety are warranted.Vertex Pharmaceuticals Incorporated.

The evidence linking socioeconomic status (SES) and adherence in cystic fibrosis (CF) is inconclusive and focused on medication uptake. We examined associations between SES, adherence to airway clearance therapy (ACT), and CF respiratory outcomes.Socioeconomic, clinical, and adherence data of CF patients (N = 110) at a single CF Center were evaluated in this cross-sectional observational study. SES was operationalized as maternal and paternal education and household income. Adherence to ACT was measured with utilization data from the high-frequency chest wall oscillation (HFCWO) device over 4-6 weeks. Statistical modeling was used to test three hypotheses: (H1) Higher SES is associated with higher ACT adherence; (H2) Higher SES is associated with better respiratory outcomes; and (H3) ACT adherence mediates the relationship between SES and respiratory outcomes.In multinomial logistic regression, maternal college education, annual income$50,000, and more adults in the household were independently related to better adherence (P0.05). Paternal college education, income$100,000, and lack of exposure to smoking were independently related to higher lung function (P0.05). Current adherence to ACT with HFCWO was not associated with lung function over 12 months.SES is associated both with ACT adherence and respiratory outcomes in pediatric CF patients. However, the link between SES and respiratory outcomes in this study was not mediated by adherence to ACT with HFCWO. These data emphasize the importance of socioeconomic resources and household environment for CF health. Family socio-demographic profiles can help identify patients at increased risk for ACT nonadherence.

Assessing airway disease in young children with wheeze and/or cough is challenging. We conducted a prospective, descriptive study of lung function in children3 years old with recurrent wheeze and/or cough, who had failed empiric antiasthma and/or antireflux therapy and subsequently underwent flexible bronchoscopy. Our goals were to describe radiographic, anatomical, microbiological, and physiological findings in these children, and generate hypotheses about their respiratory physiology. Plethysmography and raised-volume rapid thoracoabdominal compression (RVRTC) techniques were performed prior to bronchoscopy. Mean Z-scores (n = 19) were -1.34 for forced expiratory volume at 0.5 sec (FEV(0.5)), -2.28 for forced expiratory flows at 75% of forced vital capacity (FVC) (FEF(75)), -2.25 for forced expiratory flows between 25-75% of FVC (FEF(25-75)), 2.53 for functional residual capacity (FRC), and 2.23 for residual volume divided by total lung capacity (RV/TLC). Younger, shorter children had markedly depressed FEF(75) and FEF(25-75) Z-scores (P = 0.002 and P =0.001, respectively). As expected, lower airway anatomical abnormalities, infection, and inflammation were common. Elevated FRC was associated with anatomical lower airway abnormalities (P = 0.03). FVC was higher in subjects with neutrophilic inflammation (P = 0.03). There was no association between other physiologic variables and bronchoscopic/bronchoalveolar lavage fluid findings. Half of those with elevated RV/TLC ratios (Z-score2) had no evidence of chest radiograph hyperinflation. We conclude that in this population, plethysmography and RVRTC techniques are useful in identifying severity of hyperinflation and airflow obstruction, and we hypothesize that younger children may have relatively small airways caliber, significantly limiting airflow, and thus impairing secretion clearance and predisposing to lower airway infection.

Rationale: The cystic fibrosis transmembrane conductance regulator (CFTR) and Calcium-activated Chloride Conductance (CaCC) each play critical roles in maintaining normal hydration of epithelial surfaces including the airways and colon. TGFbeta is a genetic modifier of cystic fibrosis (CF), but how it influences the CF phenotype is not understood. Objectives: We tested the hypothesis that TGF-beta potently downregulates chloride-channel function and expression in two CF-affected epithelia (T84 colonocytes and primary human airway epithelia) compared with proteins known to be regulated by TGF-beta. Measurements and Main Results: TGF-beta reduced CaCC and CFTR-dependent chloride currents in both epithelia accompanied by reduced levels of TMEM16A and CFTR protein and transcripts. TGF-beta treatment disrupted normal regulation of airway-surface liquid volume in polarized primary human airway epithelia, and reversed F508del CFTR correction produced by VX-809. TGF-beta effects on the expression and activity of TMEM16A, wtCFTR and corrected F508del CFTR were seen at 10-fold lower concentrations relative to TGF-beta effects on e-cadherin (epithelial marker) and vimentin (mesenchymal marker) expression. TGF-beta downregulation of TMEM16A and CFTR expression were partially reversed by Smad3 and p38 MAPK inhibition, respectively. Conclusions: TGF-beta is sufficient to downregulate two critical chloride transporters in two CF-affected tissues that precedes expression changes of two distinct TGF-beta regulated proteins. Our results provide a plausible mechanism for CFdisease modification by TGF-beta through effects on CaCC.

There are no population-based surveillance systems to determine prevalence, impact or outcomes in sickle cell disease (SCD). Estimates of the SCD population in California range broadly from 4,500 to 7,000, and little is known about their health status, health care utilization or health outcomes. A surveillance strategy was implemented using diverse data sources to develop a multi-dimensional, state-based surveillance system for SCD that includes adults and children and describes utilization, treatment and outcomes.Data from California newborn screening, inpatient and emergency room records, Medi-Cal/Medicaid claims and two SCD special care centers were collected for 2004-2008. A multi-step, iterative linkage process was used to link and de-duplicate these data sources, and case definitions were used to categorize cases.After linking and de-duplicating, there were 1,975 confirmed cases of SCD, 3,159 probable cases as well as 8,024 possible cases. Among individual data sources, newborn screening and data from clinics contributed the greatest number of unique cases to the total. Select analyses of utilization and treatments for the population are described.Using linked existing data sources, an estimate of the statewide count of the SCD population is possible. The approach can be used to create an in-depth health status profile of the affected population by aggregating utilization, treatment, and outcomes data including mortality and morbidity information. This effort sets the stage for development of an on-going, state-based surveillance system.

Most public finance analysts recognized the significant redistributive aspects of our current social security system — intragenerational and intergenerational transfers. The intragenerational redistribution is fairly straightforward and well documented. Even though the intergenerational transfers are easily understood and generally agreed upon, the magnitudes of these transfers are not so well reported. The purpose of this paper is to estimate the size of the intergenerational redistribution that has occurred and will continue to occur as a result of our pay‐as‐you‐go system of social security. Based upon average earnings, tax rates, and benefits received under social security, it is possible to estimate the relationship between taxes paid and benefits received for representative individuals who have worked and retired under social security. The preliminary analysis suggests that the usual conclusion about intergenerational redistribution is fundamentally correct, but needs modifying. This research shows that although the earliest retirees received the highest internal rates of return, in terms of real benefits in excess of taxes paid, those individuals who retired between 1970 and 1980 received the largest inflation adjusted transfers. Further, according to the analysis, social security has paid retirees in the aggregate more than $4.5 trillion dollars in benefits above what the recipients have paid in taxes. By the year 2020, when retirees are expected to receive in benefits the amount paid in taxes, this cumulative excess is projected to be about $9.2 trillion.

Rationale TGF-β, a mediator of pulmonary fibrosis, is a genetic modifier of CF respiratory deterioration. The mechanistic relationship between TGF-β signaling and CF lung disease has not been determined. Objective To investigate myofibroblast differentiation in CF lung tissue as a novel pathway by which TGF-β signaling may contribute to pulmonary decline, airway remodeling and tissue fibrosis. Methods Lung samples from CF and non-CF subjects were analyzed morphometrically for total TGF-β1, TGF-β signaling (Smad2 phosphorylation), myofibroblast differentiation (α-smooth muscle actin), and collagen deposition (Masson trichrome stain). Results TGF-β signaling and fibrosis are markedly increased in CF (p

There was an error in the name of the fifth author. The correct name is: Mark MacEwen The correct citation is: Harris WT, Kelly DR, Zhou Y, Wang D, MacEwen M, et al. (2013) Myofibroblast Differentiation and Enhanced Tgf-B Signaling in Cystic Fibrosis Lung Disease. PLoS ONE 8(8): e70196. doi:10.1371/journal.pone.0070196

This paper is an attempt to discuss some economic aspects of metrology, the field of study dealing with measurements. The first part of the paper deals with what might be called the economics of precision; the second discusses the public goods nature of a system of measurement, and the third economic aspect of metrology concerns occupational entry barriers. Even though a market demand and supply in the usual sense do not exist, a system of weights and measures does have many traditional economic characteristics. For example, the measures themselves came about in response to emerging needs to measure with varying degrees of accuracy the commodities that were traded in society. Just as technology has affected the supply of traded goods, so too has it affected the supply of tools of measurement and their precision. The first two sections of the paper will describe our system of weights and measures as an evolutionary process much like how traditional commodity markets work. Individuals and governments have promoted the standardization of units and their accuracy when it served to facilitate a more efficient allocation of resources. The public goods nature of a standardized system of weights and measures will be discussed with emphasis on government involvement. The third section of the paper will discuss some instances in which our system of weights and measures fails to promote economic efficiency. Specifically, we will discuss the rent-seeking behavior by some to implement nonstandard measures as a means of erecting occupational entry barriers.

Cigarette smoking has been acknowledged as the most preventable cause of death and disability in the U.S. According to the U.S. Department of Health and Human Services, smoking causes approximately 400,000 premature deaths annually. These include an estimated 170,000 cases of fatal heart disease, about ninety percent of all lung cancer deaths, and the leading cause of death from larynx, bladder, and esophagus cancer. In terms of disability, it is estimated that about ten million Americans suffer from chronic bronchitis and emphysema which are directly attributable to cigarette smoking (U.S. Department of Health and Human Services, 1991).

Crohn's disease (CD) is a chronic granulomatous disease of unknown etiology that affects primarily the gastrointestinal system but can be associated with extraintestinal manifestations. Latent pulmonary involvement in children with CD has been described, but symptomatic pulmonary disease has rarely been reported in children. In this review, we report two pediatric cases, one with pleural effusion at the time of CD diagnosis and the other with bilateral cavitary lesions in a previously diagnosed CD patient. We review the current literature and summarize the diagnosis and management of pulmonary involvement in CD. Awareness of these pulmonary complications of CD in children may lead to more prompt diagnosis, guide appropriate therapy, and decrease morbidity.